6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
12 @c Identifier of the OpenPGP key used to sign tarballs and such.
13 @set OPENPGP-SIGNING-KEY-ID 3CE464558A84FDC69DB40CFB090B11993D9AEBB5
14 @set OPENPGP-SIGNING-KEY-URL https://sv.gnu.org/people/viewgpg.php?user_id=15145
16 @c Base URL for downloads.
17 @set BASE-URL https://ftp.gnu.org/gnu/guix
19 @c The official substitute server used by default.
20 @set SUBSTITUTE-SERVER ci.guix.gnu.org
21 @set SUBSTITUTE-URL https://@value{SUBSTITUTE-SERVER}
24 Copyright @copyright{} 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès@*
25 Copyright @copyright{} 2013, 2014, 2016 Andreas Enge@*
26 Copyright @copyright{} 2013 Nikita Karetnikov@*
27 Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
28 Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
29 Copyright @copyright{} 2014 Pierre-Antoine Rault@*
30 Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
31 Copyright @copyright{} 2015, 2016, 2017, 2019, 2020 Leo Famulari@*
32 Copyright @copyright{} 2015, 2016, 2017, 2018, 2019, 2020 Ricardo Wurmus@*
33 Copyright @copyright{} 2016 Ben Woodcroft@*
34 Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
35 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Efraim Flashner@*
36 Copyright @copyright{} 2016 John Darrington@*
37 Copyright @copyright{} 2016, 2017 Nikita Gillmann@*
38 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Jan Nieuwenhuizen@*
39 Copyright @copyright{} 2016, 2017, 2018, 2019, 2020 Julien Lepiller@*
40 Copyright @copyright{} 2016 Alex ter Weele@*
41 Copyright @copyright{} 2016, 2017, 2018, 2019 Christopher Baines@*
42 Copyright @copyright{} 2017, 2018, 2019 Clément Lassieur@*
43 Copyright @copyright{} 2017, 2018, 2020 Mathieu Othacehe@*
44 Copyright @copyright{} 2017 Federico Beffa@*
45 Copyright @copyright{} 2017, 2018 Carlo Zancanaro@*
46 Copyright @copyright{} 2017 Thomas Danckaert@*
47 Copyright @copyright{} 2017 humanitiesNerd@*
48 Copyright @copyright{} 2017 Christopher Allan Webber@*
49 Copyright @copyright{} 2017, 2018, 2019, 2020 Marius Bakke@*
50 Copyright @copyright{} 2017, 2019, 2020 Hartmut Goebel@*
51 Copyright @copyright{} 2017, 2019, 2020 Maxim Cournoyer@*
52 Copyright @copyright{} 2017, 2018, 2019, 2020 Tobias Geerinckx-Rice@*
53 Copyright @copyright{} 2017 George Clemmer@*
54 Copyright @copyright{} 2017 Andy Wingo@*
55 Copyright @copyright{} 2017, 2018, 2019, 2020 Arun Isaac@*
56 Copyright @copyright{} 2017 nee@*
57 Copyright @copyright{} 2018 Rutger Helling@*
58 Copyright @copyright{} 2018 Oleg Pykhalov@*
59 Copyright @copyright{} 2018 Mike Gerwitz@*
60 Copyright @copyright{} 2018 Pierre-Antoine Rouby@*
61 Copyright @copyright{} 2018, 2019 Gábor Boskovits@*
62 Copyright @copyright{} 2018, 2019, 2020 Florian Pelz@*
63 Copyright @copyright{} 2018 Laura Lazzati@*
64 Copyright @copyright{} 2018 Alex Vong@*
65 Copyright @copyright{} 2019 Josh Holland@*
66 Copyright @copyright{} 2019, 2020 Diego Nicola Barbato@*
67 Copyright @copyright{} 2019 Ivan Petkov@*
68 Copyright @copyright{} 2019 Jakob L. Kreuze@*
69 Copyright @copyright{} 2019 Kyle Andrews@*
70 Copyright @copyright{} 2019 Alex Griffin@*
71 Copyright @copyright{} 2019, 2020 Guillaume Le Vaillant@*
72 Copyright @copyright{} 2020 Leo Prikler@*
73 Copyright @copyright{} 2019, 2020 Simon Tournier@*
74 Copyright @copyright{} 2020 Wiktor Żelazny@*
75 Copyright @copyright{} 2020 Damien Cassou@*
76 Copyright @copyright{} 2020 Jakub Kądziołka@*
77 Copyright @copyright{} 2020 Jack Hill@*
78 Copyright @copyright{} 2020 Naga Malleswari@*
79 Copyright @copyright{} 2020 Brice Waegeneire@*
80 Copyright @copyright{} 2020 R Veera Kumar@*
81 Copyright @copyright{} 2020 Pierre Langlois@*
82 Copyright @copyright{} 2020 pinoaffe@*
83 Copyright @copyright{} 2020 André Batista@*
84 Copyright @copyright{} 2020 Alexandru-Sergiu Marton@*
85 Copyright @copyright{} 2020 raingloom@*
86 Copyright @copyright{} 2020 Daniel Brooks@*
87 Copyright @copyright{} 2020 John Soo@*
89 Permission is granted to copy, distribute and/or modify this document
90 under the terms of the GNU Free Documentation License, Version 1.3 or
91 any later version published by the Free Software Foundation; with no
92 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
93 copy of the license is included in the section entitled ``GNU Free
94 Documentation License''.
97 @dircategory System administration
99 * Guix: (guix). Manage installed software and system configuration.
100 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
101 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
102 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
103 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
104 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
107 @dircategory Software development
109 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
110 * guix build: (guix)Invoking guix build. Building packages.
111 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
115 @title GNU Guix Reference Manual
116 @subtitle Using the GNU Guix Functional Package Manager
117 @author The GNU Guix Developers
120 @vskip 0pt plus 1filll
121 Edition @value{EDITION} @*
129 @c *********************************************************************
133 This document describes GNU Guix version @value{VERSION}, a functional
134 package management tool written for the GNU system.
136 @c TRANSLATORS: You can replace the following paragraph with information on
137 @c how to join your own translation team and how to report issues with the
139 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
140 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
141 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
142 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
143 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
144 would like to translate it in your native language, consider joining the
145 @uref{https://translationproject.org/domain/guix-manual.html, Translation
149 * Introduction:: What is Guix about?
150 * Installation:: Installing Guix.
151 * System Installation:: Installing the whole operating system.
152 * Getting Started:: Your first steps.
153 * Package Management:: Package installation, upgrade, etc.
154 * Channels:: Customizing the package collection.
155 * Development:: Guix-aided software development.
156 * Programming Interface:: Using Guix in Scheme.
157 * Utilities:: Package management commands.
158 * System Configuration:: Configuring the operating system.
159 * Documentation:: Browsing software user manuals.
160 * Installing Debugging Files:: Feeding the debugger.
161 * Security Updates:: Deploying security fixes quickly.
162 * Bootstrapping:: GNU/Linux built from scratch.
163 * Porting:: Targeting another platform or kernel.
164 * Contributing:: Your help needed!
166 * Acknowledgments:: Thanks!
167 * GNU Free Documentation License:: The license of this manual.
168 * Concept Index:: Concepts.
169 * Programming Index:: Data types, functions, and variables.
172 --- The Detailed Node Listing ---
176 * Managing Software the Guix Way:: What's special.
177 * GNU Distribution:: The packages and tools.
181 * Binary Installation:: Getting Guix running in no time!
182 * Requirements:: Software needed to build and run Guix.
183 * Running the Test Suite:: Testing Guix.
184 * Setting Up the Daemon:: Preparing the build daemon's environment.
185 * Invoking guix-daemon:: Running the build daemon.
186 * Application Setup:: Application-specific setup.
187 * Upgrading Guix:: Upgrading Guix and its build daemon.
189 Setting Up the Daemon
191 * Build Environment Setup:: Preparing the isolated build environment.
192 * Daemon Offload Setup:: Offloading builds to remote machines.
193 * SELinux Support:: Using an SELinux policy for the daemon.
197 * Limitations:: What you can expect.
198 * Hardware Considerations:: Supported hardware.
199 * USB Stick and DVD Installation:: Preparing the installation medium.
200 * Preparing for Installation:: Networking, partitioning, etc.
201 * Guided Graphical Installation:: Easy graphical installation.
202 * Manual Installation:: Manual installation for wizards.
203 * After System Installation:: When installation succeeded.
204 * Installing Guix in a VM:: Guix System playground.
205 * Building the Installation Image:: How this comes to be.
209 * Keyboard Layout and Networking and Partitioning:: Initial setup.
210 * Proceeding with the Installation:: Installing.
214 * Features:: How Guix will make your life brighter.
215 * Invoking guix package:: Package installation, removal, etc.
216 * Substitutes:: Downloading pre-built binaries.
217 * Packages with Multiple Outputs:: Single source package, multiple outputs.
218 * Invoking guix gc:: Running the garbage collector.
219 * Invoking guix pull:: Fetching the latest Guix and distribution.
220 * Invoking guix time-machine:: Running an older revision of Guix.
221 * Inferiors:: Interacting with another revision of Guix.
222 * Invoking guix describe:: Display information about your Guix revision.
223 * Invoking guix archive:: Exporting and importing store files.
227 * Official Substitute Server:: One particular source of substitutes.
228 * Substitute Server Authorization:: How to enable or disable substitutes.
229 * Getting Substitutes from Other Servers:: Substitute diversity.
230 * Substitute Authentication:: How Guix verifies substitutes.
231 * Proxy Settings:: How to get substitutes via proxy.
232 * Substitution Failure:: What happens when substitution fails.
233 * On Trusting Binaries:: How can you trust that binary blob?
237 * Specifying Additional Channels:: Extending the package collection.
238 * Using a Custom Guix Channel:: Using a customized Guix.
239 * Replicating Guix:: Running the @emph{exact same} Guix.
240 * Channel Authentication:: How Guix verifies what it fetches.
241 * Creating a Channel:: How to write your custom channel.
242 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
243 * Declaring Channel Dependencies:: How to depend on other channels.
244 * Specifying Channel Authorizations:: Defining channel authors authorizations.
245 * Primary URL:: Distinguishing mirror to original.
246 * Writing Channel News:: Communicating information to channel's users.
250 * Invoking guix environment:: Setting up development environments.
251 * Invoking guix pack:: Creating software bundles.
252 * The GCC toolchain:: Working with languages supported by GCC.
253 * Invoking guix git authenticate:: Authenticating Git repositories.
255 Programming Interface
257 * Package Modules:: Packages from the programmer's viewpoint.
258 * Defining Packages:: Defining new packages.
259 * Defining Package Variants:: Customizing packages.
260 * Build Systems:: Specifying how packages are built.
261 * Build Phases:: Phases of the build process of a package.
262 * Build Utilities:: Helpers for your package definitions and more.
263 * The Store:: Manipulating the package store.
264 * Derivations:: Low-level interface to package derivations.
265 * The Store Monad:: Purely functional interface to the store.
266 * G-Expressions:: Manipulating build expressions.
267 * Invoking guix repl:: Programming Guix in Guile.
271 * package Reference:: The package data type.
272 * origin Reference:: The origin data type.
276 * Invoking guix build:: Building packages from the command line.
277 * Invoking guix edit:: Editing package definitions.
278 * Invoking guix download:: Downloading a file and printing its hash.
279 * Invoking guix hash:: Computing the cryptographic hash of a file.
280 * Invoking guix import:: Importing package definitions.
281 * Invoking guix refresh:: Updating package definitions.
282 * Invoking guix lint:: Finding errors in package definitions.
283 * Invoking guix size:: Profiling disk usage.
284 * Invoking guix graph:: Visualizing the graph of packages.
285 * Invoking guix publish:: Sharing substitutes.
286 * Invoking guix challenge:: Challenging substitute servers.
287 * Invoking guix copy:: Copying to and from a remote store.
288 * Invoking guix container:: Process isolation.
289 * Invoking guix weather:: Assessing substitute availability.
290 * Invoking guix processes:: Listing client processes.
292 Invoking @command{guix build}
294 * Common Build Options:: Build options for most commands.
295 * Package Transformation Options:: Creating variants of packages.
296 * Additional Build Options:: Options specific to 'guix build'.
297 * Debugging Build Failures:: Real life packaging experience.
301 * Using the Configuration System:: Customizing your GNU system.
302 * operating-system Reference:: Detail of operating-system declarations.
303 * File Systems:: Configuring file system mounts.
304 * Mapped Devices:: Block device extra processing.
305 * User Accounts:: Specifying user accounts.
306 * Keyboard Layout:: How the system interprets key strokes.
307 * Locales:: Language and cultural convention settings.
308 * Services:: Specifying system services.
309 * Setuid Programs:: Programs running with root privileges.
310 * X.509 Certificates:: Authenticating HTTPS servers.
311 * Name Service Switch:: Configuring libc's name service switch.
312 * Initial RAM Disk:: Linux-Libre bootstrapping.
313 * Bootloader Configuration:: Configuring the boot loader.
314 * Invoking guix system:: Instantiating a system configuration.
315 * Invoking guix deploy:: Deploying a system configuration to a remote host.
316 * Running Guix in a VM:: How to run Guix System in a virtual machine.
317 * Defining Services:: Adding new service definitions.
321 * Base Services:: Essential system services.
322 * Scheduled Job Execution:: The mcron service.
323 * Log Rotation:: The rottlog service.
324 * Networking Services:: Network setup, SSH daemon, etc.
325 * Unattended Upgrades:: Automated system upgrades.
326 * X Window:: Graphical display.
327 * Printing Services:: Local and remote printer support.
328 * Desktop Services:: D-Bus and desktop services.
329 * Sound Services:: ALSA and Pulseaudio services.
330 * Database Services:: SQL databases, key-value stores, etc.
331 * Mail Services:: IMAP, POP3, SMTP, and all that.
332 * Messaging Services:: Messaging services.
333 * Telephony Services:: Telephony services.
334 * Monitoring Services:: Monitoring services.
335 * Kerberos Services:: Kerberos services.
336 * LDAP Services:: LDAP services.
337 * Web Services:: Web servers.
338 * Certificate Services:: TLS certificates via Let's Encrypt.
339 * DNS Services:: DNS daemons.
340 * VPN Services:: VPN daemons.
341 * Network File System:: NFS related services.
342 * Continuous Integration:: The Cuirass service.
343 * Power Management Services:: Extending battery life.
344 * Audio Services:: The MPD.
345 * Virtualization Services:: Virtualization services.
346 * Version Control Services:: Providing remote access to Git repositories.
347 * Game Services:: Game servers.
348 * PAM Mount Service:: Service to mount volumes when logging in.
349 * Guix Services:: Services relating specifically to Guix.
350 * Linux Services:: Services tied to the Linux kernel.
351 * Hurd Services:: Services specific for a Hurd System.
352 * Miscellaneous Services:: Other services.
356 * Service Composition:: The model for composing services.
357 * Service Types and Services:: Types and services.
358 * Service Reference:: API reference.
359 * Shepherd Services:: A particular type of service.
361 Installing Debugging Files
363 * Separate Debug Info:: Installing 'debug' outputs.
364 * Rebuilding Debug Info:: Building missing debug info.
368 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
369 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
374 @c *********************************************************************
376 @chapter Introduction
379 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
380 using the international phonetic alphabet (IPA).} is a package
381 management tool for and distribution of the GNU system.
382 Guix makes it easy for unprivileged
383 users to install, upgrade, or remove software packages, to roll back to a
384 previous package set, to build packages from source, and generally
385 assists with the creation and maintenance of software environments.
388 @cindex GuixSD, now Guix System
389 @cindex Guix System Distribution, now Guix System
390 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
391 complements the available tools without interference (@pxref{Installation}),
392 or you can use it as a standalone operating system distribution,
393 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
394 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
395 group everything under the ``Guix'' banner since, after all, Guix System is
396 readily available through the @command{guix system} command, even if you're
397 using a different distro underneath!}. @xref{GNU Distribution}.
400 * Managing Software the Guix Way:: What's special.
401 * GNU Distribution:: The packages and tools.
404 @node Managing Software the Guix Way
405 @section Managing Software the Guix Way
407 @cindex user interfaces
408 Guix provides a command-line package management interface
409 (@pxref{Package Management}), tools to help with software development
410 (@pxref{Development}), command-line utilities for more advanced usage
411 (@pxref{Utilities}), as well as Scheme programming interfaces
412 (@pxref{Programming Interface}).
414 Its @dfn{build daemon} is responsible for building packages on behalf of
415 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
416 binaries from authorized sources (@pxref{Substitutes}).
418 @cindex extensibility of the distribution
419 @cindex customization, of packages
420 Guix includes package definitions for many GNU and non-GNU packages, all
421 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
422 user's computing freedom}. It is @emph{extensible}: users can write
423 their own package definitions (@pxref{Defining Packages}) and make them
424 available as independent package modules (@pxref{Package Modules}). It
425 is also @emph{customizable}: users can @emph{derive} specialized package
426 definitions from existing ones, including from the command line
427 (@pxref{Package Transformation Options}).
429 @cindex functional package management
431 Under the hood, Guix implements the @dfn{functional package management}
432 discipline pioneered by Nix (@pxref{Acknowledgments}).
433 In Guix, the package build and installation process is seen
434 as a @emph{function}, in the mathematical sense. That function takes inputs,
435 such as build scripts, a compiler, and libraries, and
436 returns an installed package. As a pure function, its result depends
437 solely on its inputs---for instance, it cannot refer to software or
438 scripts that were not explicitly passed as inputs. A build function
439 always produces the same result when passed a given set of inputs. It
440 cannot alter the environment of the running system in
441 any way; for instance, it cannot create, modify, or delete files outside
442 of its build and installation directories. This is achieved by running
443 build processes in isolated environments (or @dfn{containers}), where only their
444 explicit inputs are visible.
447 The result of package build functions is @dfn{cached} in the file
448 system, in a special directory called @dfn{the store} (@pxref{The
449 Store}). Each package is installed in a directory of its own in the
450 store---by default under @file{/gnu/store}. The directory name contains
451 a hash of all the inputs used to build that package; thus, changing an
452 input yields a different directory name.
454 This approach is the foundation for the salient features of Guix: support
455 for transactional package upgrade and rollback, per-user installation, and
456 garbage collection of packages (@pxref{Features}).
459 @node GNU Distribution
460 @section GNU Distribution
463 Guix comes with a distribution of the GNU system consisting entirely of
464 free software@footnote{The term ``free'' here refers to the
465 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
466 users of that software}.}. The
467 distribution can be installed on its own (@pxref{System Installation}),
468 but it is also possible to install Guix as a package manager on top of
469 an installed GNU/Linux system (@pxref{Installation}). When we need to
470 distinguish between the two, we refer to the standalone distribution as
473 The distribution provides core GNU packages such as GNU libc, GCC, and
474 Binutils, as well as many GNU and non-GNU applications. The complete
475 list of available packages can be browsed
476 @url{https://www.gnu.org/software/guix/packages,on-line} or by
477 running @command{guix package} (@pxref{Invoking guix package}):
480 guix package --list-available
483 Our goal is to provide a practical 100% free software distribution of
484 Linux-based and other variants of GNU, with a focus on the promotion and
485 tight integration of GNU components, and an emphasis on programs and
486 tools that help users exert that freedom.
488 Packages are currently available on the following platforms:
493 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel.
496 Intel 32-bit architecture (IA32), Linux-Libre kernel.
499 ARMv7-A architecture with hard float, Thumb-2 and NEON,
500 using the EABI hard-float application binary interface (ABI),
501 and Linux-Libre kernel.
504 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
507 @uref{https://hurd.gnu.org, GNU/Hurd} on the Intel 32-bit architecture
510 This configuration is experimental and under development. The easiest
511 way for you to give it a try is by setting up an instance of
512 @code{hurd-vm-service-type} on your GNU/Linux machine
513 (@pxref{transparent-emulation-qemu, @code{hurd-vm-service-type}}).
514 @xref{Contributing}, on how to help!
516 @item mips64el-linux (deprecated)
517 little-endian 64-bit MIPS processors, specifically the Loongson series,
518 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
519 supported; in particular, there is no ongoing work to ensure that this
520 architecture still works. Should someone decide they wish to revive this
521 architecture then the code is still available.
525 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
526 configuration and Guix takes care of instantiating the configuration in a
527 transactional, reproducible, and stateless fashion (@pxref{System
528 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
529 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
530 Manual}), the well-known GNU utilities and tool chain, as well as the
531 graphical environment or system services of your choice.
533 Guix System is available on all the above platforms except
534 @code{mips64el-linux}.
537 For information on porting to other architectures or kernels,
540 Building this distribution is a cooperative effort, and you are invited
541 to join! @xref{Contributing}, for information about how you can help.
544 @c *********************************************************************
546 @chapter Installation
548 @cindex installing Guix
551 We recommend the use of this
552 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
553 shell installer script} to install Guix on top of a running GNU/Linux system,
554 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
555 with the installation of the package manager, which can be done on top of a
556 running GNU/Linux system. If, instead, you want to install the complete GNU
557 operating system, @pxref{System Installation}.} The script automates the
558 download, installation, and initial configuration of Guix. It should be run
562 @cindex foreign distro
563 @cindex directories related to foreign distro
564 When installed on a foreign distro, GNU@tie{}Guix complements the available
565 tools without interference. Its data lives exclusively in two directories,
566 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
567 such as @file{/etc}, are left untouched.
569 Once installed, Guix can be updated by running @command{guix pull}
570 (@pxref{Invoking guix pull}).
572 If you prefer to perform the installation steps manually or want to tweak
573 them, you may find the following subsections useful. They describe the
574 software requirements of Guix, as well as how to install it manually and get
578 * Binary Installation:: Getting Guix running in no time!
579 * Requirements:: Software needed to build and run Guix.
580 * Running the Test Suite:: Testing Guix.
581 * Setting Up the Daemon:: Preparing the build daemon's environment.
582 * Invoking guix-daemon:: Running the build daemon.
583 * Application Setup:: Application-specific setup.
584 * Upgrading Guix:: Upgrading Guix and its build daemon.
587 @node Binary Installation
588 @section Binary Installation
590 @cindex installing Guix from binaries
591 @cindex installer script
592 This section describes how to install Guix on an arbitrary system from a
593 self-contained tarball providing binaries for Guix and for all its
594 dependencies. This is often quicker than installing from source, which
595 is described in the next sections. The only requirement is to have
598 @c Note duplicated from the ``Installation'' node.
600 We recommend the use of this
601 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
602 shell installer script}. The script automates the download, installation, and
603 initial configuration steps described below. It should be run as the root
604 user. As root, you can thus run this:
608 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
609 chmod +x guix-install.sh
613 When you're done, @pxref{Application Setup} for extra configuration you
614 might need, and @ref{Getting Started} for your first steps!
617 Installing goes along these lines:
621 @cindex downloading Guix binary
622 Download the binary tarball from
623 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
624 where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
625 @code{i686} (32-bits) machine already running the kernel Linux, and so on
626 (@pxref{GNU Distribution}).
628 @c The following is somewhat duplicated in ``System Installation''.
629 Make sure to download the associated @file{.sig} file and to verify the
630 authenticity of the tarball against it, along these lines:
633 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
634 $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
637 If that command fails because you do not have the required public key,
638 then run this command to import it:
641 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
642 -qO - | gpg --import -
646 and rerun the @code{gpg --verify} command.
648 Take note that a warning like ``This key is not certified with a trusted
649 signature!'' is normal.
651 @c end authentication part
654 Now, you need to become the @code{root} user. Depending on your distribution,
655 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
659 # tar --warning=no-timestamp -xf \
660 /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
661 # mv var/guix /var/ && mv gnu /
664 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
665 The latter contains a ready-to-use profile for @code{root} (see next
668 Do @emph{not} unpack the tarball on a working Guix system since that
669 would overwrite its own essential files.
671 The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
672 not emit warnings about ``implausibly old time stamps'' (such
673 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
675 They stem from the fact that all the
676 files in the archive have their modification time set to 1 (which
677 means January 1st, 1970). This is done on purpose to make sure the
678 archive content is independent of its creation time, thus making it
682 Make the profile available under @file{~root/.config/guix/current}, which is
683 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
686 # mkdir -p ~root/.config/guix
687 # ln -sf /var/guix/profiles/per-user/root/current-guix \
688 ~root/.config/guix/current
691 Source @file{etc/profile} to augment @env{PATH} and other relevant
692 environment variables:
695 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
696 source $GUIX_PROFILE/etc/profile
700 Create the group and user accounts for build users as explained below
701 (@pxref{Build Environment Setup}).
704 Run the daemon, and set it to automatically start on boot.
706 If your host distro uses the systemd init system, this can be achieved
709 @c Versions of systemd that supported symlinked service files are not
710 @c yet widely deployed, so we should suggest that users copy the service
713 @c See this thread for more information:
714 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
717 # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
718 ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
720 # systemctl enable --now gnu-store.mount guix-daemon
723 If your host distro uses the Upstart init system:
726 # initctl reload-configuration
727 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
732 Otherwise, you can still start the daemon manually with:
735 # ~root/.config/guix/current/bin/guix-daemon \
736 --build-users-group=guixbuild
740 Make the @command{guix} command available to other users on the machine,
744 # mkdir -p /usr/local/bin
746 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
749 It is also a good idea to make the Info version of this manual available
753 # mkdir -p /usr/local/share/info
754 # cd /usr/local/share/info
755 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
759 That way, assuming @file{/usr/local/share/info} is in the search path,
760 running @command{info guix} will open this manual (@pxref{Other Info
761 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
765 @cindex substitutes, authorization thereof
766 To use substitutes from @code{@value{SUBSTITUTE-SERVER}} or one of its mirrors
767 (@pxref{Substitutes}), authorize them:
770 # guix archive --authorize < \
771 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER}.pub
775 Each user may need to perform a few additional steps to make their Guix
776 environment ready for use, @pxref{Application Setup}.
779 Voilà, the installation is complete!
781 You can confirm that Guix is working by installing a sample package into
788 The binary installation tarball can be (re)produced and verified simply
789 by running the following command in the Guix source tree:
792 make guix-binary.@var{system}.tar.xz
796 ...@: which, in turn, runs:
799 guix pack -s @var{system} --localstatedir \
800 --profile-name=current-guix guix
803 @xref{Invoking guix pack}, for more info on this handy tool.
806 @section Requirements
808 This section lists requirements when building Guix from source. The
809 build procedure for Guix is the same as for other GNU software, and is
810 not covered here. Please see the files @file{README} and @file{INSTALL}
811 in the Guix source tree for additional details.
813 @cindex official website
814 GNU Guix is available for download from its website at
815 @url{https://www.gnu.org/software/guix/}.
817 GNU Guix depends on the following packages:
820 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x or
822 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
825 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
826 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
827 Guile,, gnutls-guile, GnuTLS-Guile});
829 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
831 @item @uref{https://notabug.org/guile-zlib/guile-zlib, Guile-zlib};
832 @item @uref{https://notabug.org/guile-lzlib/guile-lzlib, Guile-lzlib};
833 @item @uref{https://www.nongnu.org/guile-avahi/, Guile-Avahi};
835 @c FIXME: Specify a version number once a release has been made.
836 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, version 0.3.0
838 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON}
840 @item @url{https://www.gnu.org/software/make/, GNU Make}.
843 The following dependencies are optional:
847 @c Note: We need at least 0.13.0 for #:nodelay.
848 Support for build offloading (@pxref{Daemon Offload Setup}) and
849 @command{guix copy} (@pxref{Invoking guix copy}) depends on
850 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
851 version 0.13.0 or later.
854 @uref{https://ngyro.com/software/guile-semver.html, Guile-Semver} for
855 the @code{crate} importer (@pxref{Invoking guix import}).
858 When @url{http://www.bzip.org, libbz2} is available,
859 @command{guix-daemon} can use it to compress build logs.
862 Unless @option{--disable-daemon} was passed to @command{configure}, the
863 following packages are also needed:
866 @item @url{https://gnupg.org/, GNU libgcrypt};
867 @item @url{https://sqlite.org, SQLite 3};
868 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
872 @cindex state directory
873 When configuring Guix on a system that already has a Guix installation,
874 be sure to specify the same state directory as the existing installation
875 using the @option{--localstatedir} option of the @command{configure}
876 script (@pxref{Directory Variables, @code{localstatedir},, standards,
877 GNU Coding Standards}). Usually, this @var{localstatedir} option is
878 set to the value @file{/var}. The @command{configure} script protects
879 against unintended misconfiguration of @var{localstatedir} so you do not
880 inadvertently corrupt your store (@pxref{The Store}).
882 @node Running the Test Suite
883 @section Running the Test Suite
886 After a successful @command{configure} and @code{make} run, it is a good
887 idea to run the test suite. It can help catch issues with the setup or
888 environment, or bugs in Guix itself---and really, reporting test
889 failures is a good way to help improve the software. To run the test
896 Test cases can run in parallel: you can use the @code{-j} option of
897 GNU@tie{}make to speed things up. The first run may take a few minutes
898 on a recent machine; subsequent runs will be faster because the store
899 that is created for test purposes will already have various things in
902 It is also possible to run a subset of the tests by defining the
903 @code{TESTS} makefile variable as in this example:
906 make check TESTS="tests/store.scm tests/cpio.scm"
909 By default, tests results are displayed at a file level. In order to
910 see the details of every individual test cases, it is possible to define
911 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
914 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
917 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
918 @file{test-suite.log} file. Please specify the Guix version being used
919 as well as version numbers of the dependencies (@pxref{Requirements}) in
922 Guix also comes with a whole-system test suite that tests complete
923 Guix System instances. It can only run on systems where
924 Guix is already installed, using:
931 or, again, by defining @code{TESTS} to select a subset of tests to run:
934 make check-system TESTS="basic mcron"
937 These system tests are defined in the @code{(gnu tests @dots{})}
938 modules. They work by running the operating systems under test with
939 lightweight instrumentation in a virtual machine (VM). They can be
940 computationally intensive or rather cheap, depending on whether
941 substitutes are available for their dependencies (@pxref{Substitutes}).
942 Some of them require a lot of storage space to hold VM images.
944 Again in case of test failures, please send @email{bug-guix@@gnu.org}
947 @node Setting Up the Daemon
948 @section Setting Up the Daemon
951 Operations such as building a package or running the garbage collector
952 are all performed by a specialized process, the @dfn{build daemon}, on
953 behalf of clients. Only the daemon may access the store and its
954 associated database. Thus, any operation that manipulates the store
955 goes through the daemon. For instance, command-line tools such as
956 @command{guix package} and @command{guix build} communicate with the
957 daemon (@i{via} remote procedure calls) to instruct it what to do.
959 The following sections explain how to prepare the build daemon's
960 environment. See also @ref{Substitutes}, for information on how to allow
961 the daemon to download pre-built binaries.
964 * Build Environment Setup:: Preparing the isolated build environment.
965 * Daemon Offload Setup:: Offloading builds to remote machines.
966 * SELinux Support:: Using an SELinux policy for the daemon.
969 @node Build Environment Setup
970 @subsection Build Environment Setup
972 @cindex build environment
973 In a standard multi-user setup, Guix and its daemon---the
974 @command{guix-daemon} program---are installed by the system
975 administrator; @file{/gnu/store} is owned by @code{root} and
976 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
977 Guix tools to build packages or otherwise access the store, and the
978 daemon will do it on their behalf, ensuring that the store is kept in a
979 consistent state, and allowing built packages to be shared among users.
982 When @command{guix-daemon} runs as @code{root}, you may not want package
983 build processes themselves to run as @code{root} too, for obvious
984 security reasons. To avoid that, a special pool of @dfn{build users}
985 should be created for use by build processes started by the daemon.
986 These build users need not have a shell and a home directory: they will
987 just be used when the daemon drops @code{root} privileges in build
988 processes. Having several such users allows the daemon to launch
989 distinct build processes under separate UIDs, which guarantees that they
990 do not interfere with each other---an essential feature since builds are
991 regarded as pure functions (@pxref{Introduction}).
993 On a GNU/Linux system, a build user pool may be created like this (using
994 Bash syntax and the @code{shadow} commands):
996 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
997 @c for why `-G' is needed.
999 # groupadd --system guixbuild
1000 # for i in `seq -w 1 10`;
1002 useradd -g guixbuild -G guixbuild \
1003 -d /var/empty -s `which nologin` \
1004 -c "Guix build user $i" --system \
1010 The number of build users determines how many build jobs may run in
1011 parallel, as specified by the @option{--max-jobs} option
1012 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
1013 @command{guix system vm} and related commands, you may need to add the
1014 build users to the @code{kvm} group so they can access @file{/dev/kvm},
1015 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
1016 (@pxref{Invoking guix system}).
1018 The @code{guix-daemon} program may then be run as @code{root} with the
1019 following command@footnote{If your machine uses the systemd init system,
1020 dropping the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
1021 file in @file{/etc/systemd/system} will ensure that
1022 @command{guix-daemon} is automatically started. Similarly, if your
1023 machine uses the Upstart init system, drop the
1024 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
1025 file in @file{/etc/init}.}:
1028 # guix-daemon --build-users-group=guixbuild
1033 This way, the daemon starts build processes in a chroot, under one of
1034 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
1035 environment contains nothing but:
1037 @c Keep this list in sync with libstore/build.cc! -----------------------
1040 a minimal @code{/dev} directory, created mostly independently from the
1041 host @code{/dev}@footnote{``Mostly'', because while the set of files
1042 that appear in the chroot's @code{/dev} is fixed, most of these files
1043 can only be created if the host has them.};
1046 the @code{/proc} directory; it only shows the processes of the container
1047 since a separate PID name space is used;
1050 @file{/etc/passwd} with an entry for the current user and an entry for
1054 @file{/etc/group} with an entry for the user's group;
1057 @file{/etc/hosts} with an entry that maps @code{localhost} to
1061 a writable @file{/tmp} directory.
1064 You can influence the directory where the daemon stores build trees
1065 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1066 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1067 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1068 This way, the value of @env{TMPDIR} does not leak inside build
1069 environments, which avoids discrepancies in cases where build processes
1070 capture the name of their build tree.
1074 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1075 environment variables for HTTP and HTTPS downloads it performs, be it
1076 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1077 (@pxref{Substitutes}).
1079 If you are installing Guix as an unprivileged user, it is still possible
1080 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1081 However, build processes will not be isolated from one another, and not
1082 from the rest of the system. Thus, build processes may interfere with
1083 each other, and may access programs, libraries, and other files
1084 available on the system---making it much harder to view them as
1085 @emph{pure} functions.
1088 @node Daemon Offload Setup
1089 @subsection Using the Offload Facility
1093 When desired, the build daemon can @dfn{offload} derivation builds to
1094 other machines running Guix, using the @code{offload} @dfn{build
1095 hook}@footnote{This feature is available only when
1096 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1097 present.}. When that feature is enabled, a list of user-specified build
1098 machines is read from @file{/etc/guix/machines.scm}; every time a build
1099 is requested, for instance via @code{guix build}, the daemon attempts to
1100 offload it to one of the machines that satisfy the constraints of the
1101 derivation, in particular its system types---e.g., @code{x86_64-linux}.
1102 A single machine can have multiple system types, either because its
1103 architecture natively supports it, via emulation
1104 (@pxref{transparent-emulation-qemu, Transparent Emulation with QEMU}),
1105 or both. Missing prerequisites for the build are
1106 copied over SSH to the target machine, which then proceeds with the
1107 build; upon success the output(s) of the build are copied back to the
1108 initial machine. The offload facility comes with a basic scheduler that
1109 attempts to select the best machine. The best machine is chosen among
1110 the available machines based on criteria such as:
1114 The availability of a build slot. A build machine can have as many
1115 build slots (connections) as the value of the @code{parallel-builds}
1116 field of its @code{build-machine} object.
1119 Its relative speed, as defined via the @code{speed} field of its
1120 @code{build-machine} object.
1123 Its load. The normalized machine load must be lower than a threshold
1124 value, configurable via the @code{overload-threshold} field of its
1125 @code{build-machine} object.
1128 Disk space availability. More than a 100 MiB must be available.
1131 The @file{/etc/guix/machines.scm} file typically looks like this:
1134 (list (build-machine
1135 (name "eightysix.example.org")
1136 (systems (list "x86_64-linux" "i686-linux"))
1137 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1139 (speed 2.)) ;incredibly fast!
1142 (name "armeight.example.org")
1143 (systems (list "aarch64-linux"))
1144 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1147 (string-append (getenv "HOME")
1148 "/.ssh/identity-for-guix"))))
1152 In the example above we specify a list of two build machines, one for
1153 the @code{x86_64} and @code{i686} architectures and one for the
1154 @code{aarch64} architecture.
1156 In fact, this file is---not surprisingly!---a Scheme file that is
1157 evaluated when the @code{offload} hook is started. Its return value
1158 must be a list of @code{build-machine} objects. While this example
1159 shows a fixed list of build machines, one could imagine, say, using
1160 DNS-SD to return a list of potential build machines discovered in the
1161 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1162 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1165 @deftp {Data Type} build-machine
1166 This data type represents build machines to which the daemon may offload
1167 builds. The important fields are:
1172 The host name of the remote machine.
1175 The system types the remote machine supports---e.g., @code{(list
1176 "x86_64-linux" "i686-linux")}.
1179 The user account to use when connecting to the remote machine over SSH.
1180 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1181 allow non-interactive logins.
1184 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1185 This is used to authenticate the machine when we connect to it. It is a
1186 long string that looks like this:
1189 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1192 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1193 key can be found in a file such as
1194 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1196 If the machine is running the SSH daemon of GNU@tie{}lsh,
1197 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1198 similar file. It can be converted to the OpenSSH format using
1199 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1202 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1203 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1208 A number of optional fields may be specified:
1212 @item @code{port} (default: @code{22})
1213 Port number of SSH server on the machine.
1215 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1216 The SSH private key file to use when connecting to the machine, in
1217 OpenSSH format. This key must not be protected with a passphrase.
1219 Note that the default value is the private key @emph{of the root
1220 account}. Make sure it exists if you use the default.
1222 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1223 @itemx @code{compression-level} (default: @code{3})
1224 The SSH-level compression methods and compression level requested.
1226 Note that offloading relies on SSH compression to reduce bandwidth usage
1227 when transferring files to and from build machines.
1229 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1230 File name of the Unix-domain socket @command{guix-daemon} is listening
1233 @item @code{overload-threshold} (default: @code{0.6})
1234 The load threshold above which a potential offload machine is
1235 disregarded by the offload scheduler. The value roughly translates to
1236 the total processor usage of the build machine, ranging from 0.0 (0%) to
1237 1.0 (100%). It can also be disabled by setting
1238 @code{overload-threshold} to @code{#f}.
1240 @item @code{parallel-builds} (default: @code{1})
1241 The number of builds that may run in parallel on the machine.
1243 @item @code{speed} (default: @code{1.0})
1244 A ``relative speed factor''. The offload scheduler will tend to prefer
1245 machines with a higher speed factor.
1247 @item @code{features} (default: @code{'()})
1248 A list of strings denoting specific features supported by the machine.
1249 An example is @code{"kvm"} for machines that have the KVM Linux modules
1250 and corresponding hardware support. Derivations can request features by
1251 name, and they will be scheduled on matching build machines.
1256 The @command{guix} command must be in the search path on the build
1257 machines. You can check whether this is the case by running:
1260 ssh build-machine guix repl --version
1263 There is one last thing to do once @file{machines.scm} is in place. As
1264 explained above, when offloading, files are transferred back and forth
1265 between the machine stores. For this to work, you first need to
1266 generate a key pair on each machine to allow the daemon to export signed
1267 archives of files from the store (@pxref{Invoking guix archive}):
1270 # guix archive --generate-key
1274 Each build machine must authorize the key of the master machine so that
1275 it accepts store items it receives from the master:
1278 # guix archive --authorize < master-public-key.txt
1282 Likewise, the master machine must authorize the key of each build machine.
1284 All the fuss with keys is here to express pairwise mutual trust
1285 relations between the master and the build machines. Concretely, when
1286 the master receives files from a build machine (and @i{vice versa}), its
1287 build daemon can make sure they are genuine, have not been tampered
1288 with, and that they are signed by an authorized key.
1290 @cindex offload test
1291 To test whether your setup is operational, run this command on the
1298 This will attempt to connect to each of the build machines specified in
1299 @file{/etc/guix/machines.scm}, make sure Guile and the Guix modules are
1300 available on each machine, attempt to export to the machine and import
1301 from it, and report any error in the process.
1303 If you want to test a different machine file, just specify it on the
1307 # guix offload test machines-qualif.scm
1310 Last, you can test the subset of the machines whose name matches a
1311 regular expression like this:
1314 # guix offload test machines.scm '\.gnu\.org$'
1317 @cindex offload status
1318 To display the current load of all build hosts, run this command on the
1322 # guix offload status
1326 @node SELinux Support
1327 @subsection SELinux Support
1329 @cindex SELinux, daemon policy
1330 @cindex mandatory access control, SELinux
1331 @cindex security, guix-daemon
1332 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1333 can be installed on a system where SELinux is enabled, in order to label
1334 Guix files and to specify the expected behavior of the daemon. Since
1335 Guix System does not provide an SELinux base policy, the daemon policy cannot
1336 be used on Guix System.
1338 @subsubsection Installing the SELinux policy
1339 @cindex SELinux, policy installation
1340 To install the policy run this command as root:
1343 semodule -i etc/guix-daemon.cil
1346 Then relabel the file system with @code{restorecon} or by a different
1347 mechanism provided by your system.
1349 Once the policy is installed, the file system has been relabeled, and
1350 the daemon has been restarted, it should be running in the
1351 @code{guix_daemon_t} context. You can confirm this with the following
1355 ps -Zax | grep guix-daemon
1358 Monitor the SELinux log files as you run a command like @code{guix build
1359 hello} to convince yourself that SELinux permits all necessary
1362 @subsubsection Limitations
1363 @cindex SELinux, limitations
1365 This policy is not perfect. Here is a list of limitations or quirks
1366 that should be considered when deploying the provided SELinux policy for
1371 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1372 operations involve contexts that have anything to do with
1373 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1374 but it would be preferrable to define socket rules for only this label.
1377 @code{guix gc} cannot access arbitrary links to profiles. By design,
1378 the file label of the destination of a symlink is independent of the
1379 file label of the link itself. Although all profiles under
1380 $localstatedir are labelled, the links to these profiles inherit the
1381 label of the directory they are in. For links in the user’s home
1382 directory this will be @code{user_home_t}. But for links from the root
1383 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1384 directory, etc, this won’t work. @code{guix gc} would be prevented from
1385 reading and following these links.
1388 The daemon’s feature to listen for TCP connections might no longer work.
1389 This might require extra rules, because SELinux treats network sockets
1390 differently from files.
1393 Currently all files with a name matching the regular expression
1394 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1395 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1396 that name in any profile would be permitted to run in the
1397 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1398 build a package that provides this executable and convince a user to
1399 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1400 At that point SELinux could not prevent it from accessing files that are
1401 allowed for processes in that domain.
1403 You will need to relabel the store directory after all upgrades to
1404 @file{guix-daemon}, such as after running @code{guix pull}. Assuming the
1405 store is in @file{/gnu}, you can do this with @code{restorecon -vR /gnu},
1406 or by other means provided by your operating system.
1408 We could generate a much more restrictive policy at installation time,
1409 so that only the @emph{exact} file name of the currently installed
1410 @code{guix-daemon} executable would be labelled with
1411 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1412 The downside is that root would have to install or upgrade the policy at
1413 installation time whenever the Guix package that provides the
1414 effectively running @code{guix-daemon} executable is upgraded.
1417 @node Invoking guix-daemon
1418 @section Invoking @command{guix-daemon}
1420 The @command{guix-daemon} program implements all the functionality to
1421 access the store. This includes launching build processes, running the
1422 garbage collector, querying the availability of a build result, etc. It
1423 is normally run as @code{root} like this:
1426 # guix-daemon --build-users-group=guixbuild
1430 For details on how to set it up, @pxref{Setting Up the Daemon}.
1433 @cindex container, build environment
1434 @cindex build environment
1435 @cindex reproducible builds
1436 By default, @command{guix-daemon} launches build processes under
1437 different UIDs, taken from the build group specified with
1438 @option{--build-users-group}. In addition, each build process is run in a
1439 chroot environment that only contains the subset of the store that the
1440 build process depends on, as specified by its derivation
1441 (@pxref{Programming Interface, derivation}), plus a set of specific
1442 system directories. By default, the latter contains @file{/dev} and
1443 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1444 @dfn{container}: in addition to having its own file system tree, it has
1445 a separate mount name space, its own PID name space, network name space,
1446 etc. This helps achieve reproducible builds (@pxref{Features}).
1448 When the daemon performs a build on behalf of the user, it creates a
1449 build directory under @file{/tmp} or under the directory specified by
1450 its @env{TMPDIR} environment variable. This directory is shared with
1451 the container for the duration of the build, though within the container,
1452 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1454 The build directory is automatically deleted upon completion, unless the
1455 build failed and the client specified @option{--keep-failed}
1456 (@pxref{Invoking guix build, @option{--keep-failed}}).
1458 The daemon listens for connections and spawns one sub-process for each session
1459 started by a client (one of the @command{guix} sub-commands). The
1460 @command{guix processes} command allows you to get an overview of the activity
1461 on your system by viewing each of the active sessions and clients.
1462 @xref{Invoking guix processes}, for more information.
1464 The following command-line options are supported:
1467 @item --build-users-group=@var{group}
1468 Take users from @var{group} to run build processes (@pxref{Setting Up
1469 the Daemon, build users}).
1471 @item --no-substitutes
1473 Do not use substitutes for build products. That is, always build things
1474 locally instead of allowing downloads of pre-built binaries
1475 (@pxref{Substitutes}).
1477 When the daemon runs with @option{--no-substitutes}, clients can still
1478 explicitly enable substitution @i{via} the @code{set-build-options}
1479 remote procedure call (@pxref{The Store}).
1481 @anchor{daemon-substitute-urls}
1482 @item --substitute-urls=@var{urls}
1483 Consider @var{urls} the default whitespace-separated list of substitute
1484 source URLs. When this option is omitted,
1485 @indicateurl{https://@value{SUBSTITUTE-SERVER}} is used.
1487 This means that substitutes may be downloaded from @var{urls}, as long
1488 as they are signed by a trusted signature (@pxref{Substitutes}).
1490 @xref{Getting Substitutes from Other Servers}, for more information on
1491 how to configure the daemon to get substitutes from other servers.
1495 Do not use offload builds to other machines (@pxref{Daemon Offload
1496 Setup}). That is, always build things locally instead of offloading
1497 builds to remote machines.
1499 @item --cache-failures
1500 Cache build failures. By default, only successful builds are cached.
1502 When this option is used, @command{guix gc --list-failures} can be used
1503 to query the set of store items marked as failed; @command{guix gc
1504 --clear-failures} removes store items from the set of cached failures.
1505 @xref{Invoking guix gc}.
1507 @item --cores=@var{n}
1509 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1512 The default value is @code{0}, but it may be overridden by clients, such
1513 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1516 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1517 in the build process, which can then use it to exploit internal
1518 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1520 @item --max-jobs=@var{n}
1522 Allow at most @var{n} build jobs in parallel. The default value is
1523 @code{1}. Setting it to @code{0} means that no builds will be performed
1524 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1525 Setup}), or simply fail.
1527 @item --max-silent-time=@var{seconds}
1528 When the build or substitution process remains silent for more than
1529 @var{seconds}, terminate it and report a build failure.
1531 The default value is @code{0}, which disables the timeout.
1533 The value specified here can be overridden by clients (@pxref{Common
1534 Build Options, @option{--max-silent-time}}).
1536 @item --timeout=@var{seconds}
1537 Likewise, when the build or substitution process lasts for more than
1538 @var{seconds}, terminate it and report a build failure.
1540 The default value is @code{0}, which disables the timeout.
1542 The value specified here can be overridden by clients (@pxref{Common
1543 Build Options, @option{--timeout}}).
1545 @item --rounds=@var{N}
1546 Build each derivation @var{n} times in a row, and raise an error if
1547 consecutive build results are not bit-for-bit identical. Note that this
1548 setting can be overridden by clients such as @command{guix build}
1549 (@pxref{Invoking guix build}).
1551 When used in conjunction with @option{--keep-failed}, the differing
1552 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1553 This makes it easy to look for differences between the two results.
1556 Produce debugging output.
1558 This is useful to debug daemon start-up issues, but then it may be
1559 overridden by clients, for example the @option{--verbosity} option of
1560 @command{guix build} (@pxref{Invoking guix build}).
1562 @item --chroot-directory=@var{dir}
1563 Add @var{dir} to the build chroot.
1565 Doing this may change the result of build processes---for instance if
1566 they use optional dependencies found in @var{dir} when it is available,
1567 and not otherwise. For that reason, it is not recommended to do so.
1568 Instead, make sure that each derivation declares all the inputs that it
1571 @item --disable-chroot
1572 Disable chroot builds.
1574 Using this option is not recommended since, again, it would allow build
1575 processes to gain access to undeclared dependencies. It is necessary,
1576 though, when @command{guix-daemon} is running under an unprivileged user
1579 @item --log-compression=@var{type}
1580 Compress build logs according to @var{type}, one of @code{gzip},
1581 @code{bzip2}, or @code{none}.
1583 Unless @option{--lose-logs} is used, all the build logs are kept in the
1584 @var{localstatedir}. To save space, the daemon automatically compresses
1585 them with Bzip2 by default.
1587 @item --discover[=yes|no]
1588 Whether to discover substitute servers on the local network using mDNS
1591 This feature is still experimental. However, here are a few
1596 It might be faster/less expensive than fetching from remote servers;
1598 There are no security risks, only genuine substitutes will be used
1599 (@pxref{Substitute Authentication});
1601 An attacker advertising @command{guix publish} on your LAN cannot serve
1602 you malicious binaries, but they can learn what software you’re
1605 Servers may serve substitute over HTTP, unencrypted, so anyone on the
1606 LAN can see what software you’re installing.
1609 @item --disable-deduplication
1610 @cindex deduplication
1611 Disable automatic file ``deduplication'' in the store.
1613 By default, files added to the store are automatically ``deduplicated'':
1614 if a newly added file is identical to another one found in the store,
1615 the daemon makes the new file a hard link to the other file. This can
1616 noticeably reduce disk usage, at the expense of slightly increased
1617 input/output load at the end of a build process. This option disables
1620 @item --gc-keep-outputs[=yes|no]
1621 Tell whether the garbage collector (GC) must keep outputs of live
1625 @cindex garbage collector roots
1626 When set to @code{yes}, the GC will keep the outputs of any live
1627 derivation available in the store---the @file{.drv} files. The default
1628 is @code{no}, meaning that derivation outputs are kept only if they are
1629 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1632 @item --gc-keep-derivations[=yes|no]
1633 Tell whether the garbage collector (GC) must keep derivations
1634 corresponding to live outputs.
1636 When set to @code{yes}, as is the case by default, the GC keeps
1637 derivations---i.e., @file{.drv} files---as long as at least one of their
1638 outputs is live. This allows users to keep track of the origins of
1639 items in their store. Setting it to @code{no} saves a bit of disk
1642 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1643 liveness to flow from outputs to derivations, and setting
1644 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1645 derivations to outputs. When both are set to @code{yes}, the effect is
1646 to keep all the build prerequisites (the sources, compiler, libraries,
1647 and other build-time tools) of live objects in the store, regardless of
1648 whether these prerequisites are reachable from a GC root. This is
1649 convenient for developers since it saves rebuilds or downloads.
1651 @item --impersonate-linux-2.6
1652 On Linux-based systems, impersonate Linux 2.6. This means that the
1653 kernel's @command{uname} system call will report 2.6 as the release number.
1655 This might be helpful to build programs that (usually wrongfully) depend
1656 on the kernel version number.
1659 Do not keep build logs. By default they are kept under
1660 @file{@var{localstatedir}/guix/log}.
1662 @item --system=@var{system}
1663 Assume @var{system} as the current system type. By default it is the
1664 architecture/kernel pair found at configure time, such as
1665 @code{x86_64-linux}.
1667 @item --listen=@var{endpoint}
1668 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1669 as the file name of a Unix-domain socket if it starts with
1670 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1671 host name or host name and port to listen to. Here are a few examples:
1674 @item --listen=/gnu/var/daemon
1675 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1676 creating it if needed.
1678 @item --listen=localhost
1679 @cindex daemon, remote access
1680 @cindex remote access to the daemon
1681 @cindex daemon, cluster setup
1682 @cindex clusters, daemon setup
1683 Listen for TCP connections on the network interface corresponding to
1684 @code{localhost}, on port 44146.
1686 @item --listen=128.0.0.42:1234
1687 Listen for TCP connections on the network interface corresponding to
1688 @code{128.0.0.42}, on port 1234.
1691 This option can be repeated multiple times, in which case
1692 @command{guix-daemon} accepts connections on all the specified
1693 endpoints. Users can tell client commands what endpoint to connect to
1694 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1695 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1698 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1699 @option{--listen=@var{host}} is suitable on local networks, such as
1700 clusters, where only trusted nodes may connect to the build daemon. In
1701 other cases where remote access to the daemon is needed, we recommend
1702 using Unix-domain sockets along with SSH.
1705 When @option{--listen} is omitted, @command{guix-daemon} listens for
1706 connections on the Unix-domain socket located at
1707 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1711 @node Application Setup
1712 @section Application Setup
1714 @cindex foreign distro
1715 When using Guix on top of GNU/Linux distribution other than Guix System---a
1716 so-called @dfn{foreign distro}---a few additional steps are needed to
1717 get everything in place. Here are some of them.
1721 @anchor{locales-and-locpath}
1722 @cindex locales, when not on Guix System
1724 @vindex GUIX_LOCPATH
1725 Packages installed @i{via} Guix will not use the locale data of the
1726 host system. Instead, you must first install one of the locale packages
1727 available with Guix and then define the @env{GUIX_LOCPATH} environment
1731 $ guix install glibc-locales
1732 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1735 Note that the @code{glibc-locales} package contains data for all the
1736 locales supported by the GNU@tie{}libc and weighs in at around
1737 917@tie{}MiB. Alternatively, the @code{glibc-utf8-locales} is smaller but
1738 limited to a few UTF-8 locales.
1740 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1741 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1742 Manual}). There are two important differences though:
1746 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1747 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1748 to make sure the programs of the foreign distro will not end up loading
1749 incompatible locale data.
1752 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1753 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1754 should your Guix profile contain a mixture of programs linked against
1755 different libc version, each libc version will only try to load locale
1756 data in the right format.
1759 This is important because the locale data format used by different libc
1760 versions may be incompatible.
1762 @subsection Name Service Switch
1764 @cindex name service switch, glibc
1765 @cindex NSS (name service switch), glibc
1766 @cindex nscd (name service caching daemon)
1767 @cindex name service caching daemon (nscd)
1768 When using Guix on a foreign distro, we @emph{strongly recommend} that
1769 the system run the GNU C library's @dfn{name service cache daemon},
1770 @command{nscd}, which should be listening on the
1771 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1772 installed with Guix may fail to look up host names or user accounts, or
1773 may even crash. The next paragraphs explain why.
1775 @cindex @file{nsswitch.conf}
1776 The GNU C library implements a @dfn{name service switch} (NSS), which is
1777 an extensible mechanism for ``name lookups'' in general: host name
1778 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1779 The GNU C Library Reference Manual}).
1781 @cindex Network information service (NIS)
1782 @cindex NIS (Network information service)
1783 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1784 lookup implementations: for example, the @code{nss-mdns} plugin allow
1785 resolution of @code{.local} host names, the @code{nis} plugin allows
1786 user account lookup using the Network information service (NIS), and so
1787 on. These extra ``lookup services'' are configured system-wide in
1788 @file{/etc/nsswitch.conf}, and all the programs running on the system
1789 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1792 When they perform a name lookup---for instance by calling the
1793 @code{getaddrinfo} function in C---applications first try to connect to
1794 the nscd; on success, nscd performs name lookups on their behalf. If
1795 the nscd is not running, then they perform the name lookup by
1796 themselves, by loading the name lookup services into their own address
1797 space and running it. These name lookup services---the
1798 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1799 the host system's C library, rather than from the C library the
1800 application is linked against (the C library coming from Guix).
1802 And this is where the problem is: if your application is linked against
1803 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1804 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1805 likely crash or have its name lookups fail unexpectedly.
1807 Running @command{nscd} on the system, among other advantages, eliminates
1808 this binary incompatibility problem because those @code{libnss_*.so}
1809 files are loaded in the @command{nscd} process, not in applications
1812 @subsection X11 Fonts
1815 The majority of graphical applications use Fontconfig to locate and
1816 load fonts and perform X11-client-side rendering. The @code{fontconfig}
1817 package in Guix looks for fonts in @file{$HOME/.guix-profile}
1818 by default. Thus, to allow graphical applications installed with Guix
1819 to display fonts, you have to install fonts with Guix as well.
1820 Essential font packages include @code{gs-fonts}, @code{font-dejavu}, and
1821 @code{font-gnu-freefont}.
1823 @cindex @code{fc-cache}
1825 Once you have installed or removed fonts, or when you notice an
1826 application that does not find fonts, you may need to install Fontconfig
1827 and to force an update of its font cache by running:
1830 guix install fontconfig
1834 To display text written in Chinese languages, Japanese, or Korean in
1835 graphical applications, consider installing
1836 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
1837 has multiple outputs, one per language family (@pxref{Packages with
1838 Multiple Outputs}). For instance, the following command installs fonts
1839 for Chinese languages:
1842 guix install font-adobe-source-han-sans:cn
1845 @cindex @code{xterm}
1846 Older programs such as @command{xterm} do not use Fontconfig and instead
1847 rely on server-side font rendering. Such programs require to specify a
1848 full name of a font using XLFD (X Logical Font Description), like this:
1851 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
1854 To be able to use such full names for the TrueType fonts installed in
1855 your Guix profile, you need to extend the font path of the X server:
1857 @c Note: 'xset' does not accept symlinks so the trick below arranges to
1858 @c get at the real directory. See <https://bugs.gnu.org/30655>.
1860 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
1863 @cindex @code{xlsfonts}
1864 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
1865 to make sure your TrueType fonts are listed there.
1868 @subsection X.509 Certificates
1870 @cindex @code{nss-certs}
1871 The @code{nss-certs} package provides X.509 certificates, which allow
1872 programs to authenticate Web servers accessed over HTTPS.
1874 When using Guix on a foreign distro, you can install this package and
1875 define the relevant environment variables so that packages know where to
1876 look for certificates. @xref{X.509 Certificates}, for detailed
1879 @subsection Emacs Packages
1881 @cindex @code{emacs}
1882 When you install Emacs packages with Guix, the Elisp files are placed
1883 under the @file{share/emacs/site-lisp/} directory of the profile in
1884 which they are installed. The Elisp libraries are made available to
1885 Emacs through the @env{EMACSLOADPATH} environment variable, which is
1886 set when installing Emacs itself.
1888 Additionally, autoload definitions are automatically evaluated at the
1889 initialization of Emacs, by the Guix-specific
1890 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
1891 want to avoid auto-loading the Emacs packages installed with Guix, you
1892 can do so by running Emacs with the @option{--no-site-file} option
1893 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
1896 @node Upgrading Guix
1897 @section Upgrading Guix
1899 @cindex Upgrading Guix, on a foreign distro
1901 To upgrade Guix, run:
1907 @xref{Invoking guix pull}, for more information.
1909 @cindex upgrading Guix for the root user, on a foreign distro
1910 @cindex upgrading the Guix daemon, on a foreign distro
1911 @cindex @command{guix pull} for the root user, on a foreign distro
1913 On a foreign distro, you can upgrade the build daemon by running:
1920 followed by (assuming your distro uses the systemd service management
1924 systemctl restart guix-daemon.service
1927 On Guix System, upgrading the daemon is achieved by reconfiguring the
1928 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
1932 @c *********************************************************************
1933 @node System Installation
1934 @chapter System Installation
1936 @cindex installing Guix System
1937 @cindex Guix System, installation
1938 This section explains how to install Guix System
1939 on a machine. Guix, as a package manager, can
1940 also be installed on top of a running GNU/Linux system,
1941 @pxref{Installation}.
1945 @c This paragraph is for people reading this from tty2 of the
1946 @c installation image.
1947 You are reading this documentation with an Info reader. For details on
1948 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
1949 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
1950 Info}. Hit @kbd{l} afterwards to come back here.
1952 Alternatively, run @command{info info} in another tty to keep the manual
1958 * Limitations:: What you can expect.
1959 * Hardware Considerations:: Supported hardware.
1960 * USB Stick and DVD Installation:: Preparing the installation medium.
1961 * Preparing for Installation:: Networking, partitioning, etc.
1962 * Guided Graphical Installation:: Easy graphical installation.
1963 * Manual Installation:: Manual installation for wizards.
1964 * After System Installation:: When installation succeeded.
1965 * Installing Guix in a VM:: Guix System playground.
1966 * Building the Installation Image:: How this comes to be.
1970 @section Limitations
1972 We consider Guix System to be ready for a wide range of ``desktop'' and server
1973 use cases. The reliability guarantees it provides---transactional upgrades
1974 and rollbacks, reproducibility---make it a solid foundation.
1976 Nevertheless, before you proceed with the installation, be aware of the
1977 following noteworthy limitations applicable to version @value{VERSION}:
1981 More and more system services are provided (@pxref{Services}), but some
1985 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
1986 as well as a number of X11 window managers. However, KDE is currently
1990 More than a disclaimer, this is an invitation to report issues (and success
1991 stories!), and to join us in improving it. @xref{Contributing}, for more
1995 @node Hardware Considerations
1996 @section Hardware Considerations
1998 @cindex hardware support on Guix System
1999 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
2000 builds around the kernel Linux-libre, which means that only hardware for
2001 which free software drivers and firmware exist is supported. Nowadays,
2002 a wide range of off-the-shelf hardware is supported on
2003 GNU/Linux-libre---from keyboards to graphics cards to scanners and
2004 Ethernet controllers. Unfortunately, there are still areas where
2005 hardware vendors deny users control over their own computing, and such
2006 hardware is not supported on Guix System.
2008 @cindex WiFi, hardware support
2009 One of the main areas where free drivers or firmware are lacking is WiFi
2010 devices. WiFi devices known to work include those using Atheros chips
2011 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
2012 driver, and those using Broadcom/AirForce chips (BCM43xx with
2013 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
2014 Linux-libre driver. Free firmware exists for both and is available
2015 out-of-the-box on Guix System, as part of @code{%base-firmware}
2016 (@pxref{operating-system Reference, @code{firmware}}).
2018 @cindex RYF, Respects Your Freedom
2019 The @uref{https://www.fsf.org/, Free Software Foundation} runs
2020 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
2021 certification program for hardware products that respect your freedom
2022 and your privacy and ensure that you have control over your device. We
2023 encourage you to check the list of RYF-certified devices.
2025 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
2026 web site. It contains a catalog of hardware devices with information
2027 about their support in GNU/Linux.
2030 @node USB Stick and DVD Installation
2031 @section USB Stick and DVD Installation
2033 An ISO-9660 installation image that can be written to a USB stick or
2034 burnt to a DVD can be downloaded from
2035 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz},
2036 where you can replace @code{x86_64-linux} with one of:
2040 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
2043 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
2046 @c start duplication of authentication part from ``Binary Installation''
2047 Make sure to download the associated @file{.sig} file and to verify the
2048 authenticity of the image against it, along these lines:
2051 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
2052 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.xz.sig
2055 If that command fails because you do not have the required public key,
2056 then run this command to import it:
2059 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
2060 -qO - | gpg --import -
2064 and rerun the @code{gpg --verify} command.
2066 Take note that a warning like ``This key is not certified with a trusted
2067 signature!'' is normal.
2071 This image contains the tools necessary for an installation.
2072 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
2074 @unnumberedsubsec Copying to a USB Stick
2076 To copy the image to a USB stick, follow these steps:
2080 Decompress the image using the @command{xz} command:
2083 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
2087 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
2088 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
2089 copy the image with:
2092 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX status=progress
2096 Access to @file{/dev/sdX} usually requires root privileges.
2099 @unnumberedsubsec Burning on a DVD
2101 To copy the image to a DVD, follow these steps:
2105 Decompress the image using the @command{xz} command:
2108 xz -d guix-system-install-@value{VERSION}.x86_64-linux.iso.xz
2112 Insert a blank DVD into your machine, and determine
2113 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
2114 copy the image with:
2117 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
2120 Access to @file{/dev/srX} usually requires root privileges.
2123 @unnumberedsubsec Booting
2125 Once this is done, you should be able to reboot the system and boot from
2126 the USB stick or DVD. The latter usually requires you to get in the
2127 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2128 In order to boot from Libreboot, switch to the command mode by pressing
2129 the @kbd{c} key and type @command{search_grub usb}.
2131 @xref{Installing Guix in a VM}, if, instead, you would like to install
2132 Guix System in a virtual machine (VM).
2135 @node Preparing for Installation
2136 @section Preparing for Installation
2138 Once you have booted, you can use the guided graphical installer, which makes
2139 it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
2140 if you are already familiar with GNU/Linux and if you want more control than
2141 what the graphical installer provides, you can choose the ``manual''
2142 installation process (@pxref{Manual Installation}).
2144 The graphical installer is available on TTY1. You can obtain root shells on
2145 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2146 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2147 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2148 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2149 which allows you to select text with the left mouse button and to paste it
2150 with the middle button.
2153 Installation requires access to the Internet so that any missing
2154 dependencies of your system configuration can be downloaded. See the
2155 ``Networking'' section below.
2158 @node Guided Graphical Installation
2159 @section Guided Graphical Installation
2161 The graphical installer is a text-based user interface. It will guide you,
2162 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2164 The first dialog boxes allow you to set up the system as you use it during the
2165 installation: you can choose the language, keyboard layout, and set up
2166 networking, which will be used during the installation. The image below shows
2167 the networking dialog.
2169 @image{images/installer-network,5in,, networking setup with the graphical installer}
2171 Later steps allow you to partition your hard disk, as shown in the image
2172 below, to choose whether or not to use encrypted file systems, to enter the
2173 host name and root password, and to create an additional account, among other
2176 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2178 Note that, at any time, the installer allows you to exit the current
2179 installation step and resume at a previous step, as show in the image below.
2181 @image{images/installer-resume,5in,, resuming the installation process}
2183 Once you're done, the installer produces an operating system configuration and
2184 displays it (@pxref{Using the Configuration System}). At that point you can
2185 hit ``OK'' and installation will proceed. On success, you can reboot into the
2186 new system and enjoy. @xref{After System Installation}, for what's next!
2189 @node Manual Installation
2190 @section Manual Installation
2192 This section describes how you would ``manually'' install GNU@tie{}Guix System
2193 on your machine. This option requires familiarity with GNU/Linux, with the
2194 shell, and with common administration tools. If you think this is not for
2195 you, consider using the guided graphical installer (@pxref{Guided Graphical
2198 The installation system provides root shells on TTYs 3 to 6; press
2199 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2200 many common tools needed to install the system. But it is also a full-blown
2201 Guix System, which means that you can install additional packages, should you
2202 need it, using @command{guix package} (@pxref{Invoking guix package}).
2205 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2206 * Proceeding with the Installation:: Installing.
2209 @node Keyboard Layout and Networking and Partitioning
2210 @subsection Keyboard Layout, Networking, and Partitioning
2212 Before you can install the system, you may want to adjust the keyboard layout,
2213 set up networking, and partition your target hard disk. This section will
2214 guide you through this.
2216 @subsubsection Keyboard Layout
2218 @cindex keyboard layout
2219 The installation image uses the US qwerty keyboard layout. If you want
2220 to change it, you can use the @command{loadkeys} command. For example,
2221 the following command selects the Dvorak keyboard layout:
2227 See the files under @file{/run/current-system/profile/share/keymaps} for
2228 a list of available keyboard layouts. Run @command{man loadkeys} for
2231 @subsubsection Networking
2233 Run the following command to see what your network interfaces are called:
2240 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2246 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2247 Wired interfaces have a name starting with @samp{e}; for example, the
2248 interface corresponding to the first on-board Ethernet controller is
2249 called @samp{eno1}. Wireless interfaces have a name starting with
2250 @samp{w}, like @samp{w1p2s0}.
2253 @item Wired connection
2254 To configure a wired network run the following command, substituting
2255 @var{interface} with the name of the wired interface you want to use.
2258 ifconfig @var{interface} up
2262 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2265 ip link set @var{interface} up
2268 @item Wireless connection
2271 To configure wireless networking, you can create a configuration file
2272 for the @command{wpa_supplicant} configuration tool (its location is not
2273 important) using one of the available text editors such as
2277 nano wpa_supplicant.conf
2280 As an example, the following stanza can go to this file and will work
2281 for many wireless networks, provided you give the actual SSID and
2282 passphrase for the network you are connecting to:
2286 ssid="@var{my-ssid}"
2288 psk="the network's secret passphrase"
2292 Start the wireless service and run it in the background with the
2293 following command (substitute @var{interface} with the name of the
2294 network interface you want to use):
2297 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2300 Run @command{man wpa_supplicant} for more information.
2304 At this point, you need to acquire an IP address. On a network where IP
2305 addresses are automatically assigned @i{via} DHCP, you can run:
2308 dhclient -v @var{interface}
2311 Try to ping a server to see if networking is up and running:
2317 Setting up network access is almost always a requirement because the
2318 image does not contain all the software and tools that may be needed.
2320 @cindex proxy, during system installation
2321 If you need HTTP and HTTPS access to go through a proxy, run the
2325 herd set-http-proxy guix-daemon @var{URL}
2329 where @var{URL} is the proxy URL, for example
2330 @code{http://example.org:8118}.
2332 @cindex installing over SSH
2333 If you want to, you can continue the installation remotely by starting
2337 herd start ssh-daemon
2340 Make sure to either set a password with @command{passwd}, or configure
2341 OpenSSH public key authentication before logging in.
2343 @subsubsection Disk Partitioning
2345 Unless this has already been done, the next step is to partition, and
2346 then format the target partition(s).
2348 The installation image includes several partitioning tools, including
2349 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2350 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2351 the partition layout you want:
2357 If your disk uses the GUID Partition Table (GPT) format and you plan to
2358 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2359 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2362 @cindex EFI, installation
2363 @cindex UEFI, installation
2364 @cindex ESP, EFI system partition
2365 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2366 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2367 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2370 parted /dev/sda set 1 esp on
2374 @vindex grub-bootloader
2375 @vindex grub-efi-bootloader
2376 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2377 @file{/sys/firmware/efi} exists in the installation image, then you should
2378 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2379 Otherwise you should use the BIOS-based GRUB, known as
2380 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2384 Once you are done partitioning the target hard disk drive, you have to
2385 create a file system on the relevant partition(s)@footnote{Currently
2386 Guix System only supports ext4, btrfs, JFS, and F2FS file systems. In
2387 particular, code that reads file system UUIDs and labels only works for these
2388 file system types.}. For the ESP, if you have one and assuming it is
2389 @file{/dev/sda1}, run:
2392 mkfs.fat -F32 /dev/sda1
2395 For the root file system, ext4 is the most widely used format. Other
2396 file systems, such as Btrfs, support compression, which is reported to
2397 nicely complement file deduplication that the daemon performs
2398 independently of the file system (@pxref{Invoking guix-daemon,
2401 Preferably, assign file systems a label so that you can easily and
2402 reliably refer to them in @code{file-system} declarations (@pxref{File
2403 Systems}). This is typically done using the @code{-L} option of
2404 @command{mkfs.ext4} and related commands. So, assuming the target root
2405 partition lives at @file{/dev/sda2}, a file system with the label
2406 @code{my-root} can be created with:
2409 mkfs.ext4 -L my-root /dev/sda2
2412 @cindex encrypted disk
2413 If you are instead planning to encrypt the root partition, you can use
2414 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2415 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2416 @code{man cryptsetup}} for more information). Assuming you want to
2417 store the root partition on @file{/dev/sda2}, the command sequence would
2418 be along these lines:
2421 cryptsetup luksFormat /dev/sda2
2422 cryptsetup open --type luks /dev/sda2 my-partition
2423 mkfs.ext4 -L my-root /dev/mapper/my-partition
2426 Once that is done, mount the target file system under @file{/mnt}
2427 with a command like (again, assuming @code{my-root} is the label of the
2431 mount LABEL=my-root /mnt
2434 Also mount any other file systems you would like to use on the target
2435 system relative to this path. If you have opted for @file{/boot/efi} as an
2436 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2437 found by @code{guix system init} afterwards.
2439 Finally, if you plan to use one or more swap partitions (@pxref{Memory
2440 Concepts, swap space,, libc, The GNU C Library Reference Manual}), make
2441 sure to initialize them with @command{mkswap}. Assuming you have one
2442 swap partition on @file{/dev/sda3}, you would run:
2449 Alternatively, you may use a swap file. For example, assuming that in
2450 the new system you want to use the file @file{/swapfile} as a swap file,
2451 you would run@footnote{This example will work for many types of file
2452 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2453 btrfs), the required steps may be different. For details, see the
2454 manual pages for @command{mkswap} and @command{swapon}.}:
2457 # This is 10 GiB of swap space. Adjust "count" to change the size.
2458 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2459 # For security, make the file readable and writable only by root.
2460 chmod 600 /mnt/swapfile
2461 mkswap /mnt/swapfile
2462 swapon /mnt/swapfile
2465 Note that if you have encrypted the root partition and created a swap
2466 file in its file system as described above, then the encryption also
2467 protects the swap file, just like any other file in that file system.
2469 @node Proceeding with the Installation
2470 @subsection Proceeding with the Installation
2472 With the target partitions ready and the target root mounted on
2473 @file{/mnt}, we're ready to go. First, run:
2476 herd start cow-store /mnt
2479 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2480 during the installation phase are written to the target disk on @file{/mnt}
2481 rather than kept in memory. This is necessary because the first phase of
2482 the @command{guix system init} command (see below) entails downloads or
2483 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2485 Next, you have to edit a file and
2486 provide the declaration of the operating system to be installed. To
2487 that end, the installation system comes with three text editors. We
2488 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2489 supports syntax highlighting and parentheses matching; other editors
2490 include GNU Zile (an Emacs clone), and
2491 nvi (a clone of the original BSD @command{vi} editor).
2492 We strongly recommend storing that file on the target root file system, say,
2493 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2494 configuration file once you have rebooted into the newly-installed system.
2496 @xref{Using the Configuration System}, for an overview of the
2497 configuration file. The example configurations discussed in that
2498 section are available under @file{/etc/configuration} in the
2499 installation image. Thus, to get started with a system configuration
2500 providing a graphical display server (a ``desktop'' system), you can run
2501 something along these lines:
2505 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2506 # nano /mnt/etc/config.scm
2509 You should pay attention to what your configuration file contains, and
2514 Make sure the @code{bootloader-configuration} form refers to the target
2515 you want to install GRUB on. It should mention @code{grub-bootloader} if
2516 you are installing GRUB in the legacy way, or @code{grub-efi-bootloader}
2517 for newer UEFI systems. For legacy systems, the @code{target} field
2518 names a device, like @code{/dev/sda}; for UEFI systems it names a path
2519 to a mounted EFI partition, like @code{/boot/efi}; do make sure the path is
2520 currently mounted and a @code{file-system} entry is specified in your
2524 Be sure that your file system labels match the value of their respective
2525 @code{device} fields in your @code{file-system} configuration, assuming
2526 your @code{file-system} configuration uses the @code{file-system-label}
2527 procedure in its @code{device} field.
2530 If there are encrypted or RAID partitions, make sure to add a
2531 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2534 Once you are done preparing the configuration file, the new system must
2535 be initialized (remember that the target root file system is mounted
2539 guix system init /mnt/etc/config.scm /mnt
2543 This copies all the necessary files and installs GRUB on
2544 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2545 more information, @pxref{Invoking guix system}. This command may trigger
2546 downloads or builds of missing packages, which can take some time.
2548 Once that command has completed---and hopefully succeeded!---you can run
2549 @command{reboot} and boot into the new system. The @code{root} password
2550 in the new system is initially empty; other users' passwords need to be
2551 initialized by running the @command{passwd} command as @code{root},
2552 unless your configuration specifies otherwise
2553 (@pxref{user-account-password, user account passwords}).
2554 @xref{After System Installation}, for what's next!
2557 @node After System Installation
2558 @section After System Installation
2560 Success, you've now booted into Guix System! From then on, you can update the
2561 system whenever you want by running, say:
2565 sudo guix system reconfigure /etc/config.scm
2569 This builds a new system generation with the latest packages and services
2570 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2571 your system includes the latest security updates (@pxref{Security Updates}).
2573 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2575 @cindex sudo vs. @command{guix pull}
2576 Note that @command{sudo guix} runs your user's @command{guix} command and
2577 @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
2578 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2580 The difference matters here, because @command{guix pull} updates
2581 the @command{guix} command and package definitions only for the user it is ran
2582 as. This means that if you choose to use @command{guix system reconfigure} in
2583 root's login shell, you'll need to @command{guix pull} separately.
2586 Now, @pxref{Getting Started}, and
2587 join us on @code{#guix} on the Freenode IRC network or on
2588 @email{guix-devel@@gnu.org} to share your experience!
2591 @node Installing Guix in a VM
2592 @section Installing Guix in a Virtual Machine
2594 @cindex virtual machine, Guix System installation
2595 @cindex virtual private server (VPS)
2596 @cindex VPS (virtual private server)
2597 If you'd like to install Guix System in a virtual machine (VM) or on a
2598 virtual private server (VPS) rather than on your beloved machine, this
2601 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2602 disk image, follow these steps:
2606 First, retrieve and decompress the Guix system installation image as
2607 described previously (@pxref{USB Stick and DVD Installation}).
2610 Create a disk image that will hold the installed system. To make a
2611 qcow2-formatted disk image, use the @command{qemu-img} command:
2614 qemu-img create -f qcow2 guix-system.img 50G
2617 The resulting file will be much smaller than 50 GB (typically less than
2618 1 MB), but it will grow as the virtualized storage device is filled up.
2621 Boot the USB installation image in an VM:
2624 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2625 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2626 -drive file=guix-system.img \
2627 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2630 @code{-enable-kvm} is optional, but significantly improves performance,
2631 @pxref{Running Guix in a VM}.
2634 You're now root in the VM, proceed with the installation process.
2635 @xref{Preparing for Installation}, and follow the instructions.
2638 Once installation is complete, you can boot the system that's on your
2639 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2642 @node Building the Installation Image
2643 @section Building the Installation Image
2645 @cindex installation image
2646 The installation image described above was built using the @command{guix
2647 system} command, specifically:
2650 guix system disk-image -t iso9660 gnu/system/install.scm
2653 Have a look at @file{gnu/system/install.scm} in the source tree,
2654 and see also @ref{Invoking guix system} for more information
2655 about the installation image.
2657 @section Building the Installation Image for ARM Boards
2659 Many ARM boards require a specific variant of the
2660 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2662 If you build a disk image and the bootloader is not available otherwise
2663 (on another boot drive etc), it's advisable to build an image that
2664 includes the bootloader, specifically:
2667 guix system disk-image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2670 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2671 board, a list of possible boards will be printed.
2673 @c *********************************************************************
2674 @node Getting Started
2675 @chapter Getting Started
2677 Presumably, you've reached this section because either you have
2678 installed Guix on top of another distribution (@pxref{Installation}), or
2679 you've installed the standalone Guix System (@pxref{System
2680 Installation}). It's time for you to get started using Guix and this
2681 section aims to help you do that and give you a feel of what it's like.
2683 Guix is about installing software, so probably the first thing you'll
2684 want to do is to actually look for software. Let's say you're looking
2685 for a text editor, you can run:
2688 guix search text editor
2691 This command shows you a number of matching @dfn{packages}, each time
2692 showing the package's name, version, a description, and additional info.
2693 Once you've found out the one you want to use, let's say Emacs (ah ha!),
2694 you can go ahead and install it (run this command as a regular user,
2695 @emph{no need for root privileges}!):
2701 You've installed your first package, congrats! In the process, you've
2702 probably noticed that Guix downloaded pre-built binaries; or, if you
2703 explicitly chose to @emph{not} use pre-built binaries, then probably
2704 Guix is still building software (@pxref{Substitutes}, for more info).
2706 Unless you're using Guix System, the @command{guix install} command must
2707 have printed this hint:
2710 hint: Consider setting the necessary environment variables by running:
2712 GUIX_PROFILE="$HOME/.guix-profile"
2713 . "$GUIX_PROFILE/etc/profile"
2715 Alternately, see `guix package --search-paths -p "$HOME/.guix-profile"'.
2718 Indeed, you must now tell your shell where @command{emacs} and other
2719 programs installed with Guix are to be found. Pasting the two lines
2720 above will do just that: it will add
2721 @code{$HOME/.guix-profile/bin}---which is where the installed package
2722 is---to the @code{PATH} environment variable. You can paste these two
2723 lines in your shell so they take effect right away, but more importantly
2724 you should add them to @file{~/.bash_profile} (or equivalent file if you
2725 do not use Bash) so that environment variables are set next time you
2726 spawn a shell. You only need to do this once and other search paths
2727 environment variables will be taken care of similarly---e.g., if you
2728 eventually install @code{python} and Python libraries, @code{PYTHONPATH}
2731 You can go on installing packages at your will. To list installed
2735 guix package --list-installed
2738 To remove a package, you would unsurprisingly run @command{guix remove}.
2739 A distinguishing feature is the ability to @dfn{roll back} any operation
2740 you made---installation, removal, upgrade---by simply typing:
2743 guix package --roll-back
2746 This is because each operation is in fact a @dfn{transaction} that
2747 creates a new @dfn{generation}. These generations and the difference
2748 between them can be displayed by running:
2751 guix package --list-generations
2754 Now you know the basics of package management!
2756 @quotation Going further
2757 @xref{Package Management}, for more about package management. You may
2758 like @dfn{declarative} package management with @command{guix package
2759 --manifest}, managing separate @dfn{profiles} with @option{--profile},
2760 deleting old generations, collecting garbage, and other nifty features
2761 that will come in handy as you become more familiar with Guix. If you
2762 are a developer, @pxref{Development} for additional tools. And if
2763 you're curious, @pxref{Features}, to peek under the hood.
2766 Once you've installed a set of packages, you will want to periodically
2767 @emph{upgrade} them to the latest and greatest version. To do that, you
2768 will first pull the latest revision of Guix and its package collection:
2774 The end result is a new @command{guix} command, under
2775 @file{~/.config/guix/current/bin}. Unless you're on Guix System, the
2776 first time you run @command{guix pull}, be sure to follow the hint that
2777 the command prints and, similar to what we saw above, paste these two
2778 lines in your terminal and @file{.bash_profile}:
2781 GUIX_PROFILE="$HOME/.config/guix/current/etc/profile"
2782 . "$GUIX_PROFILE/etc/profile"
2786 You must also instruct your shell to point to this new @command{guix}:
2792 At this point, you're running a brand new Guix. You can thus go ahead
2793 and actually upgrade all the packages you previously installed:
2799 As you run this command, you will see that binaries are downloaded (or
2800 perhaps some packages are built), and eventually you end up with the
2801 upgraded packages. Should one of these upgraded packages not be to your
2802 liking, remember you can always roll back!
2804 You can display the exact revision of Guix you're currently using by
2811 The information it displays is @emph{all it takes to reproduce the exact
2812 same Guix}, be it at a different point in time or on a different
2815 @quotation Going further
2816 @xref{Invoking guix pull}, for more information. @xref{Channels}, on
2817 how to specify additional @dfn{channels} to pull packages from, how to
2818 replicate Guix, and more. You may also find @command{time-machine}
2819 handy (@pxref{Invoking guix time-machine}).
2822 If you installed Guix System, one of the first things you'll want to do
2823 is to upgrade your system. Once you've run @command{guix pull} to get
2824 the latest Guix, you can upgrade the system like this:
2827 sudo guix system reconfigure /etc/config.scm
2830 Upon completion, the system runs the latest versions of its software
2831 packages. When you eventually reboot, you'll notice a sub-menu in the
2832 bootloader that reads ``Old system generations'': it's what allows you
2833 to boot @emph{an older generation of your system}, should the latest
2834 generation be ``broken'' or otherwise unsatisfying. Just like for
2835 packages, you can always @emph{roll back} to a previous generation
2836 @emph{of the whole system}:
2839 sudo guix system roll-back
2842 There are many things you'll probably want to tweak on your system:
2843 adding new user accounts, adding new system services, fiddling with the
2844 configuration of those services, etc. The system configuration is
2845 @emph{entirely} described in the @file{/etc/config.scm} file.
2846 @xref{Using the Configuration System}, to learn how to change it.
2848 Now you know enough to get started!
2850 @quotation Resources
2851 The rest of this manual provides a reference for all things Guix. Here
2852 are some additional resources you may find useful:
2856 @xref{Top,,, guix-cookbook, The GNU Guix Cookbook}, for a list of
2857 ``how-to'' style of recipes for a variety of applications.
2860 The @uref{https://guix.gnu.org/guix-refcard.pdf, GNU Guix Reference
2861 Card} lists in two pages most of the commands and options you'll ever
2865 The web site contains @uref{https://guix.gnu.org/en/videos/,
2866 instructional videos} covering topics such as everyday use of Guix, how
2867 to get help, and how to become a contributor.
2870 @xref{Documentation}, to learn how to access documentation on your
2874 We hope you will enjoy Guix as much as the community enjoys building it!
2877 @c *********************************************************************
2878 @node Package Management
2879 @chapter Package Management
2882 The purpose of GNU Guix is to allow users to easily install, upgrade, and
2883 remove software packages, without having to know about their build
2884 procedures or dependencies. Guix also goes beyond this obvious set of
2887 This chapter describes the main features of Guix, as well as the
2888 package management tools it provides. Along with the command-line
2889 interface described below (@pxref{Invoking guix package, @code{guix
2890 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
2891 emacs-guix, The Emacs-Guix Reference Manual}), after installing
2892 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
2896 guix install emacs-guix
2900 * Features:: How Guix will make your life brighter.
2901 * Invoking guix package:: Package installation, removal, etc.
2902 * Substitutes:: Downloading pre-built binaries.
2903 * Packages with Multiple Outputs:: Single source package, multiple outputs.
2904 * Invoking guix gc:: Running the garbage collector.
2905 * Invoking guix pull:: Fetching the latest Guix and distribution.
2906 * Invoking guix time-machine:: Running an older revision of Guix.
2907 * Inferiors:: Interacting with another revision of Guix.
2908 * Invoking guix describe:: Display information about your Guix revision.
2909 * Invoking guix archive:: Exporting and importing store files.
2915 Here we assume you've already made your first steps with Guix
2916 (@pxref{Getting Started}) and would like to get an overview about what's
2917 going on under the hood.
2919 When using Guix, each package ends up in the @dfn{package store}, in its
2920 own directory---something that resembles
2921 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
2923 Instead of referring to these directories, users have their own
2924 @dfn{profile}, which points to the packages that they actually want to
2925 use. These profiles are stored within each user's home directory, at
2926 @code{$HOME/.guix-profile}.
2928 For example, @code{alice} installs GCC 4.7.2. As a result,
2929 @file{/home/alice/.guix-profile/bin/gcc} points to
2930 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
2931 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
2932 simply continues to point to
2933 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
2934 coexist on the same system without any interference.
2936 The @command{guix package} command is the central tool to manage
2937 packages (@pxref{Invoking guix package}). It operates on the per-user
2938 profiles, and can be used @emph{with normal user privileges}.
2940 @cindex transactions
2941 The command provides the obvious install, remove, and upgrade
2942 operations. Each invocation is actually a @emph{transaction}: either
2943 the specified operation succeeds, or nothing happens. Thus, if the
2944 @command{guix package} process is terminated during the transaction,
2945 or if a power outage occurs during the transaction, then the user's
2946 profile remains in its previous state, and remains usable.
2948 In addition, any package transaction may be @emph{rolled back}. So, if,
2949 for example, an upgrade installs a new version of a package that turns
2950 out to have a serious bug, users may roll back to the previous instance
2951 of their profile, which was known to work well. Similarly, the global
2952 system configuration on Guix is subject to
2953 transactional upgrades and roll-back
2954 (@pxref{Using the Configuration System}).
2956 All packages in the package store may be @emph{garbage-collected}.
2957 Guix can determine which packages are still referenced by user
2958 profiles, and remove those that are provably no longer referenced
2959 (@pxref{Invoking guix gc}). Users may also explicitly remove old
2960 generations of their profile so that the packages they refer to can be
2963 @cindex reproducibility
2964 @cindex reproducible builds
2965 Guix takes a @dfn{purely functional} approach to package
2966 management, as described in the introduction (@pxref{Introduction}).
2967 Each @file{/gnu/store} package directory name contains a hash of all the
2968 inputs that were used to build that package---compiler, libraries, build
2969 scripts, etc. This direct correspondence allows users to make sure a
2970 given package installation matches the current state of their
2971 distribution. It also helps maximize @dfn{build reproducibility}:
2972 thanks to the isolated build environments that are used, a given build
2973 is likely to yield bit-identical files when performed on different
2974 machines (@pxref{Invoking guix-daemon, container}).
2977 This foundation allows Guix to support @dfn{transparent binary/source
2978 deployment}. When a pre-built binary for a @file{/gnu/store} item is
2979 available from an external source---a @dfn{substitute}, Guix just
2980 downloads it and unpacks it;
2981 otherwise, it builds the package from source, locally
2982 (@pxref{Substitutes}). Because build results are usually bit-for-bit
2983 reproducible, users do not have to trust servers that provide
2984 substitutes: they can force a local build and @emph{challenge} providers
2985 (@pxref{Invoking guix challenge}).
2987 Control over the build environment is a feature that is also useful for
2988 developers. The @command{guix environment} command allows developers of
2989 a package to quickly set up the right development environment for their
2990 package, without having to manually install the dependencies of the
2991 package into their profile (@pxref{Invoking guix environment}).
2993 @cindex replication, of software environments
2994 @cindex provenance tracking, of software artifacts
2995 All of Guix and its package definitions is version-controlled, and
2996 @command{guix pull} allows you to ``travel in time'' on the history of Guix
2997 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
2998 Guix instance on a different machine or at a later point in time, which in
2999 turn allows you to @emph{replicate complete software environments}, while
3000 retaining precise @dfn{provenance tracking} of the software.
3002 @node Invoking guix package
3003 @section Invoking @command{guix package}
3005 @cindex installing packages
3006 @cindex removing packages
3007 @cindex package installation
3008 @cindex package removal
3009 The @command{guix package} command is the tool that allows users to
3010 install, upgrade, and remove packages, as well as rolling back to
3011 previous configurations. It operates only on the user's own profile,
3012 and works with normal user privileges (@pxref{Features}). Its syntax
3016 guix package @var{options}
3019 @cindex transactions
3020 Primarily, @var{options} specifies the operations to be performed during
3021 the transaction. Upon completion, a new profile is created, but
3022 previous @dfn{generations} of the profile remain available, should the user
3025 For example, to remove @code{lua} and install @code{guile} and
3026 @code{guile-cairo} in a single transaction:
3029 guix package -r lua -i guile guile-cairo
3032 @cindex aliases, for @command{guix package}
3033 For your convenience, we also provide the following aliases:
3037 @command{guix search} is an alias for @command{guix package -s},
3039 @command{guix install} is an alias for @command{guix package -i},
3041 @command{guix remove} is an alias for @command{guix package -r},
3043 @command{guix upgrade} is an alias for @command{guix package -u},
3045 and @command{guix show} is an alias for @command{guix package --show=}.
3048 These aliases are less expressive than @command{guix package} and provide
3049 fewer options, so in some cases you'll probably want to use @command{guix
3052 @command{guix package} also supports a @dfn{declarative approach}
3053 whereby the user specifies the exact set of packages to be available and
3054 passes it @i{via} the @option{--manifest} option
3055 (@pxref{profile-manifest, @option{--manifest}}).
3058 For each user, a symlink to the user's default profile is automatically
3059 created in @file{$HOME/.guix-profile}. This symlink always points to the
3060 current generation of the user's default profile. Thus, users can add
3061 @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
3062 variable, and so on.
3063 @cindex search paths
3064 If you are not using Guix System, consider adding the
3065 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
3066 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
3067 shells get all the right environment variable definitions:
3070 GUIX_PROFILE="$HOME/.guix-profile" ; \
3071 source "$HOME/.guix-profile/etc/profile"
3074 In a multi-user setup, user profiles are stored in a place registered as
3075 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
3076 to (@pxref{Invoking guix gc}). That directory is normally
3077 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
3078 @var{localstatedir} is the value passed to @code{configure} as
3079 @option{--localstatedir}, and @var{user} is the user name. The
3080 @file{per-user} directory is created when @command{guix-daemon} is
3081 started, and the @var{user} sub-directory is created by @command{guix
3084 The @var{options} can be among the following:
3088 @item --install=@var{package} @dots{}
3089 @itemx -i @var{package} @dots{}
3090 Install the specified @var{package}s.
3092 Each @var{package} may specify either a simple package name, such as
3093 @code{guile}, or a package name followed by an at-sign and version number,
3094 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
3095 case, the newest version prefixed by @code{1.8} is selected).
3097 If no version number is specified, the
3098 newest available version will be selected. In addition, @var{package}
3099 may contain a colon, followed by the name of one of the outputs of the
3100 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
3101 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
3102 name (and optionally version) are searched for among the GNU
3103 distribution modules (@pxref{Package Modules}).
3105 @cindex propagated inputs
3106 Sometimes packages have @dfn{propagated inputs}: these are dependencies
3107 that automatically get installed along with the required package
3108 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
3109 @code{package} objects}, for information about propagated inputs in
3110 package definitions).
3112 @anchor{package-cmd-propagated-inputs}
3113 An example is the GNU MPC library: its C header files refer to those of
3114 the GNU MPFR library, which in turn refer to those of the GMP library.
3115 Thus, when installing MPC, the MPFR and GMP libraries also get installed
3116 in the profile; removing MPC also removes MPFR and GMP---unless they had
3117 also been explicitly installed by the user.
3119 Besides, packages sometimes rely on the definition of environment
3120 variables for their search paths (see explanation of
3121 @option{--search-paths} below). Any missing or possibly incorrect
3122 environment variable definitions are reported here.
3124 @item --install-from-expression=@var{exp}
3126 Install the package @var{exp} evaluates to.
3128 @var{exp} must be a Scheme expression that evaluates to a
3129 @code{<package>} object. This option is notably useful to disambiguate
3130 between same-named variants of a package, with expressions such as
3131 @code{(@@ (gnu packages base) guile-final)}.
3133 Note that this option installs the first output of the specified
3134 package, which may be insufficient when needing a specific output of a
3135 multiple-output package.
3137 @item --install-from-file=@var{file}
3138 @itemx -f @var{file}
3139 Install the package that the code within @var{file} evaluates to.
3141 As an example, @var{file} might contain a definition like this
3142 (@pxref{Defining Packages}):
3145 @include package-hello.scm
3148 Developers may find it useful to include such a @file{guix.scm} file
3149 in the root of their project source tree that can be used to test
3150 development snapshots and create reproducible development environments
3151 (@pxref{Invoking guix environment}).
3153 The @var{file} may also contain a JSON representation of one or more
3154 package definitions. Running @code{guix package -f} on
3155 @file{hello.json} with the following contents would result in installing
3156 the package @code{greeter} after building @code{myhello}:
3159 @verbatiminclude package-hello.json
3162 @item --remove=@var{package} @dots{}
3163 @itemx -r @var{package} @dots{}
3164 Remove the specified @var{package}s.
3166 As for @option{--install}, each @var{package} may specify a version number
3167 and/or output name in addition to the package name. For instance,
3168 @samp{-r glibc:debug} would remove the @code{debug} output of
3171 @item --upgrade[=@var{regexp} @dots{}]
3172 @itemx -u [@var{regexp} @dots{}]
3173 @cindex upgrading packages
3174 Upgrade all the installed packages. If one or more @var{regexp}s are
3175 specified, upgrade only installed packages whose name matches a
3176 @var{regexp}. Also see the @option{--do-not-upgrade} option below.
3178 Note that this upgrades package to the latest version of packages found
3179 in the distribution currently installed. To update your distribution,
3180 you should regularly run @command{guix pull} (@pxref{Invoking guix
3183 @cindex package transformations, upgrades
3184 When upgrading, package transformations that were originally applied
3185 when creating the profile are automatically re-applied (@pxref{Package
3186 Transformation Options}). For example, assume you first installed Emacs
3187 from the tip of its development branch with:
3190 guix install emacs-next --with-branch=emacs-next=master
3193 Next time you run @command{guix upgrade}, Guix will again pull the tip
3194 of the Emacs development branch and build @code{emacs-next} from that
3197 Note that transformation options such as @option{--with-branch} and
3198 @option{--with-source} depend on external state; it is up to you to
3199 ensure that they work as expected. You can also discard a
3200 transformations that apply to a package by running:
3203 guix install @var{package}
3206 @item --do-not-upgrade[=@var{regexp} @dots{}]
3207 When used together with the @option{--upgrade} option, do @emph{not}
3208 upgrade any packages whose name matches a @var{regexp}. For example, to
3209 upgrade all packages in the current profile except those containing the
3210 substring ``emacs'':
3213 $ guix package --upgrade . --do-not-upgrade emacs
3216 @item @anchor{profile-manifest}--manifest=@var{file}
3217 @itemx -m @var{file}
3218 @cindex profile declaration
3219 @cindex profile manifest
3220 Create a new generation of the profile from the manifest object
3221 returned by the Scheme code in @var{file}. This option can be repeated
3222 several times, in which case the manifests are concatenated.
3224 This allows you to @emph{declare} the profile's contents rather than
3225 constructing it through a sequence of @option{--install} and similar
3226 commands. The advantage is that @var{file} can be put under version
3227 control, copied to different machines to reproduce the same profile, and
3230 @c FIXME: Add reference to (guix profile) documentation when available.
3231 @var{file} must return a @dfn{manifest} object, which is roughly a list
3234 @findex packages->manifest
3236 (use-package-modules guile emacs)
3241 ;; Use a specific package output.
3242 (list guile-2.0 "debug")))
3245 @findex specifications->manifest
3246 In this example we have to know which modules define the @code{emacs}
3247 and @code{guile-2.0} variables to provide the right
3248 @code{use-package-modules} line, which can be cumbersome. We can
3249 instead provide regular package specifications and let
3250 @code{specifications->manifest} look up the corresponding package
3254 (specifications->manifest
3255 '("emacs" "guile@@2.2" "guile@@2.2:debug"))
3259 @cindex rolling back
3260 @cindex undoing transactions
3261 @cindex transactions, undoing
3262 Roll back to the previous @dfn{generation} of the profile---i.e., undo
3263 the last transaction.
3265 When combined with options such as @option{--install}, roll back occurs
3266 before any other actions.
3268 When rolling back from the first generation that actually contains
3269 installed packages, the profile is made to point to the @dfn{zeroth
3270 generation}, which contains no files apart from its own metadata.
3272 After having rolled back, installing, removing, or upgrading packages
3273 overwrites previous future generations. Thus, the history of the
3274 generations in a profile is always linear.
3276 @item --switch-generation=@var{pattern}
3277 @itemx -S @var{pattern}
3279 Switch to a particular generation defined by @var{pattern}.
3281 @var{pattern} may be either a generation number or a number prefixed
3282 with ``+'' or ``-''. The latter means: move forward/backward by a
3283 specified number of generations. For example, if you want to return to
3284 the latest generation after @option{--roll-back}, use
3285 @option{--switch-generation=+1}.
3287 The difference between @option{--roll-back} and
3288 @option{--switch-generation=-1} is that @option{--switch-generation} will
3289 not make a zeroth generation, so if a specified generation does not
3290 exist, the current generation will not be changed.
3292 @item --search-paths[=@var{kind}]
3293 @cindex search paths
3294 Report environment variable definitions, in Bash syntax, that may be
3295 needed in order to use the set of installed packages. These environment
3296 variables are used to specify @dfn{search paths} for files used by some
3297 of the installed packages.
3299 For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
3300 environment variables to be defined so it can look for headers and
3301 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
3302 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
3303 library are installed in the profile, then @option{--search-paths} will
3304 suggest setting these variables to @file{@var{profile}/include} and
3305 @file{@var{profile}/lib}, respectively.
3307 The typical use case is to define these environment variables in the
3311 $ eval `guix package --search-paths`
3314 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
3315 meaning that the returned environment variable definitions will either
3316 be exact settings, or prefixes or suffixes of the current value of these
3317 variables. When omitted, @var{kind} defaults to @code{exact}.
3319 This option can also be used to compute the @emph{combined} search paths
3320 of several profiles. Consider this example:
3323 $ guix package -p foo -i guile
3324 $ guix package -p bar -i guile-json
3325 $ guix package -p foo -p bar --search-paths
3328 The last command above reports about the @env{GUILE_LOAD_PATH}
3329 variable, even though, taken individually, neither @file{foo} nor
3330 @file{bar} would lead to that recommendation.
3333 @item --profile=@var{profile}
3334 @itemx -p @var{profile}
3335 Use @var{profile} instead of the user's default profile.
3337 @var{profile} must be the name of a file that will be created upon
3338 completion. Concretely, @var{profile} will be a mere symbolic link
3339 (``symlink'') pointing to the actual profile where packages are
3343 $ guix install hello -p ~/code/my-profile
3345 $ ~/code/my-profile/bin/hello
3349 All it takes to get rid of the profile is to remove this symlink and its
3350 siblings that point to specific generations:
3353 $ rm ~/code/my-profile ~/code/my-profile-*-link
3356 @item --list-profiles
3357 List all the user's profiles:
3360 $ guix package --list-profiles
3361 /home/charlie/.guix-profile
3362 /home/charlie/code/my-profile
3363 /home/charlie/code/devel-profile
3364 /home/charlie/tmp/test
3367 When running as root, list all the profiles of all the users.
3369 @cindex collisions, in a profile
3370 @cindex colliding packages in profiles
3371 @cindex profile collisions
3372 @item --allow-collisions
3373 Allow colliding packages in the new profile. Use at your own risk!
3375 By default, @command{guix package} reports as an error @dfn{collisions}
3376 in the profile. Collisions happen when two or more different versions
3377 or variants of a given package end up in the profile.
3380 Use the bootstrap Guile to build the profile. This option is only
3381 useful to distribution developers.
3385 In addition to these actions, @command{guix package} supports the
3386 following options to query the current state of a profile, or the
3387 availability of packages:
3391 @item --search=@var{regexp}
3392 @itemx -s @var{regexp}
3393 @anchor{guix-search}
3394 @cindex searching for packages
3395 List the available packages whose name, synopsis, or description matches
3396 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3397 Print all the metadata of matching packages in
3398 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3399 GNU recutils manual}).
3401 This allows specific fields to be extracted using the @command{recsel}
3402 command, for instance:
3405 $ guix package -s malloc | recsel -p name,version,relevance
3419 Similarly, to show the name of all the packages available under the
3420 terms of the GNU@tie{}LGPL version 3:
3423 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3430 It is also possible to refine search results using several @code{-s} flags to
3431 @command{guix package}, or several arguments to @command{guix search}. For
3432 example, the following command returns a list of board games (this time using
3433 the @command{guix search} alias):
3436 $ guix search '\<board\>' game | recsel -p name
3441 If we were to omit @code{-s game}, we would also get software packages
3442 that deal with printed circuit boards; removing the angle brackets
3443 around @code{board} would further add packages that have to do with
3446 And now for a more elaborate example. The following command searches
3447 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3448 libraries, and prints the name and synopsis of the matching packages:
3451 $ guix search crypto library | \
3452 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3456 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3457 information on @dfn{selection expressions} for @code{recsel -e}.
3459 @item --show=@var{package}
3460 Show details about @var{package}, taken from the list of available packages, in
3461 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3465 $ guix package --show=python | recsel -p name,version
3473 You may also specify the full name of a package to only get details about a
3474 specific version of it (this time using the @command{guix show} alias):
3476 $ guix show python@@3.4 | recsel -p name,version
3483 @item --list-installed[=@var{regexp}]
3484 @itemx -I [@var{regexp}]
3485 List the currently installed packages in the specified profile, with the
3486 most recently installed packages shown last. When @var{regexp} is
3487 specified, list only installed packages whose name matches @var{regexp}.
3489 For each installed package, print the following items, separated by
3490 tabs: the package name, its version string, the part of the package that
3491 is installed (for instance, @code{out} for the default output,
3492 @code{include} for its headers, etc.), and the path of this package in
3495 @item --list-available[=@var{regexp}]
3496 @itemx -A [@var{regexp}]
3497 List packages currently available in the distribution for this system
3498 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3499 available packages whose name matches @var{regexp}.
3501 For each package, print the following items separated by tabs: its name,
3502 its version string, the parts of the package (@pxref{Packages with
3503 Multiple Outputs}), and the source location of its definition.
3505 @item --list-generations[=@var{pattern}]
3506 @itemx -l [@var{pattern}]
3508 Return a list of generations along with their creation dates; for each
3509 generation, show the installed packages, with the most recently
3510 installed packages shown last. Note that the zeroth generation is never
3513 For each installed package, print the following items, separated by
3514 tabs: the name of a package, its version string, the part of the package
3515 that is installed (@pxref{Packages with Multiple Outputs}), and the
3516 location of this package in the store.
3518 When @var{pattern} is used, the command returns only matching
3519 generations. Valid patterns include:
3522 @item @emph{Integers and comma-separated integers}. Both patterns denote
3523 generation numbers. For instance, @option{--list-generations=1} returns
3526 And @option{--list-generations=1,8,2} outputs three generations in the
3527 specified order. Neither spaces nor trailing commas are allowed.
3529 @item @emph{Ranges}. @option{--list-generations=2..9} prints the
3530 specified generations and everything in between. Note that the start of
3531 a range must be smaller than its end.
3533 It is also possible to omit the endpoint. For example,
3534 @option{--list-generations=2..}, returns all generations starting from the
3537 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3538 or months by passing an integer along with the first letter of the
3539 duration. For example, @option{--list-generations=20d} lists generations
3540 that are up to 20 days old.
3543 @item --delete-generations[=@var{pattern}]
3544 @itemx -d [@var{pattern}]
3545 When @var{pattern} is omitted, delete all generations except the current
3548 This command accepts the same patterns as @option{--list-generations}.
3549 When @var{pattern} is specified, delete the matching generations. When
3550 @var{pattern} specifies a duration, generations @emph{older} than the
3551 specified duration match. For instance, @option{--delete-generations=1m}
3552 deletes generations that are more than one month old.
3554 If the current generation matches, it is @emph{not} deleted. Also, the
3555 zeroth generation is never deleted.
3557 Note that deleting generations prevents rolling back to them.
3558 Consequently, this command must be used with care.
3562 Finally, since @command{guix package} may actually start build
3563 processes, it supports all the common build options (@pxref{Common Build
3564 Options}). It also supports package transformation options, such as
3565 @option{--with-source} (@pxref{Package Transformation Options}).
3566 However, note that package transformations are lost when upgrading; to
3567 preserve transformations across upgrades, you should define your own
3568 package variant in a Guile module and add it to @env{GUIX_PACKAGE_PATH}
3569 (@pxref{Defining Packages}).
3572 @section Substitutes
3575 @cindex pre-built binaries
3576 Guix supports transparent source/binary deployment, which means that it
3577 can either build things locally, or download pre-built items from a
3578 server, or both. We call these pre-built items @dfn{substitutes}---they
3579 are substitutes for local build results. In many cases, downloading a
3580 substitute is much faster than building things locally.
3582 Substitutes can be anything resulting from a derivation build
3583 (@pxref{Derivations}). Of course, in the common case, they are
3584 pre-built package binaries, but source tarballs, for instance, which
3585 also result from derivation builds, can be available as substitutes.
3588 * Official Substitute Server:: One particular source of substitutes.
3589 * Substitute Server Authorization:: How to enable or disable substitutes.
3590 * Getting Substitutes from Other Servers:: Substitute diversity.
3591 * Substitute Authentication:: How Guix verifies substitutes.
3592 * Proxy Settings:: How to get substitutes via proxy.
3593 * Substitution Failure:: What happens when substitution fails.
3594 * On Trusting Binaries:: How can you trust that binary blob?
3597 @node Official Substitute Server
3598 @subsection Official Substitute Server
3601 The @code{@value{SUBSTITUTE-SERVER}} server is a front-end to an official build farm
3602 that builds packages from Guix continuously for some
3603 architectures, and makes them available as substitutes. This is the
3604 default source of substitutes; it can be overridden by passing the
3605 @option{--substitute-urls} option either to @command{guix-daemon}
3606 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3607 or to client tools such as @command{guix package}
3608 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3611 Substitute URLs can be either HTTP or HTTPS.
3612 HTTPS is recommended because communications are encrypted; conversely,
3613 using HTTP makes all communications visible to an eavesdropper, who
3614 could use the information gathered to determine, for instance, whether
3615 your system has unpatched security vulnerabilities.
3617 Substitutes from the official build farm are enabled by default when
3618 using Guix System (@pxref{GNU Distribution}). However,
3619 they are disabled by default when using Guix on a foreign distribution,
3620 unless you have explicitly enabled them via one of the recommended
3621 installation steps (@pxref{Installation}). The following paragraphs
3622 describe how to enable or disable substitutes for the official build
3623 farm; the same procedure can also be used to enable substitutes for any
3624 other substitute server.
3626 @node Substitute Server Authorization
3627 @subsection Substitute Server Authorization
3630 @cindex substitutes, authorization thereof
3631 @cindex access control list (ACL), for substitutes
3632 @cindex ACL (access control list), for substitutes
3633 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER}} or a
3635 must add its public key to the access control list (ACL) of archive
3636 imports, using the @command{guix archive} command (@pxref{Invoking guix
3637 archive}). Doing so implies that you trust @code{@value{SUBSTITUTE-SERVER}} to not
3638 be compromised and to serve genuine substitutes.
3641 If you are using Guix System, you can skip this section: Guix System
3642 authorizes substitutes from @code{@value{SUBSTITUTE-SERVER}} by default.
3645 The public key for @code{@value{SUBSTITUTE-SERVER}} is installed along with Guix, in
3646 @code{@var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub}, where @var{prefix} is
3647 the installation prefix of Guix. If you installed Guix from source,
3648 make sure you checked the GPG signature of
3649 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3650 Then, you can run something like this:
3653 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER}.pub
3656 Once this is in place, the output of a command like @code{guix build}
3657 should change from something like:
3660 $ guix build emacs --dry-run
3661 The following derivations would be built:
3662 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3663 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3664 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3665 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
3673 $ guix build emacs --dry-run
3674 112.3 MB would be downloaded:
3675 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
3676 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
3677 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
3678 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
3683 The text changed from ``The following derivations would be built'' to
3684 ``112.3 MB would be downloaded''. This indicates that substitutes from
3685 @code{@value{SUBSTITUTE-SERVER}} are usable and will be downloaded, when
3686 possible, for future builds.
3688 @cindex substitutes, how to disable
3689 The substitute mechanism can be disabled globally by running
3690 @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
3691 guix-daemon}). It can also be disabled temporarily by passing the
3692 @option{--no-substitutes} option to @command{guix package},
3693 @command{guix build}, and other command-line tools.
3695 @node Getting Substitutes from Other Servers
3696 @subsection Getting Substitutes from Other Servers
3698 @cindex substitute servers, adding more
3699 Guix can look up and fetch substitutes from several servers. This is
3700 useful when you are using packages from additional channels for which
3701 the official server does not have substitutes but another server
3702 provides them. Another situation where this is useful is when you would
3703 prefer to download from your organization's substitute server, resorting
3704 to the official server only as a fallback or dismissing it altogether.
3706 You can give Guix a list of substitute server URLs and it will check
3707 them in the specified order. You also need to explicitly authorize the
3708 public keys of substitute servers to instruct Guix to accept the
3709 substitutes they sign.
3711 On Guix System, this is achieved by modifying the configuration of the
3712 @code{guix} service. Since the @code{guix} service is part of the
3713 default lists of services, @code{%base-services} and
3714 @code{%desktop-services}, you can use @code{modify-services} to change
3715 its configuration and add the URLs and substitute keys that you want
3716 (@pxref{Service Reference, @code{modify-services}}).
3718 As an example, suppose you want to fetch substitutes from
3719 @code{guix.example.org} and to authorize the signing key of that server,
3720 in addition to the default @code{@value{SUBSTITUTE-SERVER}}. The
3721 resulting operating system configuration will look something like:
3727 ;; Assume we're starting from '%desktop-services'. Replace it
3728 ;; with the list of services you're actually using.
3729 (modify-services %desktop-services
3730 (guix-service-type config =>
3734 (append (list "https://guix.example.org")
3735 %default-substitute-urls))
3737 (append (list (local-file "./key.pub"))
3738 %default-authorized-guix-keys)))))))
3741 This assumes that the file @file{key.pub} contains the signing key of
3742 @code{guix.example.org}. With this change in place in your operating
3743 system configuration file (say @file{/etc/config.scm}), you can
3744 reconfigure and restart the @code{guix-daemon} service or reboot so the
3745 changes take effect:
3748 $ sudo guix system reconfigure /etc/config.scm
3749 $ sudo herd restart guix-daemon
3752 If you're running Guix on a ``foreign distro'', you would instead take
3753 the following steps to get substitutes from additional servers:
3757 Edit the service configuration file for @code{guix-daemon}; when using
3758 systemd, this is normally
3759 @file{/etc/systemd/system/guix-daemon.service}. Add the
3760 @option{--substitute-urls} option on the @command{guix-daemon} command
3761 line and list the URLs of interest (@pxref{daemon-substitute-urls,
3762 @code{guix-daemon --substitute-urls}}):
3765 @dots{} --substitute-urls='https://guix.example.org https://@value{SUBSTITUTE-SERVER}'
3769 Restart the daemon. For systemd, it goes like this:
3772 systemctl daemon-reload
3773 systemctl restart guix-daemon.service
3777 Authorize the key of the new server (@pxref{Invoking guix archive}):
3780 guix archive --authorize < key.pub
3783 Again this assumes @file{key.pub} contains the public key that
3784 @code{guix.example.org} uses to sign substitutes.
3787 Now you're all set! Substitutes will be preferably taken from
3788 @code{https://guix.example.org}, using @code{@value{SUBSTITUTE-SERVER}}
3789 as a fallback. Of course you can list as many substitute servers as you
3790 like, with the caveat that substitute lookup can be slowed down if too
3791 many servers need to be contacted.
3793 Note that there are also situations where one may want to add the URL of
3794 a substitute server @emph{without} authorizing its key.
3795 @xref{Substitute Authentication}, to understand this fine point.
3797 @node Substitute Authentication
3798 @subsection Substitute Authentication
3800 @cindex digital signatures
3801 Guix detects and raises an error when attempting to use a substitute
3802 that has been tampered with. Likewise, it ignores substitutes that are
3803 not signed, or that are not signed by one of the keys listed in the ACL.
3805 There is one exception though: if an unauthorized server provides
3806 substitutes that are @emph{bit-for-bit identical} to those provided by
3807 an authorized server, then the unauthorized server becomes eligible for
3808 downloads. For example, assume we have chosen two substitute servers
3812 --substitute-urls="https://a.example.org https://b.example.org"
3816 @cindex reproducible builds
3817 If the ACL contains only the key for @samp{b.example.org}, and if
3818 @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
3819 then Guix will download substitutes from @samp{a.example.org} because it
3820 comes first in the list and can be considered a mirror of
3821 @samp{b.example.org}. In practice, independent build machines usually
3822 produce the same binaries, thanks to bit-reproducible builds (see
3825 When using HTTPS, the server's X.509 certificate is @emph{not} validated
3826 (in other words, the server is not authenticated), contrary to what
3827 HTTPS clients such as Web browsers usually do. This is because Guix
3828 authenticates substitute information itself, as explained above, which
3829 is what we care about (whereas X.509 certificates are about
3830 authenticating bindings between domain names and public keys).
3832 @node Proxy Settings
3833 @subsection Proxy Settings
3837 Substitutes are downloaded over HTTP or HTTPS. The @env{http_proxy} and
3838 @env{https_proxy} environment variables can be set in the environment of
3839 @command{guix-daemon} and are honored for downloads of substitutes.
3840 Note that the value of those environment variables in the environment
3841 where @command{guix build}, @command{guix package}, and other client
3842 commands are run has @emph{absolutely no effect}.
3844 @node Substitution Failure
3845 @subsection Substitution Failure
3847 Even when a substitute for a derivation is available, sometimes the
3848 substitution attempt will fail. This can happen for a variety of
3849 reasons: the substitute server might be offline, the substitute may
3850 recently have been deleted, the connection might have been interrupted,
3853 When substitutes are enabled and a substitute for a derivation is
3854 available, but the substitution attempt fails, Guix will attempt to
3855 build the derivation locally depending on whether or not
3856 @option{--fallback} was given (@pxref{fallback-option,, common build
3857 option @option{--fallback}}). Specifically, if @option{--fallback} was
3858 omitted, then no local build will be performed, and the derivation is
3859 considered to have failed. However, if @option{--fallback} was given,
3860 then Guix will attempt to build the derivation locally, and the success
3861 or failure of the derivation depends on the success or failure of the
3862 local build. Note that when substitutes are disabled or no substitute
3863 is available for the derivation in question, a local build will
3864 @emph{always} be performed, regardless of whether or not
3865 @option{--fallback} was given.
3867 To get an idea of how many substitutes are available right now, you can
3868 try running the @command{guix weather} command (@pxref{Invoking guix
3869 weather}). This command provides statistics on the substitutes provided
3872 @node On Trusting Binaries
3873 @subsection On Trusting Binaries
3875 @cindex trust, of pre-built binaries
3876 Today, each individual's control over their own computing is at the
3877 mercy of institutions, corporations, and groups with enough power and
3878 determination to subvert the computing infrastructure and exploit its
3879 weaknesses. While using @code{@value{SUBSTITUTE-SERVER}} substitutes can be
3880 convenient, we encourage users to also build on their own, or even run
3881 their own build farm, such that @code{@value{SUBSTITUTE-SERVER}} is less of an
3882 interesting target. One way to help is by publishing the software you
3883 build using @command{guix publish} so that others have one more choice
3884 of server to download substitutes from (@pxref{Invoking guix publish}).
3886 Guix has the foundations to maximize build reproducibility
3887 (@pxref{Features}). In most cases, independent builds of a given
3888 package or derivation should yield bit-identical results. Thus, through
3889 a diverse set of independent package builds, we can strengthen the
3890 integrity of our systems. The @command{guix challenge} command aims to
3891 help users assess substitute servers, and to assist developers in
3892 finding out about non-deterministic package builds (@pxref{Invoking guix
3893 challenge}). Similarly, the @option{--check} option of @command{guix
3894 build} allows users to check whether previously-installed substitutes
3895 are genuine by rebuilding them locally (@pxref{build-check,
3896 @command{guix build --check}}).
3898 In the future, we want Guix to have support to publish and retrieve
3899 binaries to/from other users, in a peer-to-peer fashion. If you would
3900 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
3902 @node Packages with Multiple Outputs
3903 @section Packages with Multiple Outputs
3905 @cindex multiple-output packages
3906 @cindex package outputs
3909 Often, packages defined in Guix have a single @dfn{output}---i.e., the
3910 source package leads to exactly one directory in the store. When running
3911 @command{guix install glibc}, one installs the default output of the
3912 GNU libc package; the default output is called @code{out}, but its name
3913 can be omitted as shown in this command. In this particular case, the
3914 default output of @code{glibc} contains all the C header files, shared
3915 libraries, static libraries, Info documentation, and other supporting
3918 Sometimes it is more appropriate to separate the various types of files
3919 produced from a single source package into separate outputs. For
3920 instance, the GLib C library (used by GTK+ and related packages)
3921 installs more than 20 MiB of reference documentation as HTML pages.
3922 To save space for users who do not need it, the documentation goes to a
3923 separate output, called @code{doc}. To install the main GLib output,
3924 which contains everything but the documentation, one would run:
3930 @cindex documentation
3931 The command to install its documentation is:
3934 guix install glib:doc
3937 Some packages install programs with different ``dependency footprints''.
3938 For instance, the WordNet package installs both command-line tools and
3939 graphical user interfaces (GUIs). The former depend solely on the C
3940 library, whereas the latter depend on Tcl/Tk and the underlying X
3941 libraries. In this case, we leave the command-line tools in the default
3942 output, whereas the GUIs are in a separate output. This allows users
3943 who do not need the GUIs to save space. The @command{guix size} command
3944 can help find out about such situations (@pxref{Invoking guix size}).
3945 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
3947 There are several such multiple-output packages in the GNU distribution.
3948 Other conventional output names include @code{lib} for libraries and
3949 possibly header files, @code{bin} for stand-alone programs, and
3950 @code{debug} for debugging information (@pxref{Installing Debugging
3951 Files}). The outputs of a packages are listed in the third column of
3952 the output of @command{guix package --list-available} (@pxref{Invoking
3956 @node Invoking guix gc
3957 @section Invoking @command{guix gc}
3959 @cindex garbage collector
3961 Packages that are installed, but not used, may be @dfn{garbage-collected}.
3962 The @command{guix gc} command allows users to explicitly run the garbage
3963 collector to reclaim space from the @file{/gnu/store} directory. It is
3964 the @emph{only} way to remove files from @file{/gnu/store}---removing
3965 files or directories manually may break it beyond repair!
3968 @cindex garbage collector roots
3969 The garbage collector has a set of known @dfn{roots}: any file under
3970 @file{/gnu/store} reachable from a root is considered @dfn{live} and
3971 cannot be deleted; any other file is considered @dfn{dead} and may be
3972 deleted. The set of garbage collector roots (``GC roots'' for short)
3973 includes default user profiles; by default, the symlinks under
3974 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
3975 added with @command{guix build --root}, for example (@pxref{Invoking
3976 guix build}). The @command{guix gc --list-roots} command lists them.
3978 Prior to running @code{guix gc --collect-garbage} to make space, it is
3979 often useful to remove old generations from user profiles; that way, old
3980 package builds referenced by those generations can be reclaimed. This
3981 is achieved by running @code{guix package --delete-generations}
3982 (@pxref{Invoking guix package}).
3984 Our recommendation is to run a garbage collection periodically, or when
3985 you are short on disk space. For instance, to guarantee that at least
3986 5@tie{}GB are available on your disk, simply run:
3992 It is perfectly safe to run as a non-interactive periodic job
3993 (@pxref{Scheduled Job Execution}, for how to set up such a job).
3994 Running @command{guix gc} with no arguments will collect as
3995 much garbage as it can, but that is often inconvenient: you may find
3996 yourself having to rebuild or re-download software that is ``dead'' from
3997 the GC viewpoint but that is necessary to build other pieces of
3998 software---e.g., the compiler tool chain.
4000 The @command{guix gc} command has three modes of operation: it can be
4001 used to garbage-collect any dead files (the default), to delete specific
4002 files (the @option{--delete} option), to print garbage-collector
4003 information, or for more advanced queries. The garbage collection
4004 options are as follows:
4007 @item --collect-garbage[=@var{min}]
4008 @itemx -C [@var{min}]
4009 Collect garbage---i.e., unreachable @file{/gnu/store} files and
4010 sub-directories. This is the default operation when no option is
4013 When @var{min} is given, stop once @var{min} bytes have been collected.
4014 @var{min} may be a number of bytes, or it may include a unit as a
4015 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
4016 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
4018 When @var{min} is omitted, collect all the garbage.
4020 @item --free-space=@var{free}
4021 @itemx -F @var{free}
4022 Collect garbage until @var{free} space is available under
4023 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
4024 as @code{500MiB}, as described above.
4026 When @var{free} or more is already available in @file{/gnu/store}, do
4027 nothing and exit immediately.
4029 @item --delete-generations[=@var{duration}]
4030 @itemx -d [@var{duration}]
4031 Before starting the garbage collection process, delete all the generations
4032 older than @var{duration}, for all the user profiles; when run as root, this
4033 applies to all the profiles @emph{of all the users}.
4035 For example, this command deletes all the generations of all your profiles
4036 that are older than 2 months (except generations that are current), and then
4037 proceeds to free space until at least 10 GiB are available:
4040 guix gc -d 2m -F 10G
4045 Attempt to delete all the store files and directories specified as
4046 arguments. This fails if some of the files are not in the store, or if
4047 they are still live.
4049 @item --list-failures
4050 List store items corresponding to cached build failures.
4052 This prints nothing unless the daemon was started with
4053 @option{--cache-failures} (@pxref{Invoking guix-daemon,
4054 @option{--cache-failures}}).
4057 List the GC roots owned by the user; when run as root, list @emph{all} the GC
4061 List store items in use by currently running processes. These store
4062 items are effectively considered GC roots: they cannot be deleted.
4064 @item --clear-failures
4065 Remove the specified store items from the failed-build cache.
4067 Again, this option only makes sense when the daemon is started with
4068 @option{--cache-failures}. Otherwise, it does nothing.
4071 Show the list of dead files and directories still present in the
4072 store---i.e., files and directories no longer reachable from any root.
4075 Show the list of live store files and directories.
4079 In addition, the references among existing store files can be queried:
4085 @cindex package dependencies
4086 List the references (respectively, the referrers) of store files given
4092 List the requisites of the store files passed as arguments. Requisites
4093 include the store files themselves, their references, and the references
4094 of these, recursively. In other words, the returned list is the
4095 @dfn{transitive closure} of the store files.
4097 @xref{Invoking guix size}, for a tool to profile the size of the closure
4098 of an element. @xref{Invoking guix graph}, for a tool to visualize
4099 the graph of references.
4103 Return the derivation(s) leading to the given store items
4104 (@pxref{Derivations}).
4106 For example, this command:
4109 guix gc --derivers `guix package -I ^emacs$ | cut -f4`
4113 returns the @file{.drv} file(s) leading to the @code{emacs} package
4114 installed in your profile.
4116 Note that there may be zero matching @file{.drv} files, for instance
4117 because these files have been garbage-collected. There can also be more
4118 than one matching @file{.drv} due to fixed-output derivations.
4121 Lastly, the following options allow you to check the integrity of the
4122 store and to control disk usage.
4126 @item --verify[=@var{options}]
4127 @cindex integrity, of the store
4128 @cindex integrity checking
4129 Verify the integrity of the store.
4131 By default, make sure that all the store items marked as valid in the
4132 database of the daemon actually exist in @file{/gnu/store}.
4134 When provided, @var{options} must be a comma-separated list containing one
4135 or more of @code{contents} and @code{repair}.
4137 When passing @option{--verify=contents}, the daemon computes the
4138 content hash of each store item and compares it against its hash in the
4139 database. Hash mismatches are reported as data corruptions. Because it
4140 traverses @emph{all the files in the store}, this command can take a
4141 long time, especially on systems with a slow disk drive.
4143 @cindex repairing the store
4144 @cindex corruption, recovering from
4145 Using @option{--verify=repair} or @option{--verify=contents,repair}
4146 causes the daemon to try to repair corrupt store items by fetching
4147 substitutes for them (@pxref{Substitutes}). Because repairing is not
4148 atomic, and thus potentially dangerous, it is available only to the
4149 system administrator. A lightweight alternative, when you know exactly
4150 which items in the store are corrupt, is @command{guix build --repair}
4151 (@pxref{Invoking guix build}).
4154 @cindex deduplication
4155 Optimize the store by hard-linking identical files---this is
4156 @dfn{deduplication}.
4158 The daemon performs deduplication after each successful build or archive
4159 import, unless it was started with @option{--disable-deduplication}
4160 (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
4161 this option is primarily useful when the daemon was running with
4162 @option{--disable-deduplication}.
4166 @node Invoking guix pull
4167 @section Invoking @command{guix pull}
4169 @cindex upgrading Guix
4170 @cindex updating Guix
4171 @cindex @command{guix pull}
4173 @cindex security, @command{guix pull}
4174 @cindex authenticity, of code obtained with @command{guix pull}
4175 Packages are installed or upgraded to the latest version available in
4176 the distribution currently available on your local machine. To update
4177 that distribution, along with the Guix tools, you must run @command{guix
4178 pull}: the command downloads the latest Guix source code and package
4179 descriptions, and deploys it. Source code is downloaded from a
4180 @uref{https://git-scm.com, Git} repository, by default the official
4181 GNU@tie{}Guix repository, though this can be customized. @command{guix
4182 pull} ensures that the code it downloads is @emph{authentic} by
4183 verifying that commits are signed by Guix developers.
4185 Specifically, @command{guix pull} downloads code from the @dfn{channels}
4186 (@pxref{Channels}) specified by one of the followings, in this order:
4190 the @option{--channels} option;
4192 the user's @file{~/.config/guix/channels.scm} file;
4194 the system-wide @file{/etc/guix/channels.scm} file;
4196 the built-in default channels specified in the @code{%default-channels}
4200 On completion, @command{guix package} will use packages and package
4201 versions from this just-retrieved copy of Guix. Not only that, but all
4202 the Guix commands and Scheme modules will also be taken from that latest
4203 version. New @command{guix} sub-commands added by the update also
4206 Any user can update their Guix copy using @command{guix pull}, and the
4207 effect is limited to the user who ran @command{guix pull}. For
4208 instance, when user @code{root} runs @command{guix pull}, this has no
4209 effect on the version of Guix that user @code{alice} sees, and vice
4212 The result of running @command{guix pull} is a @dfn{profile} available
4213 under @file{~/.config/guix/current} containing the latest Guix. Thus,
4214 make sure to add it to the beginning of your search path so that you use
4215 the latest version, and similarly for the Info manual
4216 (@pxref{Documentation}):
4219 export PATH="$HOME/.config/guix/current/bin:$PATH"
4220 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
4223 The @option{--list-generations} or @option{-l} option lists past generations
4224 produced by @command{guix pull}, along with details about their provenance:
4228 Generation 1 Jun 10 2018 00:18:18
4230 repository URL: https://git.savannah.gnu.org/git/guix.git
4231 branch: origin/master
4232 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
4234 Generation 2 Jun 11 2018 11:02:49
4236 repository URL: https://git.savannah.gnu.org/git/guix.git
4237 branch: origin/master
4238 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
4239 2 new packages: keepalived, libnfnetlink
4240 6 packages upgraded: emacs-nix-mode@@2.0.4,
4241 guile2.0-guix@@0.14.0-12.77a1aac, guix@@0.14.0-12.77a1aac,
4242 heimdal@@7.5.0, milkytracker@@1.02.00, nix@@2.0.4
4244 Generation 3 Jun 13 2018 23:31:07 (current)
4246 repository URL: https://git.savannah.gnu.org/git/guix.git
4247 branch: origin/master
4248 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
4249 28 new packages: emacs-helm-ls-git, emacs-helm-mu, @dots{}
4250 69 packages upgraded: borg@@1.1.6, cheese@@3.28.0, @dots{}
4253 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
4254 describe the current status of Guix.
4256 This @code{~/.config/guix/current} profile works exactly like the profiles
4257 created by @command{guix package} (@pxref{Invoking guix package}). That
4258 is, you can list generations, roll back to the previous
4259 generation---i.e., the previous Guix---and so on:
4262 $ guix pull --roll-back
4263 switched from generation 3 to 2
4264 $ guix pull --delete-generations=1
4265 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4268 You can also use @command{guix package} (@pxref{Invoking guix package})
4269 to manage the profile by naming it explicitly:
4271 $ guix package -p ~/.config/guix/current --roll-back
4272 switched from generation 3 to 2
4273 $ guix package -p ~/.config/guix/current --delete-generations=1
4274 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4277 The @command{guix pull} command is usually invoked with no arguments,
4278 but it supports the following options:
4281 @item --url=@var{url}
4282 @itemx --commit=@var{commit}
4283 @itemx --branch=@var{branch}
4284 Download code for the @code{guix} channel from the specified @var{url}, at the
4285 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4286 string), or @var{branch}.
4288 @cindex @file{channels.scm}, configuration file
4289 @cindex configuration file for channels
4290 These options are provided for convenience, but you can also specify your
4291 configuration in the @file{~/.config/guix/channels.scm} file or using the
4292 @option{--channels} option (see below).
4294 @item --channels=@var{file}
4295 @itemx -C @var{file}
4296 Read the list of channels from @var{file} instead of
4297 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
4298 @var{file} must contain Scheme code that
4299 evaluates to a list of channel objects. @xref{Channels}, for more
4302 @cindex channel news
4305 Display the list of packages added or upgraded since the previous
4306 generation, as well as, occasionally, news written by channel authors
4307 for their users (@pxref{Channels, Writing Channel News}).
4309 The package information is the same as displayed upon @command{guix
4310 pull} completion, but without ellipses; it is also similar to the output
4311 of @command{guix pull -l} for the last generation (see below).
4313 @item --list-generations[=@var{pattern}]
4314 @itemx -l [@var{pattern}]
4315 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
4316 is provided, the subset of generations that match @var{pattern}.
4317 The syntax of @var{pattern} is the same as with @code{guix package
4318 --list-generations} (@pxref{Invoking guix package}).
4321 @cindex rolling back
4322 @cindex undoing transactions
4323 @cindex transactions, undoing
4324 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
4325 undo the last transaction.
4327 @item --switch-generation=@var{pattern}
4328 @itemx -S @var{pattern}
4330 Switch to a particular generation defined by @var{pattern}.
4332 @var{pattern} may be either a generation number or a number prefixed
4333 with ``+'' or ``-''. The latter means: move forward/backward by a
4334 specified number of generations. For example, if you want to return to
4335 the latest generation after @option{--roll-back}, use
4336 @option{--switch-generation=+1}.
4338 @item --delete-generations[=@var{pattern}]
4339 @itemx -d [@var{pattern}]
4340 When @var{pattern} is omitted, delete all generations except the current
4343 This command accepts the same patterns as @option{--list-generations}.
4344 When @var{pattern} is specified, delete the matching generations. When
4345 @var{pattern} specifies a duration, generations @emph{older} than the
4346 specified duration match. For instance, @option{--delete-generations=1m}
4347 deletes generations that are more than one month old.
4349 If the current generation matches, it is @emph{not} deleted.
4351 Note that deleting generations prevents rolling back to them.
4352 Consequently, this command must be used with care.
4354 @xref{Invoking guix describe}, for a way to display information about the
4355 current generation only.
4357 @item --profile=@var{profile}
4358 @itemx -p @var{profile}
4359 Use @var{profile} instead of @file{~/.config/guix/current}.
4363 Show which channel commit(s) would be used and what would be built or
4364 substituted but do not actually do it.
4366 @item --allow-downgrades
4367 Allow pulling older or unrelated revisions of channels than those
4370 @cindex downgrade attacks, protection against
4371 By default, @command{guix pull} protects against so-called ``downgrade
4372 attacks'' whereby the Git repository of a channel would be reset to an
4373 earlier or unrelated revision of itself, potentially leading you to
4374 install older, known-vulnerable versions of software packages.
4377 Make sure you understand its security implications before using
4378 @option{--allow-downgrades}.
4381 @item --disable-authentication
4382 Allow pulling channel code without authenticating it.
4384 @cindex authentication, of channel code
4385 By default, @command{guix pull} authenticates code downloaded from
4386 channels by verifying that its commits are signed by authorized
4387 developers, and raises an error if this is not the case. This option
4388 instructs it to not perform any such verification.
4391 Make sure you understand its security implications before using
4392 @option{--disable-authentication}.
4395 @item --system=@var{system}
4396 @itemx -s @var{system}
4397 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4398 the system type of the build host.
4401 Use the bootstrap Guile to build the latest Guix. This option is only
4402 useful to Guix developers.
4405 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
4406 repository and branch to pull from, as well as @emph{additional} repositories
4407 containing package modules that should be deployed. @xref{Channels}, for more
4410 In addition, @command{guix pull} supports all the common build options
4411 (@pxref{Common Build Options}).
4413 @node Invoking guix time-machine
4414 @section Invoking @command{guix time-machine}
4416 @cindex @command{guix time-machine}
4417 @cindex pinning, channels
4418 @cindex replicating Guix
4419 @cindex reproducibility, of Guix
4421 The @command{guix time-machine} command provides access to other
4422 revisions of Guix, for example to install older versions of packages,
4423 or to reproduce a computation in an identical environment. The revision
4424 of Guix to be used is defined by a commit or by a channel
4425 description file created by @command{guix describe}
4426 (@pxref{Invoking guix describe}).
4428 The general syntax is:
4431 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4434 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4435 @command{guix} command of the specified revision. The @var{options} that define
4436 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4439 @item --url=@var{url}
4440 @itemx --commit=@var{commit}
4441 @itemx --branch=@var{branch}
4442 Use the @code{guix} channel from the specified @var{url}, at the
4443 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4444 string), or @var{branch}.
4446 @item --channels=@var{file}
4447 @itemx -C @var{file}
4448 Read the list of channels from @var{file}. @var{file} must contain
4449 Scheme code that evaluates to a list of channel objects.
4450 @xref{Channels} for more information.
4453 As for @command{guix pull}, the absence of any options means that the
4454 latest commit on the master branch will be used. The command
4457 guix time-machine -- build hello
4460 will thus build the package @code{hello} as defined in the master branch,
4461 which is in general a newer revision of Guix than you have installed.
4462 Time travel works in both directions!
4464 Note that @command{guix time-machine} can trigger builds of channels and
4465 their dependencies, and these are controlled by the standard build
4466 options (@pxref{Common Build Options}).
4471 @c TODO: Remove this once we're more confident about API stability.
4473 The functionality described here is a ``technology preview'' as of version
4474 @value{VERSION}. As such, the interface is subject to change.
4478 @cindex composition of Guix revisions
4479 Sometimes you might need to mix packages from the revision of Guix you're
4480 currently running with packages available in a different revision of Guix.
4481 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4482 revisions in arbitrary ways.
4484 @cindex inferior packages
4485 Technically, an ``inferior'' is essentially a separate Guix process connected
4486 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4487 @code{(guix inferior)} module allows you to create inferiors and to
4488 communicate with them. It also provides a high-level interface to browse and
4489 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4491 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4492 to interact with a separate revision of Guix. For example, let's assume you
4493 want to install in your profile the current @code{guile} package, along with
4494 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4495 because the newer @code{guile-json} has an incompatible API and you want to
4496 run your code against the old API@. To do that, you could write a manifest for
4497 use by @code{guix package --manifest} (@pxref{Invoking guix package}); in that
4498 manifest, you would create an inferior for that old Guix revision you care
4499 about, and you would look up the @code{guile-json} package in the inferior:
4502 (use-modules (guix inferior) (guix channels)
4503 (srfi srfi-1)) ;for 'first'
4506 ;; This is the old revision from which we want to
4507 ;; extract guile-json.
4510 (url "https://git.savannah.gnu.org/git/guix.git")
4512 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4515 ;; An inferior representing the above revision.
4516 (inferior-for-channels channels))
4518 ;; Now create a manifest with the current "guile" package
4519 ;; and the old "guile-json" package.
4521 (list (first (lookup-inferior-packages inferior "guile-json"))
4522 (specification->package "guile")))
4525 On its first run, @command{guix package --manifest} might have to build the
4526 channel you specified before it can create the inferior; subsequent runs will
4527 be much faster because the Guix revision will be cached.
4529 The @code{(guix inferior)} module provides the following procedures to open an
4532 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4533 [#:cache-directory] [#:ttl]
4534 Return an inferior for @var{channels}, a list of channels. Use the cache at
4535 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4536 This procedure opens a new connection to the build daemon.
4538 As a side effect, this procedure may build or substitute binaries for
4539 @var{channels}, which can take time.
4542 @deffn {Scheme Procedure} open-inferior @var{directory} @
4543 [#:command "bin/guix"]
4544 Open the inferior Guix in @var{directory}, running
4545 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4546 the inferior could not be launched.
4549 @cindex inferior packages
4550 The procedures listed below allow you to obtain and manipulate inferior
4553 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4554 Return the list of packages known to @var{inferior}.
4557 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4559 Return the sorted list of inferior packages matching @var{name} in
4560 @var{inferior}, with highest version numbers first. If @var{version} is true,
4561 return only packages with a version number prefixed by @var{version}.
4564 @deffn {Scheme Procedure} inferior-package? @var{obj}
4565 Return true if @var{obj} is an inferior package.
4568 @deffn {Scheme Procedure} inferior-package-name @var{package}
4569 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4570 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4571 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4572 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4573 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4574 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4575 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4576 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4577 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4578 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4579 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4580 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4581 These procedures are the counterpart of package record accessors
4582 (@pxref{package Reference}). Most of them work by querying the inferior
4583 @var{package} comes from, so the inferior must still be live when you call
4587 Inferior packages can be used transparently like any other package or
4588 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4589 transparently handled by the @code{packages->manifest} procedure, which is
4590 commonly use in manifests (@pxref{Invoking guix package, the
4591 @option{--manifest} option of @command{guix package}}). Thus you can insert
4592 an inferior package pretty much anywhere you would insert a regular package:
4593 in manifests, in the @code{packages} field of your @code{operating-system}
4594 declaration, and so on.
4596 @node Invoking guix describe
4597 @section Invoking @command{guix describe}
4599 @cindex reproducibility
4600 @cindex replicating Guix
4601 Often you may want to answer questions like: ``Which revision of Guix am I
4602 using?'' or ``Which channels am I using?'' This is useful information in many
4603 situations: if you want to @emph{replicate} an environment on a different
4604 machine or user account, if you want to report a bug or to determine what
4605 change in the channels you are using caused it, or if you want to record your
4606 system state for reproducibility purposes. The @command{guix describe}
4607 command answers these questions.
4609 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4610 displays the channel(s) that it was built from, including their repository URL
4611 and commit IDs (@pxref{Channels}):
4615 Generation 10 Sep 03 2018 17:32:44 (current)
4617 repository URL: https://git.savannah.gnu.org/git/guix.git
4619 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4622 If you're familiar with the Git version control system, this is similar in
4623 spirit to @command{git describe}; the output is also similar to that of
4624 @command{guix pull --list-generations}, but limited to the current generation
4625 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4626 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4627 information is all it takes to describe the revision of Guix you're using, and
4628 also to replicate it.
4630 To make it easier to replicate Guix, @command{guix describe} can also be asked
4631 to return a list of channels instead of the human-readable description above:
4634 $ guix describe -f channels
4637 (url "https://git.savannah.gnu.org/git/guix.git")
4639 "e0fa68c7718fffd33d81af415279d6ddb518f727")
4641 (make-channel-introduction
4642 "9edb3f66fd807b096b48283debdcddccfea34bad"
4643 (openpgp-fingerprint
4644 "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
4648 You can save this to a file and feed it to @command{guix pull -C} on some
4649 other machine or at a later point in time, which will instantiate @emph{this
4650 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4651 From there on, since you're able to deploy the same revision of Guix, you can
4652 just as well @emph{replicate a complete software environment}. We humbly
4653 think that this is @emph{awesome}, and we hope you'll like it too!
4655 The details of the options supported by @command{guix describe} are as
4659 @item --format=@var{format}
4660 @itemx -f @var{format}
4661 Produce output in the specified @var{format}, one of:
4665 produce human-readable output;
4667 produce a list of channel specifications that can be passed to @command{guix
4668 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
4670 @item channels-sans-intro
4671 like @code{channels}, but omit the @code{introduction} field; use it to
4672 produce a channel specification suitable for Guix version 1.1.0 or
4673 earlier---the @code{introduction} field has to do with channel
4674 authentication (@pxref{Channels, Channel Authentication}) and is not
4675 supported by these older versions;
4678 produce a list of channel specifications in JSON format;
4680 produce a list of channel specifications in Recutils format.
4683 @item --list-formats
4684 Display available formats for @option{--format} option.
4686 @item --profile=@var{profile}
4687 @itemx -p @var{profile}
4688 Display information about @var{profile}.
4691 @node Invoking guix archive
4692 @section Invoking @command{guix archive}
4694 @cindex @command{guix archive}
4696 The @command{guix archive} command allows users to @dfn{export} files
4697 from the store into a single archive, and to later @dfn{import} them on
4698 a machine that runs Guix.
4699 In particular, it allows store files to be transferred from one machine
4700 to the store on another machine.
4703 If you're looking for a way to produce archives in a format suitable for
4704 tools other than Guix, @pxref{Invoking guix pack}.
4707 @cindex exporting store items
4708 To export store files as an archive to standard output, run:
4711 guix archive --export @var{options} @var{specifications}...
4714 @var{specifications} may be either store file names or package
4715 specifications, as for @command{guix package} (@pxref{Invoking guix
4716 package}). For instance, the following command creates an archive
4717 containing the @code{gui} output of the @code{git} package and the main
4718 output of @code{emacs}:
4721 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
4724 If the specified packages are not built yet, @command{guix archive}
4725 automatically builds them. The build process may be controlled with the
4726 common build options (@pxref{Common Build Options}).
4728 To transfer the @code{emacs} package to a machine connected over SSH,
4732 guix archive --export -r emacs | ssh the-machine guix archive --import
4736 Similarly, a complete user profile may be transferred from one machine
4737 to another like this:
4740 guix archive --export -r $(readlink -f ~/.guix-profile) | \
4741 ssh the-machine guix archive --import
4745 However, note that, in both examples, all of @code{emacs} and the
4746 profile as well as all of their dependencies are transferred (due to
4747 @option{-r}), regardless of what is already available in the store on
4748 the target machine. The @option{--missing} option can help figure out
4749 which items are missing from the target store. The @command{guix copy}
4750 command simplifies and optimizes this whole process, so this is probably
4751 what you should use in this case (@pxref{Invoking guix copy}).
4753 @cindex nar, archive format
4754 @cindex normalized archive (nar)
4755 @cindex nar bundle, archive format
4756 Each store item is written in the @dfn{normalized archive} or @dfn{nar}
4757 format (described below), and the output of @command{guix archive
4758 --export} (and input of @command{guix archive --import}) is a @dfn{nar
4762 comparable in spirit to `tar', but with differences
4763 that make it more appropriate for our purposes. First, rather than
4764 recording all Unix metadata for each file, the nar format only mentions
4765 the file type (regular, directory, or symbolic link); Unix permissions
4766 and owner/group are dismissed. Second, the order in which directory
4767 entries are stored always follows the order of file names according to
4768 the C locale collation order. This makes archive production fully
4771 That nar bundle format is essentially the concatenation of zero or more
4772 nars along with metadata for each store item it contains: its file name,
4773 references, corresponding derivation, and a digital signature.
4775 When exporting, the daemon digitally signs the contents of the archive,
4776 and that digital signature is appended. When importing, the daemon
4777 verifies the signature and rejects the import in case of an invalid
4778 signature or if the signing key is not authorized.
4779 @c FIXME: Add xref to daemon doc about signatures.
4781 The main options are:
4785 Export the specified store files or packages (see below). Write the
4786 resulting archive to the standard output.
4788 Dependencies are @emph{not} included in the output, unless
4789 @option{--recursive} is passed.
4793 When combined with @option{--export}, this instructs @command{guix archive}
4794 to include dependencies of the given items in the archive. Thus, the
4795 resulting archive is self-contained: it contains the closure of the
4796 exported store items.
4799 Read an archive from the standard input, and import the files listed
4800 therein into the store. Abort if the archive has an invalid digital
4801 signature, or if it is signed by a public key not among the authorized
4802 keys (see @option{--authorize} below).
4805 Read a list of store file names from the standard input, one per line,
4806 and write on the standard output the subset of these files missing from
4809 @item --generate-key[=@var{parameters}]
4810 @cindex signing, archives
4811 Generate a new key pair for the daemon. This is a prerequisite before
4812 archives can be exported with @option{--export}. This
4813 operation is usually instantaneous but it can take time if the system's
4814 entropy pool needs to be refilled. On Guix System,
4815 @code{guix-service-type} takes care of generating this key pair the
4818 The generated key pair is typically stored under @file{/etc/guix}, in
4819 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
4820 key, which must be kept secret). When @var{parameters} is omitted,
4821 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
4822 versions before 1.6.0, it is a 4096-bit RSA key.
4823 Alternatively, @var{parameters} can specify
4824 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
4825 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
4826 Libgcrypt Reference Manual}).
4829 @cindex authorizing, archives
4830 Authorize imports signed by the public key passed on standard input.
4831 The public key must be in ``s-expression advanced format''---i.e., the
4832 same format as the @file{signing-key.pub} file.
4834 The list of authorized keys is kept in the human-editable file
4835 @file{/etc/guix/acl}. The file contains
4836 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
4837 s-expressions''} and is structured as an access-control list in the
4838 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
4841 @item --extract=@var{directory}
4842 @itemx -x @var{directory}
4843 Read a single-item archive as served by substitute servers
4844 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
4845 low-level operation needed in only very narrow use cases; see below.
4847 For example, the following command extracts the substitute for Emacs
4848 served by @code{@value{SUBSTITUTE-SERVER}} to @file{/tmp/emacs}:
4852 https://@value{SUBSTITUTE-SERVER}/nar/gzip/@dots{}-emacs-24.5 \
4853 | gunzip | guix archive -x /tmp/emacs
4856 Single-item archives are different from multiple-item archives produced
4857 by @command{guix archive --export}; they contain a single store item,
4858 and they do @emph{not} embed a signature. Thus this operation does
4859 @emph{no} signature verification and its output should be considered
4862 The primary purpose of this operation is to facilitate inspection of
4863 archive contents coming from possibly untrusted substitute servers
4864 (@pxref{Invoking guix challenge}).
4868 Read a single-item archive as served by substitute servers
4869 (@pxref{Substitutes}) and print the list of files it contains, as in
4874 https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-emacs-26.3 \
4875 | lzip -d | guix archive -t
4880 @c *********************************************************************
4885 @cindex @file{channels.scm}, configuration file
4886 @cindex configuration file for channels
4887 @cindex @command{guix pull}, configuration file
4888 @cindex configuration of @command{guix pull}
4889 Guix and its package collection are updated by running @command{guix pull}
4890 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
4891 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
4892 customized by defining @dfn{channels} in the
4893 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
4894 of a Git repository to be deployed, and @command{guix pull} can be instructed
4895 to pull from one or more channels. In other words, channels can be used
4896 to @emph{customize} and to @emph{extend} Guix, as we will see below.
4897 Guix is able to take into account security concerns and deal with authenticated
4901 * Specifying Additional Channels:: Extending the package collection.
4902 * Using a Custom Guix Channel:: Using a customized Guix.
4903 * Replicating Guix:: Running the @emph{exact same} Guix.
4904 * Channel Authentication:: How Guix verifies what it fetches.
4905 * Creating a Channel:: How to write your custom channel.
4906 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
4907 * Declaring Channel Dependencies:: How to depend on other channels.
4908 * Specifying Channel Authorizations:: Defining channel authors authorizations.
4909 * Primary URL:: Distinguishing mirror to original.
4910 * Writing Channel News:: Communicating information to channel's users.
4913 @node Specifying Additional Channels
4914 @section Specifying Additional Channels
4916 @cindex extending the package collection (channels)
4917 @cindex variant packages (channels)
4918 You can specify @emph{additional channels} to pull from. To use a channel, write
4919 @code{~/.config/guix/channels.scm} to instruct @command{guix pull} to pull from it
4920 @emph{in addition} to the default Guix channel(s):
4922 @vindex %default-channels
4924 ;; Add variant packages to those Guix provides.
4926 (name 'variant-packages)
4927 (url "https://example.org/variant-packages.git"))
4932 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
4933 add a channel the list of channels that the variable @code{%default-channels}
4934 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
4935 Manual}). With this file in place, @command{guix pull} builds not only Guix
4936 but also the package modules from your own repository. The result in
4937 @file{~/.config/guix/current} is the union of Guix with your own package
4941 $ guix pull --list-generations
4943 Generation 19 Aug 27 2018 16:20:48
4945 repository URL: https://git.savannah.gnu.org/git/guix.git
4947 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
4948 variant-packages dd3df5e
4949 repository URL: https://example.org/variant-packages.git
4951 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
4952 11 new packages: variant-gimp, variant-emacs-with-cool-features, @dots{}
4953 4 packages upgraded: emacs-racket-mode@@0.0.2-2.1b78827, @dots{}
4957 The output of @command{guix pull} above shows that Generation@tie{}19 includes
4958 both Guix and packages from the @code{variant-personal-packages} channel. Among
4959 the new and upgraded packages that are listed, some like @code{variant-gimp} and
4960 @code{variant-emacs-with-cool-features} might come from
4961 @code{variant-packages}, while others come from the Guix default channel.
4963 @node Using a Custom Guix Channel
4964 @section Using a Custom Guix Channel
4966 The channel called @code{guix} specifies where Guix itself---its command-line
4967 tools as well as its package collection---should be downloaded. For instance,
4968 suppose you want to update from another copy of the Guix repository at
4969 @code{example.org}, and specifically the @code{super-hacks} branch, you can
4970 write in @code{~/.config/guix/channels.scm} this specification:
4973 ;; Tell 'guix pull' to use another repo.
4976 (url "https://example.org/another-guix.git")
4977 (branch "super-hacks")))
4981 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
4982 branch of the repository at @code{example.org}. The authentication concern is
4983 addressed below ((@pxref{Channel Authentication}).
4985 @node Replicating Guix
4986 @section Replicating Guix
4988 @cindex pinning, channels
4989 @cindex replicating Guix
4990 @cindex reproducibility, of Guix
4991 The @command{guix pull --list-generations} output above shows precisely which
4992 commits were used to build this instance of Guix. We can thus replicate it,
4993 say, on another machine, by providing a channel specification in
4994 @file{~/.config/guix/channels.scm} that is ``pinned'' to these commits:
4997 ;; Deploy specific commits of my channels of interest.
5000 (url "https://git.savannah.gnu.org/git/guix.git")
5001 (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
5003 (name 'variant-packages)
5004 (url "https://example.org/variant-packages.git")
5005 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
5008 The @command{guix describe --format=channels} command can even generate this
5009 list of channels directly (@pxref{Invoking guix describe}). The resulting
5010 file can be used with the -C options of @command{guix pull}
5011 (@pxref{Invoking guix pull}) or @command{guix time-machine}
5012 (@pxref{Invoking guix time-machine}).
5014 At this point the two machines run the @emph{exact same Guix}, with access to
5015 the @emph{exact same packages}. The output of @command{guix build gimp} on
5016 one machine will be exactly the same, bit for bit, as the output of the same
5017 command on the other machine. It also means both machines have access to all
5018 the source code of Guix and, transitively, to all the source code of every
5021 This gives you super powers, allowing you to track the provenance of binary
5022 artifacts with very fine grain, and to reproduce software environments at
5023 will---some sort of ``meta reproducibility'' capabilities, if you will.
5024 @xref{Inferiors}, for another way to take advantage of these super powers.
5026 @node Channel Authentication
5027 @section Channel Authentication
5029 @anchor{channel-authentication}
5030 @cindex authentication, of channel code
5031 The @command{guix pull} and @command{guix time-machine} commands
5032 @dfn{authenticate} the code retrieved from channels: they make sure each
5033 commit that is fetched is signed by an authorized developer. The goal
5034 is to protect from unauthorized modifications to the channel that would
5035 lead users to run malicious code.
5037 As a user, you must provide a @dfn{channel introduction} in your
5038 channels file so that Guix knows how to authenticate its first commit.
5039 A channel specification, including its introduction, looks something
5044 (name 'some-channel)
5045 (url "https://example.org/some-channel.git")
5047 (make-channel-introduction
5048 "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
5049 (openpgp-fingerprint
5050 "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5053 The specification above shows the name and URL of the channel. The call
5054 to @code{make-channel-introduction} above specifies that authentication
5055 of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
5056 by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
5058 For the main channel, called @code{guix}, you automatically get that
5059 information from your Guix installation. For other channels, include
5060 the channel introduction provided by the channel authors in your
5061 @file{channels.scm} file. Make sure you retrieve the channel
5062 introduction from a trusted source since that is the root of your trust.
5064 If you're curious about the authentication mechanics, read on!
5066 @node Creating a Channel
5067 @section Creating a Channel
5069 @cindex personal packages (channels)
5070 @cindex channels, for personal packages
5071 Let's say you have a bunch of custom package variants or personal packages
5072 that you think would make little sense to contribute to the Guix project, but
5073 would like to have these packages transparently available to you at the
5074 command line. You would first write modules containing those package
5075 definitions (@pxref{Package Modules}), maintain them in a Git repository, and
5076 then you and anyone else can use it as an additional channel to get packages
5079 @c What follows stems from discussions at
5080 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
5081 @c earlier discussions on guix-devel@gnu.org.
5083 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
5084 publish your personal channel to the world, we would like to share a few words
5089 Before publishing a channel, please consider contributing your package
5090 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
5091 to free software of all sorts, and packages in Guix proper are readily
5092 available to all Guix users and benefit from the project's quality assurance
5096 When you maintain package definitions outside Guix, we, Guix developers,
5097 consider that @emph{the compatibility burden is on you}. Remember that
5098 package modules and package definitions are just Scheme code that uses various
5099 programming interfaces (APIs). We want to remain free to change these APIs to
5100 keep improving Guix, possibly in ways that break your channel. We never
5101 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
5105 Corollary: if you're using an external channel and that channel breaks, please
5106 @emph{report the issue to the channel authors}, not to the Guix project.
5109 You've been warned! Having said this, we believe external channels are a
5110 practical way to exert your freedom to augment Guix' package collection and to
5111 share your improvements, which are basic tenets of
5112 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
5113 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
5116 To create a channel, create a Git repository containing your own package
5117 modules and make it available. The repository can contain anything, but a
5118 useful channel will contain Guile modules that export packages. Once you
5119 start using a channel, Guix will behave as if the root directory of that
5120 channel's Git repository has been added to the Guile load path (@pxref{Load
5121 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
5122 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
5123 module, then the module will be available under the name @code{(my-packages
5124 my-tools)}, and you will be able to use it like any other module
5125 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
5127 As a channel author, consider bundling authentication material with your
5128 channel so that users can authenticate it. @xref{Channel
5129 Authentication}, and @ref{Specifying Channel Authorizations}, for info
5133 @node Package Modules in a Sub-directory
5134 @section Package Modules in a Sub-directory
5136 @cindex subdirectory, channels
5137 As a channel author, you may want to keep your channel modules in a
5138 sub-directory. If your modules are in the sub-directory @file{guix}, you must
5139 add a meta-data file @file{.guix-channel} that contains:
5147 @node Declaring Channel Dependencies
5148 @section Declaring Channel Dependencies
5150 @cindex dependencies, channels
5151 @cindex meta-data, channels
5152 Channel authors may decide to augment a package collection provided by other
5153 channels. They can declare their channel to be dependent on other channels in
5154 a meta-data file @file{.guix-channel}, which is to be placed in the root of
5155 the channel repository.
5157 The meta-data file should contain a simple S-expression like this:
5164 (name 'some-collection)
5165 (url "https://example.org/first-collection.git")
5167 ;; The 'introduction' bit below is optional: you would
5168 ;; provide it for dependencies that can be authenticated.
5170 (channel-introduction
5172 (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
5173 (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5175 (name 'some-other-collection)
5176 (url "https://example.org/second-collection.git")
5177 (branch "testing"))))
5180 In the above example this channel is declared to depend on two other channels,
5181 which will both be fetched automatically. The modules provided by the channel
5182 will be compiled in an environment where the modules of all these declared
5183 channels are available.
5185 For the sake of reliability and maintainability, you should avoid dependencies
5186 on channels that you don't control, and you should aim to keep the number of
5187 dependencies to a minimum.
5189 @node Specifying Channel Authorizations
5190 @section Specifying Channel Authorizations
5192 @cindex channel authorizations
5193 @anchor{channel-authorizations}
5194 As we saw above, Guix ensures the source code it pulls from channels
5195 comes from authorized developers. As a channel author, you need to
5196 specify the list of authorized developers in the
5197 @file{.guix-authorizations} file in the channel's Git repository. The
5198 authentication rule is simple: each commit must be signed by a key
5199 listed in the @file{.guix-authorizations} file of its parent
5200 commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
5201 (DAG). Each commit can have zero or more parents; ``regular'' commits
5202 have one parent and merge commits have two parent commits. Read
5203 @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
5204 for Computer Scientists}} for a great overview.} The
5205 @file{.guix-authorizations} file looks like this:
5208 ;; Example '.guix-authorizations' file.
5211 (version 0) ;current file format version
5213 (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
5215 ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
5217 ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
5221 Each fingerprint is followed by optional key/value pairs, as in the
5222 example above. Currently these key/value pairs are ignored.
5224 This authentication rule creates a chicken-and-egg issue: how do we
5225 authenticate the first commit? Related to that: how do we deal with
5226 channels whose repository history contains unsigned commits and lack
5227 @file{.guix-authorizations}? And how do we fork existing channels?
5229 @cindex channel introduction
5230 Channel introductions answer these questions by describing the first
5231 commit of a channel that should be authenticated. The first time a
5232 channel is fetched with @command{guix pull} or @command{guix
5233 time-machine}, the command looks up the introductory commit and verifies
5234 that it is signed by the specified OpenPGP key. From then on, it
5235 authenticates commits according to the rule above.
5237 Additionally, your channel must provide all the OpenPGP keys that were
5238 ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
5239 files, which can be either binary or ``ASCII-armored''. By default,
5240 those @file{.key} files are searched for in the branch named
5241 @code{keyring} but you can specify a different branch name in
5242 @code{.guix-channel} like so:
5247 (keyring-reference "my-keyring-branch"))
5250 To summarize, as the author of a channel, there are three things you have
5251 to do to allow users to authenticate your code:
5255 Export the OpenPGP keys of past and present committers with @command{gpg
5256 --export} and store them in @file{.key} files, by default in a branch
5257 named @code{keyring} (we recommend making it an @dfn{orphan branch}).
5260 Introduce an initial @file{.guix-authorizations} in the channel's
5261 repository. Do that in a signed commit (@pxref{Commit Access}, for
5262 information on how to sign Git commits.)
5265 Advertise the channel introduction, for instance on your channel's web
5266 page. The channel introduction, as we saw above, is the commit/key
5267 pair---i.e., the commit that introduced @file{.guix-authorizations}, and
5268 the fingerprint of the OpenPGP used to sign it.
5271 Before pushing to your public Git repository, you can run @command{guix
5272 git-authenticate} to verify that you did sign all the commits you are
5273 about to push with an authorized key:
5276 guix git authenticate @var{commit} @var{signer}
5280 where @var{commit} and @var{signer} are your channel introduction.
5281 @xref{Invoking guix git authenticate}, for details.
5283 Publishing a signed channel requires discipline: any mistake, such as an
5284 unsigned commit or a commit signed by an unauthorized key, will prevent
5285 users from pulling from your channel---well, that's the whole point of
5286 authentication! Pay attention to merges in particular: merge commits
5287 are considered authentic if and only if they are signed by a key present
5288 in the @file{.guix-authorizations} file of @emph{both} branches.
5291 @section Primary URL
5293 @cindex primary URL, channels
5294 Channel authors can indicate the primary URL of their channel's Git
5295 repository in the @file{.guix-channel} file, like so:
5300 (url "https://example.org/guix.git"))
5303 This allows @command{guix pull} to determine whether it is pulling code
5304 from a mirror of the channel; when that is the case, it warns the user
5305 that the mirror might be stale and displays the primary URL. That way,
5306 users cannot be tricked into fetching code from a stale mirror that does
5307 not receive security updates.
5309 This feature only makes sense for authenticated repositories, such as
5310 the official @code{guix} channel, for which @command{guix pull} ensures
5311 the code it fetches is authentic.
5313 @node Writing Channel News
5314 @section Writing Channel News
5316 @cindex news, for channels
5317 Channel authors may occasionally want to communicate to their users
5318 information about important changes in the channel. You'd send them all
5319 an email, but that's not convenient.
5321 Instead, channels can provide a @dfn{news file}; when the channel users
5322 run @command{guix pull}, that news file is automatically read and
5323 @command{guix pull --news} can display the announcements that correspond
5324 to the new commits that have been pulled, if any.
5326 To do that, channel authors must first declare the name of the news file
5327 in their @file{.guix-channel} file:
5332 (news-file "etc/news.txt"))
5335 The news file itself, @file{etc/news.txt} in this example, must look
5336 something like this:
5341 (entry (tag "the-bug-fix")
5342 (title (en "Fixed terrible bug")
5344 (body (en "@@emph@{Good news@}! It's fixed!")
5345 (eo "Certe ĝi pli bone funkcias nun!")))
5346 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
5347 (title (en "Added a great package")
5348 (ca "Què vol dir guix?"))
5349 (body (en "Don't miss the @@code@{hello@} package!"))))
5352 While the news file is using the Scheme syntax, avoid naming it with a
5353 @file{.scm} extension or else it will get picked up when building the
5354 channel and yield an error since it is not a valid module.
5355 Alternatively, you can move the channel module to a subdirectory and
5356 store the news file in another directory.
5358 The file consists of a list of @dfn{news entries}. Each entry is
5359 associated with a commit or tag: it describes changes made in this
5360 commit, possibly in preceding commits as well. Users see entries only
5361 the first time they obtain the commit the entry refers to.
5363 The @code{title} field should be a one-line summary while @code{body}
5364 can be arbitrarily long, and both can contain Texinfo markup
5365 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
5366 a list of language tag/message tuples, which allows @command{guix pull}
5367 to display news in the language that corresponds to the user's locale.
5369 If you want to translate news using a gettext-based workflow, you can
5370 extract translatable strings with @command{xgettext} (@pxref{xgettext
5371 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
5372 you write news entries in English first, the command below creates a PO
5373 file containing the strings to translate:
5376 xgettext -o news.po -l scheme -ken etc/news.txt
5379 To sum up, yes, you could use your channel as a blog. But beware, this
5380 is @emph{not quite} what your users might expect.
5383 @c *********************************************************************
5385 @chapter Development
5387 @cindex software development
5388 If you are a software developer, Guix provides tools that you should find
5389 helpful---independently of the language you're developing in. This is what
5390 this chapter is about.
5392 The @command{guix environment} command provides a convenient way to set up
5393 @dfn{development environments} containing all the dependencies and tools
5394 necessary to work on the software package of your choice. The @command{guix
5395 pack} command allows you to create @dfn{application bundles} that can be
5396 easily distributed to users who do not run Guix.
5399 * Invoking guix environment:: Setting up development environments.
5400 * Invoking guix pack:: Creating software bundles.
5401 * The GCC toolchain:: Working with languages supported by GCC.
5402 * Invoking guix git authenticate:: Authenticating Git repositories.
5405 @node Invoking guix environment
5406 @section Invoking @command{guix environment}
5408 @cindex reproducible build environments
5409 @cindex development environments
5410 @cindex @command{guix environment}
5411 @cindex environment, package build environment
5412 The purpose of @command{guix environment} is to assist hackers in
5413 creating reproducible development environments without polluting their
5414 package profile. The @command{guix environment} tool takes one or more
5415 packages, builds all of their inputs, and creates a shell
5416 environment to use them.
5418 The general syntax is:
5421 guix environment @var{options} @var{package}@dots{}
5424 The following example spawns a new shell set up for the development of
5428 guix environment guile
5431 If the needed dependencies are not built yet, @command{guix environment}
5432 automatically builds them. The environment of the new shell is an
5433 augmented version of the environment that @command{guix environment} was
5434 run in. It contains the necessary search paths for building the given
5435 package added to the existing environment variables. To create
5436 a ``pure'' environment, in which the original environment variables have
5437 been unset, use the @option{--pure} option@footnote{Users sometimes
5438 wrongfully augment environment variables such as @env{PATH} in their
5439 @file{~/.bashrc} file. As a consequence, when @command{guix
5440 environment} launches it, Bash may read @file{~/.bashrc}, thereby
5441 introducing ``impurities'' in these environment variables. It is an
5442 error to define such environment variables in @file{.bashrc}; instead,
5443 they should be defined in @file{.bash_profile}, which is sourced only by
5444 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
5445 Manual}, for details on Bash start-up files.}.
5447 @vindex GUIX_ENVIRONMENT
5448 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
5449 variable in the shell it spawns; its value is the file name of the
5450 profile of this environment. This allows users to, say, define a
5451 specific prompt for development environments in their @file{.bashrc}
5452 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
5455 if [ -n "$GUIX_ENVIRONMENT" ]
5457 export PS1="\u@@\h \w [dev]\$ "
5462 ...@: or to browse the profile:
5465 $ ls "$GUIX_ENVIRONMENT/bin"
5468 Additionally, more than one package may be specified, in which case the
5469 union of the inputs for the given packages are used. For example, the
5470 command below spawns a shell where all of the dependencies of both Guile
5471 and Emacs are available:
5474 guix environment guile emacs
5477 Sometimes an interactive shell session is not desired. An arbitrary
5478 command may be invoked by placing the @code{--} token to separate the
5479 command from the rest of the arguments:
5482 guix environment guile -- make -j4
5485 In other situations, it is more convenient to specify the list of
5486 packages needed in the environment. For example, the following command
5487 runs @command{python} from an environment containing Python@tie{}2.7 and
5491 guix environment --ad-hoc python2-numpy python-2.7 -- python
5494 Furthermore, one might want the dependencies of a package and also some
5495 additional packages that are not build-time or runtime dependencies, but
5496 are useful when developing nonetheless. Because of this, the
5497 @option{--ad-hoc} flag is positional. Packages appearing before
5498 @option{--ad-hoc} are interpreted as packages whose dependencies will be
5499 added to the environment. Packages appearing after are interpreted as
5500 packages that will be added to the environment directly. For example,
5501 the following command creates a Guix development environment that
5502 additionally includes Git and strace:
5505 guix environment --pure guix --ad-hoc git strace
5509 Sometimes it is desirable to isolate the environment as much as
5510 possible, for maximal purity and reproducibility. In particular, when
5511 using Guix on a host distro that is not Guix System, it is desirable to
5512 prevent access to @file{/usr/bin} and other system-wide resources from
5513 the development environment. For example, the following command spawns
5514 a Guile REPL in a ``container'' where only the store and the current
5515 working directory are mounted:
5518 guix environment --ad-hoc --container guile -- guile
5522 The @option{--container} option requires Linux-libre 3.19 or newer.
5525 @cindex certificates
5526 Another typical use case for containers is to run security-sensitive
5527 applications such as a web browser. To run Eolie, we must expose and
5528 share some files and directories; we include @code{nss-certs} and expose
5529 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
5530 @env{DISPLAY} environment variable since containerized graphical
5531 applications won't display without it.
5534 guix environment --preserve='^DISPLAY$' --container --network \
5535 --expose=/etc/machine-id \
5536 --expose=/etc/ssl/certs/ \
5537 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
5538 --ad-hoc eolie nss-certs dbus -- eolie
5541 The available options are summarized below.
5544 @item --root=@var{file}
5545 @itemx -r @var{file}
5546 @cindex persistent environment
5547 @cindex garbage collector root, for environments
5548 Make @var{file} a symlink to the profile for this environment, and
5549 register it as a garbage collector root.
5551 This is useful if you want to protect your environment from garbage
5552 collection, to make it ``persistent''.
5554 When this option is omitted, the environment is protected from garbage
5555 collection only for the duration of the @command{guix environment}
5556 session. This means that next time you recreate the same environment,
5557 you could have to rebuild or re-download packages. @xref{Invoking guix
5558 gc}, for more on GC roots.
5560 @item --expression=@var{expr}
5561 @itemx -e @var{expr}
5562 Create an environment for the package or list of packages that
5563 @var{expr} evaluates to.
5565 For example, running:
5568 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
5571 starts a shell with the environment for this specific variant of the
5577 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
5580 starts a shell with all the base system packages available.
5582 The above commands only use the default output of the given packages.
5583 To select other outputs, two element tuples can be specified:
5586 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
5589 @item --load=@var{file}
5590 @itemx -l @var{file}
5591 Create an environment for the package or list of packages that the code
5592 within @var{file} evaluates to.
5594 As an example, @var{file} might contain a definition like this
5595 (@pxref{Defining Packages}):
5598 @verbatiminclude environment-gdb.scm
5601 @item --manifest=@var{file}
5602 @itemx -m @var{file}
5603 Create an environment for the packages contained in the manifest object
5604 returned by the Scheme code in @var{file}. This option can be repeated
5605 several times, in which case the manifests are concatenated.
5607 This is similar to the same-named option in @command{guix package}
5608 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
5612 Include all specified packages in the resulting environment, as if an
5613 @i{ad hoc} package were defined with them as inputs. This option is
5614 useful for quickly creating an environment without having to write a
5615 package expression to contain the desired inputs.
5617 For instance, the command:
5620 guix environment --ad-hoc guile guile-sdl -- guile
5623 runs @command{guile} in an environment where Guile and Guile-SDL are
5626 Note that this example implicitly asks for the default output of
5627 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
5628 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
5629 of @code{glib} (@pxref{Packages with Multiple Outputs}).
5631 This option may be composed with the default behavior of @command{guix
5632 environment}. Packages appearing before @option{--ad-hoc} are
5633 interpreted as packages whose dependencies will be added to the
5634 environment, the default behavior. Packages appearing after are
5635 interpreted as packages that will be added to the environment directly.
5638 Unset existing environment variables when building the new environment, except
5639 those specified with @option{--preserve} (see below). This has the effect of
5640 creating an environment in which search paths only contain package inputs.
5642 @item --preserve=@var{regexp}
5643 @itemx -E @var{regexp}
5644 When used alongside @option{--pure}, preserve the environment variables
5645 matching @var{regexp}---in other words, put them on a ``white list'' of
5646 environment variables that must be preserved. This option can be repeated
5650 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
5654 This example runs @command{mpirun} in a context where the only environment
5655 variables defined are @env{PATH}, environment variables whose name starts
5656 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
5659 @item --search-paths
5660 Display the environment variable definitions that make up the
5663 @item --system=@var{system}
5664 @itemx -s @var{system}
5665 Attempt to build for @var{system}---e.g., @code{i686-linux}.
5670 Run @var{command} within an isolated container. The current working
5671 directory outside the container is mapped inside the container.
5672 Additionally, unless overridden with @option{--user}, a dummy home
5673 directory is created that matches the current user's home directory, and
5674 @file{/etc/passwd} is configured accordingly.
5676 The spawned process runs as the current user outside the container. Inside
5677 the container, it has the same UID and GID as the current user, unless
5678 @option{--user} is passed (see below).
5682 For containers, share the network namespace with the host system.
5683 Containers created without this flag only have access to the loopback
5686 @item --link-profile
5688 For containers, link the environment profile to @file{~/.guix-profile}
5689 within the container and set @code{GUIX_ENVIRONMENT} to that.
5690 This is equivalent to making @file{~/.guix-profile} a symlink to the
5691 actual profile within the container.
5692 Linking will fail and abort the environment if the directory already
5693 exists, which will certainly be the case if @command{guix environment}
5694 was invoked in the user's home directory.
5696 Certain packages are configured to look in @file{~/.guix-profile} for
5697 configuration files and data;@footnote{For example, the
5698 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
5699 for additional fonts.} @option{--link-profile} allows these programs to
5700 behave as expected within the environment.
5702 @item --user=@var{user}
5703 @itemx -u @var{user}
5704 For containers, use the username @var{user} in place of the current
5705 user. The generated @file{/etc/passwd} entry within the container will
5706 contain the name @var{user}, the home directory will be
5707 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
5708 the UID and GID inside the container are 1000. @var{user}
5709 need not exist on the system.
5711 Additionally, any shared or exposed path (see @option{--share} and
5712 @option{--expose} respectively) whose target is within the current user's
5713 home directory will be remapped relative to @file{/home/USER}; this
5714 includes the automatic mapping of the current working directory.
5717 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
5719 guix environment --container --user=foo \
5720 --expose=$HOME/test \
5721 --expose=/tmp/target=$HOME/target
5724 While this will limit the leaking of user identity through home paths
5725 and each of the user fields, this is only one useful component of a
5726 broader privacy/anonymity solution---not one in and of itself.
5729 For containers, the default behavior is to share the current working
5730 directory with the isolated container and immediately change to that
5731 directory within the container. If this is undesirable,
5732 @option{--no-cwd} will cause the current working directory to @emph{not}
5733 be automatically shared and will change to the user's home directory
5734 within the container instead. See also @option{--user}.
5736 @item --expose=@var{source}[=@var{target}]
5737 @itemx --share=@var{source}[=@var{target}]
5738 For containers, @option{--expose} (resp. @option{--share}) exposes the
5739 file system @var{source} from the host system as the read-only
5740 (resp. writable) file system @var{target} within the container. If
5741 @var{target} is not specified, @var{source} is used as the target mount
5742 point in the container.
5744 The example below spawns a Guile REPL in a container in which the user's
5745 home directory is accessible read-only via the @file{/exchange}
5749 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
5754 @command{guix environment}
5755 also supports all of the common build options that @command{guix
5756 build} supports (@pxref{Common Build Options}) as well as package
5757 transformation options (@pxref{Package Transformation Options}).
5759 @node Invoking guix pack
5760 @section Invoking @command{guix pack}
5762 Occasionally you want to pass software to people who are not (yet!)
5763 lucky enough to be using Guix. You'd tell them to run @command{guix
5764 package -i @var{something}}, but that's not possible in this case. This
5765 is where @command{guix pack} comes in.
5768 If you are looking for ways to exchange binaries among machines that
5769 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
5770 publish}, and @ref{Invoking guix archive}.
5775 @cindex application bundle
5776 @cindex software bundle
5777 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
5778 @dfn{software bundle}: it creates a tarball or some other archive
5779 containing the binaries of the software you're interested in, and all
5780 its dependencies. The resulting archive can be used on any machine that
5781 does not have Guix, and people can run the exact same binaries as those
5782 you have with Guix. The pack itself is created in a bit-reproducible
5783 fashion, so anyone can verify that it really contains the build results
5784 that you pretend to be shipping.
5786 For example, to create a bundle containing Guile, Emacs, Geiser, and all
5787 their dependencies, you can run:
5790 $ guix pack guile emacs geiser
5792 /gnu/store/@dots{}-pack.tar.gz
5795 The result here is a tarball containing a @file{/gnu/store} directory
5796 with all the relevant packages. The resulting tarball contains a
5797 @dfn{profile} with the three packages of interest; the profile is the
5798 same as would be created by @command{guix package -i}. It is this
5799 mechanism that is used to create Guix's own standalone binary tarball
5800 (@pxref{Binary Installation}).
5802 Users of this pack would have to run
5803 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
5804 find inconvenient. To work around it, you can create, say, a
5805 @file{/opt/gnu/bin} symlink to the profile:
5808 guix pack -S /opt/gnu/bin=bin guile emacs geiser
5812 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
5814 @cindex relocatable binaries, with @command{guix pack}
5815 What if the recipient of your pack does not have root privileges on
5816 their machine, and thus cannot unpack it in the root file system? In
5817 that case, you will want to use the @option{--relocatable} option (see
5818 below). This option produces @dfn{relocatable binaries}, meaning they
5819 they can be placed anywhere in the file system hierarchy: in the example
5820 above, users can unpack your tarball in their home directory and
5821 directly run @file{./opt/gnu/bin/guile}.
5823 @cindex Docker, build an image with guix pack
5824 Alternatively, you can produce a pack in the Docker image format using
5825 the following command:
5828 guix pack -f docker -S /bin=bin guile guile-readline
5832 The result is a tarball that can be passed to the @command{docker load}
5833 command, followed by @code{docker run}:
5836 docker load < @var{file}
5837 docker run -ti guile-guile-readline /bin/guile
5841 where @var{file} is the image returned by @var{guix pack}, and
5842 @code{guile-guile-readline} is its ``image tag''. See the
5843 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
5844 documentation} for more information.
5846 @cindex Singularity, build an image with guix pack
5847 @cindex SquashFS, build an image with guix pack
5848 Yet another option is to produce a SquashFS image with the following
5852 guix pack -f squashfs bash guile emacs geiser
5856 The result is a SquashFS file system image that can either be mounted or
5857 directly be used as a file system container image with the
5858 @uref{https://www.sylabs.io/docs/, Singularity container execution
5859 environment}, using commands like @command{singularity shell} or
5860 @command{singularity exec}.
5862 Several command-line options allow you to customize your pack:
5865 @item --format=@var{format}
5866 @itemx -f @var{format}
5867 Produce a pack in the given @var{format}.
5869 The available formats are:
5873 This is the default format. It produces a tarball containing all the
5874 specified binaries and symlinks.
5877 This produces a tarball that follows the
5878 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
5879 Docker Image Specification}. The ``repository name'' as it appears in
5880 the output of the @command{docker images} command is computed from
5881 package names passed on the command line or in the manifest file.
5884 This produces a SquashFS image containing all the specified binaries and
5885 symlinks, as well as empty mount points for virtual file systems like
5889 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
5890 For that reason, @command{guix pack -f squashfs} always implies @code{-S
5891 /bin=bin}. Thus, your @command{guix pack} invocation must always start
5892 with something like:
5895 guix pack -f squashfs bash @dots{}
5898 If you forget the @code{bash} (or similar) package, @command{singularity
5899 run} and @command{singularity exec} will fail with an unhelpful ``no
5900 such file or directory'' message.
5904 @cindex relocatable binaries
5907 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
5908 anywhere in the file system hierarchy and run from there.
5910 When this option is passed once, the resulting binaries require support for
5911 @dfn{user namespaces} in the kernel Linux; when passed
5912 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
5913 PRoot support, can be thought of as the abbreviation of ``Really
5914 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
5915 other techniques if user namespaces are unavailable, and essentially
5916 work anywhere---see below for the implications.
5918 For example, if you create a pack containing Bash with:
5921 guix pack -RR -S /mybin=bin bash
5925 ...@: you can copy that pack to a machine that lacks Guix, and from your
5926 home directory as a normal user, run:
5934 In that shell, if you type @code{ls /gnu/store}, you'll notice that
5935 @file{/gnu/store} shows up and contains all the dependencies of
5936 @code{bash}, even though the machine actually lacks @file{/gnu/store}
5937 altogether! That is probably the simplest way to deploy Guix-built
5938 software on a non-Guix machine.
5941 By default, relocatable binaries rely on the @dfn{user namespace} feature of
5942 the kernel Linux, which allows unprivileged users to mount or change root.
5943 Old versions of Linux did not support it, and some GNU/Linux distributions
5946 To produce relocatable binaries that work even in the absence of user
5947 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
5948 case, binaries will try user namespace support and fall back to another
5949 @dfn{execution engine} if user namespaces are not supported. The
5950 following execution engines are supported:
5954 Try user namespaces and fall back to PRoot if user namespaces are not
5955 supported (see below).
5958 Try user namespaces and fall back to Fakechroot if user namespaces are
5959 not supported (see below).
5962 Run the program through user namespaces and abort if they are not
5966 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
5967 provides the necessary
5968 support for file system virtualization. It achieves that by using the
5969 @code{ptrace} system call on the running program. This approach has the
5970 advantage to work without requiring special kernel support, but it incurs
5971 run-time overhead every time a system call is made.
5974 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
5975 Fakechroot} virtualizes file system accesses by intercepting calls to C
5976 library functions such as @code{open}, @code{stat}, @code{exec}, and so
5977 on. Unlike PRoot, it incurs very little overhead. However, it does not
5978 always work: for example, some file system accesses made from within the
5979 C library are not intercepted, and file system accesses made @i{via}
5980 direct syscalls are not intercepted either, leading to erratic behavior.
5983 @vindex GUIX_EXECUTION_ENGINE
5984 When running a wrapped program, you can explicitly request one of the
5985 execution engines listed above by setting the
5986 @env{GUIX_EXECUTION_ENGINE} environment variable accordingly.
5989 @cindex entry point, for Docker images
5990 @item --entry-point=@var{command}
5991 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
5992 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
5993 support it. @var{command} must be relative to the profile contained in the
5996 The entry point specifies the command that tools like @code{docker run} or
5997 @code{singularity run} automatically start by default. For example, you can
6001 guix pack -f docker --entry-point=bin/guile guile
6004 The resulting pack can easily be loaded and @code{docker run} with no extra
6005 arguments will spawn @code{bin/guile}:
6008 docker load -i pack.tar.gz
6009 docker run @var{image-id}
6012 @item --expression=@var{expr}
6013 @itemx -e @var{expr}
6014 Consider the package @var{expr} evaluates to.
6016 This has the same purpose as the same-named option in @command{guix
6017 build} (@pxref{Additional Build Options, @option{--expression} in
6018 @command{guix build}}).
6020 @item --manifest=@var{file}
6021 @itemx -m @var{file}
6022 Use the packages contained in the manifest object returned by the Scheme
6023 code in @var{file}. This option can be repeated several times, in which
6024 case the manifests are concatenated.
6026 This has a similar purpose as the same-named option in @command{guix
6027 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
6028 same manifest files. It allows you to define a collection of packages
6029 once and use it both for creating profiles and for creating archives
6030 for use on machines that do not have Guix installed. Note that you can
6031 specify @emph{either} a manifest file @emph{or} a list of packages,
6034 @item --system=@var{system}
6035 @itemx -s @var{system}
6036 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
6037 the system type of the build host.
6039 @item --target=@var{triplet}
6040 @cindex cross-compilation
6041 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
6042 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
6043 configuration triplets,, autoconf, Autoconf}).
6045 @item --compression=@var{tool}
6046 @itemx -C @var{tool}
6047 Compress the resulting tarball using @var{tool}---one of @code{gzip},
6048 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
6051 @item --symlink=@var{spec}
6052 @itemx -S @var{spec}
6053 Add the symlinks specified by @var{spec} to the pack. This option can
6054 appear several times.
6056 @var{spec} has the form @code{@var{source}=@var{target}}, where
6057 @var{source} is the symlink that will be created and @var{target} is the
6060 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
6061 symlink pointing to the @file{bin} sub-directory of the profile.
6063 @item --save-provenance
6064 Save provenance information for the packages passed on the command line.
6065 Provenance information includes the URL and commit of the channels in use
6068 Provenance information is saved in the
6069 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
6070 usual package metadata---the name and version of each package, their
6071 propagated inputs, and so on. It is useful information to the recipient of
6072 the pack, who then knows how the pack was (supposedly) obtained.
6074 This option is not enabled by default because, like timestamps, provenance
6075 information contributes nothing to the build process. In other words, there
6076 is an infinity of channel URLs and commit IDs that can lead to the same pack.
6077 Recording such ``silent'' metadata in the output thus potentially breaks the
6078 source-to-binary bitwise reproducibility property.
6080 @item --root=@var{file}
6081 @itemx -r @var{file}
6082 @cindex garbage collector root, for packs
6083 Make @var{file} a symlink to the resulting pack, and register it as a garbage
6086 @item --localstatedir
6087 @itemx --profile-name=@var{name}
6088 Include the ``local state directory'', @file{/var/guix}, in the resulting
6089 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
6090 profile---by default @var{name} is @code{guix-profile}, which corresponds to
6091 @file{~root/.guix-profile}.
6093 @file{/var/guix} contains the store database (@pxref{The Store}) as well
6094 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
6095 the pack means that the store is ``complete'' and manageable by Guix;
6096 not providing it pack means that the store is ``dead'': items cannot be
6097 added to it or removed from it after extraction of the pack.
6099 One use case for this is the Guix self-contained binary tarball
6100 (@pxref{Binary Installation}).
6104 Print the name of the derivation that builds the pack.
6107 Use the bootstrap binaries to build the pack. This option is only
6108 useful to Guix developers.
6111 In addition, @command{guix pack} supports all the common build options
6112 (@pxref{Common Build Options}) and all the package transformation
6113 options (@pxref{Package Transformation Options}).
6116 @node The GCC toolchain
6117 @section The GCC toolchain
6121 @cindex linker wrapper
6122 @cindex toolchain, for C development
6123 @cindex toolchain, for Fortran development
6125 If you need a complete toolchain for compiling and linking C or C++
6126 source code, use the @code{gcc-toolchain} package. This package
6127 provides a complete GCC toolchain for C/C++ development, including GCC
6128 itself, the GNU C Library (headers and binaries, plus debugging symbols
6129 in the @code{debug} output), Binutils, and a linker wrapper.
6131 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
6132 passed to the linker, add corresponding @code{-rpath} arguments, and
6133 invoke the actual linker with this new set of arguments. You can instruct the
6134 wrapper to refuse to link against libraries not in the store by setting the
6135 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
6137 The package @code{gfortran-toolchain} provides a complete GCC toolchain
6138 for Fortran development. For other languages, please use
6139 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
6142 @node Invoking guix git authenticate
6143 @section Invoking @command{guix git authenticate}
6145 The @command{guix git authenticate} command authenticates a Git checkout
6146 following the same rule as for channels (@pxref{channel-authentication,
6147 channel authentication}). That is, starting from a given commit, it
6148 ensures that all subsequent commits are signed by an OpenPGP key whose
6149 fingerprint appears in the @file{.guix-authorizations} file of its
6152 You will find this command useful if you maintain a channel. But in
6153 fact, this authentication mechanism is useful in a broader context, so
6154 you might want to use it for Git repositories that have nothing to do
6157 The general syntax is:
6160 guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
6163 By default, this command authenticates the Git checkout in the current
6164 directory; it outputs nothing and exits with exit code zero on success
6165 and non-zero on failure. @var{commit} above denotes the first commit
6166 where authentication takes place, and @var{signer} is the OpenPGP
6167 fingerprint of public key used to sign @var{commit}. Together, they
6168 form a ``channel introduction'' (@pxref{channel-authentication, channel
6169 introduction}). The options below allow you to fine-tune the process.
6172 @item --repository=@var{directory}
6173 @itemx -r @var{directory}
6174 Open the Git repository in @var{directory} instead of the current
6177 @item --keyring=@var{reference}
6178 @itemx -k @var{reference}
6179 Load OpenPGP keyring from @var{reference}, the reference of a branch
6180 such as @code{origin/keyring} or @code{my-keyring}. The branch must
6181 contain OpenPGP public keys in @file{.key} files, either in binary form
6182 or ``ASCII-armored''. By default the keyring is loaded from the branch
6183 named @code{keyring}.
6186 Display commit signing statistics upon completion.
6188 @item --cache-key=@var{key}
6189 Previously-authenticated commits are cached in a file under
6190 @file{~/.cache/guix/authentication}. This option forces the cache to be
6191 stored in file @var{key} in that directory.
6193 @item --historical-authorizations=@var{file}
6194 By default, any commit whose parent commit(s) lack the
6195 @file{.guix-authorizations} file is considered inauthentic. In
6196 contrast, this option considers the authorizations in @var{file} for any
6197 commit that lacks @file{.guix-authorizations}. The format of @var{file}
6198 is the same as that of @file{.guix-authorizations}
6199 (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
6203 @c *********************************************************************
6204 @node Programming Interface
6205 @chapter Programming Interface
6207 GNU Guix provides several Scheme programming interfaces (APIs) to
6208 define, build, and query packages. The first interface allows users to
6209 write high-level package definitions. These definitions refer to
6210 familiar packaging concepts, such as the name and version of a package,
6211 its build system, and its dependencies. These definitions can then be
6212 turned into concrete build actions.
6214 Build actions are performed by the Guix daemon, on behalf of users. In a
6215 standard setup, the daemon has write access to the store---the
6216 @file{/gnu/store} directory---whereas users do not. The recommended
6217 setup also has the daemon perform builds in chroots, under specific
6218 build users, to minimize interference with the rest of the system.
6221 Lower-level APIs are available to interact with the daemon and the
6222 store. To instruct the daemon to perform a build action, users actually
6223 provide it with a @dfn{derivation}. A derivation is a low-level
6224 representation of the build actions to be taken, and the environment in
6225 which they should occur---derivations are to package definitions what
6226 assembly is to C programs. The term ``derivation'' comes from the fact
6227 that build results @emph{derive} from them.
6229 This chapter describes all these APIs in turn, starting from high-level
6230 package definitions.
6233 * Package Modules:: Packages from the programmer's viewpoint.
6234 * Defining Packages:: Defining new packages.
6235 * Defining Package Variants:: Customizing packages.
6236 * Build Systems:: Specifying how packages are built.
6237 * Build Phases:: Phases of the build process of a package.
6238 * Build Utilities:: Helpers for your package definitions and more.
6239 * The Store:: Manipulating the package store.
6240 * Derivations:: Low-level interface to package derivations.
6241 * The Store Monad:: Purely functional interface to the store.
6242 * G-Expressions:: Manipulating build expressions.
6243 * Invoking guix repl:: Programming Guix in Guile
6246 @node Package Modules
6247 @section Package Modules
6249 From a programming viewpoint, the package definitions of the
6250 GNU distribution are provided by Guile modules in the @code{(gnu packages
6251 @dots{})} name space@footnote{Note that packages under the @code{(gnu
6252 packages @dots{})} module name space are not necessarily ``GNU
6253 packages''. This module naming scheme follows the usual Guile module
6254 naming convention: @code{gnu} means that these modules are distributed
6255 as part of the GNU system, and @code{packages} identifies modules that
6256 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
6257 Reference Manual}). For instance, the @code{(gnu packages emacs)}
6258 module exports a variable named @code{emacs}, which is bound to a
6259 @code{<package>} object (@pxref{Defining Packages}).
6261 The @code{(gnu packages @dots{})} module name space is
6262 automatically scanned for packages by the command-line tools. For
6263 instance, when running @code{guix install emacs}, all the @code{(gnu
6264 packages @dots{})} modules are scanned until one that exports a package
6265 object whose name is @code{emacs} is found. This package search
6266 facility is implemented in the @code{(gnu packages)} module.
6268 @cindex customization, of packages
6269 @cindex package module search path
6270 Users can store package definitions in modules with different
6271 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
6272 name and module name must match. For instance, the @code{(my-packages
6273 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
6274 relative to the load path specified with @option{--load-path} or
6275 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
6276 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
6277 these package definitions visible to the user interfaces:
6281 By adding the directory containing your package modules to the search path
6282 with the @code{-L} flag of @command{guix package} and other commands
6283 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
6284 environment variable described below.
6287 By defining a @dfn{channel} and configuring @command{guix pull} so that it
6288 pulls from it. A channel is essentially a Git repository containing package
6289 modules. @xref{Channels}, for more information on how to define and use
6293 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
6295 @defvr {Environment Variable} GUIX_PACKAGE_PATH
6296 This is a colon-separated list of directories to search for additional
6297 package modules. Directories listed in this variable take precedence
6298 over the own modules of the distribution.
6301 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
6302 each package is built based solely on other packages in the
6303 distribution. The root of this dependency graph is a small set of
6304 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
6305 bootstrap)} module. For more information on bootstrapping,
6306 @pxref{Bootstrapping}.
6308 @node Defining Packages
6309 @section Defining Packages
6311 The high-level interface to package definitions is implemented in the
6312 @code{(guix packages)} and @code{(guix build-system)} modules. As an
6313 example, the package definition, or @dfn{recipe}, for the GNU Hello
6314 package looks like this:
6317 (define-module (gnu packages hello)
6318 #:use-module (guix packages)
6319 #:use-module (guix download)
6320 #:use-module (guix build-system gnu)
6321 #:use-module (guix licenses)
6322 #:use-module (gnu packages gawk))
6324 (define-public hello
6330 (uri (string-append "mirror://gnu/hello/hello-" version
6334 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
6335 (build-system gnu-build-system)
6336 (arguments '(#:configure-flags '("--enable-silent-rules")))
6337 (inputs `(("gawk" ,gawk)))
6338 (synopsis "Hello, GNU world: An example GNU package")
6339 (description "Guess what GNU Hello prints!")
6340 (home-page "https://www.gnu.org/software/hello/")
6345 Without being a Scheme expert, the reader may have guessed the meaning
6346 of the various fields here. This expression binds the variable
6347 @code{hello} to a @code{<package>} object, which is essentially a record
6348 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
6349 This package object can be inspected using procedures found in the
6350 @code{(guix packages)} module; for instance, @code{(package-name hello)}
6351 returns---surprise!---@code{"hello"}.
6353 With luck, you may be able to import part or all of the definition of
6354 the package you are interested in from another repository, using the
6355 @code{guix import} command (@pxref{Invoking guix import}).
6357 In the example above, @code{hello} is defined in a module of its own,
6358 @code{(gnu packages hello)}. Technically, this is not strictly
6359 necessary, but it is convenient to do so: all the packages defined in
6360 modules under @code{(gnu packages @dots{})} are automatically known to
6361 the command-line tools (@pxref{Package Modules}).
6363 There are a few points worth noting in the above package definition:
6367 The @code{source} field of the package is an @code{<origin>} object
6368 (@pxref{origin Reference}, for the complete reference).
6369 Here, the @code{url-fetch} method from @code{(guix download)} is used,
6370 meaning that the source is a file to be downloaded over FTP or HTTP.
6372 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
6373 the GNU mirrors defined in @code{(guix download)}.
6375 The @code{sha256} field specifies the expected SHA256 hash of the file
6376 being downloaded. It is mandatory, and allows Guix to check the
6377 integrity of the file. The @code{(base32 @dots{})} form introduces the
6378 base32 representation of the hash. You can obtain this information with
6379 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
6380 hash} (@pxref{Invoking guix hash}).
6383 When needed, the @code{origin} form can also have a @code{patches} field
6384 listing patches to be applied, and a @code{snippet} field giving a
6385 Scheme expression to modify the source code.
6388 @cindex GNU Build System
6389 The @code{build-system} field specifies the procedure to build the
6390 package (@pxref{Build Systems}). Here, @code{gnu-build-system}
6391 represents the familiar GNU Build System, where packages may be
6392 configured, built, and installed with the usual @code{./configure &&
6393 make && make check && make install} command sequence.
6395 When you start packaging non-trivial software, you may need tools to
6396 manipulate those build phases, manipulate files, and so on. @xref{Build
6397 Utilities}, for more on this.
6400 The @code{arguments} field specifies options for the build system
6401 (@pxref{Build Systems}). Here it is interpreted by
6402 @code{gnu-build-system} as a request run @file{configure} with the
6403 @option{--enable-silent-rules} flag.
6409 What about these quote (@code{'}) characters? They are Scheme syntax to
6410 introduce a literal list; @code{'} is synonymous with @code{quote}.
6411 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
6412 for details. Here the value of the @code{arguments} field is a list of
6413 arguments passed to the build system down the road, as with @code{apply}
6414 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
6417 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
6418 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
6419 @code{#:configure-flags} is a keyword used to pass a keyword argument
6420 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
6424 The @code{inputs} field specifies inputs to the build process---i.e.,
6425 build-time or run-time dependencies of the package. Here, we define an
6426 input called @code{"gawk"} whose value is that of the @code{gawk}
6427 variable; @code{gawk} is itself bound to a @code{<package>} object.
6429 @cindex backquote (quasiquote)
6432 @cindex comma (unquote)
6436 @findex unquote-splicing
6437 Again, @code{`} (a backquote, synonymous with @code{quasiquote}) allows
6438 us to introduce a literal list in the @code{inputs} field, while
6439 @code{,} (a comma, synonymous with @code{unquote}) allows us to insert a
6440 value in that list (@pxref{Expression Syntax, unquote,, guile, GNU Guile
6443 Note that GCC, Coreutils, Bash, and other essential tools do not need to
6444 be specified as inputs here. Instead, @code{gnu-build-system} takes care
6445 of ensuring that they are present (@pxref{Build Systems}).
6447 However, any other dependencies need to be specified in the
6448 @code{inputs} field. Any dependency not specified here will simply be
6449 unavailable to the build process, possibly leading to a build failure.
6452 @xref{package Reference}, for a full description of possible fields.
6454 Once a package definition is in place, the
6455 package may actually be built using the @code{guix build} command-line
6456 tool (@pxref{Invoking guix build}), troubleshooting any build failures
6457 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
6458 package definition using the @command{guix edit} command
6459 (@pxref{Invoking guix edit}).
6460 @xref{Packaging Guidelines}, for
6461 more information on how to test package definitions, and
6462 @ref{Invoking guix lint}, for information on how to check a definition
6463 for style conformance.
6464 @vindex GUIX_PACKAGE_PATH
6465 Lastly, @pxref{Channels}, for information
6466 on how to extend the distribution by adding your own package definitions
6469 Finally, updating the package definition to a new upstream version
6470 can be partly automated by the @command{guix refresh} command
6471 (@pxref{Invoking guix refresh}).
6473 Behind the scenes, a derivation corresponding to the @code{<package>}
6474 object is first computed by the @code{package-derivation} procedure.
6475 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
6476 The build actions it prescribes may then be realized by using the
6477 @code{build-derivations} procedure (@pxref{The Store}).
6479 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
6480 Return the @code{<derivation>} object of @var{package} for @var{system}
6481 (@pxref{Derivations}).
6483 @var{package} must be a valid @code{<package>} object, and @var{system}
6484 must be a string denoting the target system type---e.g.,
6485 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
6486 must be a connection to the daemon, which operates on the store
6487 (@pxref{The Store}).
6491 @cindex cross-compilation
6492 Similarly, it is possible to compute a derivation that cross-builds a
6493 package for some other system:
6495 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
6496 @var{package} @var{target} [@var{system}]
6497 Return the @code{<derivation>} object of @var{package} cross-built from
6498 @var{system} to @var{target}.
6500 @var{target} must be a valid GNU triplet denoting the target hardware
6501 and operating system, such as @code{"aarch64-linux-gnu"}
6502 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
6505 Once you have package definitions, you can easily define @emph{variants}
6506 of those packages. @xref{Defining Package Variants}, for more on that.
6509 * package Reference:: The package data type.
6510 * origin Reference:: The origin data type.
6514 @node package Reference
6515 @subsection @code{package} Reference
6517 This section summarizes all the options available in @code{package}
6518 declarations (@pxref{Defining Packages}).
6520 @deftp {Data Type} package
6521 This is the data type representing a package recipe.
6525 The name of the package, as a string.
6527 @item @code{version}
6528 The version of the package, as a string.
6531 An object telling how the source code for the package should be
6532 acquired. Most of the time, this is an @code{origin} object, which
6533 denotes a file fetched from the Internet (@pxref{origin Reference}). It
6534 can also be any other ``file-like'' object such as a @code{local-file},
6535 which denotes a file from the local file system (@pxref{G-Expressions,
6536 @code{local-file}}).
6538 @item @code{build-system}
6539 The build system that should be used to build the package (@pxref{Build
6542 @item @code{arguments} (default: @code{'()})
6543 The arguments that should be passed to the build system. This is a
6544 list, typically containing sequential keyword-value pairs.
6546 @item @code{inputs} (default: @code{'()})
6547 @itemx @code{native-inputs} (default: @code{'()})
6548 @itemx @code{propagated-inputs} (default: @code{'()})
6549 @cindex inputs, of packages
6550 These fields list dependencies of the package. Each one is a list of
6551 tuples, where each tuple has a label for the input (a string) as its
6552 first element, a package, origin, or derivation as its second element,
6553 and optionally the name of the output thereof that should be used, which
6554 defaults to @code{"out"} (@pxref{Packages with Multiple Outputs}, for
6555 more on package outputs). For example, the list below specifies three
6559 `(("libffi" ,libffi)
6560 ("libunistring" ,libunistring)
6561 ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
6564 @cindex cross compilation, package dependencies
6565 The distinction between @code{native-inputs} and @code{inputs} is
6566 necessary when considering cross-compilation. When cross-compiling,
6567 dependencies listed in @code{inputs} are built for the @emph{target}
6568 architecture; conversely, dependencies listed in @code{native-inputs}
6569 are built for the architecture of the @emph{build} machine.
6571 @code{native-inputs} is typically used to list tools needed at
6572 build time, but not at run time, such as Autoconf, Automake, pkg-config,
6573 Gettext, or Bison. @command{guix lint} can report likely mistakes in
6574 this area (@pxref{Invoking guix lint}).
6576 @anchor{package-propagated-inputs}
6577 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
6578 specified packages will be automatically installed to profiles
6579 (@pxref{Features, the role of profiles in Guix}) alongside the package
6580 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
6581 package}}, for information on how @command{guix package} deals with
6584 For example this is necessary when packaging a C/C++ library that needs
6585 headers of another library to compile, or when a pkg-config file refers
6586 to another one @i{via} its @code{Requires} field.
6588 Another example where @code{propagated-inputs} is useful is for languages
6589 that lack a facility to record the run-time search path akin to the
6590 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
6591 more. When packaging libraries written in those languages, ensure they
6592 can find library code they depend on at run time by listing run-time
6593 dependencies in @code{propagated-inputs} rather than @code{inputs}.
6595 @item @code{outputs} (default: @code{'("out")})
6596 The list of output names of the package. @xref{Packages with Multiple
6597 Outputs}, for typical uses of additional outputs.
6599 @item @code{native-search-paths} (default: @code{'()})
6600 @itemx @code{search-paths} (default: @code{'()})
6601 A list of @code{search-path-specification} objects describing
6602 search-path environment variables honored by the package.
6604 @item @code{replacement} (default: @code{#f})
6605 This must be either @code{#f} or a package object that will be used as a
6606 @dfn{replacement} for this package. @xref{Security Updates, grafts},
6609 @item @code{synopsis}
6610 A one-line description of the package.
6612 @item @code{description}
6613 A more elaborate description of the package.
6615 @item @code{license}
6616 @cindex license, of packages
6617 The license of the package; a value from @code{(guix licenses)},
6618 or a list of such values.
6620 @item @code{home-page}
6621 The URL to the home-page of the package, as a string.
6623 @item @code{supported-systems} (default: @code{%supported-systems})
6624 The list of systems supported by the package, as strings of the form
6625 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
6627 @item @code{location} (default: source location of the @code{package} form)
6628 The source location of the package. It is useful to override this when
6629 inheriting from another package, in which case this field is not
6630 automatically corrected.
6634 @deffn {Scheme Syntax} this-package
6635 When used in the @emph{lexical scope} of a package field definition, this
6636 identifier resolves to the package being defined.
6638 The example below shows how to add a package as a native input of itself when
6646 ;; When cross-compiled, Guile, for example, depends on
6647 ;; a native version of itself. Add it here.
6648 (native-inputs (if (%current-target-system)
6649 `(("self" ,this-package))
6653 It is an error to refer to @code{this-package} outside a package definition.
6656 Because packages are regular Scheme objects that capture a complete
6657 dependency graph and associated build procedures, it is often useful to
6658 write procedures that take a package and return a modified version
6659 thereof according to some parameters. Below are a few examples.
6661 @cindex tool chain, choosing a package's tool chain
6662 @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
6663 Return a variant of @var{package} that uses @var{toolchain} instead of
6664 the default GNU C/C++ toolchain. @var{toolchain} must be a list of
6665 inputs (label/package tuples) providing equivalent functionality, such
6666 as the @code{gcc-toolchain} package.
6668 The example below returns a variant of the @code{hello} package built
6669 with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
6670 GNU C Library) instead of the default tool chain:
6673 (let ((toolchain (specification->package "gcc-toolchain@@10")))
6674 (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
6677 The build tool chain is part of the @dfn{implicit inputs} of
6678 packages---it's usually not listed as part of the various ``inputs''
6679 fields and is instead pulled in by the build system. Consequently, this
6680 procedure works by changing the build system of @var{package} so that it
6681 pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
6682 for more on build systems.
6685 @node origin Reference
6686 @subsection @code{origin} Reference
6688 This section documents @dfn{origins}. An @code{origin} declaration
6689 specifies data that must be ``produced''---downloaded, usually---and
6690 whose content hash is known in advance. Origins are primarily used to
6691 represent the source code of packages (@pxref{Defining Packages}). For
6692 that reason, the @code{origin} form allows you to declare patches to
6693 apply to the original source code as well as code snippets to modify it.
6695 @deftp {Data Type} origin
6696 This is the data type representing a source code origin.
6700 An object containing the URI of the source. The object type depends on
6701 the @code{method} (see below). For example, when using the
6702 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
6703 values are: a URL represented as a string, or a list thereof.
6705 @cindex fixed-output derivations, for download
6707 A monadic procedure that handles the given URI. The procedure must
6708 accept at least three arguments: the value of the @code{uri} field and
6709 the hash algorithm and hash value specified by the @code{hash} field.
6710 It must return a store item or a derivation in the store monad
6711 (@pxref{The Store Monad}); most methods return a fixed-output derivation
6712 (@pxref{Derivations}).
6714 Commonly used methods include @code{url-fetch}, which fetches data from
6715 a URL, and @code{git-fetch}, which fetches data from a Git repository
6719 A bytevector containing the SHA-256 hash of the source. This is
6720 equivalent to providing a @code{content-hash} SHA256 object in the
6721 @code{hash} field described below.
6724 The @code{content-hash} object of the source---see below for how to use
6725 @code{content-hash}.
6727 You can obtain this information using @code{guix download}
6728 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
6731 @item @code{file-name} (default: @code{#f})
6732 The file name under which the source code should be saved. When this is
6733 @code{#f}, a sensible default value will be used in most cases. In case
6734 the source is fetched from a URL, the file name from the URL will be
6735 used. For version control checkouts, it is recommended to provide the
6736 file name explicitly because the default is not very descriptive.
6738 @item @code{patches} (default: @code{'()})
6739 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
6740 file-like objects}) pointing to patches to be applied to the source.
6742 This list of patches must be unconditional. In particular, it cannot
6743 depend on the value of @code{%current-system} or
6744 @code{%current-target-system}.
6746 @item @code{snippet} (default: @code{#f})
6747 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
6748 in the source directory. This is a convenient way to modify the source,
6749 sometimes more convenient than a patch.
6751 @item @code{patch-flags} (default: @code{'("-p1")})
6752 A list of command-line flags that should be passed to the @code{patch}
6755 @item @code{patch-inputs} (default: @code{#f})
6756 Input packages or derivations to the patching process. When this is
6757 @code{#f}, the usual set of inputs necessary for patching are provided,
6758 such as GNU@tie{}Patch.
6760 @item @code{modules} (default: @code{'()})
6761 A list of Guile modules that should be loaded during the patching
6762 process and while running the code in the @code{snippet} field.
6764 @item @code{patch-guile} (default: @code{#f})
6765 The Guile package that should be used in the patching process. When
6766 this is @code{#f}, a sensible default is used.
6770 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
6771 Construct a content hash object for the given @var{algorithm}, and with
6772 @var{value} as its hash value. When @var{algorithm} is omitted, assume
6773 it is @code{sha256}.
6775 @var{value} can be a literal string, in which case it is base32-decoded,
6776 or it can be a bytevector.
6778 The following forms are all equivalent:
6781 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
6782 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
6784 (content-hash (base32
6785 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
6786 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
6790 Technically, @code{content-hash} is currently implemented as a macro.
6791 It performs sanity checks at macro-expansion time, when possible, such
6792 as ensuring that @var{value} has the right size for @var{algorithm}.
6795 As we have seen above, how exactly the data an origin refers to is
6796 retrieved is determined by its @code{method} field. The @code{(guix
6797 download)} module provides the most common method, @code{url-fetch},
6800 @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
6801 [name] [#:executable? #f]
6802 Return a fixed-output derivation that fetches data from @var{url} (a
6803 string, or a list of strings denoting alternate URLs), which is expected
6804 to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
6805 the file name is the base name of URL; optionally, @var{name} can
6806 specify a different file name. When @var{executable?} is true, make the
6807 downloaded file executable.
6809 When one of the URL starts with @code{mirror://}, then its host part is
6810 interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
6812 Alternatively, when URL starts with @code{file://}, return the
6813 corresponding file name in the store.
6816 Likewise, the @code{(guix git-download)} module defines the
6817 @code{git-fetch} origin method, which fetches data from a Git version
6818 control repository, and the @code{git-reference} data type to describe
6819 the repository and revision to fetch.
6821 @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
6822 Return a fixed-output derivation that fetches @var{ref}, a
6823 @code{<git-reference>} object. The output is expected to have recursive
6824 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
6825 the file name, or a generic name if @code{#f}.
6828 @deftp {Data Type} git-reference
6829 This data type represents a Git reference for @code{git-fetch} to
6834 The URL of the Git repository to clone.
6837 This string denotes either the commit to fetch (a hexadecimal string,
6838 either the full SHA1 commit or a ``short'' commit string; the latter is
6839 not recommended) or the tag to fetch.
6841 @item @code{recursive?} (default: @code{#f})
6842 This Boolean indicates whether to recursively fetch Git sub-modules.
6845 The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
6850 (url "https://git.savannah.gnu.org/git/hello.git")
6854 This is equivalent to the reference below, which explicitly names the
6859 (url "https://git.savannah.gnu.org/git/hello.git")
6860 (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
6864 For Mercurial repositories, the module @code{(guix hg-download)} defines
6865 the @code{hg-fetch} origin method and @code{hg-reference} data type for
6866 support of the Mercurial version control system.
6868 @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
6870 Return a fixed-output derivation that fetches @var{ref}, a
6871 @code{<hg-reference>} object. The output is expected to have recursive
6872 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
6873 the file name, or a generic name if @code{#false}.
6876 @node Defining Package Variants
6877 @section Defining Package Variants
6879 @cindex customizing packages
6880 @cindex variants, of packages
6881 One of the nice things with Guix is that, given a package definition,
6882 you can easily @emph{derive} variants of that package---for a different
6883 upstream version, with different dependencies, different compilation
6884 options, and so on. Some of these custom packages can be defined
6885 straight from the command line (@pxref{Package Transformation Options}).
6886 This section describes how to define package variants in code. This can
6887 be useful in ``manifests'' (@pxref{profile-manifest,
6888 @option{--manifest}}) and in your own package collection
6889 (@pxref{Creating a Channel}), among others!
6891 @cindex inherit, for package definitions
6892 As discussed earlier, packages are first-class objects in the Scheme
6893 language. The @code{(guix packages)} module provides the @code{package}
6894 construct to define new package objects (@pxref{package Reference}).
6895 The easiest way to define a package variant is using the @code{inherit}
6896 keyword together with @code{package}. This allows you to inherit from a
6897 package definition while overriding the fields you want.
6899 For example, given the @code{hello} variable, which contains a
6900 definition for the current version of GNU@tie{}Hello, here's how you
6901 would define a variant for version 2.2 (released in 2006, it's
6905 (use-modules (gnu packages base)) ;for 'hello'
6913 (uri (string-append "mirror://gnu/hello/hello-" version
6917 "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
6920 The example above corresponds to what the @option{--with-source} package
6921 transformation option does. Essentially @code{hello-2.2} preserves all
6922 the fields of @code{hello}, except @code{version} and @code{source},
6923 which it overrides. Note that the original @code{hello} variable is
6924 still there, in the @code{(gnu packages base)} module, unchanged. When
6925 you define a custom package like this, you are really @emph{adding} a
6926 new package definition; the original one remains available.
6928 You can just as well define variants with a different set of
6929 dependencies than the original package. For example, the default
6930 @code{gdb} package depends on @code{guile}, but since that is an
6931 optional dependency, you can define a variant that removes that
6935 (use-modules (gnu packages gdb) ;for 'gdb'
6936 (srfi srfi-1)) ;for 'alist-delete'
6938 (define gdb-sans-guile
6941 (inputs (alist-delete "guile"
6942 (package-inputs gdb)))))
6945 The @code{alist-delete} call above removes the tuple from the
6946 @code{inputs} field that has @code{"guile"} as its first element
6947 (@pxref{SRFI-1 Association Lists,,, guile, GNU Guile Reference
6950 In some cases, you may find it useful to write functions
6951 (``procedures'', in Scheme parlance) that return a package based on some
6952 parameters. For example, consider the @code{luasocket} library for the
6953 Lua programming language. We want to create @code{luasocket} packages
6954 for major versions of Lua. One way to do that is to define a procedure
6955 that takes a Lua package and returns a @code{luasocket} package that
6959 (define (make-lua-socket name lua)
6960 ;; Return a luasocket package built with LUA.
6964 ;; several fields omitted
6967 (synopsis "Socket library for Lua")))
6969 (define-public lua5.1-socket
6970 (make-lua-socket "lua5.1-socket" lua-5.1))
6972 (define-public lua5.2-socket
6973 (make-lua-socket "lua5.2-socket" lua-5.2))
6976 Here we have defined packages @code{lua5.1-socket} and
6977 @code{lua5.2-socket} by calling @code{make-lua-socket} with different
6978 arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
6979 more info on procedures. Having top-level public definitions for these
6980 two packages means that they can be referred to from the command line
6981 (@pxref{Package Modules}).
6983 @cindex package transformations
6984 These are pretty simple package variants. As a convenience, the
6985 @code{(guix transformations)} module provides a high-level interface
6986 that directly maps to the more sophisticated package transformation
6987 options (@pxref{Package Transformation Options}):
6989 @deffn {Scheme Procedure} options->transformation @var{opts}
6990 Return a procedure that, when passed an object to build (package,
6991 derivation, etc.), applies the transformations specified by @var{opts} and returns
6992 the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
6995 ((with-branch . "guile-gcrypt=master")
6996 (without-tests . "libgcrypt"))
6999 Each symbol names a transformation and the corresponding string is an argument
7000 to that transformation.
7003 For instance, a manifest equivalent to this command:
7007 --with-branch=guile-gcrypt=master \
7008 --with-debug-info=zlib
7012 ... would look like this:
7015 (use-modules (guix transformations))
7018 ;; The package transformation procedure.
7019 (options->transformation
7020 '((with-branch . "guile-gcrypt=master")
7021 (with-debug-info . "zlib"))))
7024 (list (transform (specification->package "guix"))))
7027 @cindex input rewriting
7028 @cindex dependency graph rewriting
7029 The @code{options->transformation} procedure is convenient, but it's
7030 perhaps also not as flexible as you may like. How is it implemented?
7031 The astute reader probably noticed that most package transformation
7032 options go beyond the superficial changes shown in the first examples of
7033 this section: they involve @dfn{input rewriting}, whereby the dependency
7034 graph of a package is rewritten by replacing specific inputs by others.
7036 Dependency graph rewriting, for the purposes of swapping packages in the
7037 graph, is what the @code{package-input-rewriting} procedure in
7038 @code{(guix packages)} implements.
7040 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
7041 [@var{rewrite-name}] [#:deep? #t]
7042 Return a procedure that, when passed a package, replaces its direct and
7043 indirect dependencies, including implicit inputs when @var{deep?} is
7044 true, according to @var{replacements}. @var{replacements} is a list of
7045 package pairs; the first element of each pair is the package to replace,
7046 and the second one is the replacement.
7048 Optionally, @var{rewrite-name} is a one-argument procedure that takes
7049 the name of a package and returns its new name after rewrite.
7053 Consider this example:
7056 (define libressl-instead-of-openssl
7057 ;; This is a procedure to replace OPENSSL by LIBRESSL,
7059 (package-input-rewriting `((,openssl . ,libressl))))
7061 (define git-with-libressl
7062 (libressl-instead-of-openssl git))
7066 Here we first define a rewriting procedure that replaces @var{openssl}
7067 with @var{libressl}. Then we use it to define a @dfn{variant} of the
7068 @var{git} package that uses @var{libressl} instead of @var{openssl}.
7069 This is exactly what the @option{--with-input} command-line option does
7070 (@pxref{Package Transformation Options, @option{--with-input}}).
7072 The following variant of @code{package-input-rewriting} can match packages to
7073 be replaced by name rather than by identity.
7075 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
7076 Return a procedure that, given a package, applies the given
7077 @var{replacements} to all the package graph, including implicit inputs
7078 unless @var{deep?} is false. @var{replacements} is a list of
7079 spec/procedures pair; each spec is a package specification such as
7080 @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
7081 package and returns a replacement for that package.
7084 The example above could be rewritten this way:
7087 (define libressl-instead-of-openssl
7088 ;; Replace all the packages called "openssl" with LibreSSL.
7089 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
7092 The key difference here is that, this time, packages are matched by spec and
7093 not by identity. In other words, any package in the graph that is called
7094 @code{openssl} will be replaced.
7096 A more generic procedure to rewrite a package dependency graph is
7097 @code{package-mapping}: it supports arbitrary changes to nodes in the
7100 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
7101 Return a procedure that, given a package, applies @var{proc} to all the packages
7102 depended on and returns the resulting package. The procedure stops recursion
7103 when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
7104 applied to implicit inputs as well.
7109 @section Build Systems
7111 @cindex build system
7112 Each package definition specifies a @dfn{build system} and arguments for
7113 that build system (@pxref{Defining Packages}). This @code{build-system}
7114 field represents the build procedure of the package, as well as implicit
7115 dependencies of that build procedure.
7117 Build systems are @code{<build-system>} objects. The interface to
7118 create and manipulate them is provided by the @code{(guix build-system)}
7119 module, and actual build systems are exported by specific modules.
7121 @cindex bag (low-level package representation)
7122 Under the hood, build systems first compile package objects to
7123 @dfn{bags}. A @dfn{bag} is like a package, but with less
7124 ornamentation---in other words, a bag is a lower-level representation of
7125 a package, which includes all the inputs of that package, including some
7126 that were implicitly added by the build system. This intermediate
7127 representation is then compiled to a derivation (@pxref{Derivations}).
7128 The @code{package-with-c-toolchain} is an example of a way to change the
7129 implicit inputs that a package's build system pulls in (@pxref{package
7130 Reference, @code{package-with-c-toolchain}}).
7132 Build systems accept an optional list of @dfn{arguments}. In package
7133 definitions, these are passed @i{via} the @code{arguments} field
7134 (@pxref{Defining Packages}). They are typically keyword arguments
7135 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
7136 Guile Reference Manual}). The value of these arguments is usually
7137 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
7138 by the daemon (@pxref{Derivations}).
7140 The main build system is @code{gnu-build-system}, which implements the
7141 standard build procedure for GNU and many other packages. It
7142 is provided by the @code{(guix build-system gnu)} module.
7144 @defvr {Scheme Variable} gnu-build-system
7145 @code{gnu-build-system} represents the GNU Build System, and variants
7146 thereof (@pxref{Configuration, configuration and makefile conventions,,
7147 standards, GNU Coding Standards}).
7149 @cindex build phases
7150 In a nutshell, packages using it are configured, built, and installed with
7151 the usual @code{./configure && make && make check && make install}
7152 command sequence. In practice, a few additional steps are often needed.
7153 All these steps are split up in separate @dfn{phases},
7154 notably@footnote{Please see the @code{(guix build gnu-build-system)}
7155 modules for more details about the build phases.}:
7159 Unpack the source tarball, and change the current directory to the
7160 extracted source tree. If the source is actually a directory, copy it
7161 to the build tree, and enter that directory.
7163 @item patch-source-shebangs
7164 Patch shebangs encountered in source files so they refer to the right
7165 store file names. For instance, this changes @code{#!/bin/sh} to
7166 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
7169 Run the @file{configure} script with a number of default options, such
7170 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
7171 by the @code{#:configure-flags} argument.
7174 Run @code{make} with the list of flags specified with
7175 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
7176 (the default), build with @code{make -j}.
7179 Run @code{make check}, or some other target specified with
7180 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
7181 @code{#:parallel-tests?} argument is true (the default), run @code{make
7185 Run @code{make install} with the flags listed in @code{#:make-flags}.
7187 @item patch-shebangs
7188 Patch shebangs on the installed executable files.
7191 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
7192 is false), copying them to the @code{debug} output when available
7193 (@pxref{Installing Debugging Files}).
7196 @vindex %standard-phases
7197 The build-side module @code{(guix build gnu-build-system)} defines
7198 @code{%standard-phases} as the default list of build phases.
7199 @code{%standard-phases} is a list of symbol/procedure pairs, where the
7200 procedure implements the actual phase.
7202 @xref{Build Phases}, for more info on build phases and ways to customize
7205 In addition, this build system ensures that the ``standard'' environment
7206 for GNU packages is available. This includes tools such as GCC, libc,
7207 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
7208 build-system gnu)} module for a complete list). We call these the
7209 @dfn{implicit inputs} of a package, because package definitions do not
7210 have to mention them.
7213 Other @code{<build-system>} objects are defined to support other
7214 conventions and tools used by free software packages. They inherit most
7215 of @code{gnu-build-system}, and differ mainly in the set of inputs
7216 implicitly added to the build process, and in the list of phases
7217 executed. Some of these build systems are listed below.
7219 @defvr {Scheme Variable} ant-build-system
7220 This variable is exported by @code{(guix build-system ant)}. It
7221 implements the build procedure for Java packages that can be built with
7222 @url{https://ant.apache.org/, Ant build tool}.
7224 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
7225 provided by the @code{icedtea} package to the set of inputs. Different
7226 packages can be specified with the @code{#:ant} and @code{#:jdk}
7227 parameters, respectively.
7229 When the original package does not provide a suitable Ant build file,
7230 the parameter @code{#:jar-name} can be used to generate a minimal Ant
7231 build file @file{build.xml} with tasks to build the specified jar
7232 archive. In this case the parameter @code{#:source-dir} can be used to
7233 specify the source sub-directory, defaulting to ``src''.
7235 The @code{#:main-class} parameter can be used with the minimal ant
7236 buildfile to specify the main class of the resulting jar. This makes the
7237 jar file executable. The @code{#:test-include} parameter can be used to
7238 specify the list of junit tests to run. It defaults to
7239 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
7240 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
7241 because abstract classes cannot be run as tests.
7243 The parameter @code{#:build-target} can be used to specify the Ant task
7244 that should be run during the @code{build} phase. By default the
7245 ``jar'' task will be run.
7249 @defvr {Scheme Variable} android-ndk-build-system
7250 @cindex Android distribution
7251 @cindex Android NDK build system
7252 This variable is exported by @code{(guix build-system android-ndk)}. It
7253 implements a build procedure for Android NDK (native development kit)
7254 packages using a Guix-specific build process.
7256 The build system assumes that packages install their public interface
7257 (header) files to the subdirectory @file{include} of the @code{out} output and
7258 their libraries to the subdirectory @file{lib} the @code{out} output.
7260 It's also assumed that the union of all the dependencies of a package
7261 has no conflicting files.
7263 For the time being, cross-compilation is not supported - so right now
7264 the libraries and header files are assumed to be host tools.
7268 @defvr {Scheme Variable} asdf-build-system/source
7269 @defvrx {Scheme Variable} asdf-build-system/sbcl
7270 @defvrx {Scheme Variable} asdf-build-system/ecl
7272 These variables, exported by @code{(guix build-system asdf)}, implement
7273 build procedures for Common Lisp packages using
7274 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
7275 definition facility for Common Lisp programs and libraries.
7277 The @code{asdf-build-system/source} system installs the packages in
7278 source form, and can be loaded using any common lisp implementation, via
7279 ASDF. The others, such as @code{asdf-build-system/sbcl}, install binary
7280 systems in the format which a particular implementation understands.
7281 These build systems can also be used to produce executable programs, or
7282 lisp images which contain a set of packages pre-loaded.
7284 The build system uses naming conventions. For binary packages, the
7285 package name should be prefixed with the lisp implementation, such as
7286 @code{sbcl-} for @code{asdf-build-system/sbcl}.
7288 Additionally, the corresponding source package should be labeled using
7289 the same convention as python packages (see @ref{Python Modules}), using
7290 the @code{cl-} prefix.
7292 In order to create executable programs and images, the build-side
7293 procedures @code{build-program} and @code{build-image} can be used.
7294 They should be called in a build phase after the
7295 @code{create-asdf-configuration} phase, so that the system which was
7296 just built can be used within the resulting image. @code{build-program}
7297 requires a list of Common Lisp expressions to be passed as the
7298 @code{#:entry-program} argument.
7300 By default, all the @file{.asd} files present in the sources are read to
7301 find system definitions. The @code{#:asd-files} parameter can be used
7302 to specify the list of @file{.asd} files to read. Furthermore, if the
7303 package defines a system for its tests in a separate file, it will be
7304 loaded before the tests are run if it is specified by the
7305 @code{#:test-asd-file} parameter. If it is not set, the files
7306 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
7307 and @code{test.asd} will be tried if they exist.
7309 If for some reason the package must be named in a different way than the
7310 naming conventions suggest, or if several systems must be compiled, the
7311 @code{#:asd-systems} parameter can be used to specify the list of system
7316 @defvr {Scheme Variable} cargo-build-system
7317 @cindex Rust programming language
7318 @cindex Cargo (Rust build system)
7319 This variable is exported by @code{(guix build-system cargo)}. It
7320 supports builds of packages using Cargo, the build tool of the
7321 @uref{https://www.rust-lang.org, Rust programming language}.
7323 It adds @code{rustc} and @code{cargo} to the set of inputs.
7324 A different Rust package can be specified with the @code{#:rust} parameter.
7326 Regular cargo dependencies should be added to the package definition via the
7327 @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
7328 spec can be a package or a source definition. Note that the spec must
7329 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
7330 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
7331 should be added to the package definition via the
7332 @code{#:cargo-development-inputs} parameter.
7334 In its @code{configure} phase, this build system will make any source inputs
7335 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
7336 parameters available to cargo. It will also remove an included
7337 @code{Cargo.lock} file to be recreated by @code{cargo} during the
7338 @code{build} phase. The @code{install} phase installs the binaries
7339 defined by the crate.
7342 @defvr {Scheme Variable} chicken-build-system
7343 This variable is exported by @code{(guix build-system chicken)}. It
7344 builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
7345 ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
7346 gets compiled by a C compiler, in this case GCC.
7348 This build system adds @code{chicken} to the package inputs, as well as
7349 the packages of @code{gnu-build-system}.
7351 The build system can't (yet) deduce the egg's name automatically, so just like
7352 with @code{go-build-system} and its @code{#:import-path}, you should define
7353 @code{#:egg-name} in the package's @code{arguments} field.
7355 For example, if you are packaging the @code{srfi-1} egg:
7358 (arguments '(#:egg-name "srfi-1"))
7361 Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
7362 because CHICKEN doesn't embed absolute references in compiled eggs.
7363 Test dependencies should go to @code{native-inputs}, as usual.
7366 @defvr {Scheme Variable} copy-build-system
7367 This variable is exported by @code{(guix build-system copy)}. It
7368 supports builds of simple packages that don't require much compiling,
7369 mostly just moving files around.
7371 It adds much of the @code{gnu-build-system} packages to the set of
7372 inputs. Because of this, the @code{copy-build-system} does not require
7373 all the boilerplate code often needed for the
7374 @code{trivial-build-system}.
7376 To further simplify the file installation process, an
7377 @code{#:install-plan} argument is exposed to let the packager specify
7378 which files go where. The install plan is a list of @code{(@var{source}
7379 @var{target} [@var{filters}])}. @var{filters} are optional.
7382 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
7384 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
7385 @item Otherwise install @var{source} as @var{target}.
7388 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
7389 the trailing slash of @var{target} is implied with the same meaning
7392 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
7393 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
7394 @code{#:exclude-regexp}, only select files are installed depending on
7395 the filters. Each filters is specified by a list of strings.
7397 @item With @code{#:include}, install all the files which the path suffix matches
7398 at least one of the elements in the given list.
7399 @item With @code{#:include-regexp}, install all the files which the
7400 subpaths match at least one of the regular expressions in the given
7402 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
7403 are the complement of their inclusion counterpart. Without @code{#:include} flags,
7404 install all files but those matching the exclusion filters.
7405 If both inclusions and exclusions are specified, the exclusions are done
7406 on top of the inclusions.
7409 In all cases, the paths relative to @var{source} are preserved within
7416 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
7417 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
7418 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
7419 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
7420 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
7421 @file{share/my-app/sub/file}.
7422 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
7423 @file{share/my-app/file}.
7428 @cindex Clojure (programming language)
7429 @cindex simple Clojure build system
7430 @defvr {Scheme Variable} clojure-build-system
7431 This variable is exported by @code{(guix build-system clojure)}. It implements
7432 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
7433 using plain old @code{compile} in Clojure. Cross-compilation is not supported
7436 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
7437 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
7438 @code{#:zip} parameters, respectively.
7440 A list of source directories, test directories and jar names can be specified
7441 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
7442 parameters, respectively. Compile directory and main class can be specified
7443 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
7444 Other parameters are documented below.
7446 This build system is an extension of @code{ant-build-system}, but with the
7447 following phases changed:
7452 This phase calls @code{compile} in Clojure to compile source files and runs
7453 @command{jar} to create jars from both source files and compiled files
7454 according to the include list and exclude list specified in
7455 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
7456 has priority over the include list. These lists consist of symbols
7457 representing Clojure libraries or the special keyword @code{#:all} representing
7458 all Clojure libraries found under the source directories. The parameter
7459 @code{#:omit-source?} decides if source should be included into the jars.
7462 This phase runs tests according to the include list and exclude list specified
7463 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
7464 meanings are analogous to that of @code{#:aot-include} and
7465 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
7466 stands for all Clojure libraries found under the test directories. The
7467 parameter @code{#:tests?} decides if tests should be run.
7470 This phase installs all jars built previously.
7473 Apart from the above, this build system also contains an additional phase:
7478 This phase installs all top-level files with base name matching
7479 @code{%doc-regex}. A different regex can be specified with the
7480 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
7481 directories specified in @code{#:doc-dirs} are installed as well.
7485 @defvr {Scheme Variable} cmake-build-system
7486 This variable is exported by @code{(guix build-system cmake)}. It
7487 implements the build procedure for packages using the
7488 @url{https://www.cmake.org, CMake build tool}.
7490 It automatically adds the @code{cmake} package to the set of inputs.
7491 Which package is used can be specified with the @code{#:cmake}
7494 The @code{#:configure-flags} parameter is taken as a list of flags
7495 passed to the @command{cmake} command. The @code{#:build-type}
7496 parameter specifies in abstract terms the flags passed to the compiler;
7497 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
7498 debugging information''), which roughly means that code is compiled with
7499 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
7502 @defvr {Scheme Variable} dune-build-system
7503 This variable is exported by @code{(guix build-system dune)}. It
7504 supports builds of packages using @uref{https://dune.build/, Dune}, a build
7505 tool for the OCaml programming language. It is implemented as an extension
7506 of the @code{ocaml-build-system} which is described below. As such, the
7507 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
7510 It automatically adds the @code{dune} package to the set of inputs.
7511 Which package is used can be specified with the @code{#:dune}
7514 There is no @code{configure} phase because dune packages typically don't
7515 need to be configured. The @code{#:build-flags} parameter is taken as a
7516 list of flags passed to the @code{dune} command during the build.
7518 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
7519 command instead of the more recent @code{dune} command while building
7520 a package. Its default value is @code{#f}.
7522 The @code{#:package} parameter can be passed to specify a package name, which
7523 is useful when a package contains multiple packages and you want to build
7524 only one of them. This is equivalent to passing the @code{-p} argument to
7528 @defvr {Scheme Variable} go-build-system
7529 This variable is exported by @code{(guix build-system go)}. It
7530 implements a build procedure for Go packages using the standard
7531 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
7532 Go build mechanisms}.
7534 The user is expected to provide a value for the key @code{#:import-path}
7535 and, in some cases, @code{#:unpack-path}. The
7536 @url{https://golang.org/doc/code.html#ImportPaths, import path}
7537 corresponds to the file system path expected by the package's build
7538 scripts and any referring packages, and provides a unique way to
7539 refer to a Go package. It is typically based on a combination of the
7540 package source code's remote URI and file system hierarchy structure. In
7541 some cases, you will need to unpack the package's source code to a
7542 different directory structure than the one indicated by the import path,
7543 and @code{#:unpack-path} should be used in such cases.
7545 Packages that provide Go libraries should install their source code into
7546 the built output. The key @code{#:install-source?}, which defaults to
7547 @code{#t}, controls whether or not the source code is installed. It can
7548 be set to @code{#f} for packages that only provide executable files.
7551 @defvr {Scheme Variable} glib-or-gtk-build-system
7552 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
7553 is intended for use with packages making use of GLib or GTK+.
7555 This build system adds the following two phases to the ones defined by
7556 @code{gnu-build-system}:
7559 @item glib-or-gtk-wrap
7560 The phase @code{glib-or-gtk-wrap} ensures that programs in
7561 @file{bin/} are able to find GLib ``schemas'' and
7562 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
7563 modules}. This is achieved by wrapping the programs in launch scripts
7564 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
7565 environment variables.
7567 It is possible to exclude specific package outputs from that wrapping
7568 process by listing their names in the
7569 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
7570 when an output is known not to contain any GLib or GTK+ binaries, and
7571 where wrapping would gratuitously add a dependency of that output on
7574 @item glib-or-gtk-compile-schemas
7575 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
7576 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
7577 GSettings schemas} of GLib are compiled. Compilation is performed by the
7578 @command{glib-compile-schemas} program. It is provided by the package
7579 @code{glib:bin} which is automatically imported by the build system.
7580 The @code{glib} package providing @command{glib-compile-schemas} can be
7581 specified with the @code{#:glib} parameter.
7584 Both phases are executed after the @code{install} phase.
7587 @defvr {Scheme Variable} guile-build-system
7588 This build system is for Guile packages that consist exclusively of Scheme
7589 code and that are so lean that they don't even have a makefile, let alone a
7590 @file{configure} script. It compiles Scheme code using @command{guild
7591 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
7592 installs the @file{.scm} and @file{.go} files in the right place. It also
7593 installs documentation.
7595 This build system supports cross-compilation by using the
7596 @option{--target} option of @samp{guild compile}.
7598 Packages built with @code{guile-build-system} must provide a Guile package in
7599 their @code{native-inputs} field.
7602 @defvr {Scheme Variable} julia-build-system
7603 This variable is exported by @code{(guix build-system julia)}. It
7604 implements the build procedure used by @uref{https://julialang.org/,
7605 julia} packages, which essentially is similar to running @samp{julia -e
7606 'using Pkg; Pkg.add(package)'} in an environment where
7607 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
7608 Tests are run with @code{Pkg.test}.
7610 Julia packages require the source @code{file-name} to be the real name of the
7611 package, correctly capitalized.
7613 For packages requiring shared library dependencies, you may need to write the
7614 @file{/deps/deps.jl} file manually. It's usually a line of @code{const
7615 variable = /gnu/store/library.so} for each dependency, plus a void function
7616 @code{check_deps() = nothing}.
7618 Some older packages that aren't using @file{Package.toml} yet, will require
7619 this file to be created, too. The function @code{julia-create-package-toml}
7620 helps creating the file. You need to pass the outputs and the source of the
7621 package, it's name (the same as the @code{file-name} parameter), the package
7622 uuid, the package version, and a list of dependencies specified by their name
7626 @defvr {Scheme Variable} maven-build-system
7627 This variable is exported by @code{(guix build-system maven)}. It implements
7628 a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
7629 is a dependency and lifecycle management tool for Java. A user of Maven
7630 specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
7631 When Maven does not have one of the dependencies or plugins in its repository,
7632 it will download them and use them to build the package.
7634 The maven build system ensures that maven will not try to download any
7635 dependency by running in offline mode. Maven will fail if a dependency is
7636 missing. Before running Maven, the @file{pom.xml} (and subprojects) are
7637 modified to specify the version of dependencies and plugins that match the
7638 versions available in the guix build environment. Dependencies and plugins
7639 must be installed in the fake maven repository at @file{lib/m2}, and are
7640 symlinked into a proper repository before maven is run. Maven is instructed
7641 to use that repository for the build and installs built artifacts there.
7642 Changed files are copied to the @file{lib/m2} directory of the package output.
7644 You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
7645 or let the build system use the default @file{pom.xml} file in the sources.
7647 In case you need to specify a dependency's version manually, you can use the
7648 @code{#:local-packages} argument. It takes an association list where the key
7649 is the groupId of the package and its value is an association list where the
7650 key is the artifactId of the package and its value is the version you want to
7651 override in the @file{pom.xml}.
7653 Some packages use dependencies or plugins that are not useful at runtime nor
7654 at build time in Guix. You can alter the @file{pom.xml} file to remove them
7655 using the @code{#:exclude} argument. Its value is an association list where
7656 the key is the groupId of the plugin or dependency you want to remove, and
7657 the value is a list of artifactId you want to remove.
7659 You can override the default @code{jdk} and @code{maven} packages with the
7660 corresponding argument, @code{#:jdk} and @code{#:maven}.
7662 The @code{#:maven-plugins} argument is a list of maven plugins used during
7663 the build, with the same format as the @code{inputs} fields of the package
7664 declaration. Its default value is @code{(default-maven-plugins)} which is
7668 @defvr {Scheme Variable} minify-build-system
7669 This variable is exported by @code{(guix build-system minify)}. It
7670 implements a minification procedure for simple JavaScript packages.
7672 It adds @code{uglify-js} to the set of inputs and uses it to compress
7673 all JavaScript files in the @file{src} directory. A different minifier
7674 package can be specified with the @code{#:uglify-js} parameter, but it
7675 is expected that the package writes the minified code to the standard
7678 When the input JavaScript files are not all located in the @file{src}
7679 directory, the parameter @code{#:javascript-files} can be used to
7680 specify a list of file names to feed to the minifier.
7683 @defvr {Scheme Variable} ocaml-build-system
7684 This variable is exported by @code{(guix build-system ocaml)}. It implements
7685 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
7686 of choosing the correct set of commands to run for each package. OCaml
7687 packages can expect many different commands to be run. This build system will
7690 When the package has a @file{setup.ml} file present at the top-level, it will
7691 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
7692 @code{ocaml setup.ml -install}. The build system will assume that this file
7693 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
7694 care of setting the prefix and enabling tests if they are not disabled. You
7695 can pass configure and build flags with the @code{#:configure-flags} and
7696 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
7697 set of flags used to enable tests. The @code{#:use-make?} key can be used to
7698 bypass this system in the build and install phases.
7700 When the package has a @file{configure} file, it is assumed that it is a
7701 hand-made configure script that requires a different argument format than
7702 in the @code{gnu-build-system}. You can add more flags with the
7703 @code{#:configure-flags} key.
7705 When the package has a @file{Makefile} file (or @code{#:use-make?} is
7706 @code{#t}), it will be used and more flags can be passed to the build and
7707 install phases with the @code{#:make-flags} key.
7709 Finally, some packages do not have these files and use a somewhat standard
7710 location for its build system. In that case, the build system will run
7711 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
7712 providing the path to the required findlib module. Additional flags can
7713 be passed via the @code{#:build-flags} key. Install is taken care of by
7714 @command{opam-installer}. In this case, the @code{opam} package must
7715 be added to the @code{native-inputs} field of the package definition.
7717 Note that most OCaml packages assume they will be installed in the same
7718 directory as OCaml, which is not what we want in guix. In particular, they
7719 will install @file{.so} files in their module's directory, which is usually
7720 fine because it is in the OCaml compiler directory. In guix though, these
7721 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
7722 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
7723 @file{.so} libraries should be installed.
7726 @defvr {Scheme Variable} python-build-system
7727 This variable is exported by @code{(guix build-system python)}. It
7728 implements the more or less standard build procedure used by Python
7729 packages, which consists in running @code{python setup.py build} and
7730 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
7732 For packages that install stand-alone Python programs under @code{bin/},
7733 it takes care of wrapping these programs so that their @env{PYTHONPATH}
7734 environment variable points to all the Python libraries they depend on.
7736 Which Python package is used to perform the build can be specified with
7737 the @code{#:python} parameter. This is a useful way to force a package
7738 to be built for a specific version of the Python interpreter, which
7739 might be necessary if the package is only compatible with a single
7740 interpreter version.
7742 By default guix calls @code{setup.py} under control of
7743 @code{setuptools}, much like @command{pip} does. Some packages are not
7744 compatible with setuptools (and pip), thus you can disable this by
7745 setting the @code{#:use-setuptools?} parameter to @code{#f}.
7748 @defvr {Scheme Variable} perl-build-system
7749 This variable is exported by @code{(guix build-system perl)}. It
7750 implements the standard build procedure for Perl packages, which either
7751 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
7752 followed by @code{Build} and @code{Build install}; or in running
7753 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
7754 @code{make} and @code{make install}, depending on which of
7755 @code{Build.PL} or @code{Makefile.PL} is present in the package
7756 distribution. Preference is given to the former if both @code{Build.PL}
7757 and @code{Makefile.PL} exist in the package distribution. This
7758 preference can be reversed by specifying @code{#t} for the
7759 @code{#:make-maker?} parameter.
7761 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
7762 passes flags specified by the @code{#:make-maker-flags} or
7763 @code{#:module-build-flags} parameter, respectively.
7765 Which Perl package is used can be specified with @code{#:perl}.
7768 @defvr {Scheme Variable} qt-build-system
7769 This variable is exported by @code{(guix build-system qt)}. It
7770 is intended for use with applications using Qt or KDE.
7772 This build system adds the following two phases to the ones defined by
7773 @code{cmake-build-system}:
7777 The phase @code{check-setup} prepares the environment for running
7778 the checks as commonly used by Qt test programs.
7779 For now this only sets some environment variables:
7780 @code{QT_QPA_PLATFORM=offscreen},
7781 @code{DBUS_FATAL_WARNINGS=0} and
7782 @code{CTEST_OUTPUT_ON_FAILURE=1}.
7784 This phase is added before the @code{check} phase.
7785 It's a separate phase to ease adjusting if necessary.
7788 The phase @code{qt-wrap}
7789 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
7790 and output. In case some path is found, all programs in the output's
7791 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
7792 are wrapped in scripts defining the necessary environment variables.
7794 It is possible to exclude specific package outputs from that wrapping process
7795 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
7796 This is useful when an output is known not to contain any Qt binaries, and
7797 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
7800 This phase is added after the @code{install} phase.
7804 @defvr {Scheme Variable} r-build-system
7805 This variable is exported by @code{(guix build-system r)}. It
7806 implements the build procedure used by @uref{https://r-project.org, R}
7807 packages, which essentially is little more than running @samp{R CMD
7808 INSTALL --library=/gnu/store/@dots{}} in an environment where
7809 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
7810 run after installation using the R function
7811 @code{tools::testInstalledPackage}.
7814 @defvr {Scheme Variable} rakudo-build-system
7815 This variable is exported by @code{(guix build-system rakudo)}. It
7816 implements the build procedure used by @uref{https://rakudo.org/,
7817 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
7818 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
7819 installs the binaries, library files and the resources, as well as wrap
7820 the files under the @code{bin/} directory. Tests can be skipped by
7821 passing @code{#f} to the @code{tests?} parameter.
7823 Which rakudo package is used can be specified with @code{rakudo}.
7824 Which perl6-tap-harness package used for the tests can be specified with
7825 @code{#:prove6} or removed by passing @code{#f} to the
7826 @code{with-prove6?} parameter.
7827 Which perl6-zef package used for tests and installing can be specified
7828 with @code{#:zef} or removed by passing @code{#f} to the
7829 @code{with-zef?} parameter.
7832 @defvr {Scheme Variable} texlive-build-system
7833 This variable is exported by @code{(guix build-system texlive)}. It is
7834 used to build TeX packages in batch mode with a specified engine. The
7835 build system sets the @env{TEXINPUTS} variable to find all TeX source
7836 files in the inputs.
7838 By default it runs @code{luatex} on all files ending on @code{ins}. A
7839 different engine and format can be specified with the
7840 @code{#:tex-format} argument. Different build targets can be specified
7841 with the @code{#:build-targets} argument, which expects a list of file
7842 names. The build system adds only @code{texlive-bin} and
7843 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
7844 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
7845 and @code{#:texlive-latex-base}, respectively.
7847 The @code{#:tex-directory} parameter tells the build system where to
7848 install the built files under the texmf tree.
7851 @defvr {Scheme Variable} ruby-build-system
7852 This variable is exported by @code{(guix build-system ruby)}. It
7853 implements the RubyGems build procedure used by Ruby packages, which
7854 involves running @code{gem build} followed by @code{gem install}.
7856 The @code{source} field of a package that uses this build system
7857 typically references a gem archive, since this is the format that Ruby
7858 developers use when releasing their software. The build system unpacks
7859 the gem archive, potentially patches the source, runs the test suite,
7860 repackages the gem, and installs it. Additionally, directories and
7861 tarballs may be referenced to allow building unreleased gems from Git or
7862 a traditional source release tarball.
7864 Which Ruby package is used can be specified with the @code{#:ruby}
7865 parameter. A list of additional flags to be passed to the @command{gem}
7866 command can be specified with the @code{#:gem-flags} parameter.
7869 @defvr {Scheme Variable} waf-build-system
7870 This variable is exported by @code{(guix build-system waf)}. It
7871 implements a build procedure around the @code{waf} script. The common
7872 phases---@code{configure}, @code{build}, and @code{install}---are
7873 implemented by passing their names as arguments to the @code{waf}
7876 The @code{waf} script is executed by the Python interpreter. Which
7877 Python package is used to run the script can be specified with the
7878 @code{#:python} parameter.
7881 @defvr {Scheme Variable} scons-build-system
7882 This variable is exported by @code{(guix build-system scons)}. It
7883 implements the build procedure used by the SCons software construction
7884 tool. This build system runs @code{scons} to build the package,
7885 @code{scons test} to run tests, and then @code{scons install} to install
7888 Additional flags to be passed to @code{scons} can be specified with the
7889 @code{#:scons-flags} parameter. The default build and install targets
7890 can be overridden with @code{#:build-targets} and
7891 @code{#:install-targets} respectively. The version of Python used to
7892 run SCons can be specified by selecting the appropriate SCons package
7893 with the @code{#:scons} parameter.
7896 @defvr {Scheme Variable} haskell-build-system
7897 This variable is exported by @code{(guix build-system haskell)}. It
7898 implements the Cabal build procedure used by Haskell packages, which
7899 involves running @code{runhaskell Setup.hs configure
7900 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
7901 Instead of installing the package by running @code{runhaskell Setup.hs
7902 install}, to avoid trying to register libraries in the read-only
7903 compiler store directory, the build system uses @code{runhaskell
7904 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
7905 addition, the build system generates the package documentation by
7906 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
7907 is passed. Optional Haddock parameters can be passed with the help of
7908 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
7909 not found, the build system looks for @code{Setup.lhs} instead.
7911 Which Haskell compiler is used can be specified with the @code{#:haskell}
7912 parameter which defaults to @code{ghc}.
7915 @defvr {Scheme Variable} dub-build-system
7916 This variable is exported by @code{(guix build-system dub)}. It
7917 implements the Dub build procedure used by D packages, which
7918 involves running @code{dub build} and @code{dub run}.
7919 Installation is done by copying the files manually.
7921 Which D compiler is used can be specified with the @code{#:ldc}
7922 parameter which defaults to @code{ldc}.
7925 @defvr {Scheme Variable} emacs-build-system
7926 This variable is exported by @code{(guix build-system emacs)}. It
7927 implements an installation procedure similar to the packaging system
7928 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
7930 It first creates the @code{@code{package}-autoloads.el} file, then it
7931 byte compiles all Emacs Lisp files. Differently from the Emacs
7932 packaging system, the Info documentation files are moved to the standard
7933 documentation directory and the @file{dir} file is deleted. The Elisp
7934 package files are installed directly under @file{share/emacs/site-lisp}.
7937 @defvr {Scheme Variable} font-build-system
7938 This variable is exported by @code{(guix build-system font)}. It
7939 implements an installation procedure for font packages where upstream
7940 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
7941 need to be copied into place. It copies font files to standard
7942 locations in the output directory.
7945 @defvr {Scheme Variable} meson-build-system
7946 This variable is exported by @code{(guix build-system meson)}. It
7947 implements the build procedure for packages that use
7948 @url{https://mesonbuild.com, Meson} as their build system.
7950 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
7951 of inputs, and they can be changed with the parameters @code{#:meson}
7952 and @code{#:ninja} if needed. The default Meson is
7953 @code{meson-for-build}, which is special because it doesn't clear the
7954 @code{RUNPATH} of binaries and libraries when they are installed.
7956 This build system is an extension of @code{gnu-build-system}, but with the
7957 following phases changed to some specific for Meson:
7962 The phase runs @code{meson} with the flags specified in
7963 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
7964 @code{debugoptimized} unless something else is specified in
7965 @code{#:build-type}.
7968 The phase runs @code{ninja} to build the package in parallel by default, but
7969 this can be changed with @code{#:parallel-build?}.
7972 The phase runs @code{ninja} with the target specified in @code{#:test-target},
7973 which is @code{"test"} by default.
7976 The phase runs @code{ninja install} and can not be changed.
7979 Apart from that, the build system also adds the following phases:
7984 This phase ensures that all binaries can find the libraries they need.
7985 It searches for required libraries in subdirectories of the package being
7986 built, and adds those to @code{RUNPATH} where needed. It also removes
7987 references to libraries left over from the build phase by
7988 @code{meson-for-build}, such as test dependencies, that aren't actually
7989 required for the program to run.
7991 @item glib-or-gtk-wrap
7992 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
7993 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
7995 @item glib-or-gtk-compile-schemas
7996 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
7997 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
8001 @defvr {Scheme Variable} linux-module-build-system
8002 @code{linux-module-build-system} allows building Linux kernel modules.
8004 @cindex build phases
8005 This build system is an extension of @code{gnu-build-system}, but with the
8006 following phases changed:
8011 This phase configures the environment so that the Linux kernel's Makefile
8012 can be used to build the external kernel module.
8015 This phase uses the Linux kernel's Makefile in order to build the external
8019 This phase uses the Linux kernel's Makefile in order to install the external
8023 It is possible and useful to specify the Linux kernel to use for building
8024 the module (in the @code{arguments} form of a package using the
8025 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
8028 @defvr {Scheme Variable} node-build-system
8029 This variable is exported by @code{(guix build-system node)}. It
8030 implements the build procedure used by @uref{https://nodejs.org,
8031 Node.js}, which implements an approximation of the @code{npm install}
8032 command, followed by an @code{npm test} command.
8034 Which Node.js package is used to interpret the @code{npm} commands can
8035 be specified with the @code{#:node} parameter which defaults to
8039 Lastly, for packages that do not need anything as sophisticated, a
8040 ``trivial'' build system is provided. It is trivial in the sense that
8041 it provides basically no support: it does not pull any implicit inputs,
8042 and does not have a notion of build phases.
8044 @defvr {Scheme Variable} trivial-build-system
8045 This variable is exported by @code{(guix build-system trivial)}.
8047 This build system requires a @code{#:builder} argument. This argument
8048 must be a Scheme expression that builds the package output(s)---as
8049 with @code{build-expression->derivation} (@pxref{Derivations,
8050 @code{build-expression->derivation}}).
8054 @section Build Phases
8056 @cindex build phases, for packages
8057 Almost all package build systems implement a notion @dfn{build phases}:
8058 a sequence of actions that the build system executes, when you build the
8059 package, leading to the installed byproducts in the store. A notable
8060 exception is the ``bare-bones'' @code{trivial-build-system}
8061 (@pxref{Build Systems}).
8063 As discussed in the previous section, those build systems provide a
8064 standard list of phases. For @code{gnu-build-system}, the standard
8065 phases include an @code{unpack} phase to unpack the source code tarball,
8066 a @command{configure} phase to run @code{./configure}, a @code{build}
8067 phase to run @command{make}, and (among others) an @code{install} phase
8068 to run @command{make install}; @pxref{Build Systems}, for a more
8069 detailed view of these phases. Likewise, @code{cmake-build-system}
8070 inherits these phases, but its @code{configure} phase runs
8071 @command{cmake} instead of @command{./configure}. Other build systems,
8072 such as @code{python-build-system}, have a wholly different list of
8073 standard phases. All this code runs on the @dfn{build side}: it is
8074 evaluated when you actually build the package, in a dedicated build
8075 process spawned by the build daemon (@pxref{Invoking guix-daemon}).
8077 Build phases are represented as association lists or ``alists''
8078 (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
8079 each key is a symbol for the name of the phase and the associated value
8080 is a procedure that accepts an arbitrary number of arguments. By
8081 convention, those procedures receive information about the build in the
8082 form of @dfn{keyword parameters}, which they can use or ignore.
8084 For example, here is how @code{(guix build gnu-build-system)} defines
8085 @code{%standard-phases}, the variable holding its alist of build
8086 phases@footnote{We present a simplified view of those build phases, but
8087 do take a look at @code{(guix build gnu-build-system)} to see all the
8091 ;; The build phases of 'gnu-build-system'.
8093 (define* (unpack #:key source #:allow-other-keys)
8094 ;; Extract the source tarball.
8095 (invoke "tar" "xvf" source))
8097 (define* (configure #:key outputs #:allow-other-keys)
8098 ;; Run the 'configure' script. Install to output "out".
8099 (let ((out (assoc-ref outputs "out")))
8100 (invoke "./configure"
8101 (string-append "--prefix=" out))))
8103 (define* (build #:allow-other-keys)
8107 (define* (check #:key (test-target "check") (tests? #true)
8109 ;; Run the test suite.
8111 (invoke "make" test-target)
8112 (display "test suite not run\n")))
8114 (define* (install #:allow-other-keys)
8115 ;; Install files to the prefix 'configure' specified.
8116 (invoke "make" "install"))
8118 (define %standard-phases
8119 ;; The list of standard phases (quite a few are omitted
8120 ;; for brevity). Each element is a symbol/procedure pair.
8121 (list (cons 'unpack unpack)
8122 (cons 'configure configure)
8125 (cons 'install install)))
8128 This shows how @code{%standard-phases} is defined as a list of
8129 symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
8130 Manual}). The first pair associates the @code{unpack} procedure with
8131 the @code{unpack} symbol---a name; the second pair defines the
8132 @code{configure} phase similarly, and so on. When building a package
8133 that uses @code{gnu-build-system} with its default list of phases, those
8134 phases are executed sequentially. You can see the name of each phase
8135 started and completed in the build log of packages that you build.
8137 Let's now look at the procedures themselves. Each one is defined with
8138 @code{define*}: @code{#:key} lists keyword parameters the procedure
8139 accepts, possibly with a default value, and @code{#:allow-other-keys}
8140 specifies that other keyword parameters are ignored (@pxref{Optional
8141 Arguments,,, guile, GNU Guile Reference Manual}).
8143 The @code{unpack} procedure honors the @code{source} parameter, which
8144 the build system uses to pass the file name of the source tarball (or
8145 version control checkout), and it ignores other parameters. The
8146 @code{configure} phase only cares about the @code{outputs} parameter, an
8147 alist mapping package output names to their store file name
8148 (@pxref{Packages with Multiple Outputs}). It extracts the file name of
8149 for @code{out}, the default output, and passes it to
8150 @command{./configure} as the installation prefix, meaning that
8151 @command{make install} will eventually copy all the files in that
8152 directory (@pxref{Configuration, configuration and makefile
8153 conventions,, standards, GNU Coding Standards}). @code{build} and
8154 @code{install} ignore all their arguments. @code{check} honors the
8155 @code{test-target} argument, which specifies the name of the Makefile
8156 target to run tests; it prints a message and skips tests when
8157 @code{tests?} is false.
8159 @cindex build phases, customizing
8160 The list of phases used for a particular package can be changed with the
8161 @code{#:phases} parameter of the build system. Changing the set of
8162 build phases boils down to building a new alist of phases based on the
8163 @code{%standard-phases} alist described above. This can be done with
8164 standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
8165 Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
8166 more convenient to do so with @code{modify-phases} (@pxref{Build
8167 Utilities, @code{modify-phases}}).
8169 Here is an example of a package definition that removes the
8170 @code{configure} phase of @code{%standard-phases} and inserts a new
8171 phase before the @code{build} phase, called
8172 @code{set-prefix-in-makefile}:
8175 (define-public example
8178 ;; other fields omitted
8179 (build-system gnu-build-system)
8181 '(#:phases (modify-phases %standard-phases
8183 (add-before 'build 'set-prefix-in-makefile
8184 (lambda* (#:key outputs #:allow-other-keys)
8185 ;; Modify the makefile so that its
8186 ;; 'PREFIX' variable points to "out".
8187 (let ((out (assoc-ref outputs "out")))
8188 (substitute* "Makefile"
8190 (string-append "PREFIX = "
8195 The new phase that is inserted is written as an anonymous procedure,
8196 introduced with @code{lambda*}; it honors the @code{outputs} parameter
8197 we have seen before. @xref{Build Utilities}, for more about the helpers
8198 used by this phase, and for more examples of @code{modify-phases}.
8200 @cindex code staging
8201 @cindex staging, of code
8202 Keep in mind that build phases are code evaluated at the time the
8203 package is actually built. This explains why the whole
8204 @code{modify-phases} expression above is quoted (it comes after the
8205 @code{'} or apostrophe): it is @dfn{staged} for later execution.
8206 @xref{G-Expressions}, for an explanation of code staging and the
8207 @dfn{code strata} involved.
8209 @node Build Utilities
8210 @section Build Utilities
8212 As soon as you start writing non-trivial package definitions
8213 (@pxref{Defining Packages}) or other build actions
8214 (@pxref{G-Expressions}), you will likely start looking for helpers for
8215 ``shell-like'' actions---creating directories, copying and deleting
8216 files recursively, manipulating build phases, and so on. The
8217 @code{(guix build utils)} module provides such utility procedures.
8219 Most build systems load @code{(guix build utils)} (@pxref{Build
8220 Systems}). Thus, when writing custom build phases for your package
8221 definitions, you can usually assume those procedures are in scope.
8223 When writing G-expressions, you can import @code{(guix build utils)} on
8224 the ``build side'' using @code{with-imported-modules} and then put it in
8225 scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
8226 guile, GNU Guile Reference Manual}):
8229 (with-imported-modules '((guix build utils)) ;import it
8230 (computed-file "empty-tree"
8233 (use-modules (guix build utils))
8235 ;; Happily use its 'mkdir-p' procedure.
8236 (mkdir-p (string-append #$output "/a/b/c")))))
8239 The remainder of this section is the reference for most of the utility
8240 procedures provided by @code{(guix build utils)}.
8242 @c TODO Document what's missing.
8244 @subsection Dealing with Store File Names
8246 This section documents procedures that deal with store file names.
8248 @deffn {Scheme Procedure} %store-directory
8249 Return the directory name of the store.
8252 @deffn {Scheme Procedure} store-file-name? @var{file}
8253 Return true if @var{file} is in the store.
8256 @deffn {Scheme Procedure} strip-store-file-name @var{file}
8257 Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
8258 The result is typically a @code{"@var{package}-@var{version}"} string.
8261 @deffn {Scheme Procedure} package-name->name+version @var{name}
8262 Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
8263 values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
8264 unavailable, @var{name} and @code{#f} are returned. The first hyphen
8265 followed by a digit is considered to introduce the version part.
8268 @subsection File Types
8270 The procedures below deal with files and file types.
8272 @deffn {Scheme Procedure} directory-exists? @var{dir}
8273 Return @code{#t} if @var{dir} exists and is a directory.
8276 @deffn {Scheme Procedure} executable-file? @var{file}
8277 Return @code{#t} if @var{file} exists and is executable.
8280 @deffn {Scheme Procedure} symbolic-link? @var{file}
8281 Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
8284 @deffn {Scheme Procedure} elf-file? @var{file}
8285 @deffnx {Scheme Procedure} ar-file? @var{file}
8286 @deffnx {Scheme Procedure} gzip-file? @var{file}
8287 Return @code{#t} if @var{file} is, respectively, an ELF file, an
8288 @code{ar} archive (such as a @file{.a} static library), or a gzip file.
8291 @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
8292 If @var{file} is a gzip file, reset its embedded timestamp (as with
8293 @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
8294 When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
8297 @subsection File Manipulation
8299 The following procedures and macros help create, modify, and delete
8300 files. They provide functionality comparable to common shell utilities
8301 such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
8302 @command{sed}. They complement Guile's extensive, but low-level, file
8303 system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
8305 @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
8306 Run @var{body} with @var{directory} as the process's current directory.
8308 Essentially, this macro changes the current directory to @var{directory}
8309 before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
8310 guile, GNU Guile Reference Manual}). It changes back to the initial
8311 directory when the dynamic extent of @var{body} is left, be it @i{via}
8312 normal procedure return or @i{via} a non-local exit such as an
8316 @deffn {Scheme Procedure} mkdir-p @var{dir}
8317 Create directory @var{dir} and all its ancestors.
8320 @deffn {Scheme Procedure} install-file @var{file} @var{directory}
8321 Create @var{directory} if it does not exist and copy @var{file} in there
8322 under the same name.
8325 @deffn {Scheme Procedure} make-file-writable @var{file}
8326 Make @var{file} writable for its owner.
8329 @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
8330 [#:log (current-output-port)] [#:follow-symlinks? #f] [#:keep-mtime? #f]
8331 Copy @var{source} directory to @var{destination}. Follow symlinks if
8332 @var{follow-symlinks?} is true; otherwise, just preserve them. When
8333 @var{keep-mtime?} is true, keep the modification time of the files in
8334 @var{source} on those of @var{destination}. Write verbose output to the
8338 @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
8339 [#:follow-mounts? #f]
8340 Delete @var{dir} recursively, like @command{rm -rf}, without following
8341 symlinks. Don't follow mount points either, unless @var{follow-mounts?}
8342 is true. Report but ignore errors.
8345 @deffn {Scheme Syntax} substitute* @var{file} @
8346 ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
8347 Substitute @var{regexp} in @var{file} by the string returned by
8348 @var{body}. @var{body} is evaluated with each @var{match-var} bound to
8349 the corresponding positional regexp sub-expression. For example:
8355 (("foo([a-z]+)bar(.*)$" all letters end)
8356 (string-append "baz" letter end)))
8359 Here, anytime a line of @var{file} contains @code{hello}, it is replaced
8360 by @code{good morning}. Anytime a line of @var{file} matches the second
8361 regexp, @code{all} is bound to the complete match, @code{letters} is bound
8362 to the first sub-expression, and @code{end} is bound to the last one.
8364 When one of the @var{match-var} is @code{_}, no variable is bound to the
8365 corresponding match substring.
8367 Alternatively, @var{file} may be a list of file names, in which case
8368 they are all subject to the substitutions.
8370 Be careful about using @code{$} to match the end of a line; by itself it
8371 won't match the terminating newline of a line.
8374 @subsection File Search
8376 @cindex file, searching
8377 This section documents procedures to search and filter files.
8379 @deffn {Scheme Procedure} file-name-predicate @var{regexp}
8380 Return a predicate that returns true when passed a file name whose base
8381 name matches @var{regexp}.
8384 @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
8385 [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
8386 Return the lexicographically sorted list of files under @var{dir} for
8387 which @var{pred} returns true. @var{pred} is passed two arguments: the
8388 absolute file name, and its stat buffer; the default predicate always
8389 returns true. @var{pred} can also be a regular expression, in which
8390 case it is equivalent to @code{(file-name-predicate @var{pred})}.
8391 @var{stat} is used to obtain file information; using @code{lstat} means
8392 that symlinks are not followed. If @var{directories?} is true, then
8393 directories will also be included. If @var{fail-on-error?} is true,
8394 raise an exception upon error.
8397 Here are a few examples where we assume that the current directory is
8398 the root of the Guix source tree:
8401 ;; List all the regular files in the current directory.
8403 @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
8405 ;; List all the .scm files under gnu/services.
8406 (find-files "gnu/services" "\\.scm$")
8407 @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
8409 ;; List ar files in the current directory.
8410 (find-files "." (lambda (file stat) (ar-file? file)))
8411 @result{} ("./libformat.a" "./libstore.a" @dots{})
8414 @deffn {Scheme Procedure} which @var{program}
8415 Return the complete file name for @var{program} as found in
8416 @code{$PATH}, or @code{#f} if @var{program} could not be found.
8419 @subsection Build Phases
8421 @cindex build phases
8422 The @code{(guix build utils)} also contains tools to manipulate build
8423 phases as used by build systems (@pxref{Build Systems}). Build phases
8424 are represented as association lists or ``alists'' (@pxref{Association
8425 Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
8426 naming the phase and the associated value is a procedure (@pxref{Build
8429 Guile core and the @code{(srfi srfi-1)} module both provide tools to
8430 manipulate alists. The @code{(guix build utils)} module complements
8431 those with tools written with build phases in mind.
8433 @cindex build phases, modifying
8434 @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
8435 Modify @var{phases} sequentially as per each @var{clause}, which may
8436 have one of the following forms:
8439 (delete @var{old-phase-name})
8440 (replace @var{old-phase-name} @var{new-phase})
8441 (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
8442 (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
8445 Where every @var{phase-name} above is an expression evaluating to a
8446 symbol, and @var{new-phase} an expression evaluating to a procedure.
8449 The example below is taken from the definition of the @code{grep}
8450 package. It adds a phase to run after the @code{install} phase, called
8451 @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
8452 is for anonymous procedures) that takes a @code{#:outputs} keyword
8453 argument and ignores extra keyword arguments (@pxref{Optional
8454 Arguments,,, guile, GNU Guile Reference Manual}, for more on
8455 @code{lambda*} and optional and keyword arguments.) The phase uses
8456 @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
8457 scripts so that they refer to @code{grep} by its absolute file name:
8460 (modify-phases %standard-phases
8461 (add-after 'install 'fix-egrep-and-fgrep
8462 ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
8463 ;; absolute file name instead of searching for it in $PATH.
8464 (lambda* (#:key outputs #:allow-other-keys)
8465 (let* ((out (assoc-ref outputs "out"))
8466 (bin (string-append out "/bin")))
8467 (substitute* (list (string-append bin "/egrep")
8468 (string-append bin "/fgrep"))
8470 (string-append "exec " bin "/grep")))
8474 In the example below, phases are modified in two ways: the standard
8475 @code{configure} phase is deleted, presumably because the package does
8476 not have a @file{configure} script or anything similar, and the default
8477 @code{install} phase is replaced by one that manually copies the
8478 executable files to be installed:
8481 (modify-phases %standard-phases
8482 (delete 'configure) ;no 'configure' script
8484 (lambda* (#:key outputs #:allow-other-keys)
8485 ;; The package's Makefile doesn't provide an "install"
8486 ;; rule so do it by ourselves.
8487 (let ((bin (string-append (assoc-ref outputs "out")
8489 (install-file "footswitch" bin)
8490 (install-file "scythe" bin)
8494 @c TODO: Add more examples.
8503 Conceptually, the @dfn{store} is the place where derivations that have
8504 been built successfully are stored---by default, @file{/gnu/store}.
8505 Sub-directories in the store are referred to as @dfn{store items} or
8506 sometimes @dfn{store paths}. The store has an associated database that
8507 contains information such as the store paths referred to by each store
8508 path, and the list of @emph{valid} store items---results of successful
8509 builds. This database resides in @file{@var{localstatedir}/guix/db},
8510 where @var{localstatedir} is the state directory specified @i{via}
8511 @option{--localstatedir} at configure time, usually @file{/var}.
8513 The store is @emph{always} accessed by the daemon on behalf of its clients
8514 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
8515 connect to the daemon over a Unix-domain socket, send requests to it,
8516 and read the result---these are remote procedure calls, or RPCs.
8519 Users must @emph{never} modify files under @file{/gnu/store} directly.
8520 This would lead to inconsistencies and break the immutability
8521 assumptions of Guix's functional model (@pxref{Introduction}).
8523 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
8524 how to check the integrity of the store and attempt recovery from
8525 accidental modifications.
8528 The @code{(guix store)} module provides procedures to connect to the
8529 daemon, and to perform RPCs. These are described below. By default,
8530 @code{open-connection}, and thus all the @command{guix} commands,
8531 connect to the local daemon or to the URI specified by the
8532 @env{GUIX_DAEMON_SOCKET} environment variable.
8534 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
8535 When set, the value of this variable should be a file name or a URI
8536 designating the daemon endpoint. When it is a file name, it denotes a
8537 Unix-domain socket to connect to. In addition to file names, the
8538 supported URI schemes are:
8543 These are for Unix-domain sockets.
8544 @code{file:///var/guix/daemon-socket/socket} is equivalent to
8545 @file{/var/guix/daemon-socket/socket}.
8548 @cindex daemon, remote access
8549 @cindex remote access to the daemon
8550 @cindex daemon, cluster setup
8551 @cindex clusters, daemon setup
8552 These URIs denote connections over TCP/IP, without encryption nor
8553 authentication of the remote host. The URI must specify the host name
8554 and optionally a port number (by default port 44146 is used):
8557 guix://master.guix.example.org:1234
8560 This setup is suitable on local networks, such as clusters, where only
8561 trusted nodes may connect to the build daemon at
8562 @code{master.guix.example.org}.
8564 The @option{--listen} option of @command{guix-daemon} can be used to
8565 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
8566 @option{--listen}}).
8569 @cindex SSH access to build daemons
8570 These URIs allow you to connect to a remote daemon over SSH. This
8571 feature requires Guile-SSH (@pxref{Requirements}) and a working
8572 @command{guile} binary in @env{PATH} on the destination machine. It
8573 supports public key and GSSAPI authentication. A typical URL might look
8577 ssh://charlie@@guix.example.org:22
8580 As for @command{guix copy}, the usual OpenSSH client configuration files
8581 are honored (@pxref{Invoking guix copy}).
8584 Additional URI schemes may be supported in the future.
8586 @c XXX: Remove this note when the protocol incurs fewer round trips
8587 @c and when (guix derivations) no longer relies on file system access.
8589 The ability to connect to remote build daemons is considered
8590 experimental as of @value{VERSION}. Please get in touch with us to
8591 share any problems or suggestions you may have (@pxref{Contributing}).
8595 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
8596 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
8597 @var{reserve-space?} is true, instruct it to reserve a little bit of
8598 extra space on the file system so that the garbage collector can still
8599 operate should the disk become full. Return a server object.
8601 @var{file} defaults to @code{%default-socket-path}, which is the normal
8602 location given the options that were passed to @command{configure}.
8605 @deffn {Scheme Procedure} close-connection @var{server}
8606 Close the connection to @var{server}.
8609 @defvr {Scheme Variable} current-build-output-port
8610 This variable is bound to a SRFI-39 parameter, which refers to the port
8611 where build and error logs sent by the daemon should be written.
8614 Procedures that make RPCs all take a server object as their first
8617 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
8618 @cindex invalid store items
8619 Return @code{#t} when @var{path} designates a valid store item and
8620 @code{#f} otherwise (an invalid item may exist on disk but still be
8621 invalid, for instance because it is the result of an aborted or failed
8624 A @code{&store-protocol-error} condition is raised if @var{path} is not
8625 prefixed by the store directory (@file{/gnu/store}).
8628 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
8629 Add @var{text} under file @var{name} in the store, and return its store
8630 path. @var{references} is the list of store paths referred to by the
8631 resulting store path.
8634 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
8636 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
8637 file names, or derivation/output pairs, using the specified
8638 @var{mode}---@code{(build-mode normal)} by default.
8641 Note that the @code{(guix monads)} module provides a monad as well as
8642 monadic versions of the above procedures, with the goal of making it
8643 more convenient to work with code that accesses the store (@pxref{The
8647 @i{This section is currently incomplete.}
8650 @section Derivations
8653 Low-level build actions and the environment in which they are performed
8654 are represented by @dfn{derivations}. A derivation contains the
8655 following pieces of information:
8659 The outputs of the derivation---derivations produce at least one file or
8660 directory in the store, but may produce more.
8663 @cindex build-time dependencies
8664 @cindex dependencies, build-time
8665 The inputs of the derivations---i.e., its build-time dependencies---which may
8666 be other derivations or plain files in the store (patches, build scripts,
8670 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
8673 The file name of a build script in the store, along with the arguments
8677 A list of environment variables to be defined.
8681 @cindex derivation path
8682 Derivations allow clients of the daemon to communicate build actions to
8683 the store. They exist in two forms: as an in-memory representation,
8684 both on the client- and daemon-side, and as files in the store whose
8685 name end in @file{.drv}---these files are referred to as @dfn{derivation
8686 paths}. Derivations paths can be passed to the @code{build-derivations}
8687 procedure to perform the build actions they prescribe (@pxref{The
8690 @cindex fixed-output derivations
8691 Operations such as file downloads and version-control checkouts for
8692 which the expected content hash is known in advance are modeled as
8693 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
8694 of a fixed-output derivation are independent of its inputs---e.g., a
8695 source code download produces the same result regardless of the download
8696 method and tools being used.
8699 @cindex run-time dependencies
8700 @cindex dependencies, run-time
8701 The outputs of derivations---i.e., the build results---have a set of
8702 @dfn{references}, as reported by the @code{references} RPC or the
8703 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
8704 are the set of run-time dependencies of the build results. References are a
8705 subset of the inputs of the derivation; this subset is automatically computed
8706 by the build daemon by scanning all the files in the outputs.
8708 The @code{(guix derivations)} module provides a representation of
8709 derivations as Scheme objects, along with procedures to create and
8710 otherwise manipulate derivations. The lowest-level primitive to create
8711 a derivation is the @code{derivation} procedure:
8713 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
8714 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
8715 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
8716 [#:system (%current-system)] [#:references-graphs #f] @
8717 [#:allowed-references #f] [#:disallowed-references #f] @
8718 [#:leaked-env-vars #f] [#:local-build? #f] @
8719 [#:substitutable? #t] [#:properties '()]
8720 Build a derivation with the given arguments, and return the resulting
8721 @code{<derivation>} object.
8723 When @var{hash} and @var{hash-algo} are given, a
8724 @dfn{fixed-output derivation} is created---i.e., one whose result is
8725 known in advance, such as a file download. If, in addition,
8726 @var{recursive?} is true, then that fixed output may be an executable
8727 file or a directory and @var{hash} must be the hash of an archive
8728 containing this output.
8730 When @var{references-graphs} is true, it must be a list of file
8731 name/store path pairs. In that case, the reference graph of each store
8732 path is exported in the build environment in the corresponding file, in
8733 a simple text format.
8735 When @var{allowed-references} is true, it must be a list of store items
8736 or outputs that the derivation's output may refer to. Likewise,
8737 @var{disallowed-references}, if true, must be a list of things the
8738 outputs may @emph{not} refer to.
8740 When @var{leaked-env-vars} is true, it must be a list of strings
8741 denoting environment variables that are allowed to ``leak'' from the
8742 daemon's environment to the build environment. This is only applicable
8743 to fixed-output derivations---i.e., when @var{hash} is true. The main
8744 use is to allow variables such as @code{http_proxy} to be passed to
8745 derivations that download files.
8747 When @var{local-build?} is true, declare that the derivation is not a
8748 good candidate for offloading and should rather be built locally
8749 (@pxref{Daemon Offload Setup}). This is the case for small derivations
8750 where the costs of data transfers would outweigh the benefits.
8752 When @var{substitutable?} is false, declare that substitutes of the
8753 derivation's output should not be used (@pxref{Substitutes}). This is
8754 useful, for instance, when building packages that capture details of the
8755 host CPU instruction set.
8757 @var{properties} must be an association list describing ``properties'' of the
8758 derivation. It is kept as-is, uninterpreted, in the derivation.
8762 Here's an example with a shell script as its builder, assuming
8763 @var{store} is an open connection to the daemon, and @var{bash} points
8764 to a Bash executable in the store:
8767 (use-modules (guix utils)
8771 (let ((builder ; add the Bash script to the store
8772 (add-text-to-store store "my-builder.sh"
8773 "echo hello world > $out\n" '())))
8774 (derivation store "foo"
8775 bash `("-e" ,builder)
8776 #:inputs `((,bash) (,builder))
8777 #:env-vars '(("HOME" . "/homeless"))))
8778 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
8781 As can be guessed, this primitive is cumbersome to use directly. A
8782 better approach is to write build scripts in Scheme, of course! The
8783 best course of action for that is to write the build code as a
8784 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
8785 information, @pxref{G-Expressions}.
8787 Once upon a time, @code{gexp->derivation} did not exist and constructing
8788 derivations with build code written in Scheme was achieved with
8789 @code{build-expression->derivation}, documented below. This procedure
8790 is now deprecated in favor of the much nicer @code{gexp->derivation}.
8792 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
8793 @var{name} @var{exp} @
8794 [#:system (%current-system)] [#:inputs '()] @
8795 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
8796 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
8797 [#:references-graphs #f] [#:allowed-references #f] @
8798 [#:disallowed-references #f] @
8799 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
8800 Return a derivation that executes Scheme expression @var{exp} as a
8801 builder for derivation @var{name}. @var{inputs} must be a list of
8802 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
8803 @code{"out"} is assumed. @var{modules} is a list of names of Guile
8804 modules from the current search path to be copied in the store,
8805 compiled, and made available in the load path during the execution of
8806 @var{exp}---e.g., @code{((guix build utils) (guix build
8807 gnu-build-system))}.
8809 @var{exp} is evaluated in an environment where @code{%outputs} is bound
8810 to a list of output/path pairs, and where @code{%build-inputs} is bound
8811 to a list of string/output-path pairs made from @var{inputs}.
8812 Optionally, @var{env-vars} is a list of string pairs specifying the name
8813 and value of environment variables visible to the builder. The builder
8814 terminates by passing the result of @var{exp} to @code{exit}; thus, when
8815 @var{exp} returns @code{#f}, the build is considered to have failed.
8817 @var{exp} is built using @var{guile-for-build} (a derivation). When
8818 @var{guile-for-build} is omitted or is @code{#f}, the value of the
8819 @code{%guile-for-build} fluid is used instead.
8821 See the @code{derivation} procedure for the meaning of
8822 @var{references-graphs}, @var{allowed-references},
8823 @var{disallowed-references}, @var{local-build?}, and
8824 @var{substitutable?}.
8828 Here's an example of a single-output derivation that creates a directory
8829 containing one file:
8832 (let ((builder '(let ((out (assoc-ref %outputs "out")))
8833 (mkdir out) ; create /gnu/store/@dots{}-goo
8834 (call-with-output-file (string-append out "/test")
8836 (display '(hello guix) p))))))
8837 (build-expression->derivation store "goo" builder))
8839 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
8843 @node The Store Monad
8844 @section The Store Monad
8848 The procedures that operate on the store described in the previous
8849 sections all take an open connection to the build daemon as their first
8850 argument. Although the underlying model is functional, they either have
8851 side effects or depend on the current state of the store.
8853 The former is inconvenient: the connection to the build daemon has to be
8854 carried around in all those functions, making it impossible to compose
8855 functions that do not take that parameter with functions that do. The
8856 latter can be problematic: since store operations have side effects
8857 and/or depend on external state, they have to be properly sequenced.
8859 @cindex monadic values
8860 @cindex monadic functions
8861 This is where the @code{(guix monads)} module comes in. This module
8862 provides a framework for working with @dfn{monads}, and a particularly
8863 useful monad for our uses, the @dfn{store monad}. Monads are a
8864 construct that allows two things: associating ``context'' with values
8865 (in our case, the context is the store), and building sequences of
8866 computations (here computations include accesses to the store). Values
8867 in a monad---values that carry this additional context---are called
8868 @dfn{monadic values}; procedures that return such values are called
8869 @dfn{monadic procedures}.
8871 Consider this ``normal'' procedure:
8874 (define (sh-symlink store)
8875 ;; Return a derivation that symlinks the 'bash' executable.
8876 (let* ((drv (package-derivation store bash))
8877 (out (derivation->output-path drv))
8878 (sh (string-append out "/bin/bash")))
8879 (build-expression->derivation store "sh"
8880 `(symlink ,sh %output))))
8883 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
8884 as a monadic function:
8887 (define (sh-symlink)
8888 ;; Same, but return a monadic value.
8889 (mlet %store-monad ((drv (package->derivation bash)))
8890 (gexp->derivation "sh"
8891 #~(symlink (string-append #$drv "/bin/bash")
8895 There are several things to note in the second version: the @code{store}
8896 parameter is now implicit and is ``threaded'' in the calls to the
8897 @code{package->derivation} and @code{gexp->derivation} monadic
8898 procedures, and the monadic value returned by @code{package->derivation}
8899 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
8901 As it turns out, the call to @code{package->derivation} can even be
8902 omitted since it will take place implicitly, as we will see later
8903 (@pxref{G-Expressions}):
8906 (define (sh-symlink)
8907 (gexp->derivation "sh"
8908 #~(symlink (string-append #$bash "/bin/bash")
8913 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
8914 @c for the funny quote.
8915 Calling the monadic @code{sh-symlink} has no effect. As someone once
8916 said, ``you exit a monad like you exit a building on fire: by running''.
8917 So, to exit the monad and get the desired effect, one must use
8918 @code{run-with-store}:
8921 (run-with-store (open-connection) (sh-symlink))
8922 @result{} /gnu/store/...-sh-symlink
8925 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
8926 new ``meta-commands'' to make it easier to deal with monadic procedures:
8927 @code{run-in-store}, and @code{enter-store-monad}. The former is used
8928 to ``run'' a single monadic value through the store:
8931 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
8932 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
8935 The latter enters a recursive REPL, where all the return values are
8936 automatically run through the store:
8939 scheme@@(guile-user)> ,enter-store-monad
8940 store-monad@@(guile-user) [1]> (package->derivation hello)
8941 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
8942 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
8943 $3 = "/gnu/store/@dots{}-foo"
8944 store-monad@@(guile-user) [1]> ,q
8945 scheme@@(guile-user)>
8949 Note that non-monadic values cannot be returned in the
8950 @code{store-monad} REPL.
8952 The main syntactic forms to deal with monads in general are provided by
8953 the @code{(guix monads)} module and are described below.
8955 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
8956 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
8960 @deffn {Scheme Syntax} return @var{val}
8961 Return a monadic value that encapsulates @var{val}.
8964 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
8965 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
8966 procedures @var{mproc}@dots{}@footnote{This operation is commonly
8967 referred to as ``bind'', but that name denotes an unrelated procedure in
8968 Guile. Thus we use this somewhat cryptic symbol inherited from the
8969 Haskell language.}. There can be one @var{mproc} or several of them, as
8974 (with-monad %state-monad
8976 (lambda (x) (return (+ 1 x)))
8977 (lambda (x) (return (* 2 x)))))
8981 @result{} some-state
8985 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
8987 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
8989 Bind the variables @var{var} to the monadic values @var{mval} in
8990 @var{body}, which is a sequence of expressions. As with the bind
8991 operator, this can be thought of as ``unpacking'' the raw, non-monadic
8992 value ``contained'' in @var{mval} and making @var{var} refer to that
8993 raw, non-monadic value within the scope of the @var{body}. The form
8994 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
8995 @var{val}, as per @code{let}. The binding operations occur in sequence
8996 from left to right. The last expression of @var{body} must be a monadic
8997 expression, and its result will become the result of the @code{mlet} or
8998 @code{mlet*} when run in the @var{monad}.
9000 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
9001 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
9004 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
9005 Bind @var{mexp} and the following monadic expressions in sequence,
9006 returning the result of the last expression. Every expression in the
9007 sequence must be a monadic expression.
9009 This is akin to @code{mlet}, except that the return values of the
9010 monadic expressions are ignored. In that sense, it is analogous to
9011 @code{begin}, but applied to monadic expressions.
9014 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
9015 When @var{condition} is true, evaluate the sequence of monadic
9016 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
9017 @var{condition} is false, return @code{*unspecified*} in the current
9018 monad. Every expression in the sequence must be a monadic expression.
9021 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
9022 When @var{condition} is false, evaluate the sequence of monadic
9023 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
9024 @var{condition} is true, return @code{*unspecified*} in the current
9025 monad. Every expression in the sequence must be a monadic expression.
9029 The @code{(guix monads)} module provides the @dfn{state monad}, which
9030 allows an additional value---the state---to be @emph{threaded} through
9031 monadic procedure calls.
9033 @defvr {Scheme Variable} %state-monad
9034 The state monad. Procedures in the state monad can access and change
9035 the state that is threaded.
9037 Consider the example below. The @code{square} procedure returns a value
9038 in the state monad. It returns the square of its argument, but also
9039 increments the current state value:
9043 (mlet %state-monad ((count (current-state)))
9044 (mbegin %state-monad
9045 (set-current-state (+ 1 count))
9048 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
9053 When ``run'' through @code{%state-monad}, we obtain that additional state
9054 value, which is the number of @code{square} calls.
9057 @deffn {Monadic Procedure} current-state
9058 Return the current state as a monadic value.
9061 @deffn {Monadic Procedure} set-current-state @var{value}
9062 Set the current state to @var{value} and return the previous state as a
9066 @deffn {Monadic Procedure} state-push @var{value}
9067 Push @var{value} to the current state, which is assumed to be a list,
9068 and return the previous state as a monadic value.
9071 @deffn {Monadic Procedure} state-pop
9072 Pop a value from the current state and return it as a monadic value.
9073 The state is assumed to be a list.
9076 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
9077 Run monadic value @var{mval} starting with @var{state} as the initial
9078 state. Return two values: the resulting value, and the resulting state.
9081 The main interface to the store monad, provided by the @code{(guix
9082 store)} module, is as follows.
9084 @defvr {Scheme Variable} %store-monad
9085 The store monad---an alias for @code{%state-monad}.
9087 Values in the store monad encapsulate accesses to the store. When its
9088 effect is needed, a value of the store monad must be ``evaluated'' by
9089 passing it to the @code{run-with-store} procedure (see below).
9092 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
9093 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
9094 open store connection.
9097 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
9098 Return as a monadic value the absolute file name in the store of the file
9099 containing @var{text}, a string. @var{references} is a list of store items that the
9100 resulting text file refers to; it defaults to the empty list.
9103 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
9104 Return as a monadic value the absolute file name in the store of the file
9105 containing @var{data}, a bytevector. @var{references} is a list of store
9106 items that the resulting binary file refers to; it defaults to the empty list.
9109 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
9110 [#:recursive? #t] [#:select? (const #t)]
9111 Return the name of @var{file} once interned in the store. Use
9112 @var{name} as its store name, or the basename of @var{file} if
9113 @var{name} is omitted.
9115 When @var{recursive?} is true, the contents of @var{file} are added
9116 recursively; if @var{file} designates a flat file and @var{recursive?}
9117 is true, its contents are added, and its permission bits are kept.
9119 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
9120 @var{stat})} for each directory entry, where @var{file} is the entry's
9121 absolute file name and @var{stat} is the result of @code{lstat}; exclude
9122 entries for which @var{select?} does not return true.
9124 The example below adds a file to the store, under two different names:
9127 (run-with-store (open-connection)
9128 (mlet %store-monad ((a (interned-file "README"))
9129 (b (interned-file "README" "LEGU-MIN")))
9130 (return (list a b))))
9132 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
9137 The @code{(guix packages)} module exports the following package-related
9140 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
9141 [#:system (%current-system)] [#:target #f] @
9144 value in the absolute file name of @var{file} within the @var{output}
9145 directory of @var{package}. When @var{file} is omitted, return the name
9146 of the @var{output} directory of @var{package}. When @var{target} is
9147 true, use it as a cross-compilation target triplet.
9149 Note that this procedure does @emph{not} build @var{package}. Thus, the
9150 result might or might not designate an existing file. We recommend not
9151 using this procedure unless you know what you are doing.
9154 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
9155 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
9156 @var{target} [@var{system}]
9157 Monadic version of @code{package-derivation} and
9158 @code{package-cross-derivation} (@pxref{Defining Packages}).
9163 @section G-Expressions
9165 @cindex G-expression
9166 @cindex build code quoting
9167 So we have ``derivations'', which represent a sequence of build actions
9168 to be performed to produce an item in the store (@pxref{Derivations}).
9169 These build actions are performed when asking the daemon to actually
9170 build the derivations; they are run by the daemon in a container
9171 (@pxref{Invoking guix-daemon}).
9173 @cindex code staging
9174 @cindex staging, of code
9175 @cindex strata of code
9176 It should come as no surprise that we like to write these build actions
9177 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
9178 code@footnote{The term @dfn{stratum} in this context was coined by
9179 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
9180 Kiselyov, who has written insightful
9181 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
9182 on this topic}, refers to this kind of code generation as
9183 @dfn{staging}.}: the ``host code''---code that defines packages, talks
9184 to the daemon, etc.---and the ``build code''---code that actually
9185 performs build actions, such as making directories, invoking
9186 @command{make}, and so on (@pxref{Build Phases}).
9188 To describe a derivation and its build actions, one typically needs to
9189 embed build code inside host code. It boils down to manipulating build
9190 code as data, and the homoiconicity of Scheme---code has a direct
9191 representation as data---comes in handy for that. But we need more than
9192 the normal @code{quasiquote} mechanism in Scheme to construct build
9195 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
9196 S-expressions adapted to build expressions. G-expressions, or
9197 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
9198 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
9199 @code{#$}, and @code{#$@@}), which are comparable to
9200 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
9201 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
9202 GNU Guile Reference Manual}). However, there are major differences:
9206 Gexps are meant to be written to a file and run or manipulated by other
9210 When a high-level object such as a package or derivation is unquoted
9211 inside a gexp, the result is as if its output file name had been
9215 Gexps carry information about the packages or derivations they refer to,
9216 and these dependencies are automatically added as inputs to the build
9217 processes that use them.
9220 @cindex lowering, of high-level objects in gexps
9221 This mechanism is not limited to package and derivation
9222 objects: @dfn{compilers} able to ``lower'' other high-level objects to
9223 derivations or files in the store can be defined,
9224 such that these objects can also be inserted
9225 into gexps. For example, a useful type of high-level objects that can be
9226 inserted in a gexp is ``file-like objects'', which make it easy to
9227 add files to the store and to refer to them in
9228 derivations and such (see @code{local-file} and @code{plain-file}
9231 To illustrate the idea, here is an example of a gexp:
9238 (symlink (string-append #$coreutils "/bin/ls")
9242 This gexp can be passed to @code{gexp->derivation}; we obtain a
9243 derivation that builds a directory containing exactly one symlink to
9244 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
9247 (gexp->derivation "the-thing" build-exp)
9250 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
9251 substituted to the reference to the @var{coreutils} package in the
9252 actual build code, and @var{coreutils} is automatically made an input to
9253 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
9254 output)}) is replaced by a string containing the directory name of the
9255 output of the derivation.
9257 @cindex cross compilation
9258 In a cross-compilation context, it is useful to distinguish between
9259 references to the @emph{native} build of a package---that can run on the
9260 host---versus references to cross builds of a package. To that end, the
9261 @code{#+} plays the same role as @code{#$}, but is a reference to a
9262 native package build:
9265 (gexp->derivation "vi"
9268 (mkdir (string-append #$output "/bin"))
9269 (system* (string-append #+coreutils "/bin/ln")
9271 (string-append #$emacs "/bin/emacs")
9272 (string-append #$output "/bin/vi")))
9273 #:target "aarch64-linux-gnu")
9277 In the example above, the native build of @var{coreutils} is used, so
9278 that @command{ln} can actually run on the host; but then the
9279 cross-compiled build of @var{emacs} is referenced.
9281 @cindex imported modules, for gexps
9282 @findex with-imported-modules
9283 Another gexp feature is @dfn{imported modules}: sometimes you want to be
9284 able to use certain Guile modules from the ``host environment'' in the
9285 gexp, so those modules should be imported in the ``build environment''.
9286 The @code{with-imported-modules} form allows you to express that:
9289 (let ((build (with-imported-modules '((guix build utils))
9291 (use-modules (guix build utils))
9292 (mkdir-p (string-append #$output "/bin"))))))
9293 (gexp->derivation "empty-dir"
9296 (display "success!\n")
9301 In this example, the @code{(guix build utils)} module is automatically
9302 pulled into the isolated build environment of our gexp, such that
9303 @code{(use-modules (guix build utils))} works as expected.
9305 @cindex module closure
9306 @findex source-module-closure
9307 Usually you want the @emph{closure} of the module to be imported---i.e.,
9308 the module itself and all the modules it depends on---rather than just
9309 the module; failing to do that, attempts to use the module will fail
9310 because of missing dependent modules. The @code{source-module-closure}
9311 procedure computes the closure of a module by looking at its source file
9312 headers, which comes in handy in this case:
9315 (use-modules (guix modules)) ;for 'source-module-closure'
9317 (with-imported-modules (source-module-closure
9318 '((guix build utils)
9320 (gexp->derivation "something-with-vms"
9322 (use-modules (guix build utils)
9327 @cindex extensions, for gexps
9328 @findex with-extensions
9329 In the same vein, sometimes you want to import not just pure-Scheme
9330 modules, but also ``extensions'' such as Guile bindings to C libraries
9331 or other ``full-blown'' packages. Say you need the @code{guile-json}
9332 package available on the build side, here's how you would do it:
9335 (use-modules (gnu packages guile)) ;for 'guile-json'
9337 (with-extensions (list guile-json)
9338 (gexp->derivation "something-with-json"
9340 (use-modules (json))
9344 The syntactic form to construct gexps is summarized below.
9346 @deffn {Scheme Syntax} #~@var{exp}
9347 @deffnx {Scheme Syntax} (gexp @var{exp})
9348 Return a G-expression containing @var{exp}. @var{exp} may contain one
9349 or more of the following forms:
9353 @itemx (ungexp @var{obj})
9354 Introduce a reference to @var{obj}. @var{obj} may have one of the
9355 supported types, for example a package or a
9356 derivation, in which case the @code{ungexp} form is replaced by its
9357 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
9359 If @var{obj} is a list, it is traversed and references to supported
9360 objects are substituted similarly.
9362 If @var{obj} is another gexp, its contents are inserted and its
9363 dependencies are added to those of the containing gexp.
9365 If @var{obj} is another kind of object, it is inserted as is.
9367 @item #$@var{obj}:@var{output}
9368 @itemx (ungexp @var{obj} @var{output})
9369 This is like the form above, but referring explicitly to the
9370 @var{output} of @var{obj}---this is useful when @var{obj} produces
9371 multiple outputs (@pxref{Packages with Multiple Outputs}).
9374 @itemx #+@var{obj}:output
9375 @itemx (ungexp-native @var{obj})
9376 @itemx (ungexp-native @var{obj} @var{output})
9377 Same as @code{ungexp}, but produces a reference to the @emph{native}
9378 build of @var{obj} when used in a cross compilation context.
9380 @item #$output[:@var{output}]
9381 @itemx (ungexp output [@var{output}])
9382 Insert a reference to derivation output @var{output}, or to the main
9383 output when @var{output} is omitted.
9385 This only makes sense for gexps passed to @code{gexp->derivation}.
9388 @itemx (ungexp-splicing @var{lst})
9389 Like the above, but splices the contents of @var{lst} inside the
9393 @itemx (ungexp-native-splicing @var{lst})
9394 Like the above, but refers to native builds of the objects listed in
9399 G-expressions created by @code{gexp} or @code{#~} are run-time objects
9400 of the @code{gexp?} type (see below).
9403 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
9404 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
9405 in their execution environment.
9407 Each item in @var{modules} can be the name of a module, such as
9408 @code{(guix build utils)}, or it can be a module name, followed by an
9409 arrow, followed by a file-like object:
9412 `((guix build utils)
9414 ((guix config) => ,(scheme-file "config.scm"
9415 #~(define-module @dots{}))))
9419 In the example above, the first two modules are taken from the search
9420 path, and the last one is created from the given file-like object.
9422 This form has @emph{lexical} scope: it has an effect on the gexps
9423 directly defined in @var{body}@dots{}, but not on those defined, say, in
9424 procedures called from @var{body}@dots{}.
9427 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
9428 Mark the gexps defined in @var{body}@dots{} as requiring
9429 @var{extensions} in their build and execution environment.
9430 @var{extensions} is typically a list of package objects such as those
9431 defined in the @code{(gnu packages guile)} module.
9433 Concretely, the packages listed in @var{extensions} are added to the
9434 load path while compiling imported modules in @var{body}@dots{}; they
9435 are also added to the load path of the gexp returned by
9439 @deffn {Scheme Procedure} gexp? @var{obj}
9440 Return @code{#t} if @var{obj} is a G-expression.
9443 G-expressions are meant to be written to disk, either as code building
9444 some derivation, or as plain files in the store. The monadic procedures
9445 below allow you to do that (@pxref{The Store Monad}, for more
9446 information about monads).
9448 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
9449 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
9450 [#:hash #f] [#:hash-algo #f] @
9451 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
9452 [#:module-path @code{%load-path}] @
9453 [#:effective-version "2.2"] @
9454 [#:references-graphs #f] [#:allowed-references #f] @
9455 [#:disallowed-references #f] @
9456 [#:leaked-env-vars #f] @
9457 [#:script-name (string-append @var{name} "-builder")] @
9458 [#:deprecation-warnings #f] @
9459 [#:local-build? #f] [#:substitutable? #t] @
9460 [#:properties '()] [#:guile-for-build #f]
9461 Return a derivation @var{name} that runs @var{exp} (a gexp) with
9462 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
9463 stored in a file called @var{script-name}. When @var{target} is true,
9464 it is used as the cross-compilation target triplet for packages referred
9467 @var{modules} is deprecated in favor of @code{with-imported-modules}.
9469 make @var{modules} available in the evaluation context of @var{exp};
9470 @var{modules} is a list of names of Guile modules searched in
9471 @var{module-path} to be copied in the store, compiled, and made available in
9472 the load path during the execution of @var{exp}---e.g., @code{((guix
9473 build utils) (guix build gnu-build-system))}.
9475 @var{effective-version} determines the string to use when adding extensions of
9476 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
9478 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
9481 When @var{references-graphs} is true, it must be a list of tuples of one of the
9485 (@var{file-name} @var{package})
9486 (@var{file-name} @var{package} @var{output})
9487 (@var{file-name} @var{derivation})
9488 (@var{file-name} @var{derivation} @var{output})
9489 (@var{file-name} @var{store-item})
9492 The right-hand-side of each element of @var{references-graphs} is automatically made
9493 an input of the build process of @var{exp}. In the build environment, each
9494 @var{file-name} contains the reference graph of the corresponding item, in a simple
9497 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
9498 In the latter case, the list denotes store items that the result is allowed to
9499 refer to. Any reference to another store item will lead to a build error.
9500 Similarly for @var{disallowed-references}, which can list items that must not be
9501 referenced by the outputs.
9503 @var{deprecation-warnings} determines whether to show deprecation warnings while
9504 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
9506 The other arguments are as for @code{derivation} (@pxref{Derivations}).
9509 @cindex file-like objects
9510 The @code{local-file}, @code{plain-file}, @code{computed-file},
9511 @code{program-file}, and @code{scheme-file} procedures below return
9512 @dfn{file-like objects}. That is, when unquoted in a G-expression,
9513 these objects lead to a file in the store. Consider this G-expression:
9516 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
9517 #$(local-file "/tmp/my-nscd.conf"))
9520 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
9521 to the store. Once expanded, for instance @i{via}
9522 @code{gexp->derivation}, the G-expression refers to that copy under
9523 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
9524 does not have any effect on what the G-expression does.
9525 @code{plain-file} can be used similarly; it differs in that the file
9526 content is directly passed as a string.
9528 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
9529 [#:recursive? #f] [#:select? (const #t)]
9530 Return an object representing local file @var{file} to add to the store;
9531 this object can be used in a gexp. If @var{file} is a literal string
9532 denoting a relative file name, it is looked up relative to the source
9533 file where it appears; if @var{file} is not a literal string, it is
9534 looked up relative to the current working directory at run time.
9535 @var{file} will be added to the store under @var{name}--by default the
9536 base name of @var{file}.
9538 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
9539 designates a flat file and @var{recursive?} is true, its contents are added, and its
9540 permission bits are kept.
9542 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
9543 @var{stat})} for each directory entry, where @var{file} is the entry's
9544 absolute file name and @var{stat} is the result of @code{lstat}; exclude
9545 entries for which @var{select?} does not return true.
9547 This is the declarative counterpart of the @code{interned-file} monadic
9548 procedure (@pxref{The Store Monad, @code{interned-file}}).
9551 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
9552 Return an object representing a text file called @var{name} with the given
9553 @var{content} (a string or a bytevector) to be added to the store.
9555 This is the declarative counterpart of @code{text-file}.
9558 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
9561 Return an object representing the store item @var{name}, a file or
9562 directory computed by @var{gexp}. When @var{local-build?} is true (the
9563 default), the derivation is built locally. @var{options} is a list of
9564 additional arguments to pass to @code{gexp->derivation}.
9566 This is the declarative counterpart of @code{gexp->derivation}.
9569 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
9570 [#:guile (default-guile)] [#:module-path %load-path] @
9571 [#:system (%current-system)] [#:target #f]
9572 Return an executable script @var{name} that runs @var{exp} using
9573 @var{guile}, with @var{exp}'s imported modules in its search path.
9574 Look up @var{exp}'s modules in @var{module-path}.
9576 The example below builds a script that simply invokes the @command{ls}
9580 (use-modules (guix gexp) (gnu packages base))
9582 (gexp->script "list-files"
9583 #~(execl #$(file-append coreutils "/bin/ls")
9587 When ``running'' it through the store (@pxref{The Store Monad,
9588 @code{run-with-store}}), we obtain a derivation that produces an
9589 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
9592 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
9594 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
9598 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
9599 [#:guile #f] [#:module-path %load-path]
9600 Return an object representing the executable store item @var{name} that
9601 runs @var{gexp}. @var{guile} is the Guile package used to execute that
9602 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
9604 This is the declarative counterpart of @code{gexp->script}.
9607 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
9608 [#:set-load-path? #t] [#:module-path %load-path] @
9610 [#:guile (default-guile)]
9611 Return a derivation that builds a file @var{name} containing @var{exp}.
9612 When @var{splice?} is true, @var{exp} is considered to be a list of
9613 expressions that will be spliced in the resulting file.
9615 When @var{set-load-path?} is true, emit code in the resulting file to
9616 set @code{%load-path} and @code{%load-compiled-path} to honor
9617 @var{exp}'s imported modules. Look up @var{exp}'s modules in
9620 The resulting file holds references to all the dependencies of @var{exp}
9621 or a subset thereof.
9624 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
9625 [#:splice? #f] [#:set-load-path? #t]
9626 Return an object representing the Scheme file @var{name} that contains
9629 This is the declarative counterpart of @code{gexp->file}.
9632 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
9633 Return as a monadic value a derivation that builds a text file
9634 containing all of @var{text}. @var{text} may list, in addition to
9635 strings, objects of any type that can be used in a gexp: packages,
9636 derivations, local file objects, etc. The resulting store file holds
9637 references to all these.
9639 This variant should be preferred over @code{text-file} anytime the file
9640 to create will reference items from the store. This is typically the
9641 case when building a configuration file that embeds store file names,
9645 (define (profile.sh)
9646 ;; Return the name of a shell script in the store that
9647 ;; initializes the 'PATH' environment variable.
9648 (text-file* "profile.sh"
9649 "export PATH=" coreutils "/bin:"
9650 grep "/bin:" sed "/bin\n"))
9653 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
9654 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
9655 preventing them from being garbage-collected during its lifetime.
9658 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
9659 Return an object representing store file @var{name} containing
9660 @var{text}. @var{text} is a sequence of strings and file-like objects,
9664 (mixed-text-file "profile"
9665 "export PATH=" coreutils "/bin:" grep "/bin")
9668 This is the declarative counterpart of @code{text-file*}.
9671 @deffn {Scheme Procedure} file-union @var{name} @var{files}
9672 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
9673 Each item in @var{files} must be a two-element list where the first element is the
9674 file name to use in the new directory, and the second element is a gexp
9675 denoting the target file. Here's an example:
9679 `(("hosts" ,(plain-file "hosts"
9680 "127.0.0.1 localhost"))
9681 ("bashrc" ,(plain-file "bashrc"
9682 "alias ls='ls --color=auto'"))))
9685 This yields an @code{etc} directory containing these two files.
9688 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
9689 Return a directory that is the union of @var{things}, where @var{things} is a list of
9690 file-like objects denoting directories. For example:
9693 (directory-union "guile+emacs" (list guile emacs))
9696 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
9699 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
9700 Return a file-like object that expands to the concatenation of @var{obj}
9701 and @var{suffix}, where @var{obj} is a lowerable object and each
9702 @var{suffix} is a string.
9704 As an example, consider this gexp:
9707 (gexp->script "run-uname"
9708 #~(system* #$(file-append coreutils
9712 The same effect could be achieved with:
9715 (gexp->script "run-uname"
9716 #~(system* (string-append #$coreutils
9720 There is one difference though: in the @code{file-append} case, the
9721 resulting script contains the absolute file name as a string, whereas in
9722 the second case, the resulting script contains a @code{(string-append
9723 @dots{})} expression to construct the file name @emph{at run time}.
9726 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
9727 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
9728 Bind @var{system} to the currently targeted system---e.g.,
9729 @code{"x86_64-linux"}---within @var{body}.
9731 In the second case, additionally bind @var{target} to the current
9732 cross-compilation target---a GNU triplet such as
9733 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
9736 @code{let-system} is useful in the occasional case where the object
9737 spliced into the gexp depends on the target system, as in this example:
9741 #+(let-system system
9742 (cond ((string-prefix? "armhf-" system)
9743 (file-append qemu "/bin/qemu-system-arm"))
9744 ((string-prefix? "x86_64-" system)
9745 (file-append qemu "/bin/qemu-system-x86_64"))
9748 "-net" "user" #$image)
9752 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
9753 This macro is similar to the @code{parameterize} form for
9754 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
9755 Guile Reference Manual}). The key difference is that it takes effect
9756 when the file-like object returned by @var{exp} is lowered to a
9757 derivation or store item.
9759 A typical use of @code{with-parameters} is to force the system in effect
9763 (with-parameters ((%current-system "i686-linux"))
9767 The example above returns an object that corresponds to the i686 build
9768 of Coreutils, regardless of the current value of @code{%current-system}.
9772 Of course, in addition to gexps embedded in ``host'' code, there are
9773 also modules containing build tools. To make it clear that they are
9774 meant to be used in the build stratum, these modules are kept in the
9775 @code{(guix build @dots{})} name space.
9777 @cindex lowering, of high-level objects in gexps
9778 Internally, high-level objects are @dfn{lowered}, using their compiler,
9779 to either derivations or store items. For instance, lowering a package
9780 yields a derivation, and lowering a @code{plain-file} yields a store
9781 item. This is achieved using the @code{lower-object} monadic procedure.
9783 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
9785 Return as a value in @code{%store-monad} the derivation or store item
9786 corresponding to @var{obj} for @var{system}, cross-compiling for
9787 @var{target} if @var{target} is true. @var{obj} must be an object that
9788 has an associated gexp compiler, such as a @code{<package>}.
9791 @node Invoking guix repl
9792 @section Invoking @command{guix repl}
9794 @cindex REPL, read-eval-print loop, script
9795 The @command{guix repl} command makes it easier to program Guix in Guile
9796 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
9797 programming (@pxref{Using Guile Interactively,,, guile,
9798 GNU Guile Reference Manual}), or by running Guile scripts
9799 (@pxref{Running Guile Scripts,,, guile,
9800 GNU Guile Reference Manual}).
9801 Compared to just launching the @command{guile}
9802 command, @command{guix repl} guarantees that all the Guix modules and all its
9803 dependencies are available in the search path.
9805 The general syntax is:
9808 guix repl @var{options} [@var{file} @var{args}]
9811 When a @var{file} argument is provided, @var{file} is
9812 executed as a Guile scripts:
9815 guix repl my-script.scm
9818 To pass arguments to the script, use @code{--} to prevent them from
9819 being interpreted as arguments to @command{guix repl} itself:
9822 guix repl -- my-script.scm --input=foo.txt
9825 To make a script executable directly from the shell, using the guix
9826 executable that is on the user's search path, add the following two
9827 lines at the top of the script:
9830 @code{#!/usr/bin/env -S guix repl --}
9834 Without a file name argument, a Guile REPL is started:
9838 scheme@@(guile-user)> ,use (gnu packages base)
9839 scheme@@(guile-user)> coreutils
9840 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
9844 In addition, @command{guix repl} implements a simple machine-readable REPL
9845 protocol for use by @code{(guix inferior)}, a facility to interact with
9846 @dfn{inferiors}, separate processes running a potentially different revision
9849 The available options are as follows:
9852 @item --type=@var{type}
9853 @itemx -t @var{type}
9854 Start a REPL of the given @var{TYPE}, which can be one of the following:
9858 This is default, and it spawns a standard full-featured Guile REPL.
9860 Spawn a REPL that uses the machine-readable protocol. This is the protocol
9861 that the @code{(guix inferior)} module speaks.
9864 @item --listen=@var{endpoint}
9865 By default, @command{guix repl} reads from standard input and writes to
9866 standard output. When this option is passed, it will instead listen for
9867 connections on @var{endpoint}. Here are examples of valid options:
9870 @item --listen=tcp:37146
9871 Accept connections on localhost on port 37146.
9873 @item --listen=unix:/tmp/socket
9874 Accept connections on the Unix-domain socket @file{/tmp/socket}.
9877 @item --load-path=@var{directory}
9878 @itemx -L @var{directory}
9879 Add @var{directory} to the front of the package module search path
9880 (@pxref{Package Modules}).
9882 This allows users to define their own packages and make them visible to
9886 Inhibit loading of the @file{~/.guile} file. By default, that
9887 configuration file is loaded when spawning a @code{guile} REPL.
9890 @c *********************************************************************
9894 This section describes Guix command-line utilities. Some of them are
9895 primarily targeted at developers and users who write new package
9896 definitions, while others are more generally useful. They complement
9897 the Scheme programming interface of Guix in a convenient way.
9900 * Invoking guix build:: Building packages from the command line.
9901 * Invoking guix edit:: Editing package definitions.
9902 * Invoking guix download:: Downloading a file and printing its hash.
9903 * Invoking guix hash:: Computing the cryptographic hash of a file.
9904 * Invoking guix import:: Importing package definitions.
9905 * Invoking guix refresh:: Updating package definitions.
9906 * Invoking guix lint:: Finding errors in package definitions.
9907 * Invoking guix size:: Profiling disk usage.
9908 * Invoking guix graph:: Visualizing the graph of packages.
9909 * Invoking guix publish:: Sharing substitutes.
9910 * Invoking guix challenge:: Challenging substitute servers.
9911 * Invoking guix copy:: Copying to and from a remote store.
9912 * Invoking guix container:: Process isolation.
9913 * Invoking guix weather:: Assessing substitute availability.
9914 * Invoking guix processes:: Listing client processes.
9917 @node Invoking guix build
9918 @section Invoking @command{guix build}
9920 @cindex package building
9921 @cindex @command{guix build}
9922 The @command{guix build} command builds packages or derivations and
9923 their dependencies, and prints the resulting store paths. Note that it
9924 does not modify the user's profile---this is the job of the
9925 @command{guix package} command (@pxref{Invoking guix package}). Thus,
9926 it is mainly useful for distribution developers.
9928 The general syntax is:
9931 guix build @var{options} @var{package-or-derivation}@dots{}
9934 As an example, the following command builds the latest versions of Emacs
9935 and of Guile, displays their build logs, and finally displays the
9936 resulting directories:
9939 guix build emacs guile
9942 Similarly, the following command builds all the available packages:
9945 guix build --quiet --keep-going \
9946 `guix package -A | cut -f1,2 --output-delimiter=@@`
9949 @var{package-or-derivation} may be either the name of a package found in
9950 the software distribution such as @code{coreutils} or
9951 @code{coreutils@@8.20}, or a derivation such as
9952 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
9953 package with the corresponding name (and optionally version) is searched
9954 for among the GNU distribution modules (@pxref{Package Modules}).
9956 Alternatively, the @option{--expression} option may be used to specify a
9957 Scheme expression that evaluates to a package; this is useful when
9958 disambiguating among several same-named packages or package variants is
9961 There may be zero or more @var{options}. The available options are
9962 described in the subsections below.
9965 * Common Build Options:: Build options for most commands.
9966 * Package Transformation Options:: Creating variants of packages.
9967 * Additional Build Options:: Options specific to 'guix build'.
9968 * Debugging Build Failures:: Real life packaging experience.
9971 @node Common Build Options
9972 @subsection Common Build Options
9974 A number of options that control the build process are common to
9975 @command{guix build} and other commands that can spawn builds, such as
9976 @command{guix package} or @command{guix archive}. These are the
9981 @item --load-path=@var{directory}
9982 @itemx -L @var{directory}
9983 Add @var{directory} to the front of the package module search path
9984 (@pxref{Package Modules}).
9986 This allows users to define their own packages and make them visible to
9987 the command-line tools.
9991 Keep the build tree of failed builds. Thus, if a build fails, its build
9992 tree is kept under @file{/tmp}, in a directory whose name is shown at
9993 the end of the build log. This is useful when debugging build issues.
9994 @xref{Debugging Build Failures}, for tips and tricks on how to debug
9997 This option implies @option{--no-offload}, and it has no effect when
9998 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
9999 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
10003 Keep going when some of the derivations fail to build; return only once
10004 all the builds have either completed or failed.
10006 The default behavior is to stop as soon as one of the specified
10007 derivations has failed.
10011 Do not build the derivations.
10013 @anchor{fallback-option}
10015 When substituting a pre-built binary fails, fall back to building
10016 packages locally (@pxref{Substitution Failure}).
10018 @item --substitute-urls=@var{urls}
10019 @anchor{client-substitute-urls}
10020 Consider @var{urls} the whitespace-separated list of substitute source
10021 URLs, overriding the default list of URLs of @command{guix-daemon}
10022 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
10024 This means that substitutes may be downloaded from @var{urls}, provided
10025 they are signed by a key authorized by the system administrator
10026 (@pxref{Substitutes}).
10028 When @var{urls} is the empty string, substitutes are effectively
10031 @item --no-substitutes
10032 Do not use substitutes for build products. That is, always build things
10033 locally instead of allowing downloads of pre-built binaries
10034 (@pxref{Substitutes}).
10037 Do not ``graft'' packages. In practice, this means that package updates
10038 available as grafts are not applied. @xref{Security Updates}, for more
10039 information on grafts.
10041 @item --rounds=@var{n}
10042 Build each derivation @var{n} times in a row, and raise an error if
10043 consecutive build results are not bit-for-bit identical.
10045 This is a useful way to detect non-deterministic builds processes.
10046 Non-deterministic build processes are a problem because they make it
10047 practically impossible for users to @emph{verify} whether third-party
10048 binaries are genuine. @xref{Invoking guix challenge}, for more.
10050 When used in conjunction with @option{--keep-failed}, the differing
10051 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
10052 This makes it easy to look for differences between the two results.
10055 Do not use offload builds to other machines (@pxref{Daemon Offload
10056 Setup}). That is, always build things locally instead of offloading
10057 builds to remote machines.
10059 @item --max-silent-time=@var{seconds}
10060 When the build or substitution process remains silent for more than
10061 @var{seconds}, terminate it and report a build failure.
10063 By default, the daemon's setting is honored (@pxref{Invoking
10064 guix-daemon, @option{--max-silent-time}}).
10066 @item --timeout=@var{seconds}
10067 Likewise, when the build or substitution process lasts for more than
10068 @var{seconds}, terminate it and report a build failure.
10070 By default, the daemon's setting is honored (@pxref{Invoking
10071 guix-daemon, @option{--timeout}}).
10073 @c Note: This option is actually not part of %standard-build-options but
10074 @c most programs honor it.
10075 @cindex verbosity, of the command-line tools
10076 @cindex build logs, verbosity
10077 @item -v @var{level}
10078 @itemx --verbosity=@var{level}
10079 Use the given verbosity @var{level}, an integer. Choosing 0 means that no
10080 output is produced, 1 is for quiet output, and 2 shows all the build log
10081 output on standard error.
10083 @item --cores=@var{n}
10085 Allow the use of up to @var{n} CPU cores for the build. The special
10086 value @code{0} means to use as many CPU cores as available.
10088 @item --max-jobs=@var{n}
10090 Allow at most @var{n} build jobs in parallel. @xref{Invoking
10091 guix-daemon, @option{--max-jobs}}, for details about this option and the
10092 equivalent @command{guix-daemon} option.
10094 @item --debug=@var{level}
10095 Produce debugging output coming from the build daemon. @var{level} must be an
10096 integer between 0 and 5; higher means more verbose output. Setting a level of
10097 4 or more may be helpful when debugging setup issues with the build daemon.
10101 Behind the scenes, @command{guix build} is essentially an interface to
10102 the @code{package-derivation} procedure of the @code{(guix packages)}
10103 module, and to the @code{build-derivations} procedure of the @code{(guix
10104 derivations)} module.
10106 In addition to options explicitly passed on the command line,
10107 @command{guix build} and other @command{guix} commands that support
10108 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
10110 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
10111 Users can define this variable to a list of command line options that
10112 will automatically be used by @command{guix build} and other
10113 @command{guix} commands that can perform builds, as in the example
10117 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
10120 These options are parsed independently, and the result is appended to
10121 the parsed command-line options.
10125 @node Package Transformation Options
10126 @subsection Package Transformation Options
10128 @cindex package variants
10129 Another set of command-line options supported by @command{guix build}
10130 and also @command{guix package} are @dfn{package transformation
10131 options}. These are options that make it possible to define @dfn{package
10132 variants}---for instance, packages built from different source code.
10133 This is a convenient way to create customized packages on the fly
10134 without having to type in the definitions of package variants
10135 (@pxref{Defining Packages}).
10137 Package transformation options are preserved across upgrades:
10138 @command{guix upgrade} attempts to apply transformation options
10139 initially used when creating the profile to the upgraded packages.
10141 The available options are listed below. Most commands support them and
10142 also support a @option{--help-transform} option that lists all the
10143 available options and a synopsis (these options are not shown in the
10144 @option{--help} output for brevity).
10148 @item --with-source=@var{source}
10149 @itemx --with-source=@var{package}=@var{source}
10150 @itemx --with-source=@var{package}@@@var{version}=@var{source}
10151 Use @var{source} as the source of @var{package}, and @var{version} as
10152 its version number.
10153 @var{source} must be a file name or a URL, as for @command{guix
10154 download} (@pxref{Invoking guix download}).
10156 When @var{package} is omitted,
10157 it is taken to be the package name specified on the
10158 command line that matches the base of @var{source}---e.g.,
10159 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
10160 package is @code{guile}.
10162 Likewise, when @var{version} is omitted, the version string is inferred from
10163 @var{source}; in the previous example, it is @code{2.0.10}.
10165 This option allows users to try out versions of packages other than the
10166 one provided by the distribution. The example below downloads
10167 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
10168 the @code{ed} package:
10171 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
10174 As a developer, @option{--with-source} makes it easy to test release
10178 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
10181 @dots{} or to build from a checkout in a pristine environment:
10184 $ git clone git://git.sv.gnu.org/guix.git
10185 $ guix build guix --with-source=guix@@1.0=./guix
10188 @item --with-input=@var{package}=@var{replacement}
10189 Replace dependency on @var{package} by a dependency on
10190 @var{replacement}. @var{package} must be a package name, and
10191 @var{replacement} must be a package specification such as @code{guile}
10192 or @code{guile@@1.8}.
10194 For instance, the following command builds Guix, but replaces its
10195 dependency on the current stable version of Guile with a dependency on
10196 the legacy version of Guile, @code{guile@@2.0}:
10199 guix build --with-input=guile=guile@@2.0 guix
10202 This is a recursive, deep replacement. So in this example, both
10203 @code{guix} and its dependency @code{guile-json} (which also depends on
10204 @code{guile}) get rebuilt against @code{guile@@2.0}.
10206 This is implemented using the @code{package-input-rewriting} Scheme
10207 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
10209 @item --with-graft=@var{package}=@var{replacement}
10210 This is similar to @option{--with-input} but with an important difference:
10211 instead of rebuilding the whole dependency chain, @var{replacement} is
10212 built and then @dfn{grafted} onto the binaries that were initially
10213 referring to @var{package}. @xref{Security Updates}, for more
10214 information on grafts.
10216 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
10217 and all its dependencies, replacing references to the version of GnuTLS
10218 they currently refer to:
10221 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
10224 This has the advantage of being much faster than rebuilding everything.
10225 But there is a caveat: it works if and only if @var{package} and
10226 @var{replacement} are strictly compatible---for example, if they provide
10227 a library, the application binary interface (ABI) of those libraries
10228 must be compatible. If @var{replacement} is somehow incompatible with
10229 @var{package}, then the resulting package may be unusable. Use with
10232 @cindex debugging info, rebuilding
10233 @item --with-debug-info=@var{package}
10234 Build @var{package} in a way that preserves its debugging info and graft
10235 it onto packages that depend on it. This is useful if @var{package}
10236 does not already provide debugging info as a @code{debug} output
10237 (@pxref{Installing Debugging Files}).
10239 For example, suppose you're experiencing a crash in Inkscape and would
10240 like to see what's up in GLib, a library deep down in Inkscape's
10241 dependency graph. GLib lacks a @code{debug} output, so debugging is
10242 tough. Fortunately, you rebuild GLib with debugging info and tack it on
10246 guix install inkscape --with-debug-info=glib
10249 Only GLib needs to be recompiled so this takes a reasonable amount of
10250 time. @xref{Installing Debugging Files}, for more info.
10253 Under the hood, this option works by passing the @samp{#:strip-binaries?
10254 #f} to the build system of the package of interest (@pxref{Build
10255 Systems}). Most build systems support that option but some do not. In
10256 that case, an error is raised.
10258 Likewise, if a C/C++ package is built without @code{-g} (which is rarely
10259 the case), debugging info will remain unavailable even when
10260 @code{#:strip-binaries?} is false.
10263 @cindex tool chain, changing the build tool chain of a package
10264 @item --with-c-toolchain=@var{package}=@var{toolchain}
10265 This option changes the compilation of @var{package} and everything that
10266 depends on it so that they get built with @var{toolchain} instead of the
10267 default GNU tool chain for C/C++.
10269 Consider this example:
10272 guix build octave-cli \
10273 --with-c-toolchain=fftw=gcc-toolchain@@10 \
10274 --with-c-toolchain=fftwf=gcc-toolchain@@10
10277 The command above builds a variant of the @code{fftw} and @code{fftwf}
10278 packages using version 10 of @code{gcc-toolchain} instead of the default
10279 tool chain, and then builds a variant of the GNU@tie{}Octave
10280 command-line interface using them. GNU@tie{}Octave itself is also built
10281 with @code{gcc-toolchain@@10}.
10283 This other example builds the Hardware Locality (@code{hwloc}) library
10284 and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
10288 guix build --with-c-toolchain=hwloc=clang-toolchain \
10289 intel-mpi-benchmarks
10293 There can be application binary interface (ABI) incompatibilities among
10294 tool chains. This is particularly true of the C++ standard library and
10295 run-time support libraries such as that of OpenMP. By rebuilding all
10296 dependents with the same tool chain, @option{--with-c-toolchain} minimizes
10297 the risks of incompatibility but cannot entirely eliminate them. Choose
10298 @var{package} wisely.
10301 @item --with-git-url=@var{package}=@var{url}
10302 @cindex Git, using the latest commit
10303 @cindex latest commit, building
10304 Build @var{package} from the latest commit of the @code{master} branch of the
10305 Git repository at @var{url}. Git sub-modules of the repository are fetched,
10308 For example, the following command builds the NumPy Python library against the
10309 latest commit of the master branch of Python itself:
10312 guix build python-numpy \
10313 --with-git-url=python=https://github.com/python/cpython
10316 This option can also be combined with @option{--with-branch} or
10317 @option{--with-commit} (see below).
10319 @cindex continuous integration
10320 Obviously, since it uses the latest commit of the given branch, the result of
10321 such a command varies over time. Nevertheless it is a convenient way to
10322 rebuild entire software stacks against the latest commit of one or more
10323 packages. This is particularly useful in the context of continuous
10326 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
10327 consecutive accesses to the same repository. You may want to clean it up once
10328 in a while to save disk space.
10330 @item --with-branch=@var{package}=@var{branch}
10331 Build @var{package} from the latest commit of @var{branch}. If the
10332 @code{source} field of @var{package} is an origin with the @code{git-fetch}
10333 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
10334 repository URL is taken from that @code{source}. Otherwise you have to use
10335 @option{--with-git-url} to specify the URL of the Git repository.
10337 For instance, the following command builds @code{guile-sqlite3} from the
10338 latest commit of its @code{master} branch, and then builds @code{guix} (which
10339 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
10340 specific @code{guile-sqlite3} build:
10343 guix build --with-branch=guile-sqlite3=master cuirass
10346 @item --with-commit=@var{package}=@var{commit}
10347 This is similar to @option{--with-branch}, except that it builds from
10348 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
10349 Git commit SHA1 identifier or a tag.
10351 @cindex test suite, skipping
10352 @item --without-tests=@var{package}
10353 Build @var{package} without running its tests. This can be useful in
10354 situations where you want to skip the lengthy test suite of a
10355 intermediate package, or if a package's test suite fails in a
10356 non-deterministic fashion. It should be used with care because running
10357 the test suite is a good way to ensure a package is working as intended.
10359 Turning off tests leads to a different store item. Consequently, when
10360 using this option, anything that depends on @var{package} must be
10361 rebuilt, as in this example:
10364 guix install --without-tests=python python-notebook
10367 The command above installs @code{python-notebook} on top of
10368 @code{python} built without running its test suite. To do so, it also
10369 rebuilds everything that depends on @code{python}, including
10370 @code{python-notebook} itself.
10372 Internally, @option{--without-tests} relies on changing the
10373 @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
10374 Systems}). Note that some packages use a customized @code{check} phase
10375 that does not respect a @code{#:tests? #f} setting. Therefore,
10376 @option{--without-tests} has no effect on these packages.
10380 Wondering how to achieve the same effect using Scheme code, for example
10381 in your manifest, or how to write your own package transformation?
10382 @xref{Defining Package Variants}, for an overview of the programming
10383 interfaces available.
10385 @node Additional Build Options
10386 @subsection Additional Build Options
10388 The command-line options presented below are specific to @command{guix
10395 Build quietly, without displaying the build log; this is equivalent to
10396 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
10397 (or similar) and can always be retrieved using the @option{--log-file} option.
10399 @item --file=@var{file}
10400 @itemx -f @var{file}
10401 Build the package, derivation, or other file-like object that the code within
10402 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
10404 As an example, @var{file} might contain a package definition like this
10405 (@pxref{Defining Packages}):
10408 @include package-hello.scm
10411 The @var{file} may also contain a JSON representation of one or more
10412 package definitions. Running @code{guix build -f} on @file{hello.json}
10413 with the following contents would result in building the packages
10414 @code{myhello} and @code{greeter}:
10417 @verbatiminclude package-hello.json
10420 @item --manifest=@var{manifest}
10421 @itemx -m @var{manifest}
10422 Build all packages listed in the given @var{manifest}
10423 (@pxref{profile-manifest, @option{--manifest}}).
10425 @item --expression=@var{expr}
10426 @itemx -e @var{expr}
10427 Build the package or derivation @var{expr} evaluates to.
10429 For example, @var{expr} may be @code{(@@ (gnu packages guile)
10430 guile-1.8)}, which unambiguously designates this specific variant of
10431 version 1.8 of Guile.
10433 Alternatively, @var{expr} may be a G-expression, in which case it is used
10434 as a build program passed to @code{gexp->derivation}
10435 (@pxref{G-Expressions}).
10437 Lastly, @var{expr} may refer to a zero-argument monadic procedure
10438 (@pxref{The Store Monad}). The procedure must return a derivation as a
10439 monadic value, which is then passed through @code{run-with-store}.
10443 Build the source derivations of the packages, rather than the packages
10446 For instance, @code{guix build -S gcc} returns something like
10447 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
10450 The returned source tarball is the result of applying any patches and
10451 code snippets specified in the package @code{origin} (@pxref{Defining
10454 @cindex source, verification
10455 As with other derivations, the result of building a source derivation
10456 can be verified using the @option{--check} option (@pxref{build-check}).
10457 This is useful to validate that a (potentially already built or
10458 substituted, thus cached) package source matches against its declared
10461 Note that @command{guix build -S} compiles the sources only of the
10462 specified packages. They do not include the sources of statically
10463 linked dependencies and by themselves are insufficient for reproducing
10467 Fetch and return the source of @var{package-or-derivation} and all their
10468 dependencies, recursively. This is a handy way to obtain a local copy
10469 of all the source code needed to build @var{packages}, allowing you to
10470 eventually build them even without network access. It is an extension
10471 of the @option{--source} option and can accept one of the following
10472 optional argument values:
10476 This value causes the @option{--sources} option to behave in the same way
10477 as the @option{--source} option.
10480 Build the source derivations of all packages, including any source that
10481 might be listed as @code{inputs}. This is the default value.
10484 $ guix build --sources tzdata
10485 The following derivations will be built:
10486 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
10487 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
10491 Build the source derivations of all packages, as well of all transitive
10492 inputs to the packages. This can be used e.g.@: to
10493 prefetch package source for later offline building.
10496 $ guix build --sources=transitive tzdata
10497 The following derivations will be built:
10498 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
10499 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
10500 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
10501 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
10502 /gnu/store/@dots{}-make-4.1.tar.xz.drv
10503 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
10509 @item --system=@var{system}
10510 @itemx -s @var{system}
10511 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
10512 the system type of the build host. The @command{guix build} command allows
10513 you to repeat this option several times, in which case it builds for all the
10514 specified systems; other commands ignore extraneous @option{-s} options.
10517 The @option{--system} flag is for @emph{native} compilation and must not
10518 be confused with cross-compilation. See @option{--target} below for
10519 information on cross-compilation.
10522 An example use of this is on Linux-based systems, which can emulate
10523 different personalities. For instance, passing
10524 @option{--system=i686-linux} on an @code{x86_64-linux} system or
10525 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
10526 you to build packages in a complete 32-bit environment.
10529 Building for an @code{armhf-linux} system is unconditionally enabled on
10530 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
10531 allow for this functionality, notably the ThunderX.
10534 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
10535 is enabled (@pxref{Virtualization Services,
10536 @code{qemu-binfmt-service-type}}), you can build for any system for
10537 which a QEMU @code{binfmt_misc} handler is installed.
10539 Builds for a system other than that of the machine you are using can
10540 also be offloaded to a remote machine of the right architecture.
10541 @xref{Daemon Offload Setup}, for more information on offloading.
10543 @item --target=@var{triplet}
10544 @cindex cross-compilation
10545 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
10546 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
10547 configuration triplets,, autoconf, Autoconf}).
10549 @anchor{build-check}
10551 @cindex determinism, checking
10552 @cindex reproducibility, checking
10553 Rebuild @var{package-or-derivation}, which are already available in the
10554 store, and raise an error if the build results are not bit-for-bit
10557 This mechanism allows you to check whether previously installed
10558 substitutes are genuine (@pxref{Substitutes}), or whether the build result
10559 of a package is deterministic. @xref{Invoking guix challenge}, for more
10560 background information and tools.
10562 When used in conjunction with @option{--keep-failed}, the differing
10563 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
10564 This makes it easy to look for differences between the two results.
10567 @cindex repairing store items
10568 @cindex corruption, recovering from
10569 Attempt to repair the specified store items, if they are corrupt, by
10570 re-downloading or rebuilding them.
10572 This operation is not atomic and thus restricted to @code{root}.
10574 @item --derivations
10576 Return the derivation paths, not the output paths, of the given
10579 @item --root=@var{file}
10580 @itemx -r @var{file}
10581 @cindex GC roots, adding
10582 @cindex garbage collector roots, adding
10583 Make @var{file} a symlink to the result, and register it as a garbage
10586 Consequently, the results of this @command{guix build} invocation are
10587 protected from garbage collection until @var{file} is removed. When
10588 that option is omitted, build results are eligible for garbage
10589 collection as soon as the build completes. @xref{Invoking guix gc}, for
10593 @cindex build logs, access
10594 Return the build log file names or URLs for the given
10595 @var{package-or-derivation}, or raise an error if build logs are
10598 This works regardless of how packages or derivations are specified. For
10599 instance, the following invocations are equivalent:
10602 guix build --log-file `guix build -d guile`
10603 guix build --log-file `guix build guile`
10604 guix build --log-file guile
10605 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
10608 If a log is unavailable locally, and unless @option{--no-substitutes} is
10609 passed, the command looks for a corresponding log on one of the
10610 substitute servers (as specified with @option{--substitute-urls}).
10612 So for instance, imagine you want to see the build log of GDB on MIPS,
10613 but you are actually on an @code{x86_64} machine:
10616 $ guix build --log-file gdb -s aarch64-linux
10617 https://@value{SUBSTITUTE-SERVER}/log/@dots{}-gdb-7.10
10620 You can freely access a huge library of build logs!
10623 @node Debugging Build Failures
10624 @subsection Debugging Build Failures
10626 @cindex build failures, debugging
10627 When defining a new package (@pxref{Defining Packages}), you will
10628 probably find yourself spending some time debugging and tweaking the
10629 build until it succeeds. To do that, you need to operate the build
10630 commands yourself in an environment as close as possible to the one the
10633 To that end, the first thing to do is to use the @option{--keep-failed}
10634 or @option{-K} option of @command{guix build}, which will keep the
10635 failed build tree in @file{/tmp} or whatever directory you specified as
10636 @env{TMPDIR} (@pxref{Invoking guix build, @option{--keep-failed}}).
10638 From there on, you can @command{cd} to the failed build tree and source
10639 the @file{environment-variables} file, which contains all the
10640 environment variable definitions that were in place when the build
10641 failed. So let's say you're debugging a build failure in package
10642 @code{foo}; a typical session would look like this:
10645 $ guix build foo -K
10646 @dots{} @i{build fails}
10647 $ cd /tmp/guix-build-foo.drv-0
10648 $ source ./environment-variables
10652 Now, you can invoke commands as if you were the daemon (almost) and
10653 troubleshoot your build process.
10655 Sometimes it happens that, for example, a package's tests pass when you
10656 run them manually but they fail when the daemon runs them. This can
10657 happen because the daemon runs builds in containers where, unlike in our
10658 environment above, network access is missing, @file{/bin/sh} does not
10659 exist, etc. (@pxref{Build Environment Setup}).
10661 In such cases, you may need to run inspect the build process from within
10662 a container similar to the one the build daemon creates:
10665 $ guix build -K foo
10667 $ cd /tmp/guix-build-foo.drv-0
10668 $ guix environment --no-grafts -C foo --ad-hoc strace gdb
10669 [env]# source ./environment-variables
10673 Here, @command{guix environment -C} creates a container and spawns a new
10674 shell in it (@pxref{Invoking guix environment}). The @command{--ad-hoc
10675 strace gdb} part adds the @command{strace} and @command{gdb} commands to
10676 the container, which you may find handy while debugging. The
10677 @option{--no-grafts} option makes sure we get the exact same
10678 environment, with ungrafted packages (@pxref{Security Updates}, for more
10681 To get closer to a container like that used by the build daemon, we can
10682 remove @file{/bin/sh}:
10688 (Don't worry, this is harmless: this is all happening in the throw-away
10689 container created by @command{guix environment}.)
10691 The @command{strace} command is probably not in the search path, but we
10695 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
10698 In this way, not only you will have reproduced the environment variables
10699 the daemon uses, you will also be running the build process in a container
10700 similar to the one the daemon uses.
10703 @node Invoking guix edit
10704 @section Invoking @command{guix edit}
10706 @cindex @command{guix edit}
10707 @cindex package definition, editing
10708 So many packages, so many source files! The @command{guix edit} command
10709 facilitates the life of users and packagers by pointing their editor at
10710 the source file containing the definition of the specified packages.
10714 guix edit gcc@@4.9 vim
10718 launches the program specified in the @env{VISUAL} or in the
10719 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
10722 If you are using a Guix Git checkout (@pxref{Building from Git}), or
10723 have created your own packages on @env{GUIX_PACKAGE_PATH}
10724 (@pxref{Package Modules}), you will be able to edit the package
10725 recipes. In other cases, you will be able to examine the read-only recipes
10726 for packages currently in the store.
10728 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
10729 @option{--load-path=@var{directory}} (or in short @option{-L
10730 @var{directory}}) allows you to add @var{directory} to the front of the
10731 package module search path and so make your own packages visible.
10733 @node Invoking guix download
10734 @section Invoking @command{guix download}
10736 @cindex @command{guix download}
10737 @cindex downloading package sources
10738 When writing a package definition, developers typically need to download
10739 a source tarball, compute its SHA256 hash, and write that
10740 hash in the package definition (@pxref{Defining Packages}). The
10741 @command{guix download} tool helps with this task: it downloads a file
10742 from the given URI, adds it to the store, and prints both its file name
10743 in the store and its SHA256 hash.
10745 The fact that the downloaded file is added to the store saves bandwidth:
10746 when the developer eventually tries to build the newly defined package
10747 with @command{guix build}, the source tarball will not have to be
10748 downloaded again because it is already in the store. It is also a
10749 convenient way to temporarily stash files, which may be deleted
10750 eventually (@pxref{Invoking guix gc}).
10752 The @command{guix download} command supports the same URIs as used in
10753 package definitions. In particular, it supports @code{mirror://} URIs.
10754 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
10755 Guile bindings for GnuTLS are available in the user's environment; when
10756 they are not available, an error is raised. @xref{Guile Preparations,
10757 how to install the GnuTLS bindings for Guile,, gnutls-guile,
10758 GnuTLS-Guile}, for more information.
10760 @command{guix download} verifies HTTPS server certificates by loading
10761 the certificates of X.509 authorities from the directory pointed to by
10762 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
10763 Certificates}), unless @option{--no-check-certificate} is used.
10765 The following options are available:
10768 @item --hash=@var{algorithm}
10769 @itemx -H @var{algorithm}
10770 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
10771 hash}, for more information.
10773 @item --format=@var{fmt}
10774 @itemx -f @var{fmt}
10775 Write the hash in the format specified by @var{fmt}. For more
10776 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
10778 @item --no-check-certificate
10779 Do not validate the X.509 certificates of HTTPS servers.
10781 When using this option, you have @emph{absolutely no guarantee} that you
10782 are communicating with the authentic server responsible for the given
10783 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
10785 @item --output=@var{file}
10786 @itemx -o @var{file}
10787 Save the downloaded file to @var{file} instead of adding it to the
10791 @node Invoking guix hash
10792 @section Invoking @command{guix hash}
10794 @cindex @command{guix hash}
10795 The @command{guix hash} command computes the hash of a file.
10796 It is primarily a convenience tool for anyone contributing to the
10797 distribution: it computes the cryptographic hash of a file, which can be
10798 used in the definition of a package (@pxref{Defining Packages}).
10800 The general syntax is:
10803 guix hash @var{option} @var{file}
10806 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
10807 hash of data read from standard input. @command{guix hash} has the
10812 @item --hash=@var{algorithm}
10813 @itemx -H @var{algorithm}
10814 Compute a hash using the specified @var{algorithm}, @code{sha256} by
10817 @var{algorithm} must the name of a cryptographic hash algorithm
10818 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
10819 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
10820 Reference Manual}).
10822 @item --format=@var{fmt}
10823 @itemx -f @var{fmt}
10824 Write the hash in the format specified by @var{fmt}.
10826 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
10827 (@code{hex} and @code{hexadecimal} can be used as well).
10829 If the @option{--format} option is not specified, @command{guix hash}
10830 will output the hash in @code{nix-base32}. This representation is used
10831 in the definitions of packages.
10835 Compute the hash on @var{file} recursively.
10837 In this case, the hash is computed on an archive containing @var{file},
10838 including its children if it is a directory. Some of the metadata of
10839 @var{file} is part of the archive; for instance, when @var{file} is a
10840 regular file, the hash is different depending on whether @var{file} is
10841 executable or not. Metadata such as time stamps has no impact on the
10842 hash (@pxref{Invoking guix archive}).
10843 @c FIXME: Replace xref above with xref to an ``Archive'' section when
10846 @item --exclude-vcs
10848 When combined with @option{--recursive}, exclude version control system
10849 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
10852 As an example, here is how you would compute the hash of a Git checkout,
10853 which is useful when using the @code{git-fetch} method (@pxref{origin
10857 $ git clone http://example.org/foo.git
10863 @node Invoking guix import
10864 @section Invoking @command{guix import}
10866 @cindex importing packages
10867 @cindex package import
10868 @cindex package conversion
10869 @cindex Invoking @command{guix import}
10870 The @command{guix import} command is useful for people who would like to
10871 add a package to the distribution with as little work as
10872 possible---a legitimate demand. The command knows of a few
10873 repositories from which it can ``import'' package metadata. The result
10874 is a package definition, or a template thereof, in the format we know
10875 (@pxref{Defining Packages}).
10877 The general syntax is:
10880 guix import @var{importer} @var{options}@dots{}
10883 @var{importer} specifies the source from which to import package
10884 metadata, and @var{options} specifies a package identifier and other
10885 options specific to @var{importer}.
10887 Some of the importers rely on the ability to run the @command{gpgv} command.
10888 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
10891 Currently, the available ``importers'' are:
10895 Import metadata for the given GNU package. This provides a template
10896 for the latest version of that GNU package, including the hash of its
10897 source tarball, and its canonical synopsis and description.
10899 Additional information such as the package dependencies and its
10900 license needs to be figured out manually.
10902 For example, the following command returns a package definition for
10906 guix import gnu hello
10909 Specific command-line options are:
10912 @item --key-download=@var{policy}
10913 As for @command{guix refresh}, specify the policy to handle missing
10914 OpenPGP keys when verifying the package signature. @xref{Invoking guix
10915 refresh, @option{--key-download}}.
10920 Import metadata from the @uref{https://pypi.python.org/, Python Package
10921 Index}. Information is taken from the JSON-formatted description
10922 available at @code{pypi.python.org} and usually includes all the relevant
10923 information, including package dependencies. For maximum efficiency, it
10924 is recommended to install the @command{unzip} utility, so that the
10925 importer can unzip Python wheels and gather data from them.
10927 The command below imports metadata for the @code{itsdangerous} Python
10931 guix import pypi itsdangerous
10937 Traverse the dependency graph of the given upstream package recursively
10938 and generate package expressions for all those packages that are not yet
10944 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
10945 is taken from the JSON-formatted description available at
10946 @code{rubygems.org} and includes most relevant information, including
10947 runtime dependencies. There are some caveats, however. The metadata
10948 doesn't distinguish between synopses and descriptions, so the same string
10949 is used for both fields. Additionally, the details of non-Ruby
10950 dependencies required to build native extensions is unavailable and left
10951 as an exercise to the packager.
10953 The command below imports metadata for the @code{rails} Ruby package:
10956 guix import gem rails
10962 Traverse the dependency graph of the given upstream package recursively
10963 and generate package expressions for all those packages that are not yet
10969 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
10970 Information is taken from the JSON-formatted metadata provided through
10971 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
10972 relevant information, such as module dependencies. License information
10973 should be checked closely. If Perl is available in the store, then the
10974 @code{corelist} utility will be used to filter core modules out of the
10975 list of dependencies.
10977 The command command below imports metadata for the Acme::Boolean Perl
10981 guix import cpan Acme::Boolean
10986 @cindex Bioconductor
10987 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
10988 central repository for the @uref{https://r-project.org, GNU@tie{}R
10989 statistical and graphical environment}.
10991 Information is extracted from the @file{DESCRIPTION} file of the package.
10993 The command command below imports metadata for the Cairo R package:
10996 guix import cran Cairo
10999 When @option{--recursive} is added, the importer will traverse the
11000 dependency graph of the given upstream package recursively and generate
11001 package expressions for all those packages that are not yet in Guix.
11003 When @option{--archive=bioconductor} is added, metadata is imported from
11004 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
11005 packages for the analysis and comprehension of high-throughput
11006 genomic data in bioinformatics.
11008 Information is extracted from the @file{DESCRIPTION} file contained in the
11011 The command below imports metadata for the GenomicRanges R package:
11014 guix import cran --archive=bioconductor GenomicRanges
11017 Finally, you can also import R packages that have not yet been published on
11018 CRAN or Bioconductor as long as they are in a git repository. Use
11019 @option{--archive=git} followed by the URL of the git repository:
11022 guix import cran --archive=git https://github.com/immunogenomics/harmony
11028 Import metadata from @uref{https://www.ctan.org/, CTAN}, the
11029 comprehensive TeX archive network for TeX packages that are part of the
11030 @uref{https://www.tug.org/texlive/, TeX Live distribution}.
11032 Information about the package is obtained through the XML API provided
11033 by CTAN, while the source code is downloaded from the SVN repository of
11034 the Tex Live project. This is done because the CTAN does not keep
11035 versioned archives.
11037 The command command below imports metadata for the @code{fontspec}
11041 guix import texlive fontspec
11044 When @option{--archive=@var{directory}} is added, the source code is
11045 downloaded not from the @file{latex} sub-directory of the
11046 @file{texmf-dist/source} tree in the TeX Live SVN repository, but from
11047 the specified sibling @var{directory} under the same root.
11049 The command below imports metadata for the @code{ifxetex} package from
11050 CTAN while fetching the sources from the directory
11051 @file{texmf/source/generic}:
11054 guix import texlive --archive=generic ifxetex
11058 @cindex JSON, import
11059 Import package metadata from a local JSON file. Consider the following
11060 example package definition in JSON format:
11066 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
11067 "build-system": "gnu",
11068 "home-page": "https://www.gnu.org/software/hello/",
11069 "synopsis": "Hello, GNU world: An example GNU package",
11070 "description": "GNU Hello prints a greeting.",
11071 "license": "GPL-3.0+",
11072 "native-inputs": ["gettext"]
11076 The field names are the same as for the @code{<package>} record
11077 (@xref{Defining Packages}). References to other packages are provided
11078 as JSON lists of quoted package specification strings such as
11079 @code{guile} or @code{guile@@2.0}.
11081 The importer also supports a more explicit source definition using the
11082 common fields for @code{<origin>} records:
11088 "method": "url-fetch",
11089 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
11091 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
11098 The command below reads metadata from the JSON file @code{hello.json}
11099 and outputs a package expression:
11102 guix import json hello.json
11106 Import metadata from a local copy of the source of the
11107 @uref{https://nixos.org/nixpkgs/, Nixpkgs distribution}@footnote{This
11108 relies on the @command{nix-instantiate} command of
11109 @uref{https://nixos.org/nix/, Nix}.}. Package definitions in Nixpkgs are
11110 typically written in a mixture of Nix-language and Bash code. This
11111 command only imports the high-level package structure that is written in
11112 the Nix language. It normally includes all the basic fields of a
11113 package definition.
11115 When importing a GNU package, the synopsis and descriptions are replaced
11116 by their canonical upstream variant.
11118 Usually, you will first need to do:
11121 export NIX_REMOTE=daemon
11125 so that @command{nix-instantiate} does not try to open the Nix database.
11127 As an example, the command below imports the package definition of
11128 LibreOffice (more precisely, it imports the definition of the package
11129 bound to the @code{libreoffice} top-level attribute):
11132 guix import nix ~/path/to/nixpkgs libreoffice
11137 Import metadata from the Haskell community's central package archive
11138 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
11139 Cabal files and includes all the relevant information, including package
11142 Specific command-line options are:
11147 Read a Cabal file from standard input.
11148 @item --no-test-dependencies
11150 Do not include dependencies required only by the test suites.
11151 @item --cabal-environment=@var{alist}
11152 @itemx -e @var{alist}
11153 @var{alist} is a Scheme alist defining the environment in which the
11154 Cabal conditionals are evaluated. The accepted keys are: @code{os},
11155 @code{arch}, @code{impl} and a string representing the name of a flag.
11156 The value associated with a flag has to be either the symbol
11157 @code{true} or @code{false}. The value associated with other keys
11158 has to conform to the Cabal file format definition. The default value
11159 associated with the keys @code{os}, @code{arch} and @code{impl} is
11160 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
11163 Traverse the dependency graph of the given upstream package recursively
11164 and generate package expressions for all those packages that are not yet
11168 The command below imports metadata for the latest version of the
11169 HTTP Haskell package without including test dependencies and
11170 specifying the value of the flag @samp{network-uri} as @code{false}:
11173 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
11176 A specific package version may optionally be specified by following the
11177 package name by an at-sign and a version number as in the following example:
11180 guix import hackage mtl@@2.1.3.1
11185 The @code{stackage} importer is a wrapper around the @code{hackage} one.
11186 It takes a package name, looks up the package version included in a
11187 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
11188 release and uses the @code{hackage} importer to retrieve its metadata.
11189 Note that it is up to you to select an LTS release compatible with the
11190 GHC compiler used by Guix.
11192 Specific command-line options are:
11195 @item --no-test-dependencies
11197 Do not include dependencies required only by the test suites.
11198 @item --lts-version=@var{version}
11199 @itemx -l @var{version}
11200 @var{version} is the desired LTS release version. If omitted the latest
11204 Traverse the dependency graph of the given upstream package recursively
11205 and generate package expressions for all those packages that are not yet
11209 The command below imports metadata for the HTTP Haskell package
11210 included in the LTS Stackage release version 7.18:
11213 guix import stackage --lts-version=7.18 HTTP
11218 Import metadata from an Emacs Lisp Package Archive (ELPA) package
11219 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
11221 Specific command-line options are:
11224 @item --archive=@var{repo}
11225 @itemx -a @var{repo}
11226 @var{repo} identifies the archive repository from which to retrieve the
11227 information. Currently the supported repositories and their identifiers
11231 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
11232 identifier. This is the default.
11234 Packages from @code{elpa.gnu.org} are signed with one of the keys
11235 contained in the GnuPG keyring at
11236 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
11237 @code{emacs} package (@pxref{Package Installation, ELPA package
11238 signatures,, emacs, The GNU Emacs Manual}).
11241 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
11242 @code{melpa-stable} identifier.
11245 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
11251 Traverse the dependency graph of the given upstream package recursively
11252 and generate package expressions for all those packages that are not yet
11258 Import metadata from the crates.io Rust package repository
11259 @uref{https://crates.io, crates.io}, as in this example:
11262 guix import crate blake2-rfc
11265 The crate importer also allows you to specify a version string:
11268 guix import crate constant-time-eq@@0.1.0
11271 Additional options include:
11276 Traverse the dependency graph of the given upstream package recursively
11277 and generate package expressions for all those packages that are not yet
11284 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
11285 repository used by the OCaml community.
11288 The structure of the @command{guix import} code is modular. It would be
11289 useful to have more importers for other package formats, and your help
11290 is welcome here (@pxref{Contributing}).
11292 @node Invoking guix refresh
11293 @section Invoking @command{guix refresh}
11295 @cindex @command {guix refresh}
11296 The primary audience of the @command{guix refresh} command is developers
11297 of the GNU software distribution. By default, it reports any packages
11298 provided by the distribution that are outdated compared to the latest
11299 upstream version, like this:
11303 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
11304 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
11307 Alternatively, one can specify packages to consider, in which case a
11308 warning is emitted for packages that lack an updater:
11311 $ guix refresh coreutils guile guile-ssh
11312 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
11313 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
11316 @command{guix refresh} browses the upstream repository of each package and determines
11317 the highest version number of the releases therein. The command
11318 knows how to update specific types of packages: GNU packages, ELPA
11319 packages, etc.---see the documentation for @option{--type} below. There
11320 are many packages, though, for which it lacks a method to determine
11321 whether a new upstream release is available. However, the mechanism is
11322 extensible, so feel free to get in touch with us to add a new method!
11327 Consider the packages specified, and all the packages upon which they depend.
11330 $ guix refresh --recursive coreutils
11331 gnu/packages/acl.scm:35:2: warning: no updater for acl
11332 gnu/packages/m4.scm:30:12: info: 1.4.18 is already the latest version of m4
11333 gnu/packages/xml.scm:68:2: warning: no updater for expat
11334 gnu/packages/multiprecision.scm:40:12: info: 6.1.2 is already the latest version of gmp
11340 Sometimes the upstream name differs from the package name used in Guix,
11341 and @command{guix refresh} needs a little help. Most updaters honor the
11342 @code{upstream-name} property in package definitions, which can be used
11346 (define-public network-manager
11348 (name "network-manager")
11350 (properties '((upstream-name . "NetworkManager")))))
11353 When passed @option{--update}, it modifies distribution source files to
11354 update the version numbers and source tarball hashes of those package
11355 recipes (@pxref{Defining Packages}). This is achieved by downloading
11356 each package's latest source tarball and its associated OpenPGP
11357 signature, authenticating the downloaded tarball against its signature
11358 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
11359 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
11362 key used to sign the tarball is missing from the user's keyring, an
11363 attempt is made to automatically retrieve it from a public key server;
11364 when this is successful, the key is added to the user's keyring; otherwise,
11365 @command{guix refresh} reports an error.
11367 The following options are supported:
11371 @item --expression=@var{expr}
11372 @itemx -e @var{expr}
11373 Consider the package @var{expr} evaluates to.
11375 This is useful to precisely refer to a package, as in this example:
11378 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
11381 This command lists the dependents of the ``final'' libc (essentially all
11386 Update distribution source files (package recipes) in place. This is
11387 usually run from a checkout of the Guix source tree (@pxref{Running
11388 Guix Before It Is Installed}):
11391 $ ./pre-inst-env guix refresh -s non-core -u
11394 @xref{Defining Packages}, for more information on package definitions.
11396 @item --select=[@var{subset}]
11397 @itemx -s @var{subset}
11398 Select all the packages in @var{subset}, one of @code{core} or
11401 The @code{core} subset refers to all the packages at the core of the
11402 distribution---i.e., packages that are used to build ``everything
11403 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
11404 changing one of these packages in the distribution entails a rebuild of
11405 all the others. Thus, such updates are an inconvenience to users in
11406 terms of build time or bandwidth used to achieve the upgrade.
11408 The @code{non-core} subset refers to the remaining packages. It is
11409 typically useful in cases where an update of the core packages would be
11412 @item --manifest=@var{file}
11413 @itemx -m @var{file}
11414 Select all the packages from the manifest in @var{file}. This is useful to
11415 check if any packages of the user manifest can be updated.
11417 @item --type=@var{updater}
11418 @itemx -t @var{updater}
11419 Select only packages handled by @var{updater} (may be a comma-separated
11420 list of updaters). Currently, @var{updater} may be one of:
11424 the updater for GNU packages;
11426 the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
11428 the updater for GNOME packages;
11430 the updater for KDE packages;
11432 the updater for X.org packages;
11434 the updater for packages hosted on kernel.org;
11436 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
11438 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
11440 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
11442 the updater for @uref{https://www.cpan.org/, CPAN} packages;
11444 the updater for @uref{https://pypi.python.org, PyPI} packages.
11446 the updater for @uref{https://rubygems.org, RubyGems} packages.
11448 the updater for @uref{https://github.com, GitHub} packages.
11450 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
11452 the updater for @uref{https://www.stackage.org, Stackage} packages.
11454 the updater for @uref{https://crates.io, Crates} packages.
11456 the updater for @uref{https://launchpad.net, Launchpad} packages.
11459 For instance, the following command only checks for updates of Emacs
11460 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
11463 $ guix refresh --type=elpa,cran
11464 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
11465 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
11470 In addition, @command{guix refresh} can be passed one or more package
11471 names, as in this example:
11474 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
11478 The command above specifically updates the @code{emacs} and
11479 @code{idutils} packages. The @option{--select} option would have no
11480 effect in this case.
11482 When considering whether to upgrade a package, it is sometimes
11483 convenient to know which packages would be affected by the upgrade and
11484 should be checked for compatibility. For this the following option may
11485 be used when passing @command{guix refresh} one or more package names:
11489 @item --list-updaters
11491 List available updaters and exit (see @option{--type} above).
11493 For each updater, display the fraction of packages it covers; at the
11494 end, display the fraction of packages covered by all these updaters.
11496 @item --list-dependent
11498 List top-level dependent packages that would need to be rebuilt as a
11499 result of upgrading one or more packages.
11501 @xref{Invoking guix graph, the @code{reverse-package} type of
11502 @command{guix graph}}, for information on how to visualize the list of
11503 dependents of a package.
11507 Be aware that the @option{--list-dependent} option only
11508 @emph{approximates} the rebuilds that would be required as a result of
11509 an upgrade. More rebuilds might be required under some circumstances.
11512 $ guix refresh --list-dependent flex
11513 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
11514 hop@@2.4.0 geiser@@0.4 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
11517 The command above lists a set of packages that could be built to check
11518 for compatibility with an upgraded @code{flex} package.
11522 @item --list-transitive
11523 List all the packages which one or more packages depend upon.
11526 $ guix refresh --list-transitive flex
11527 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
11528 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{}
11533 The command above lists a set of packages which, when changed, would cause
11534 @code{flex} to be rebuilt.
11536 The following options can be used to customize GnuPG operation:
11540 @item --gpg=@var{command}
11541 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
11542 for in @code{$PATH}.
11544 @item --keyring=@var{file}
11545 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
11546 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
11547 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
11548 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
11549 information on a tool to manipulate keybox files).
11551 When this option is omitted, @command{guix refresh} uses
11552 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
11553 signing keys. OpenPGP signatures are checked against keys from this keyring;
11554 missing keys are downloaded to this keyring as well (see
11555 @option{--key-download} below).
11557 You can export keys from your default GPG keyring into a keybox file using
11558 commands like this one:
11561 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
11564 Likewise, you can fetch keys to a specific keybox file like this:
11567 gpg --no-default-keyring --keyring mykeyring.kbx \
11568 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
11571 @ref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
11572 Privacy Guard}, for more information on GPG's @option{--keyring} option.
11574 @item --key-download=@var{policy}
11575 Handle missing OpenPGP keys according to @var{policy}, which may be one
11580 Always download missing OpenPGP keys from the key server, and add them
11581 to the user's GnuPG keyring.
11584 Never try to download missing OpenPGP keys. Instead just bail out.
11587 When a package signed with an unknown OpenPGP key is encountered, ask
11588 the user whether to download it or not. This is the default behavior.
11591 @item --key-server=@var{host}
11592 Use @var{host} as the OpenPGP key server when importing a public key.
11594 @item --load-path=@var{directory}
11595 Add @var{directory} to the front of the package module search path
11596 (@pxref{Package Modules}).
11598 This allows users to define their own packages and make them visible to
11599 the command-line tools.
11603 The @code{github} updater uses the
11604 @uref{https://developer.github.com/v3/, GitHub API} to query for new
11605 releases. When used repeatedly e.g.@: when refreshing all packages,
11606 GitHub will eventually refuse to answer any further API requests. By
11607 default 60 API requests per hour are allowed, and a full refresh on all
11608 GitHub packages in Guix requires more than this. Authentication with
11609 GitHub through the use of an API token alleviates these limits. To use
11610 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
11611 token procured from @uref{https://github.com/settings/tokens} or
11615 @node Invoking guix lint
11616 @section Invoking @command{guix lint}
11618 @cindex @command{guix lint}
11619 @cindex package, checking for errors
11620 The @command{guix lint} command is meant to help package developers avoid
11621 common errors and use a consistent style. It runs a number of checks on
11622 a given set of packages in order to find common mistakes in their
11623 definitions. Available @dfn{checkers} include (see
11624 @option{--list-checkers} for a complete list):
11629 Validate certain typographical and stylistic rules about package
11630 descriptions and synopses.
11632 @item inputs-should-be-native
11633 Identify inputs that should most likely be native inputs.
11639 @itemx source-file-name
11640 Probe @code{home-page} and @code{source} URLs and report those that are
11641 invalid. Suggest a @code{mirror://} URL when applicable. If the
11642 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
11643 URL. Check that the source file name is meaningful, e.g.@: is not just a
11644 version number or ``git-checkout'', without a declared @code{file-name}
11645 (@pxref{origin Reference}).
11647 @item source-unstable-tarball
11648 Parse the @code{source} URL to determine if a tarball from GitHub is
11649 autogenerated or if it is a release tarball. Unfortunately GitHub's
11650 autogenerated tarballs are sometimes regenerated.
11653 Check that the derivation of the given packages can be successfully
11654 computed for all the supported systems (@pxref{Derivations}).
11656 @item profile-collisions
11657 Check whether installing the given packages in a profile would lead to
11658 collisions. Collisions occur when several packages with the same name
11659 but a different version or a different store file name are propagated.
11660 @xref{package Reference, @code{propagated-inputs}}, for more information
11661 on propagated inputs.
11664 @cindex Software Heritage, source code archive
11665 @cindex archival of source code, Software Heritage
11666 Checks whether the package's source code is archived at
11667 @uref{https://www.softwareheritage.org, Software Heritage}.
11669 When the source code that is not archived comes from a version-control system
11670 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
11671 ``save'' request so that it eventually archives it. This ensures that the
11672 source will remain available in the long term, and that Guix can fall back to
11673 Software Heritage should the source code disappear from its original host.
11674 The status of recent ``save'' requests can be
11675 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
11677 When source code is a tarball obtained with @code{url-fetch}, simply print a
11678 message when it is not archived. As of this writing, Software Heritage does
11679 not allow requests to save arbitrary tarballs; we are working on ways to
11680 ensure that non-VCS source code is also archived.
11683 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
11684 request rate per IP address}. When the limit is reached, @command{guix lint}
11685 prints a message and the @code{archival} checker stops doing anything until
11686 that limit has been reset.
11689 @cindex security vulnerabilities
11690 @cindex CVE, Common Vulnerabilities and Exposures
11691 Report known vulnerabilities found in the Common Vulnerabilities and
11692 Exposures (CVE) databases of the current and past year
11693 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
11696 To view information about a particular vulnerability, visit pages such as:
11700 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
11702 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
11706 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
11707 @code{CVE-2015-7554}.
11709 Package developers can specify in package recipes the
11710 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
11711 name and version of the package when they differ from the name or version
11712 that Guix uses, as in this example:
11718 ;; CPE calls this package "grub2".
11719 (properties '((cpe-name . "grub2")
11720 (cpe-version . "2.3"))))
11723 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
11724 Some entries in the CVE database do not specify which version of a
11725 package they apply to, and would thus ``stick around'' forever. Package
11726 developers who found CVE alerts and verified they can be ignored can
11727 declare them as in this example:
11733 ;; These CVEs no longer apply and can be safely ignored.
11734 (properties `((lint-hidden-cve . ("CVE-2011-0433"
11737 "CVE-2011-5244")))))
11741 Warn about obvious source code formatting issues: trailing white space,
11742 use of tabulations, etc.
11745 The general syntax is:
11748 guix lint @var{options} @var{package}@dots{}
11751 If no package is given on the command line, then all packages are checked.
11752 The @var{options} may be zero or more of the following:
11755 @item --list-checkers
11757 List and describe all the available checkers that will be run on packages
11762 Only enable the checkers specified in a comma-separated list using the
11763 names returned by @option{--list-checkers}.
11767 Only disable the checkers specified in a comma-separated list using the
11768 names returned by @option{--list-checkers}.
11772 Only enable the checkers that do not depend on Internet access.
11774 @item --load-path=@var{directory}
11775 @itemx -L @var{directory}
11776 Add @var{directory} to the front of the package module search path
11777 (@pxref{Package Modules}).
11779 This allows users to define their own packages and make them visible to
11780 the command-line tools.
11784 @node Invoking guix size
11785 @section Invoking @command{guix size}
11788 @cindex package size
11790 @cindex @command{guix size}
11791 The @command{guix size} command helps package developers profile the
11792 disk usage of packages. It is easy to overlook the impact of an
11793 additional dependency added to a package, or the impact of using a
11794 single output for a package that could easily be split (@pxref{Packages
11795 with Multiple Outputs}). Such are the typical issues that
11796 @command{guix size} can highlight.
11798 The command can be passed one or more package specifications
11799 such as @code{gcc@@4.8}
11800 or @code{guile:debug}, or a file name in the store. Consider this
11804 $ guix size coreutils
11805 store item total self
11806 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
11807 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
11808 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
11809 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
11810 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
11811 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
11812 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
11813 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
11818 The store items listed here constitute the @dfn{transitive closure} of
11819 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
11820 would be returned by:
11823 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
11826 Here the output shows three columns next to store items. The first column,
11827 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
11828 the store item---that is, its own size plus the size of all its
11829 dependencies. The next column, labeled ``self'', shows the size of the
11830 item itself. The last column shows the ratio of the size of the item
11831 itself to the space occupied by all the items listed here.
11833 In this example, we see that the closure of Coreutils weighs in at
11834 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
11835 libraries. (That libc and GCC's libraries represent a large fraction of
11836 the closure is not a problem @i{per se} because they are always available
11837 on the system anyway.)
11839 Since the command also accepts store file names, assessing the size of
11840 a build result is straightforward:
11843 guix size $(guix system build config.scm)
11846 When the package(s) passed to @command{guix size} are available in the
11847 store@footnote{More precisely, @command{guix size} looks for the
11848 @emph{ungrafted} variant of the given package(s), as returned by
11849 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
11850 for information on grafts.}, @command{guix size} queries the daemon to determine its
11851 dependencies, and measures its size in the store, similar to @command{du
11852 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
11855 When the given packages are @emph{not} in the store, @command{guix size}
11856 reports information based on the available substitutes
11857 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
11858 store items that are not even on disk, only available remotely.
11860 You can also specify several package names:
11863 $ guix size coreutils grep sed bash
11864 store item total self
11865 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
11866 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
11867 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
11868 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
11874 In this example we see that the combination of the four packages takes
11875 102.3@tie{}MiB in total, which is much less than the sum of each closure
11876 since they have a lot of dependencies in common.
11878 When looking at the profile returned by @command{guix size}, you may
11879 find yourself wondering why a given package shows up in the profile at
11880 all. To understand it, you can use @command{guix graph --path -t
11881 references} to display the shortest path between the two packages
11882 (@pxref{Invoking guix graph}).
11884 The available options are:
11888 @item --substitute-urls=@var{urls}
11889 Use substitute information from @var{urls}.
11890 @xref{client-substitute-urls, the same option for @code{guix build}}.
11892 @item --sort=@var{key}
11893 Sort lines according to @var{key}, one of the following options:
11897 the size of each item (the default);
11899 the total size of the item's closure.
11902 @item --map-file=@var{file}
11903 Write a graphical map of disk usage in PNG format to @var{file}.
11905 For the example above, the map looks like this:
11907 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
11908 produced by @command{guix size}}
11910 This option requires that
11911 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
11912 installed and visible in Guile's module search path. When that is not
11913 the case, @command{guix size} fails as it tries to load it.
11915 @item --system=@var{system}
11916 @itemx -s @var{system}
11917 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
11919 @item --load-path=@var{directory}
11920 @itemx -L @var{directory}
11921 Add @var{directory} to the front of the package module search path
11922 (@pxref{Package Modules}).
11924 This allows users to define their own packages and make them visible to
11925 the command-line tools.
11928 @node Invoking guix graph
11929 @section Invoking @command{guix graph}
11932 @cindex @command{guix graph}
11933 @cindex package dependencies
11934 Packages and their dependencies form a @dfn{graph}, specifically a
11935 directed acyclic graph (DAG). It can quickly become difficult to have a
11936 mental model of the package DAG, so the @command{guix graph} command
11937 provides a visual representation of the DAG. By default,
11938 @command{guix graph} emits a DAG representation in the input format of
11939 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
11940 directly to the @command{dot} command of Graphviz. It can also emit an
11941 HTML page with embedded JavaScript code to display a ``chord diagram''
11942 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
11943 emit Cypher queries to construct a graph in a graph database supporting
11944 the @uref{https://www.opencypher.org/, openCypher} query language. With
11945 @option{--path}, it simply displays the shortest path between two
11946 packages. The general syntax is:
11949 guix graph @var{options} @var{package}@dots{}
11952 For example, the following command generates a PDF file representing the
11953 package DAG for the GNU@tie{}Core Utilities, showing its build-time
11957 guix graph coreutils | dot -Tpdf > dag.pdf
11960 The output looks like this:
11962 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
11964 Nice little graph, no?
11966 You may find it more pleasant to navigate the graph interactively with
11967 @command{xdot} (from the @code{xdot} package):
11970 guix graph coreutils | xdot -
11973 But there is more than one graph! The one above is concise: it is the
11974 graph of package objects, omitting implicit inputs such as GCC, libc,
11975 grep, etc. It is often useful to have such a concise graph, but
11976 sometimes one may want to see more details. @command{guix graph} supports
11977 several types of graphs, allowing you to choose the level of detail:
11981 This is the default type used in the example above. It shows the DAG of
11982 package objects, excluding implicit dependencies. It is concise, but
11983 filters out many details.
11985 @item reverse-package
11986 This shows the @emph{reverse} DAG of packages. For example:
11989 guix graph --type=reverse-package ocaml
11992 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
11993 you are also interested in cases where OCaml is an implicit dependency, see
11994 @code{reverse-bag} below).
11996 Note that for core packages this can yield huge graphs. If all you want
11997 is to know the number of packages that depend on a given package, use
11998 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
11999 @option{--list-dependent}}).
12002 This is the package DAG, @emph{including} implicit inputs.
12004 For instance, the following command:
12007 guix graph --type=bag-emerged coreutils
12010 ...@: yields this bigger graph:
12012 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
12014 At the bottom of the graph, we see all the implicit inputs of
12015 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
12017 Now, note that the dependencies of these implicit inputs---that is, the
12018 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
12019 here, for conciseness.
12022 Similar to @code{bag-emerged}, but this time including all the bootstrap
12025 @item bag-with-origins
12026 Similar to @code{bag}, but also showing origins and their dependencies.
12029 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
12030 it also takes implicit dependencies into account. For example:
12033 guix graph -t reverse-bag dune
12037 ...@: yields the graph of all packages that depend on Dune, directly or
12038 indirectly. Since Dune is an @emph{implicit} dependency of many packages
12039 @i{via} @code{dune-build-system}, this shows a large number of packages,
12040 whereas @code{reverse-package} would show very few if any.
12043 This is the most detailed representation: It shows the DAG of
12044 derivations (@pxref{Derivations}) and plain store items. Compared to
12045 the above representation, many additional nodes are visible, including
12046 build scripts, patches, Guile modules, etc.
12048 For this type of graph, it is also possible to pass a @file{.drv} file
12049 name instead of a package name, as in:
12052 guix graph -t derivation `guix system build -d my-config.scm`
12056 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
12057 For example, the following command shows the graph for the package
12058 module that defines the @code{guile} package:
12061 guix graph -t module guile | xdot -
12065 All the types above correspond to @emph{build-time dependencies}. The
12066 following graph type represents the @emph{run-time dependencies}:
12070 This is the graph of @dfn{references} of a package output, as returned
12071 by @command{guix gc --references} (@pxref{Invoking guix gc}).
12073 If the given package output is not available in the store, @command{guix
12074 graph} attempts to obtain dependency information from substitutes.
12076 Here you can also pass a store file name instead of a package name. For
12077 example, the command below produces the reference graph of your profile
12078 (which can be big!):
12081 guix graph -t references `readlink -f ~/.guix-profile`
12085 This is the graph of the @dfn{referrers} of a store item, as returned by
12086 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
12088 This relies exclusively on local information from your store. For
12089 instance, let us suppose that the current Inkscape is available in 10
12090 profiles on your machine; @command{guix graph -t referrers inkscape}
12091 will show a graph rooted at Inkscape and with those 10 profiles linked
12094 It can help determine what is preventing a store item from being garbage
12099 @cindex shortest path, between packages
12100 Often, the graph of the package you are interested in does not fit on
12101 your screen, and anyway all you want to know is @emph{why} that package
12102 actually depends on some seemingly unrelated package. The
12103 @option{--path} option instructs @command{guix graph} to display the
12104 shortest path between two packages (or derivations, or store items,
12108 $ guix graph --path emacs libunistring
12111 libunistring@@0.9.10
12112 $ guix graph --path -t derivation emacs libunistring
12113 /gnu/store/@dots{}-emacs-26.3.drv
12114 /gnu/store/@dots{}-mailutils-3.9.drv
12115 /gnu/store/@dots{}-libunistring-0.9.10.drv
12116 $ guix graph --path -t references emacs libunistring
12117 /gnu/store/@dots{}-emacs-26.3
12118 /gnu/store/@dots{}-libidn2-2.2.0
12119 /gnu/store/@dots{}-libunistring-0.9.10
12122 The available options are the following:
12125 @item --type=@var{type}
12126 @itemx -t @var{type}
12127 Produce a graph output of @var{type}, where @var{type} must be one of
12128 the values listed above.
12131 List the supported graph types.
12133 @item --backend=@var{backend}
12134 @itemx -b @var{backend}
12135 Produce a graph using the selected @var{backend}.
12137 @item --list-backends
12138 List the supported graph backends.
12140 Currently, the available backends are Graphviz and d3.js.
12143 Display the shortest path between two nodes of the type specified by
12144 @option{--type}. The example below shows the shortest path between
12145 @code{libreoffice} and @code{llvm} according to the references of
12146 @code{libreoffice}:
12149 $ guix graph --path -t references libreoffice llvm
12150 /gnu/store/@dots{}-libreoffice-6.4.2.2
12151 /gnu/store/@dots{}-libepoxy-1.5.4
12152 /gnu/store/@dots{}-mesa-19.3.4
12153 /gnu/store/@dots{}-llvm-9.0.1
12156 @item --expression=@var{expr}
12157 @itemx -e @var{expr}
12158 Consider the package @var{expr} evaluates to.
12160 This is useful to precisely refer to a package, as in this example:
12163 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
12166 @item --system=@var{system}
12167 @itemx -s @var{system}
12168 Display the graph for @var{system}---e.g., @code{i686-linux}.
12170 The package dependency graph is largely architecture-independent, but there
12171 are some architecture-dependent bits that this option allows you to visualize.
12173 @item --load-path=@var{directory}
12174 @itemx -L @var{directory}
12175 Add @var{directory} to the front of the package module search path
12176 (@pxref{Package Modules}).
12178 This allows users to define their own packages and make them visible to
12179 the command-line tools.
12182 On top of that, @command{guix graph} supports all the usual package
12183 transformation options (@pxref{Package Transformation Options}). This
12184 makes it easy to view the effect of a graph-rewriting transformation
12185 such as @option{--with-input}. For example, the command below outputs
12186 the graph of @code{git} once @code{openssl} has been replaced by
12187 @code{libressl} everywhere in the graph:
12190 guix graph git --with-input=openssl=libressl
12193 So many possibilities, so much fun!
12195 @node Invoking guix publish
12196 @section Invoking @command{guix publish}
12198 @cindex @command{guix publish}
12199 The purpose of @command{guix publish} is to enable users to easily share
12200 their store with others, who can then use it as a substitute server
12201 (@pxref{Substitutes}).
12203 When @command{guix publish} runs, it spawns an HTTP server which allows
12204 anyone with network access to obtain substitutes from it. This means
12205 that any machine running Guix can also act as if it were a build farm,
12206 since the HTTP interface is compatible with Cuirass, the software behind
12207 the @code{@value{SUBSTITUTE-SERVER}} build farm.
12209 For security, each substitute is signed, allowing recipients to check
12210 their authenticity and integrity (@pxref{Substitutes}). Because
12211 @command{guix publish} uses the signing key of the system, which is only
12212 readable by the system administrator, it must be started as root; the
12213 @option{--user} option makes it drop root privileges early on.
12215 The signing key pair must be generated before @command{guix publish} is
12216 launched, using @command{guix archive --generate-key} (@pxref{Invoking
12219 When the @option{--advertise} option is passed, the server advertises
12220 its availability on the local network using multicast DNS (mDNS) and DNS
12221 service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
12222 guile-avahi, Using Avahi in Guile Scheme Programs}).
12224 The general syntax is:
12227 guix publish @var{options}@dots{}
12230 Running @command{guix publish} without any additional arguments will
12231 spawn an HTTP server on port 8080:
12237 Once a publishing server has been authorized, the daemon may download
12238 substitutes from it. @xref{Getting Substitutes from Other Servers}.
12240 By default, @command{guix publish} compresses archives on the fly as it
12241 serves them. This ``on-the-fly'' mode is convenient in that it requires
12242 no setup and is immediately available. However, when serving lots of
12243 clients, we recommend using the @option{--cache} option, which enables
12244 caching of the archives before they are sent to clients---see below for
12245 details. The @command{guix weather} command provides a handy way to
12246 check what a server provides (@pxref{Invoking guix weather}).
12248 As a bonus, @command{guix publish} also serves as a content-addressed
12249 mirror for source files referenced in @code{origin} records
12250 (@pxref{origin Reference}). For instance, assuming @command{guix
12251 publish} is running on @code{example.org}, the following URL returns the
12252 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
12253 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
12256 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
12259 Obviously, these URLs only work for files that are in the store; in
12260 other cases, they return 404 (``Not Found'').
12262 @cindex build logs, publication
12263 Build logs are available from @code{/log} URLs like:
12266 http://example.org/log/gwspk@dots{}-guile-2.2.3
12270 When @command{guix-daemon} is configured to save compressed build logs,
12271 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
12272 URLs return the compressed log as-is, with an appropriate
12273 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
12274 running @command{guix-daemon} with @option{--log-compression=gzip} since
12275 Web browsers can automatically decompress it, which is not the case with
12278 The following options are available:
12281 @item --port=@var{port}
12282 @itemx -p @var{port}
12283 Listen for HTTP requests on @var{port}.
12285 @item --listen=@var{host}
12286 Listen on the network interface for @var{host}. The default is to
12287 accept connections from any interface.
12289 @item --user=@var{user}
12290 @itemx -u @var{user}
12291 Change privileges to @var{user} as soon as possible---i.e., once the
12292 server socket is open and the signing key has been read.
12294 @item --compression[=@var{method}[:@var{level}]]
12295 @itemx -C [@var{method}[:@var{level}]]
12296 Compress data using the given @var{method} and @var{level}. @var{method} is
12297 one of @code{lzip} and @code{gzip}; when @var{method} is omitted, @code{gzip}
12300 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
12301 to different compression levels: 1 is the fastest, and 9 is the best
12302 (CPU-intensive). The default is 3.
12304 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a small
12305 increase in CPU usage; see
12306 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip Web
12309 Unless @option{--cache} is used, compression occurs on the fly and
12310 the compressed streams are not
12311 cached. Thus, to reduce load on the machine that runs @command{guix
12312 publish}, it may be a good idea to choose a low compression level, to
12313 run @command{guix publish} behind a caching proxy, or to use
12314 @option{--cache}. Using @option{--cache} has the advantage that it
12315 allows @command{guix publish} to add @code{Content-Length} HTTP header
12318 This option can be repeated, in which case every substitute gets compressed
12319 using all the selected methods, and all of them are advertised. This is
12320 useful when users may not support all the compression methods: they can select
12321 the one they support.
12323 @item --cache=@var{directory}
12324 @itemx -c @var{directory}
12325 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
12326 and only serve archives that are in cache.
12328 When this option is omitted, archives and meta-data are created
12329 on-the-fly. This can reduce the available bandwidth, especially when
12330 compression is enabled, since this may become CPU-bound. Another
12331 drawback of the default mode is that the length of archives is not known
12332 in advance, so @command{guix publish} does not add a
12333 @code{Content-Length} HTTP header to its responses, which in turn
12334 prevents clients from knowing the amount of data being downloaded.
12336 Conversely, when @option{--cache} is used, the first request for a store
12337 item (@i{via} a @code{.narinfo} URL) triggers a
12338 background process to @dfn{bake} the archive---computing its
12339 @code{.narinfo} and compressing the archive, if needed. Once the
12340 archive is cached in @var{directory}, subsequent requests succeed and
12341 are served directly from the cache, which guarantees that clients get
12342 the best possible bandwidth.
12344 That first @code{.narinfo} request nonetheless returns 200, provided the
12345 requested store item is ``small enough'', below the cache bypass
12346 threshold---see @option{--cache-bypass-threshold} below. That way,
12347 clients do not have to wait until the archive is baked. For larger
12348 store items, the first @code{.narinfo} request returns 404, meaning that
12349 clients have to wait until the archive is baked.
12351 The ``baking'' process is performed by worker threads. By default, one
12352 thread per CPU core is created, but this can be customized. See
12353 @option{--workers} below.
12355 When @option{--ttl} is used, cached entries are automatically deleted
12356 when they have expired.
12358 @item --workers=@var{N}
12359 When @option{--cache} is used, request the allocation of @var{N} worker
12360 threads to ``bake'' archives.
12362 @item --ttl=@var{ttl}
12363 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
12364 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
12365 days, @code{1m} means 1 month, and so on.
12367 This allows the user's Guix to keep substitute information in cache for
12368 @var{ttl}. However, note that @code{guix publish} does not itself
12369 guarantee that the store items it provides will indeed remain available
12370 for as long as @var{ttl}.
12372 Additionally, when @option{--cache} is used, cached entries that have
12373 not been accessed for @var{ttl} and that no longer have a corresponding
12374 item in the store, may be deleted.
12376 @item --cache-bypass-threshold=@var{size}
12377 When used in conjunction with @option{--cache}, store items smaller than
12378 @var{size} are immediately available, even when they are not yet in
12379 cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
12380 for megabytes and so on. The default is @code{10M}.
12382 ``Cache bypass'' allows you to reduce the publication delay for clients
12383 at the expense of possibly additional I/O and CPU use on the server
12384 side: depending on the client access patterns, those store items can end
12385 up being baked several times until a copy is available in cache.
12387 Increasing the threshold may be useful for sites that have few users, or
12388 to guarantee that users get substitutes even for store items that are
12391 @item --nar-path=@var{path}
12392 Use @var{path} as the prefix for the URLs of ``nar'' files
12393 (@pxref{Invoking guix archive, normalized archives}).
12395 By default, nars are served at a URL such as
12396 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
12397 change the @code{/nar} part to @var{path}.
12399 @item --public-key=@var{file}
12400 @itemx --private-key=@var{file}
12401 Use the specific @var{file}s as the public/private key pair used to sign
12402 the store items being published.
12404 The files must correspond to the same key pair (the private key is used
12405 for signing and the public key is merely advertised in the signature
12406 metadata). They must contain keys in the canonical s-expression format
12407 as produced by @command{guix archive --generate-key} (@pxref{Invoking
12408 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
12409 @file{/etc/guix/signing-key.sec} are used.
12411 @item --repl[=@var{port}]
12412 @itemx -r [@var{port}]
12413 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
12414 Reference Manual}) on @var{port} (37146 by default). This is used
12415 primarily for debugging a running @command{guix publish} server.
12418 Enabling @command{guix publish} on Guix System is a one-liner: just
12419 instantiate a @code{guix-publish-service-type} service in the @code{services} field
12420 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
12421 @code{guix-publish-service-type}}).
12423 If you are instead running Guix on a ``foreign distro'', follow these
12428 If your host distro uses the systemd init system:
12431 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
12432 /etc/systemd/system/
12433 # systemctl start guix-publish && systemctl enable guix-publish
12437 If your host distro uses the Upstart init system:
12440 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
12441 # start guix-publish
12445 Otherwise, proceed similarly with your distro's init system.
12448 @node Invoking guix challenge
12449 @section Invoking @command{guix challenge}
12451 @cindex reproducible builds
12452 @cindex verifiable builds
12453 @cindex @command{guix challenge}
12455 Do the binaries provided by this server really correspond to the source
12456 code it claims to build? Is a package build process deterministic?
12457 These are the questions the @command{guix challenge} command attempts to
12460 The former is obviously an important question: Before using a substitute
12461 server (@pxref{Substitutes}), one had better @emph{verify} that it
12462 provides the right binaries, and thus @emph{challenge} it. The latter
12463 is what enables the former: If package builds are deterministic, then
12464 independent builds of the package should yield the exact same result,
12465 bit for bit; if a server provides a binary different from the one
12466 obtained locally, it may be either corrupt or malicious.
12468 We know that the hash that shows up in @file{/gnu/store} file names is
12469 the hash of all the inputs of the process that built the file or
12470 directory---compilers, libraries, build scripts,
12471 etc. (@pxref{Introduction}). Assuming deterministic build processes,
12472 one store file name should map to exactly one build output.
12473 @command{guix challenge} checks whether there is, indeed, a single
12474 mapping by comparing the build outputs of several independent builds of
12475 any given store item.
12477 The command output looks like this:
12480 $ guix challenge --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
12481 updating list of substitutes from 'https://@value{SUBSTITUTE-SERVER}'... 100.0%
12482 updating list of substitutes from 'https://guix.example.org'... 100.0%
12483 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
12484 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
12485 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
12486 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
12488 /lib/libcrypto.so.1.1
12491 /gnu/store/@dots{}-git-2.5.0 contents differ:
12492 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
12493 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
12494 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
12496 /libexec/git-core/git-fsck
12498 /gnu/store/@dots{}-pius-2.1.1 contents differ:
12499 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
12500 https://@value{SUBSTITUTE-SERVER}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
12501 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
12503 /share/man/man1/pius.1.gz
12507 6,406 store items were analyzed:
12508 - 4,749 (74.1%) were identical
12509 - 525 (8.2%) differed
12510 - 1,132 (17.7%) were inconclusive
12514 In this example, @command{guix challenge} first scans the store to
12515 determine the set of locally-built derivations---as opposed to store
12516 items that were downloaded from a substitute server---and then queries
12517 all the substitute servers. It then reports those store items for which
12518 the servers obtained a result different from the local build.
12520 @cindex non-determinism, in package builds
12521 As an example, @code{guix.example.org} always gets a different answer.
12522 Conversely, @code{@value{SUBSTITUTE-SERVER}} agrees with local builds, except in the
12523 case of Git. This might indicate that the build process of Git is
12524 non-deterministic, meaning that its output varies as a function of
12525 various things that Guix does not fully control, in spite of building
12526 packages in isolated environments (@pxref{Features}). Most common
12527 sources of non-determinism include the addition of timestamps in build
12528 results, the inclusion of random numbers, and directory listings sorted
12529 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
12532 To find out what is wrong with this Git binary, the easiest approach is
12536 guix challenge git \
12537 --diff=diffoscope \
12538 --substitute-urls="https://@value{SUBSTITUTE-SERVER} https://guix.example.org"
12541 This automatically invokes @command{diffoscope}, which displays detailed
12542 information about files that differ.
12544 Alternatively, we can do something along these lines (@pxref{Invoking guix
12548 $ wget -q -O - https://@value{SUBSTITUTE-SERVER}/nar/lzip/@dots{}-git-2.5.0 \
12549 | lzip -d | guix archive -x /tmp/git
12550 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
12553 This command shows the difference between the files resulting from the
12554 local build, and the files resulting from the build on
12555 @code{@value{SUBSTITUTE-SERVER}} (@pxref{Overview, Comparing and Merging Files,,
12556 diffutils, Comparing and Merging Files}). The @command{diff} command
12557 works great for text files. When binary files differ, a better option
12558 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
12559 visualize differences for all kinds of files.
12561 Once you have done that work, you can tell whether the differences are due
12562 to a non-deterministic build process or to a malicious server. We try
12563 hard to remove sources of non-determinism in packages to make it easier
12564 to verify substitutes, but of course, this is a process that
12565 involves not just Guix, but a large part of the free software community.
12566 In the meantime, @command{guix challenge} is one tool to help address
12569 If you are writing packages for Guix, you are encouraged to check
12570 whether @code{@value{SUBSTITUTE-SERVER}} and other substitute servers obtain the
12571 same build result as you did with:
12574 $ guix challenge @var{package}
12578 where @var{package} is a package specification such as
12579 @code{guile@@2.0} or @code{glibc:debug}.
12581 The general syntax is:
12584 guix challenge @var{options} [@var{packages}@dots{}]
12587 When a difference is found between the hash of a locally-built item and
12588 that of a server-provided substitute, or among substitutes provided by
12589 different servers, the command displays it as in the example above and
12590 its exit code is 2 (other non-zero exit codes denote other kinds of
12593 The one option that matters is:
12597 @item --substitute-urls=@var{urls}
12598 Consider @var{urls} the whitespace-separated list of substitute source
12599 URLs to compare to.
12601 @item --diff=@var{mode}
12602 Upon mismatches, show differences according to @var{mode}, one of:
12605 @item @code{simple} (the default)
12606 Show the list of files that differ.
12608 @item @code{diffoscope}
12609 @itemx @var{command}
12610 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
12611 two directories whose contents do not match.
12613 When @var{command} is an absolute file name, run @var{command} instead
12617 Do not show further details about the differences.
12620 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
12621 downloads the store items from the given substitute servers so that it
12626 Show details about matches (identical contents) in addition to
12627 information about mismatches.
12631 @node Invoking guix copy
12632 @section Invoking @command{guix copy}
12634 @cindex copy, of store items, over SSH
12635 @cindex SSH, copy of store items
12636 @cindex sharing store items across machines
12637 @cindex transferring store items across machines
12638 The @command{guix copy} command copies items from the store of one
12639 machine to that of another machine over a secure shell (SSH)
12640 connection@footnote{This command is available only when Guile-SSH was
12641 found. @xref{Requirements}, for details.}. For example, the following
12642 command copies the @code{coreutils} package, the user's profile, and all
12643 their dependencies over to @var{host}, logged in as @var{user}:
12646 guix copy --to=@var{user}@@@var{host} \
12647 coreutils `readlink -f ~/.guix-profile`
12650 If some of the items to be copied are already present on @var{host},
12651 they are not actually sent.
12653 The command below retrieves @code{libreoffice} and @code{gimp} from
12654 @var{host}, assuming they are available there:
12657 guix copy --from=@var{host} libreoffice gimp
12660 The SSH connection is established using the Guile-SSH client, which is
12661 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
12662 @file{~/.ssh/config}, and uses the SSH agent for authentication.
12664 The key used to sign items that are sent must be accepted by the remote
12665 machine. Likewise, the key used by the remote machine to sign items you
12666 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
12667 own daemon. @xref{Invoking guix archive}, for more information about
12668 store item authentication.
12670 The general syntax is:
12673 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
12676 You must always specify one of the following options:
12679 @item --to=@var{spec}
12680 @itemx --from=@var{spec}
12681 Specify the host to send to or receive from. @var{spec} must be an SSH
12682 spec such as @code{example.org}, @code{charlie@@example.org}, or
12683 @code{charlie@@example.org:2222}.
12686 The @var{items} can be either package names, such as @code{gimp}, or
12687 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
12689 When specifying the name of a package to send, it is first built if
12690 needed, unless @option{--dry-run} was specified. Common build options
12691 are supported (@pxref{Common Build Options}).
12694 @node Invoking guix container
12695 @section Invoking @command{guix container}
12697 @cindex @command{guix container}
12699 As of version @value{VERSION}, this tool is experimental. The interface
12700 is subject to radical change in the future.
12703 The purpose of @command{guix container} is to manipulate processes
12704 running within an isolated environment, commonly known as a
12705 ``container'', typically created by the @command{guix environment}
12706 (@pxref{Invoking guix environment}) and @command{guix system container}
12707 (@pxref{Invoking guix system}) commands.
12709 The general syntax is:
12712 guix container @var{action} @var{options}@dots{}
12715 @var{action} specifies the operation to perform with a container, and
12716 @var{options} specifies the context-specific arguments for the action.
12718 The following actions are available:
12722 Execute a command within the context of a running container.
12727 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
12730 @var{pid} specifies the process ID of the running container.
12731 @var{program} specifies an executable file name within the root file
12732 system of the container. @var{arguments} are the additional options that
12733 will be passed to @var{program}.
12735 The following command launches an interactive login shell inside a
12736 Guix system container, started by @command{guix system container}, and whose
12737 process ID is 9001:
12740 guix container exec 9001 /run/current-system/profile/bin/bash --login
12743 Note that the @var{pid} cannot be the parent process of a container. It
12744 must be PID 1 of the container or one of its child processes.
12748 @node Invoking guix weather
12749 @section Invoking @command{guix weather}
12751 Occasionally you're grumpy because substitutes are lacking and you end
12752 up building packages by yourself (@pxref{Substitutes}). The
12753 @command{guix weather} command reports on substitute availability on the
12754 specified servers so you can have an idea of whether you'll be grumpy
12755 today. It can sometimes be useful info as a user, but it is primarily
12756 useful to people running @command{guix publish} (@pxref{Invoking guix
12759 @cindex statistics, for substitutes
12760 @cindex availability of substitutes
12761 @cindex substitute availability
12762 @cindex weather, substitute availability
12763 Here's a sample run:
12766 $ guix weather --substitute-urls=https://guix.example.org
12767 computing 5,872 package derivations for x86_64-linux...
12768 looking for 6,128 store items on https://guix.example.org..
12769 updating list of substitutes from 'https://guix.example.org'... 100.0%
12770 https://guix.example.org
12771 43.4% substitutes available (2,658 out of 6,128)
12772 7,032.5 MiB of nars (compressed)
12773 19,824.2 MiB on disk (uncompressed)
12774 0.030 seconds per request (182.9 seconds in total)
12775 33.5 requests per second
12777 9.8% (342 out of 3,470) of the missing items are queued
12779 x86_64-linux: 518 (59.7%)
12780 i686-linux: 221 (25.5%)
12781 aarch64-linux: 128 (14.8%)
12782 build rate: 23.41 builds per hour
12783 x86_64-linux: 11.16 builds per hour
12784 i686-linux: 6.03 builds per hour
12785 aarch64-linux: 6.41 builds per hour
12788 @cindex continuous integration, statistics
12789 As you can see, it reports the fraction of all the packages for which
12790 substitutes are available on the server---regardless of whether
12791 substitutes are enabled, and regardless of whether this server's signing
12792 key is authorized. It also reports the size of the compressed archives
12793 (``nars'') provided by the server, the size the corresponding store
12794 items occupy in the store (assuming deduplication is turned off), and
12795 the server's throughput. The second part gives continuous integration
12796 (CI) statistics, if the server supports it. In addition, using the
12797 @option{--coverage} option, @command{guix weather} can list ``important''
12798 package substitutes missing on the server (see below).
12800 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
12801 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
12802 challenge}, it ignores signatures on those substitutes, which is
12803 innocuous since the command only gathers statistics and cannot install
12806 The general syntax is:
12809 guix weather @var{options}@dots{} [@var{packages}@dots{}]
12812 When @var{packages} is omitted, @command{guix weather} checks the availability
12813 of substitutes for @emph{all} the packages, or for those specified with
12814 @option{--manifest}; otherwise it only considers the specified packages. It
12815 is also possible to query specific system types with @option{--system}.
12816 @command{guix weather} exits with a non-zero code when the fraction of
12817 available substitutes is below 100%.
12819 The available options are listed below.
12822 @item --substitute-urls=@var{urls}
12823 @var{urls} is the space-separated list of substitute server URLs to
12824 query. When this option is omitted, the default set of substitute
12825 servers is queried.
12827 @item --system=@var{system}
12828 @itemx -s @var{system}
12829 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
12830 option can be repeated, in which case @command{guix weather} will query
12831 substitutes for several system types.
12833 @item --manifest=@var{file}
12834 Instead of querying substitutes for all the packages, only ask for those
12835 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
12836 with the @code{-m} option of @command{guix package} (@pxref{Invoking
12839 This option can be repeated several times, in which case the manifests
12842 @item --coverage[=@var{count}]
12843 @itemx -c [@var{count}]
12844 Report on substitute coverage for packages: list packages with at least
12845 @var{count} dependents (zero by default) for which substitutes are
12846 unavailable. Dependent packages themselves are not listed: if @var{b} depends
12847 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
12848 @var{b} usually lacks substitutes as well. The result looks like this:
12851 $ guix weather --substitute-urls=@value{SUBSTITUTE-URL} -c 10
12852 computing 8,983 package derivations for x86_64-linux...
12853 looking for 9,343 store items on @value{SUBSTITUTE-URL}...
12854 updating substitutes from '@value{SUBSTITUTE-URL}'... 100.0%
12855 @value{SUBSTITUTE-URL}
12856 64.7% substitutes available (6,047 out of 9,343)
12858 2502 packages are missing from '@value{SUBSTITUTE-URL}' for 'x86_64-linux', among which:
12859 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
12860 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
12861 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
12865 What this example shows is that @code{kcoreaddons} and presumably the 58
12866 packages that depend on it have no substitutes at @code{ci.guix.info};
12867 likewise for @code{qgpgme} and the 46 packages that depend on it.
12869 If you are a Guix developer, or if you are taking care of this build farm,
12870 you'll probably want to have a closer look at these packages: they may simply
12873 @item --display-missing
12874 Display the list of store items for which substitutes are missing.
12877 @node Invoking guix processes
12878 @section Invoking @command{guix processes}
12880 The @command{guix processes} command can be useful to developers and system
12881 administrators, especially on multi-user machines and on build farms: it lists
12882 the current sessions (connections to the daemon), as well as information about
12883 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
12884 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
12885 listed.}. Here's an example of the information it returns:
12888 $ sudo guix processes
12891 ClientCommand: guix environment --ad-hoc python
12895 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
12899 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
12900 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
12901 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
12902 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
12904 ChildCommand: guix offload x86_64-linux 7200 1 28800
12906 ChildCommand: guix offload x86_64-linux 7200 1 28800
12908 ChildCommand: guix offload x86_64-linux 7200 1 28800
12911 In this example we see that @command{guix-daemon} has three clients:
12912 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
12913 integration tool; their process identifier (PID) is given by the
12914 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
12915 @command{guix-daemon} sub-process of this particular session.
12917 The @code{LockHeld} fields show which store items are currently locked
12918 by this session, which corresponds to store items being built or
12919 substituted (the @code{LockHeld} field is not displayed when
12920 @command{guix processes} is not running as root). Last, by looking at
12921 the @code{ChildPID} and @code{ChildCommand} fields, we understand that
12922 these three builds are being offloaded (@pxref{Daemon Offload Setup}).
12924 The output is in Recutils format so we can use the handy @command{recsel}
12925 command to select sessions of interest (@pxref{Selection Expressions,,,
12926 recutils, GNU recutils manual}). As an example, the command shows the command
12927 line and PID of the client that triggered the build of a Perl package:
12930 $ sudo guix processes | \
12931 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
12933 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
12936 Additional options are listed below.
12939 @item --format=@var{format}
12940 @itemx -f @var{format}
12941 Produce output in the specified @var{format}, one of:
12945 The default option. It outputs a set of Session recutils records
12946 that include each @code{ChildProcess} as a field.
12949 Normalize the output records into record sets (@pxref{Record Sets,,,
12950 recutils, GNU recutils manual}). Normalizing into record sets allows
12951 joins across record types. The example below lists the PID of each
12952 @code{ChildProcess} and the associated PID for @code{Session} that
12953 spawned the @code{ChildProcess} where the @code{Session} was started
12954 using @command{guix build}.
12957 $ guix processes --format=normalized | \
12961 -p Session.PID,PID \
12962 -e 'Session.ClientCommand ~ "guix build"'
12975 @node System Configuration
12976 @chapter System Configuration
12978 @cindex system configuration
12979 Guix System supports a consistent whole-system configuration
12980 mechanism. By that we mean that all aspects of the global system
12981 configuration---such as the available system services, timezone and
12982 locale settings, user accounts---are declared in a single place. Such
12983 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
12985 One of the advantages of putting all the system configuration under the
12986 control of Guix is that it supports transactional system upgrades, and
12987 makes it possible to roll back to a previous system instantiation,
12988 should something go wrong with the new one (@pxref{Features}). Another
12989 advantage is that it makes it easy to replicate the exact same configuration
12990 across different machines, or at different points in time, without
12991 having to resort to additional administration tools layered on top of
12992 the own tools of the system.
12993 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
12995 This section describes this mechanism. First we focus on the system
12996 administrator's viewpoint---explaining how the system is configured and
12997 instantiated. Then we show how this mechanism can be extended, for
12998 instance to support new system services.
13001 * Using the Configuration System:: Customizing your GNU system.
13002 * operating-system Reference:: Detail of operating-system declarations.
13003 * File Systems:: Configuring file system mounts.
13004 * Mapped Devices:: Block device extra processing.
13005 * User Accounts:: Specifying user accounts.
13006 * Keyboard Layout:: How the system interprets key strokes.
13007 * Locales:: Language and cultural convention settings.
13008 * Services:: Specifying system services.
13009 * Setuid Programs:: Programs running with root privileges.
13010 * X.509 Certificates:: Authenticating HTTPS servers.
13011 * Name Service Switch:: Configuring libc's name service switch.
13012 * Initial RAM Disk:: Linux-Libre bootstrapping.
13013 * Bootloader Configuration:: Configuring the boot loader.
13014 * Invoking guix system:: Instantiating a system configuration.
13015 * Invoking guix deploy:: Deploying a system configuration to a remote host.
13016 * Running Guix in a VM:: How to run Guix System in a virtual machine.
13017 * Defining Services:: Adding new service definitions.
13020 @node Using the Configuration System
13021 @section Using the Configuration System
13023 The operating system is configured by providing an
13024 @code{operating-system} declaration in a file that can then be passed to
13025 the @command{guix system} command (@pxref{Invoking guix system}). A
13026 simple setup, with the default system services, the default Linux-Libre
13027 kernel, initial RAM disk, and boot loader looks like this:
13029 @findex operating-system
13031 @include os-config-bare-bones.texi
13034 This example should be self-describing. Some of the fields defined
13035 above, such as @code{host-name} and @code{bootloader}, are mandatory.
13036 Others, such as @code{packages} and @code{services}, can be omitted, in
13037 which case they get a default value.
13039 Below we discuss the effect of some of the most important fields
13040 (@pxref{operating-system Reference}, for details about all the available
13041 fields), and how to @dfn{instantiate} the operating system using
13042 @command{guix system}.
13044 @unnumberedsubsec Bootloader
13046 @cindex legacy boot, on Intel machines
13047 @cindex BIOS boot, on Intel machines
13050 The @code{bootloader} field describes the method that will be used to boot
13051 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
13052 mode, as in the example above. However, more recent machines rely instead on
13053 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
13054 the @code{bootloader} field should contain something along these lines:
13057 (bootloader-configuration
13058 (bootloader grub-efi-bootloader)
13059 (target "/boot/efi"))
13062 @xref{Bootloader Configuration}, for more information on the available
13063 configuration options.
13065 @unnumberedsubsec Globally-Visible Packages
13067 @vindex %base-packages
13068 The @code{packages} field lists packages that will be globally visible
13069 on the system, for all user accounts---i.e., in every user's @env{PATH}
13070 environment variable---in addition to the per-user profiles
13071 (@pxref{Invoking guix package}). The @code{%base-packages} variable
13072 provides all the tools one would expect for basic user and administrator
13073 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
13074 the GNU Zile lightweight text editor, @command{find}, @command{grep},
13075 etc. The example above adds GNU@tie{}Screen to those,
13076 taken from the @code{(gnu packages screen)}
13077 module (@pxref{Package Modules}). The
13078 @code{(list package output)} syntax can be used to add a specific output
13082 (use-modules (gnu packages))
13083 (use-modules (gnu packages dns))
13087 (packages (cons (list bind "utils")
13091 @findex specification->package
13092 Referring to packages by variable name, like @code{bind} above, has
13093 the advantage of being unambiguous; it also allows typos and such to be
13094 diagnosed right away as ``unbound variables''. The downside is that one
13095 needs to know which module defines which package, and to augment the
13096 @code{use-package-modules} line accordingly. To avoid that, one can use
13097 the @code{specification->package} procedure of the @code{(gnu packages)}
13098 module, which returns the best package for a given name or name and
13102 (use-modules (gnu packages))
13106 (packages (append (map specification->package
13107 '("tcpdump" "htop" "gnupg@@2.0"))
13111 @unnumberedsubsec System Services
13114 @vindex %base-services
13115 The @code{services} field lists @dfn{system services} to be made
13116 available when the system starts (@pxref{Services}).
13117 The @code{operating-system} declaration above specifies that, in
13118 addition to the basic services, we want the OpenSSH secure shell
13119 daemon listening on port 2222 (@pxref{Networking Services,
13120 @code{openssh-service-type}}). Under the hood,
13121 @code{openssh-service-type} arranges so that @command{sshd} is started with the
13122 right command-line options, possibly with supporting configuration files
13123 generated as needed (@pxref{Defining Services}).
13125 @cindex customization, of services
13126 @findex modify-services
13127 Occasionally, instead of using the base services as is, you will want to
13128 customize them. To do this, use @code{modify-services} (@pxref{Service
13129 Reference, @code{modify-services}}) to modify the list.
13131 For example, suppose you want to modify @code{guix-daemon} and Mingetty
13132 (the console log-in) in the @code{%base-services} list (@pxref{Base
13133 Services, @code{%base-services}}). To do that, you can write the
13134 following in your operating system declaration:
13137 (define %my-services
13138 ;; My very own list of services.
13139 (modify-services %base-services
13140 (guix-service-type config =>
13141 (guix-configuration
13143 ;; Fetch substitutes from example.org.
13145 (list "https://example.org/guix"
13146 "https://ci.guix.gnu.org"))))
13147 (mingetty-service-type config =>
13148 (mingetty-configuration
13150 ;; Automatially log in as "guest".
13151 (auto-login "guest")))))
13155 (services %my-services))
13158 This changes the configuration---i.e., the service parameters---of the
13159 @code{guix-service-type} instance, and that of all the
13160 @code{mingetty-service-type} instances in the @code{%base-services} list.
13161 Observe how this is accomplished: first, we arrange for the original
13162 configuration to be bound to the identifier @code{config} in the
13163 @var{body}, and then we write the @var{body} so that it evaluates to the
13164 desired configuration. In particular, notice how we use @code{inherit}
13165 to create a new configuration which has the same values as the old
13166 configuration, but with a few modifications.
13168 @cindex encrypted disk
13169 The configuration for a typical ``desktop'' usage, with an encrypted
13170 root partition, the X11 display
13171 server, GNOME and Xfce (users can choose which of these desktop
13172 environments to use at the log-in screen by pressing @kbd{F1}), network
13173 management, power management, and more, would look like this:
13176 @include os-config-desktop.texi
13179 A graphical system with a choice of lightweight window managers
13180 instead of full-blown desktop environments would look like this:
13183 @include os-config-lightweight-desktop.texi
13186 This example refers to the @file{/boot/efi} file system by its UUID,
13187 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
13188 as returned by the @command{blkid} command.
13190 @xref{Desktop Services}, for the exact list of services provided by
13191 @code{%desktop-services}. @xref{X.509 Certificates}, for background
13192 information about the @code{nss-certs} package that is used here.
13194 Again, @code{%desktop-services} is just a list of service objects. If
13195 you want to remove services from there, you can do so using the
13196 procedures for list filtering (@pxref{SRFI-1 Filtering and
13197 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
13198 following expression returns a list that contains all the services in
13199 @code{%desktop-services} minus the Avahi service:
13202 (remove (lambda (service)
13203 (eq? (service-kind service) avahi-service-type))
13207 @unnumberedsubsec Instantiating the System
13209 Assuming the @code{operating-system} declaration
13210 is stored in the @file{my-system-config.scm}
13211 file, the @command{guix system reconfigure my-system-config.scm} command
13212 instantiates that configuration, and makes it the default GRUB boot
13213 entry (@pxref{Invoking guix system}).
13215 The normal way to change the system configuration is by updating this
13216 file and re-running @command{guix system reconfigure}. One should never
13217 have to touch files in @file{/etc} or to run commands that modify the
13218 system state such as @command{useradd} or @command{grub-install}. In
13219 fact, you must avoid that since that would not only void your warranty
13220 but also prevent you from rolling back to previous versions of your
13221 system, should you ever need to.
13223 @cindex roll-back, of the operating system
13224 Speaking of roll-back, each time you run @command{guix system
13225 reconfigure}, a new @dfn{generation} of the system is created---without
13226 modifying or deleting previous generations. Old system generations get
13227 an entry in the bootloader boot menu, allowing you to boot them in case
13228 something went wrong with the latest generation. Reassuring, no? The
13229 @command{guix system list-generations} command lists the system
13230 generations available on disk. It is also possible to roll back the
13231 system via the commands @command{guix system roll-back} and
13232 @command{guix system switch-generation}.
13234 Although the @command{guix system reconfigure} command will not modify
13235 previous generations, you must take care when the current generation is not
13236 the latest (e.g., after invoking @command{guix system roll-back}), since
13237 the operation might overwrite a later generation (@pxref{Invoking guix
13240 @unnumberedsubsec The Programming Interface
13242 At the Scheme level, the bulk of an @code{operating-system} declaration
13243 is instantiated with the following monadic procedure (@pxref{The Store
13246 @deffn {Monadic Procedure} operating-system-derivation os
13247 Return a derivation that builds @var{os}, an @code{operating-system}
13248 object (@pxref{Derivations}).
13250 The output of the derivation is a single directory that refers to all
13251 the packages, configuration files, and other supporting files needed to
13252 instantiate @var{os}.
13255 This procedure is provided by the @code{(gnu system)} module. Along
13256 with @code{(gnu services)} (@pxref{Services}), this module contains the
13257 guts of Guix System. Make sure to visit it!
13260 @node operating-system Reference
13261 @section @code{operating-system} Reference
13263 This section summarizes all the options available in
13264 @code{operating-system} declarations (@pxref{Using the Configuration
13267 @deftp {Data Type} operating-system
13268 This is the data type representing an operating system configuration.
13269 By that, we mean all the global system configuration, not per-user
13270 configuration (@pxref{Using the Configuration System}).
13273 @item @code{kernel} (default: @code{linux-libre})
13274 The package object of the operating system kernel to
13275 use@footnote{Currently only the Linux-libre kernel is fully supported.
13276 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
13277 available when building a virtual machine disk image.}.
13280 @item @code{hurd} (default: @code{#f})
13281 The package object of the Hurd to be started by the kernel. When this
13282 field is set, produce a GNU/Hurd operating system. In that case,
13283 @code{kernel} must also be set to the @code{gnumach} package---the
13284 microkernel the Hurd runs on.
13287 This feature is experimental and only supported for disk images.
13290 @item @code{kernel-loadable-modules} (default: '())
13291 A list of objects (usually packages) to collect loadable kernel modules
13292 from--e.g. @code{(list ddcci-driver-linux)}.
13294 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
13295 List of strings or gexps representing additional arguments to pass on
13296 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
13298 @item @code{bootloader}
13299 The system bootloader configuration object. @xref{Bootloader Configuration}.
13302 This is the label (a string) as it appears in the bootloader's menu entry.
13303 The default label includes the kernel name and version.
13305 @item @code{keyboard-layout} (default: @code{#f})
13306 This field specifies the keyboard layout to use in the console. It can be
13307 either @code{#f}, in which case the default keyboard layout is used (usually
13308 US English), or a @code{<keyboard-layout>} record.
13310 This keyboard layout is in effect as soon as the kernel has booted. For
13311 instance, it is the keyboard layout in effect when you type a passphrase if
13312 your root file system is on a @code{luks-device-mapping} mapped device
13313 (@pxref{Mapped Devices}).
13316 This does @emph{not} specify the keyboard layout used by the bootloader, nor
13317 that used by the graphical display server. @xref{Bootloader Configuration},
13318 for information on how to specify the bootloader's keyboard layout. @xref{X
13319 Window}, for information on how to specify the keyboard layout used by the X
13323 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
13325 @cindex initial RAM disk
13326 The list of Linux kernel modules that need to be available in the
13327 initial RAM disk. @xref{Initial RAM Disk}.
13329 @item @code{initrd} (default: @code{base-initrd})
13330 A procedure that returns an initial RAM disk for the Linux
13331 kernel. This field is provided to support low-level customization and
13332 should rarely be needed for casual use. @xref{Initial RAM Disk}.
13334 @item @code{firmware} (default: @code{%base-firmware})
13336 List of firmware packages loadable by the operating system kernel.
13338 The default includes firmware needed for Atheros- and Broadcom-based
13339 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
13340 respectively). @xref{Hardware Considerations}, for more info on
13341 supported hardware.
13343 @item @code{host-name}
13346 @item @code{hosts-file}
13348 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
13349 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
13350 Reference Manual}). The default is a file with entries for
13351 @code{localhost} and @var{host-name}.
13353 @item @code{mapped-devices} (default: @code{'()})
13354 A list of mapped devices. @xref{Mapped Devices}.
13356 @item @code{file-systems}
13357 A list of file systems. @xref{File Systems}.
13359 @cindex swap devices
13361 @item @code{swap-devices} (default: @code{'()})
13362 A list of UUIDs, file system labels, or strings identifying devices or
13363 files to be used for ``swap
13364 space'' (@pxref{Memory Concepts,,, libc, The GNU C Library Reference
13365 Manual}). Here are some examples:
13368 @item (list (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb"))
13369 Use the swap partition with the given UUID. You can learn the UUID of a
13370 Linux swap partition by running @command{swaplabel @var{device}}, where
13371 @var{device} is the @file{/dev} file name of that partition.
13373 @item (list (file-system-label "swap"))
13374 Use the partition with label @code{swap}. Again, the
13375 @command{swaplabel} command allows you to view and change the label of a
13376 Linux swap partition.
13378 @item (list "/swapfile")
13379 Use the file @file{/swapfile} as swap space.
13381 @item (list "/dev/sda3" "/dev/sdb2")
13382 Use the @file{/dev/sda3} and @file{/dev/sdb2} partitions as swap space.
13383 We recommend referring to swap devices by UUIDs or labels as shown above
13387 It is possible to specify a swap file in a file system on a mapped
13388 device (under @file{/dev/mapper}), provided that the necessary device
13389 mapping and file system are also specified. @xref{Mapped Devices} and
13390 @ref{File Systems}.
13392 @item @code{users} (default: @code{%base-user-accounts})
13393 @itemx @code{groups} (default: @code{%base-groups})
13394 List of user accounts and groups. @xref{User Accounts}.
13396 If the @code{users} list lacks a user account with UID@tie{}0, a
13397 ``root'' account with UID@tie{}0 is automatically added.
13399 @item @code{skeletons} (default: @code{(default-skeletons)})
13400 A list of target file name/file-like object tuples (@pxref{G-Expressions,
13401 file-like objects}). These are the skeleton files that will be added to
13402 the home directory of newly-created user accounts.
13404 For instance, a valid value may look like this:
13407 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
13408 (".guile" ,(plain-file "guile"
13409 "(use-modules (ice-9 readline))
13410 (activate-readline)")))
13413 @item @code{issue} (default: @code{%default-issue})
13414 A string denoting the contents of the @file{/etc/issue} file, which is
13415 displayed when users log in on a text console.
13417 @item @code{packages} (default: @code{%base-packages})
13418 A list of packages to be installed in the global profile, which is accessible
13419 at @file{/run/current-system/profile}. Each element is either a package
13420 variable or a package/output tuple. Here's a simple example of both:
13423 (cons* git ; the default "out" output
13424 (list git "send-email") ; another output of git
13425 %base-packages) ; the default set
13428 The default set includes core utilities and it is good practice to
13429 install non-core utilities in user profiles (@pxref{Invoking guix
13432 @item @code{timezone}
13433 A timezone identifying string---e.g., @code{"Europe/Paris"}.
13435 You can run the @command{tzselect} command to find out which timezone
13436 string corresponds to your region. Choosing an invalid timezone name
13437 causes @command{guix system} to fail.
13439 @item @code{locale} (default: @code{"en_US.utf8"})
13440 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
13441 Library Reference Manual}). @xref{Locales}, for more information.
13443 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
13444 The list of locale definitions to be compiled and that may be used at
13445 run time. @xref{Locales}.
13447 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
13448 The list of GNU@tie{}libc packages whose locale data and tools are used
13449 to build the locale definitions. @xref{Locales}, for compatibility
13450 considerations that justify this option.
13452 @item @code{name-service-switch} (default: @code{%default-nss})
13453 Configuration of the libc name service switch (NSS)---a
13454 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
13457 @item @code{services} (default: @code{%base-services})
13458 A list of service objects denoting system services. @xref{Services}.
13460 @cindex essential services
13461 @item @code{essential-services} (default: ...)
13462 The list of ``essential services''---i.e., things like instances of
13463 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
13464 Reference}), which are derived from the operating system definition itself.
13465 As a user you should @emph{never} need to touch this field.
13467 @item @code{pam-services} (default: @code{(base-pam-services)})
13469 @cindex pluggable authentication modules
13470 Linux @dfn{pluggable authentication module} (PAM) services.
13471 @c FIXME: Add xref to PAM services section.
13473 @item @code{setuid-programs} (default: @code{%setuid-programs})
13474 List of string-valued G-expressions denoting setuid programs.
13475 @xref{Setuid Programs}.
13477 @item @code{sudoers-file} (default: @code{%sudoers-specification})
13478 @cindex sudoers file
13479 The contents of the @file{/etc/sudoers} file as a file-like object
13480 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
13482 This file specifies which users can use the @command{sudo} command, what
13483 they are allowed to do, and what privileges they may gain. The default
13484 is that only @code{root} and members of the @code{wheel} group may use
13489 @deffn {Scheme Syntax} this-operating-system
13490 When used in the @emph{lexical scope} of an operating system field definition,
13491 this identifier resolves to the operating system being defined.
13493 The example below shows how to refer to the operating system being defined in
13494 the definition of the @code{label} field:
13497 (use-modules (gnu) (guix))
13501 (label (package-full-name
13502 (operating-system-kernel this-operating-system))))
13505 It is an error to refer to @code{this-operating-system} outside an operating
13512 @section File Systems
13514 The list of file systems to be mounted is specified in the
13515 @code{file-systems} field of the operating system declaration
13516 (@pxref{Using the Configuration System}). Each file system is declared
13517 using the @code{file-system} form, like this:
13521 (mount-point "/home")
13522 (device "/dev/sda3")
13526 As usual, some of the fields are mandatory---those shown in the example
13527 above---while others can be omitted. These are described below.
13529 @deftp {Data Type} file-system
13530 Objects of this type represent file systems to be mounted. They
13531 contain the following members:
13535 This is a string specifying the type of the file system---e.g.,
13538 @item @code{mount-point}
13539 This designates the place where the file system is to be mounted.
13541 @item @code{device}
13542 This names the ``source'' of the file system. It can be one of three
13543 things: a file system label, a file system UUID, or the name of a
13544 @file{/dev} node. Labels and UUIDs offer a way to refer to file
13545 systems without having to hard-code their actual device
13546 name@footnote{Note that, while it is tempting to use
13547 @file{/dev/disk/by-uuid} and similar device names to achieve the same
13548 result, this is not recommended: These special device nodes are created
13549 by the udev daemon and may be unavailable at the time the device is
13552 @findex file-system-label
13553 File system labels are created using the @code{file-system-label}
13554 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
13555 plain strings. Here's an example of a file system referred to by its
13556 label, as shown by the @command{e2label} command:
13560 (mount-point "/home")
13562 (device (file-system-label "my-home")))
13566 UUIDs are converted from their string representation (as shown by the
13567 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
13568 @code{uuid} form expects 16-byte UUIDs as defined in
13569 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
13570 form of UUID used by the ext2 family of file systems and others, but it
13571 is different from ``UUIDs'' found in FAT file systems, for instance.},
13576 (mount-point "/home")
13578 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
13581 When the source of a file system is a mapped device (@pxref{Mapped
13582 Devices}), its @code{device} field @emph{must} refer to the mapped
13583 device name---e.g., @file{"/dev/mapper/root-partition"}.
13584 This is required so that
13585 the system knows that mounting the file system depends on having the
13586 corresponding device mapping established.
13588 @item @code{flags} (default: @code{'()})
13589 This is a list of symbols denoting mount flags. Recognized flags
13590 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
13591 access to special files), @code{no-suid} (ignore setuid and setgid
13592 bits), @code{no-atime} (do not update file access times),
13593 @code{strict-atime} (update file access time), @code{lazy-time} (only
13594 update time on the in-memory version of the file inode), and
13595 @code{no-exec} (disallow program execution).
13596 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
13597 Manual}, for more information on these flags.
13599 @item @code{options} (default: @code{#f})
13600 This is either @code{#f}, or a string denoting mount options passed to
13601 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
13602 Library Reference Manual}, for details and run @command{man 8 mount} for
13603 options for various file systems. Note that the
13604 @code{file-system-options->alist} and @code{alist->file-system-options}
13605 procedures from @code{(gnu system file-systems)} can be used to convert
13606 file system options given as an association list to the string
13607 representation, and vice-versa.
13609 @item @code{mount?} (default: @code{#t})
13610 This value indicates whether to automatically mount the file system when
13611 the system is brought up. When set to @code{#f}, the file system gets
13612 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
13613 is not automatically mounted.
13615 @item @code{needed-for-boot?} (default: @code{#f})
13616 This Boolean value indicates whether the file system is needed when
13617 booting. If that is true, then the file system is mounted when the
13618 initial RAM disk (initrd) is loaded. This is always the case, for
13619 instance, for the root file system.
13621 @item @code{check?} (default: @code{#t})
13622 This Boolean indicates whether the file system needs to be checked for
13623 errors before being mounted.
13625 @item @code{create-mount-point?} (default: @code{#f})
13626 When true, the mount point is created if it does not exist yet.
13628 @item @code{mount-may-fail?} (default: @code{#f})
13629 When true, this indicates that mounting this file system can fail but
13630 that should not be considered an error. This is useful in unusual
13631 cases; an example of this is @code{efivarfs}, a file system that can
13632 only be mounted on EFI/UEFI systems.
13634 @item @code{dependencies} (default: @code{'()})
13635 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
13636 representing file systems that must be mounted or mapped devices that
13637 must be opened before (and unmounted or closed after) this one.
13639 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
13640 a dependency of @file{/sys/fs/cgroup/cpu} and
13641 @file{/sys/fs/cgroup/memory}.
13643 Another example is a file system that depends on a mapped device, for
13644 example for an encrypted partition (@pxref{Mapped Devices}).
13648 @deffn {Scheme Procedure} file-system-label @var{str}
13649 This procedure returns an opaque file system label from @var{str}, a
13653 (file-system-label "home")
13654 @result{} #<file-system-label "home">
13657 File system labels are used to refer to file systems by label rather
13658 than by device name. See above for examples.
13661 The @code{(gnu system file-systems)} exports the following useful
13664 @defvr {Scheme Variable} %base-file-systems
13665 These are essential file systems that are required on normal systems,
13666 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
13667 below). Operating system declarations should always contain at least
13671 @defvr {Scheme Variable} %pseudo-terminal-file-system
13672 This is the file system to be mounted as @file{/dev/pts}. It supports
13673 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
13674 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
13675 Manual}). Pseudo-terminals are used by terminal emulators such as
13679 @defvr {Scheme Variable} %shared-memory-file-system
13680 This file system is mounted as @file{/dev/shm} and is used to support
13681 memory sharing across processes (@pxref{Memory-mapped I/O,
13682 @code{shm_open},, libc, The GNU C Library Reference Manual}).
13685 @defvr {Scheme Variable} %immutable-store
13686 This file system performs a read-only ``bind mount'' of
13687 @file{/gnu/store}, making it read-only for all the users including
13688 @code{root}. This prevents against accidental modification by software
13689 running as @code{root} or by system administrators.
13691 The daemon itself is still able to write to the store: it remounts it
13692 read-write in its own ``name space.''
13695 @defvr {Scheme Variable} %binary-format-file-system
13696 The @code{binfmt_misc} file system, which allows handling of arbitrary
13697 executable file types to be delegated to user space. This requires the
13698 @code{binfmt.ko} kernel module to be loaded.
13701 @defvr {Scheme Variable} %fuse-control-file-system
13702 The @code{fusectl} file system, which allows unprivileged users to mount
13703 and unmount user-space FUSE file systems. This requires the
13704 @code{fuse.ko} kernel module to be loaded.
13707 The @code{(gnu system uuid)} module provides tools to deal with file
13708 system ``unique identifiers'' (UUIDs).
13710 @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
13711 Return an opaque UUID (unique identifier) object of the given @var{type}
13712 (a symbol) by parsing @var{str} (a string):
13715 (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
13716 @result{} #<<uuid> type: dce bv: @dots{}>
13718 (uuid "1234-ABCD" 'fat)
13719 @result{} #<<uuid> type: fat bv: @dots{}>
13722 @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
13723 @code{ntfs}, or one of the commonly found synonyms for these.
13725 UUIDs are another way to unambiguously refer to file systems in
13726 operating system configuration. See the examples above.
13730 @node Btrfs file system
13731 @subsection Btrfs file system
13733 The Btrfs has special features, such as subvolumes, that merit being
13734 explained in more details. The following section attempts to cover
13735 basic as well as complex uses of a Btrfs file system with the Guix
13738 In its simplest usage, a Btrfs file system can be described, for
13743 (mount-point "/home")
13745 (device (file-system-label "my-home")))
13748 The example below is more complex, as it makes use of a Btrfs
13749 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
13750 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
13751 dependency on @code{mapped-devices}):
13755 (device (file-system-label "my-btrfs-pool"))
13758 (options "subvol=rootfs")
13759 (dependencies mapped-devices))
13762 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
13763 top level during the early boot, and rely on their configuration to
13764 refer to the correct subvolume path within that top level. The
13765 bootloaders operating in this way typically produce their configuration
13766 on a running system where the Btrfs partitions are already mounted and
13767 where the subvolume information is readily available. As an example,
13768 @command{grub-mkconfig}, the configuration generator command shipped
13769 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
13770 path of a subvolume.
13772 The Guix System produces a bootloader configuration using the operating
13773 system configuration as its sole input; it is therefore necessary to
13774 extract the subvolume name on which @file{/gnu/store} lives (if any)
13775 from that operating system configuration. To better illustrate,
13776 consider a subvolume named 'rootfs' which contains the root file system
13777 data. In such situation, the GRUB bootloader would only see the top
13778 level of the root Btrfs partition, e.g.:
13782 ├── rootfs (subvolume directory)
13783 ├── gnu (normal directory)
13784 ├── store (normal directory)
13788 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
13789 of the kernel, initrd binaries and any other files referred to in the
13790 GRUB configuration that must be found during the early boot.
13792 The next example shows a nested hierarchy of subvolumes and
13797 ├── rootfs (subvolume)
13798 ├── gnu (normal directory)
13799 ├── store (subvolume)
13803 This scenario would work without mounting the 'store' subvolume.
13804 Mounting 'rootfs' is sufficient, since the subvolume name matches its
13805 intended mount point in the file system hierarchy. Alternatively, the
13806 'store' subvolume could be referred to by setting the @code{subvol}
13807 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
13809 Finally, a more contrived example of nested subvolumes:
13813 ├── root-snapshots (subvolume)
13814 ├── root-current (subvolume)
13815 ├── guix-store (subvolume)
13819 Here, the 'guix-store' subvolume doesn't match its intended mount point,
13820 so it is necessary to mount it. The subvolume must be fully specified,
13821 by passing its file name to the @code{subvol} option. To illustrate,
13822 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
13823 a file system declaration such as:
13827 (device (file-system-label "btrfs-pool-1"))
13828 (mount-point "/gnu/store")
13830 (options "subvol=root-snapshots/root-current/guix-store,\
13831 compress-force=zstd,space_cache=v2"))
13834 @node Mapped Devices
13835 @section Mapped Devices
13837 @cindex device mapping
13838 @cindex mapped devices
13839 The Linux kernel has a notion of @dfn{device mapping}: a block device,
13840 such as a hard disk partition, can be @dfn{mapped} into another device,
13841 usually in @code{/dev/mapper/},
13842 with additional processing over the data that flows through
13843 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
13844 concept of a ``mapped device'' and that of a file system: both boil down
13845 to @emph{translating} input/output operations made on a file to
13846 operations on its backing store. Thus, the Hurd implements mapped
13847 devices, like file systems, using the generic @dfn{translator} mechanism
13848 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
13849 typical example is encryption device mapping: all writes to the mapped
13850 device are encrypted, and all reads are deciphered, transparently.
13851 Guix extends this notion by considering any device or set of devices that
13852 are @dfn{transformed} in some way to create a new device; for instance,
13853 RAID devices are obtained by @dfn{assembling} several other devices, such
13854 as hard disks or partitions, into a new one that behaves as one partition.
13856 Mapped devices are declared using the @code{mapped-device} form,
13857 defined as follows; for examples, see below.
13859 @deftp {Data Type} mapped-device
13860 Objects of this type represent device mappings that will be made when
13861 the system boots up.
13865 This is either a string specifying the name of the block device to be mapped,
13866 such as @code{"/dev/sda3"}, or a list of such strings when several devices
13867 need to be assembled for creating a new one. In case of LVM this is a
13868 string specifying name of the volume group to be mapped.
13871 This string specifies the name of the resulting mapped device. For
13872 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
13873 specifying @code{"my-partition"} leads to the creation of
13874 the @code{"/dev/mapper/my-partition"} device.
13875 For RAID devices of type @code{raid-device-mapping}, the full device name
13876 such as @code{"/dev/md0"} needs to be given.
13877 LVM logical volumes of type @code{lvm-device-mapping} need to
13878 be specified as @code{"VGNAME-LVNAME"}.
13881 This list of strings specifies names of the resulting mapped devices in case
13882 there are several. The format is identical to @var{target}.
13885 This must be a @code{mapped-device-kind} object, which specifies how
13886 @var{source} is mapped to @var{target}.
13890 @defvr {Scheme Variable} luks-device-mapping
13891 This defines LUKS block device encryption using the @command{cryptsetup}
13892 command from the package with the same name. It relies on the
13893 @code{dm-crypt} Linux kernel module.
13896 @defvr {Scheme Variable} raid-device-mapping
13897 This defines a RAID device, which is assembled using the @code{mdadm}
13898 command from the package with the same name. It requires a Linux kernel
13899 module for the appropriate RAID level to be loaded, such as @code{raid456}
13900 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
13903 @cindex LVM, logical volume manager
13904 @defvr {Scheme Variable} lvm-device-mapping
13905 This defines one or more logical volumes for the Linux
13906 @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
13907 The volume group is activated by the @command{vgchange} command from the
13908 @code{lvm2} package.
13911 @cindex disk encryption
13913 The following example specifies a mapping from @file{/dev/sda3} to
13914 @file{/dev/mapper/home} using LUKS---the
13915 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
13916 standard mechanism for disk encryption.
13917 The @file{/dev/mapper/home}
13918 device can then be used as the @code{device} of a @code{file-system}
13919 declaration (@pxref{File Systems}).
13923 (source "/dev/sda3")
13925 (type luks-device-mapping))
13928 Alternatively, to become independent of device numbering, one may obtain
13929 the LUKS UUID (@dfn{unique identifier}) of the source device by a
13933 cryptsetup luksUUID /dev/sda3
13936 and use it as follows:
13940 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
13942 (type luks-device-mapping))
13945 @cindex swap encryption
13946 It is also desirable to encrypt swap space, since swap space may contain
13947 sensitive data. One way to accomplish that is to use a swap file in a
13948 file system on a device mapped via LUKS encryption. In this way, the
13949 swap file is encrypted because the entire device is encrypted.
13950 @xref{Preparing for Installation,,Disk Partitioning}, for an example.
13952 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
13953 may be declared as follows:
13957 (source (list "/dev/sda1" "/dev/sdb1"))
13958 (target "/dev/md0")
13959 (type raid-device-mapping))
13962 The @file{/dev/md0} device can then be used as the @code{device} of a
13963 @code{file-system} declaration (@pxref{File Systems}).
13964 Note that the RAID level need not be given; it is chosen during the
13965 initial creation and formatting of the RAID device and is determined
13966 automatically later.
13968 LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
13969 be declared as follows:
13974 (target (list "vg0-alpha" "vg0-beta"))
13975 (type lvm-device-mapping))
13978 Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
13979 then be used as the @code{device} of a @code{file-system} declaration
13980 (@pxref{File Systems}).
13982 @node User Accounts
13983 @section User Accounts
13987 @cindex user accounts
13988 User accounts and groups are entirely managed through the
13989 @code{operating-system} declaration. They are specified with the
13990 @code{user-account} and @code{user-group} forms:
13996 (supplementary-groups '("wheel" ;allow use of sudo, etc.
13997 "audio" ;sound card
13998 "video" ;video devices such as webcams
13999 "cdrom")) ;the good ol' CD-ROM
14000 (comment "Bob's sister"))
14003 Here's a user account that uses a different shell and a custom home
14004 directory (the default would be @file{"/home/bob"}):
14010 (comment "Alice's bro")
14011 (shell (file-append zsh "/bin/zsh"))
14012 (home-directory "/home/robert"))
14015 When booting or upon completion of @command{guix system reconfigure},
14016 the system ensures that only the user accounts and groups specified in
14017 the @code{operating-system} declaration exist, and with the specified
14018 properties. Thus, account or group creations or modifications made by
14019 directly invoking commands such as @command{useradd} are lost upon
14020 reconfiguration or reboot. This ensures that the system remains exactly
14023 @deftp {Data Type} user-account
14024 Objects of this type represent user accounts. The following members may
14029 The name of the user account.
14033 This is the name (a string) or identifier (a number) of the user group
14034 this account belongs to.
14036 @item @code{supplementary-groups} (default: @code{'()})
14037 Optionally, this can be defined as a list of group names that this
14038 account belongs to.
14040 @item @code{uid} (default: @code{#f})
14041 This is the user ID for this account (a number), or @code{#f}. In the
14042 latter case, a number is automatically chosen by the system when the
14043 account is created.
14045 @item @code{comment} (default: @code{""})
14046 A comment about the account, such as the account owner's full name.
14048 @item @code{home-directory}
14049 This is the name of the home directory for the account.
14051 @item @code{create-home-directory?} (default: @code{#t})
14052 Indicates whether the home directory of this account should be created
14053 if it does not exist yet.
14055 @item @code{shell} (default: Bash)
14056 This is a G-expression denoting the file name of a program to be used as
14057 the shell (@pxref{G-Expressions}). For example, you would refer to the
14058 Bash executable like this:
14061 (file-append bash "/bin/bash")
14065 ... and to the Zsh executable like that:
14068 (file-append zsh "/bin/zsh")
14071 @item @code{system?} (default: @code{#f})
14072 This Boolean value indicates whether the account is a ``system''
14073 account. System accounts are sometimes treated specially; for instance,
14074 graphical login managers do not list them.
14076 @anchor{user-account-password}
14077 @cindex password, for user accounts
14078 @item @code{password} (default: @code{#f})
14079 You would normally leave this field to @code{#f}, initialize user
14080 passwords as @code{root} with the @command{passwd} command, and then let
14081 users change it with @command{passwd}. Passwords set with
14082 @command{passwd} are of course preserved across reboot and
14085 If you @emph{do} want to set an initial password for an account, then
14086 this field must contain the encrypted password, as a string. You can use the
14087 @code{crypt} procedure for this purpose:
14094 ;; Specify a SHA-512-hashed initial password.
14095 (password (crypt "InitialPassword!" "$6$abc")))
14099 The hash of this initial password will be available in a file in
14100 @file{/gnu/store}, readable by all the users, so this method must be used with
14104 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
14105 more information on password encryption, and @ref{Encryption,,, guile, GNU
14106 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
14112 User group declarations are even simpler:
14115 (user-group (name "students"))
14118 @deftp {Data Type} user-group
14119 This type is for, well, user groups. There are just a few fields:
14123 The name of the group.
14125 @item @code{id} (default: @code{#f})
14126 The group identifier (a number). If @code{#f}, a new number is
14127 automatically allocated when the group is created.
14129 @item @code{system?} (default: @code{#f})
14130 This Boolean value indicates whether the group is a ``system'' group.
14131 System groups have low numerical IDs.
14133 @item @code{password} (default: @code{#f})
14134 What, user groups can have a password? Well, apparently yes. Unless
14135 @code{#f}, this field specifies the password of the group.
14140 For convenience, a variable lists all the basic user groups one may
14143 @defvr {Scheme Variable} %base-groups
14144 This is the list of basic user groups that users and/or packages expect
14145 to be present on the system. This includes groups such as ``root'',
14146 ``wheel'', and ``users'', as well as groups used to control access to
14147 specific devices such as ``audio'', ``disk'', and ``cdrom''.
14150 @defvr {Scheme Variable} %base-user-accounts
14151 This is the list of basic system accounts that programs may expect to
14152 find on a GNU/Linux system, such as the ``nobody'' account.
14154 Note that the ``root'' account is not included here. It is a
14155 special-case and is automatically added whether or not it is specified.
14158 @node Keyboard Layout
14159 @section Keyboard Layout
14161 @cindex keyboard layout
14163 To specify what each key of your keyboard does, you need to tell the operating
14164 system what @dfn{keyboard layout} you want to use. The default, when nothing
14165 is specified, is the US English QWERTY layout for 105-key PC keyboards.
14166 However, German speakers will usually prefer the German QWERTZ layout, French
14167 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
14168 or bépo, and they might even want to further customize the effect of some of
14169 the keys. This section explains how to get that done.
14171 @cindex keyboard layout, definition
14172 There are three components that will want to know about your keyboard layout:
14176 The @emph{bootloader} may want to know what keyboard layout you want to use
14177 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
14178 you want, for instance, to make sure that you can type the passphrase of your
14179 encrypted root partition using the right layout.
14182 The @emph{operating system kernel}, Linux, will need that so that the console
14183 is properly configured (@pxref{operating-system Reference,
14184 @code{keyboard-layout}}).
14187 The @emph{graphical display server}, usually Xorg, also has its own idea of
14188 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
14191 Guix allows you to configure all three separately but, fortunately, it allows
14192 you to share the same keyboard layout for all three components.
14194 @cindex XKB, keyboard layouts
14195 Keyboard layouts are represented by records created by the
14196 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
14197 the X Keyboard extension (XKB), each layout has four attributes: a name (often
14198 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
14199 optional variant name, an optional keyboard model name, and a possibly empty
14200 list of additional options. In most cases the layout name is all you care
14203 @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
14204 [#:model] [#:options '()]
14205 Return a new keyboard layout with the given @var{name} and @var{variant}.
14207 @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
14208 string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
14209 @code{xkeyboard-config} package for valid options.
14212 Here are a few examples:
14215 ;; The German QWERTZ layout. Here we assume a standard
14216 ;; "pc105" keyboard model.
14217 (keyboard-layout "de")
14219 ;; The bépo variant of the French layout.
14220 (keyboard-layout "fr" "bepo")
14222 ;; The Catalan layout.
14223 (keyboard-layout "es" "cat")
14225 ;; Arabic layout with "Alt-Shift" to switch to US layout.
14226 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
14228 ;; The Latin American Spanish layout. In addition, the
14229 ;; "Caps Lock" key is used as an additional "Ctrl" key,
14230 ;; and the "Menu" key is used as a "Compose" key to enter
14231 ;; accented letters.
14232 (keyboard-layout "latam"
14233 #:options '("ctrl:nocaps" "compose:menu"))
14235 ;; The Russian layout for a ThinkPad keyboard.
14236 (keyboard-layout "ru" #:model "thinkpad")
14238 ;; The "US international" layout, which is the US layout plus
14239 ;; dead keys to enter accented characters. This is for an
14240 ;; Apple MacBook keyboard.
14241 (keyboard-layout "us" "intl" #:model "macbook78")
14244 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
14245 for a complete list of supported layouts, variants, and models.
14247 @cindex keyboard layout, configuration
14248 Let's say you want your system to use the Turkish keyboard layout throughout
14249 your system---bootloader, console, and Xorg. Here's what your system
14250 configuration would look like:
14252 @findex set-xorg-configuration
14254 ;; Using the Turkish layout for the bootloader, the console,
14259 (keyboard-layout (keyboard-layout "tr")) ;for the console
14260 (bootloader (bootloader-configuration
14261 (bootloader grub-efi-bootloader)
14262 (target "/boot/efi")
14263 (keyboard-layout keyboard-layout))) ;for GRUB
14264 (services (cons (set-xorg-configuration
14265 (xorg-configuration ;for Xorg
14266 (keyboard-layout keyboard-layout)))
14267 %desktop-services)))
14270 In the example above, for GRUB and for Xorg, we just refer to the
14271 @code{keyboard-layout} field defined above, but we could just as well refer to
14272 a different layout. The @code{set-xorg-configuration} procedure communicates
14273 the desired Xorg configuration to the graphical log-in manager, by default
14276 We've discussed how to specify the @emph{default} keyboard layout of your
14277 system when it starts, but you can also adjust it at run time:
14281 If you're using GNOME, its settings panel has a ``Region & Language'' entry
14282 where you can select one or more keyboard layouts.
14285 Under Xorg, the @command{setxkbmap} command (from the same-named package)
14286 allows you to change the current layout. For example, this is how you would
14287 change the layout to US Dvorak:
14290 setxkbmap us dvorak
14294 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
14295 console. However, note that @code{loadkeys} does @emph{not} use the XKB
14296 keyboard layout categorization described above. The command below loads the
14297 French bépo layout:
14308 A @dfn{locale} defines cultural conventions for a particular language
14309 and region of the world (@pxref{Locales,,, libc, The GNU C Library
14310 Reference Manual}). Each locale has a name that typically has the form
14311 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
14312 @code{fr_LU.utf8} designates the locale for the French language, with
14313 cultural conventions from Luxembourg, and using the UTF-8 encoding.
14315 @cindex locale definition
14316 Usually, you will want to specify the default locale for the machine
14317 using the @code{locale} field of the @code{operating-system} declaration
14318 (@pxref{operating-system Reference, @code{locale}}).
14320 The selected locale is automatically added to the @dfn{locale
14321 definitions} known to the system if needed, with its codeset inferred
14322 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
14323 @code{UTF-8} codeset. Additional locale definitions can be specified in
14324 the @code{locale-definitions} slot of @code{operating-system}---this is
14325 useful, for instance, if the codeset could not be inferred from the
14326 locale name. The default set of locale definitions includes some widely
14327 used locales, but not all the available locales, in order to save space.
14329 For instance, to add the North Frisian locale for Germany, the value of
14333 (cons (locale-definition
14334 (name "fy_DE.utf8") (source "fy_DE"))
14335 %default-locale-definitions)
14338 Likewise, to save space, one might want @code{locale-definitions} to
14339 list only the locales that are actually used, as in:
14342 (list (locale-definition
14343 (name "ja_JP.eucjp") (source "ja_JP")
14344 (charset "EUC-JP")))
14348 The compiled locale definitions are available at
14349 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
14350 version, which is the default location where the GNU@tie{}libc provided
14351 by Guix looks for locale data. This can be overridden using the
14352 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
14353 @env{LOCPATH} and locale packages}).
14355 The @code{locale-definition} form is provided by the @code{(gnu system
14356 locale)} module. Details are given below.
14358 @deftp {Data Type} locale-definition
14359 This is the data type of a locale definition.
14364 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
14365 Reference Manual}, for more information on locale names.
14367 @item @code{source}
14368 The name of the source for that locale. This is typically the
14369 @code{@var{language}_@var{territory}} part of the locale name.
14371 @item @code{charset} (default: @code{"UTF-8"})
14372 The ``character set'' or ``code set'' for that locale,
14373 @uref{https://www.iana.org/assignments/character-sets, as defined by
14379 @defvr {Scheme Variable} %default-locale-definitions
14380 A list of commonly used UTF-8 locales, used as the default
14381 value of the @code{locale-definitions} field of @code{operating-system}
14384 @cindex locale name
14385 @cindex normalized codeset in locale names
14386 These locale definitions use the @dfn{normalized codeset} for the part
14387 that follows the dot in the name (@pxref{Using gettextized software,
14388 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
14389 instance it has @code{uk_UA.utf8} but @emph{not}, say,
14390 @code{uk_UA.UTF-8}.
14393 @subsection Locale Data Compatibility Considerations
14395 @cindex incompatibility, of locale data
14396 @code{operating-system} declarations provide a @code{locale-libcs} field
14397 to specify the GNU@tie{}libc packages that are used to compile locale
14398 declarations (@pxref{operating-system Reference}). ``Why would I
14399 care?'', you may ask. Well, it turns out that the binary format of
14400 locale data is occasionally incompatible from one libc version to
14403 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
14404 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
14405 For instance, a program linked against libc version 2.21 is unable to
14406 read locale data produced with libc 2.22; worse, that program
14407 @emph{aborts} instead of simply ignoring the incompatible locale
14408 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
14409 the incompatible locale data, which is already an improvement.}.
14410 Similarly, a program linked against libc 2.22 can read most, but not
14411 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
14412 data is incompatible); thus calls to @code{setlocale} may fail, but
14413 programs will not abort.
14415 The ``problem'' with Guix is that users have a lot of freedom: They can
14416 choose whether and when to upgrade software in their profiles, and might
14417 be using a libc version different from the one the system administrator
14418 used to build the system-wide locale data.
14420 Fortunately, unprivileged users can also install their own locale data
14421 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
14422 @env{GUIX_LOCPATH} and locale packages}).
14424 Still, it is best if the system-wide locale data at
14425 @file{/run/current-system/locale} is built for all the libc versions
14426 actually in use on the system, so that all the programs can access
14427 it---this is especially crucial on a multi-user system. To do that, the
14428 administrator can specify several libc packages in the
14429 @code{locale-libcs} field of @code{operating-system}:
14432 (use-package-modules base)
14436 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
14439 This example would lead to a system containing locale definitions for
14440 both libc 2.21 and the current version of libc in
14441 @file{/run/current-system/locale}.
14447 @cindex system services
14448 An important part of preparing an @code{operating-system} declaration is
14449 listing @dfn{system services} and their configuration (@pxref{Using the
14450 Configuration System}). System services are typically daemons launched
14451 when the system boots, or other actions needed at that time---e.g.,
14452 configuring network access.
14454 Guix has a broad definition of ``service'' (@pxref{Service
14455 Composition}), but many services are managed by the GNU@tie{}Shepherd
14456 (@pxref{Shepherd Services}). On a running system, the @command{herd}
14457 command allows you to list the available services, show their status,
14458 start and stop them, or do other specific operations (@pxref{Jump
14459 Start,,, shepherd, The GNU Shepherd Manual}). For example:
14465 The above command, run as @code{root}, lists the currently defined
14466 services. The @command{herd doc} command shows a synopsis of the given
14467 service and its associated actions:
14471 Run libc's name service cache daemon (nscd).
14473 # herd doc nscd action invalidate
14474 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
14477 The @command{start}, @command{stop}, and @command{restart} sub-commands
14478 have the effect you would expect. For instance, the commands below stop
14479 the nscd service and restart the Xorg display server:
14483 Service nscd has been stopped.
14484 # herd restart xorg-server
14485 Service xorg-server has been stopped.
14486 Service xorg-server has been started.
14489 The following sections document the available services, starting with
14490 the core services, that may be used in an @code{operating-system}
14494 * Base Services:: Essential system services.
14495 * Scheduled Job Execution:: The mcron service.
14496 * Log Rotation:: The rottlog service.
14497 * Networking Services:: Network setup, SSH daemon, etc.
14498 * Unattended Upgrades:: Automated system upgrades.
14499 * X Window:: Graphical display.
14500 * Printing Services:: Local and remote printer support.
14501 * Desktop Services:: D-Bus and desktop services.
14502 * Sound Services:: ALSA and Pulseaudio services.
14503 * Database Services:: SQL databases, key-value stores, etc.
14504 * Mail Services:: IMAP, POP3, SMTP, and all that.
14505 * Messaging Services:: Messaging services.
14506 * Telephony Services:: Telephony services.
14507 * Monitoring Services:: Monitoring services.
14508 * Kerberos Services:: Kerberos services.
14509 * LDAP Services:: LDAP services.
14510 * Web Services:: Web servers.
14511 * Certificate Services:: TLS certificates via Let's Encrypt.
14512 * DNS Services:: DNS daemons.
14513 * VPN Services:: VPN daemons.
14514 * Network File System:: NFS related services.
14515 * Continuous Integration:: The Cuirass service.
14516 * Power Management Services:: Extending battery life.
14517 * Audio Services:: The MPD.
14518 * Virtualization Services:: Virtualization services.
14519 * Version Control Services:: Providing remote access to Git repositories.
14520 * Game Services:: Game servers.
14521 * PAM Mount Service:: Service to mount volumes when logging in.
14522 * Guix Services:: Services relating specifically to Guix.
14523 * Linux Services:: Services tied to the Linux kernel.
14524 * Hurd Services:: Services specific for a Hurd System.
14525 * Miscellaneous Services:: Other services.
14528 @node Base Services
14529 @subsection Base Services
14531 The @code{(gnu services base)} module provides definitions for the basic
14532 services that one expects from the system. The services exported by
14533 this module are listed below.
14535 @defvr {Scheme Variable} %base-services
14536 This variable contains a list of basic services (@pxref{Service Types
14537 and Services}, for more information on service objects) one would
14538 expect from the system: a login service (mingetty) on each tty, syslogd,
14539 the libc name service cache daemon (nscd), the udev device manager, and
14542 This is the default value of the @code{services} field of
14543 @code{operating-system} declarations. Usually, when customizing a
14544 system, you will want to append services to @code{%base-services}, like
14548 (append (list (service avahi-service-type)
14549 (service openssh-service-type))
14554 @defvr {Scheme Variable} special-files-service-type
14555 This is the service that sets up ``special files'' such as
14556 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
14558 The value associated with @code{special-files-service-type} services
14559 must be a list of tuples where the first element is the ``special file''
14560 and the second element is its target. By default it is:
14562 @cindex @file{/bin/sh}
14563 @cindex @file{sh}, in @file{/bin}
14565 `(("/bin/sh" ,(file-append bash "/bin/sh")))
14568 @cindex @file{/usr/bin/env}
14569 @cindex @file{env}, in @file{/usr/bin}
14570 If you want to add, say, @code{/usr/bin/env} to your system, you can
14574 `(("/bin/sh" ,(file-append bash "/bin/sh"))
14575 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
14578 Since this is part of @code{%base-services}, you can use
14579 @code{modify-services} to customize the set of special files
14580 (@pxref{Service Reference, @code{modify-services}}). But the simple way
14581 to add a special file is @i{via} the @code{extra-special-file} procedure
14585 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
14586 Use @var{target} as the ``special file'' @var{file}.
14588 For example, adding the following lines to the @code{services} field of
14589 your operating system declaration leads to a @file{/usr/bin/env}
14593 (extra-special-file "/usr/bin/env"
14594 (file-append coreutils "/bin/env"))
14598 @deffn {Scheme Procedure} host-name-service @var{name}
14599 Return a service that sets the host name to @var{name}.
14602 @defvr {Scheme Variable} console-font-service-type
14603 Install the given fonts on the specified ttys (fonts are per
14604 virtual console on the kernel Linux). The value of this service is a list of
14605 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
14606 package or any valid argument to @command{setfont}, as in this example:
14609 `(("tty1" . "LatGrkCyr-8x16")
14610 ("tty2" . ,(file-append
14612 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
14613 ("tty3" . ,(file-append
14615 "/share/consolefonts/ter-132n"))) ; for HDPI
14619 @deffn {Scheme Procedure} login-service @var{config}
14620 Return a service to run login according to @var{config}, a
14621 @code{<login-configuration>} object, which specifies the message of the day,
14622 among other things.
14625 @deftp {Data Type} login-configuration
14626 This is the data type representing the configuration of login.
14631 @cindex message of the day
14632 A file-like object containing the ``message of the day''.
14634 @item @code{allow-empty-passwords?} (default: @code{#t})
14635 Allow empty passwords by default so that first-time users can log in when
14636 the 'root' account has just been created.
14641 @deffn {Scheme Procedure} mingetty-service @var{config}
14642 Return a service to run mingetty according to @var{config}, a
14643 @code{<mingetty-configuration>} object, which specifies the tty to run, among
14647 @deftp {Data Type} mingetty-configuration
14648 This is the data type representing the configuration of Mingetty, which
14649 provides the default implementation of virtual console log-in.
14654 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
14656 @item @code{auto-login} (default: @code{#f})
14657 When true, this field must be a string denoting the user name under
14658 which the system automatically logs in. When it is @code{#f}, a
14659 user name and password must be entered to log in.
14661 @item @code{login-program} (default: @code{#f})
14662 This must be either @code{#f}, in which case the default log-in program
14663 is used (@command{login} from the Shadow tool suite), or a gexp denoting
14664 the name of the log-in program.
14666 @item @code{login-pause?} (default: @code{#f})
14667 When set to @code{#t} in conjunction with @var{auto-login}, the user
14668 will have to press a key before the log-in shell is launched.
14670 @item @code{clear-on-logout?} (default: @code{#t})
14671 When set to @code{#t}, the screen will be cleared after logout.
14673 @item @code{mingetty} (default: @var{mingetty})
14674 The Mingetty package to use.
14679 @deffn {Scheme Procedure} agetty-service @var{config}
14680 Return a service to run agetty according to @var{config}, an
14681 @code{<agetty-configuration>} object, which specifies the tty to run,
14682 among other things.
14685 @deftp {Data Type} agetty-configuration
14686 This is the data type representing the configuration of agetty, which
14687 implements virtual and serial console log-in. See the @code{agetty(8)}
14688 man page for more information.
14693 The name of the console this agetty runs on, as a string---e.g.,
14694 @code{"ttyS0"}. This argument is optional, it will default to
14695 a reasonable default serial port used by the kernel Linux.
14697 For this, if there is a value for an option @code{agetty.tty} in the kernel
14698 command line, agetty will extract the device name of the serial port
14699 from it and use that.
14701 If not and if there is a value for an option @code{console} with a tty in
14702 the Linux command line, agetty will extract the device name of the
14703 serial port from it and use that.
14705 In both cases, agetty will leave the other serial device settings
14706 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
14709 @item @code{baud-rate} (default: @code{#f})
14710 A string containing a comma-separated list of one or more baud rates, in
14713 @item @code{term} (default: @code{#f})
14714 A string containing the value used for the @env{TERM} environment
14717 @item @code{eight-bits?} (default: @code{#f})
14718 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
14721 @item @code{auto-login} (default: @code{#f})
14722 When passed a login name, as a string, the specified user will be logged
14723 in automatically without prompting for their login name or password.
14725 @item @code{no-reset?} (default: @code{#f})
14726 When @code{#t}, don't reset terminal cflags (control modes).
14728 @item @code{host} (default: @code{#f})
14729 This accepts a string containing the ``login_host'', which will be written
14730 into the @file{/var/run/utmpx} file.
14732 @item @code{remote?} (default: @code{#f})
14733 When set to @code{#t} in conjunction with @var{host}, this will add an
14734 @code{-r} fakehost option to the command line of the login program
14735 specified in @var{login-program}.
14737 @item @code{flow-control?} (default: @code{#f})
14738 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
14740 @item @code{no-issue?} (default: @code{#f})
14741 When set to @code{#t}, the contents of the @file{/etc/issue} file will
14742 not be displayed before presenting the login prompt.
14744 @item @code{init-string} (default: @code{#f})
14745 This accepts a string that will be sent to the tty or modem before
14746 sending anything else. It can be used to initialize a modem.
14748 @item @code{no-clear?} (default: @code{#f})
14749 When set to @code{#t}, agetty will not clear the screen before showing
14752 @item @code{login-program} (default: (file-append shadow "/bin/login"))
14753 This must be either a gexp denoting the name of a log-in program, or
14754 unset, in which case the default value is the @command{login} from the
14757 @item @code{local-line} (default: @code{#f})
14758 Control the CLOCAL line flag. This accepts one of three symbols as
14759 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
14760 the default value chosen by agetty is @code{'auto}.
14762 @item @code{extract-baud?} (default: @code{#f})
14763 When set to @code{#t}, instruct agetty to try to extract the baud rate
14764 from the status messages produced by certain types of modems.
14766 @item @code{skip-login?} (default: @code{#f})
14767 When set to @code{#t}, do not prompt the user for a login name. This
14768 can be used with @var{login-program} field to use non-standard login
14771 @item @code{no-newline?} (default: @code{#f})
14772 When set to @code{#t}, do not print a newline before printing the
14773 @file{/etc/issue} file.
14775 @c Is this dangerous only when used with login-program, or always?
14776 @item @code{login-options} (default: @code{#f})
14777 This option accepts a string containing options that are passed to the
14778 login program. When used with the @var{login-program}, be aware that a
14779 malicious user could try to enter a login name containing embedded
14780 options that could be parsed by the login program.
14782 @item @code{login-pause} (default: @code{#f})
14783 When set to @code{#t}, wait for any key before showing the login prompt.
14784 This can be used in conjunction with @var{auto-login} to save memory by
14785 lazily spawning shells.
14787 @item @code{chroot} (default: @code{#f})
14788 Change root to the specified directory. This option accepts a directory
14791 @item @code{hangup?} (default: @code{#f})
14792 Use the Linux system call @code{vhangup} to do a virtual hangup of the
14793 specified terminal.
14795 @item @code{keep-baud?} (default: @code{#f})
14796 When set to @code{#t}, try to keep the existing baud rate. The baud
14797 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
14800 @item @code{timeout} (default: @code{#f})
14801 When set to an integer value, terminate if no user name could be read
14802 within @var{timeout} seconds.
14804 @item @code{detect-case?} (default: @code{#f})
14805 When set to @code{#t}, turn on support for detecting an uppercase-only
14806 terminal. This setting will detect a login name containing only
14807 uppercase letters as indicating an uppercase-only terminal and turn on
14808 some upper-to-lower case conversions. Note that this will not support
14809 Unicode characters.
14811 @item @code{wait-cr?} (default: @code{#f})
14812 When set to @code{#t}, wait for the user or modem to send a
14813 carriage-return or linefeed character before displaying
14814 @file{/etc/issue} or login prompt. This is typically used with the
14815 @var{init-string} option.
14817 @item @code{no-hints?} (default: @code{#f})
14818 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
14821 @item @code{no-hostname?} (default: @code{#f})
14822 By default, the hostname is printed. When this option is set to
14823 @code{#t}, no hostname will be shown at all.
14825 @item @code{long-hostname?} (default: @code{#f})
14826 By default, the hostname is only printed until the first dot. When this
14827 option is set to @code{#t}, the fully qualified hostname by
14828 @code{gethostname} or @code{getaddrinfo} is shown.
14830 @item @code{erase-characters} (default: @code{#f})
14831 This option accepts a string of additional characters that should be
14832 interpreted as backspace when the user types their login name.
14834 @item @code{kill-characters} (default: @code{#f})
14835 This option accepts a string that should be interpreted to mean ``ignore
14836 all previous characters'' (also called a ``kill'' character) when the user
14837 types their login name.
14839 @item @code{chdir} (default: @code{#f})
14840 This option accepts, as a string, a directory path that will be changed
14843 @item @code{delay} (default: @code{#f})
14844 This options accepts, as an integer, the number of seconds to sleep
14845 before opening the tty and displaying the login prompt.
14847 @item @code{nice} (default: @code{#f})
14848 This option accepts, as an integer, the nice value with which to run the
14849 @command{login} program.
14851 @item @code{extra-options} (default: @code{'()})
14852 This option provides an ``escape hatch'' for the user to provide arbitrary
14853 command-line arguments to @command{agetty} as a list of strings.
14858 @deffn {Scheme Procedure} kmscon-service-type @var{config}
14859 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
14860 according to @var{config}, a @code{<kmscon-configuration>} object, which
14861 specifies the tty to run, among other things.
14864 @deftp {Data Type} kmscon-configuration
14865 This is the data type representing the configuration of Kmscon, which
14866 implements virtual console log-in.
14870 @item @code{virtual-terminal}
14871 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
14873 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
14874 A gexp denoting the name of the log-in program. The default log-in program is
14875 @command{login} from the Shadow tool suite.
14877 @item @code{login-arguments} (default: @code{'("-p")})
14878 A list of arguments to pass to @command{login}.
14880 @item @code{auto-login} (default: @code{#f})
14881 When passed a login name, as a string, the specified user will be logged
14882 in automatically without prompting for their login name or password.
14884 @item @code{hardware-acceleration?} (default: #f)
14885 Whether to use hardware acceleration.
14887 @item @code{kmscon} (default: @var{kmscon})
14888 The Kmscon package to use.
14893 @cindex name service cache daemon
14895 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
14896 [#:name-services '()]
14897 Return a service that runs the libc name service cache daemon (nscd) with the
14898 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
14899 Service Switch}, for an example.
14901 For convenience, the Shepherd service for nscd provides the following actions:
14905 @cindex cache invalidation, nscd
14906 @cindex nscd, cache invalidation
14907 This invalidate the given cache. For instance, running:
14910 herd invalidate nscd hosts
14914 invalidates the host name lookup cache of nscd.
14917 Running @command{herd statistics nscd} displays information about nscd usage
14923 @defvr {Scheme Variable} %nscd-default-configuration
14924 This is the default @code{<nscd-configuration>} value (see below) used
14925 by @code{nscd-service}. It uses the caches defined by
14926 @code{%nscd-default-caches}; see below.
14929 @deftp {Data Type} nscd-configuration
14930 This is the data type representing the name service cache daemon (nscd)
14935 @item @code{name-services} (default: @code{'()})
14936 List of packages denoting @dfn{name services} that must be visible to
14937 the nscd---e.g., @code{(list @var{nss-mdns})}.
14939 @item @code{glibc} (default: @var{glibc})
14940 Package object denoting the GNU C Library providing the @command{nscd}
14943 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
14944 Name of the nscd log file. This is where debugging output goes when
14945 @code{debug-level} is strictly positive.
14947 @item @code{debug-level} (default: @code{0})
14948 Integer denoting the debugging levels. Higher numbers mean that more
14949 debugging output is logged.
14951 @item @code{caches} (default: @code{%nscd-default-caches})
14952 List of @code{<nscd-cache>} objects denoting things to be cached; see
14958 @deftp {Data Type} nscd-cache
14959 Data type representing a cache database of nscd and its parameters.
14963 @item @code{database}
14964 This is a symbol representing the name of the database to be cached.
14965 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
14966 @code{services}, which designate the corresponding NSS database
14967 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
14969 @item @code{positive-time-to-live}
14970 @itemx @code{negative-time-to-live} (default: @code{20})
14971 A number representing the number of seconds during which a positive or
14972 negative lookup result remains in cache.
14974 @item @code{check-files?} (default: @code{#t})
14975 Whether to check for updates of the files corresponding to
14978 For instance, when @var{database} is @code{hosts}, setting this flag
14979 instructs nscd to check for updates in @file{/etc/hosts} and to take
14982 @item @code{persistent?} (default: @code{#t})
14983 Whether the cache should be stored persistently on disk.
14985 @item @code{shared?} (default: @code{#t})
14986 Whether the cache should be shared among users.
14988 @item @code{max-database-size} (default: 32@tie{}MiB)
14989 Maximum size in bytes of the database cache.
14991 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
14992 @c settings, so leave them out.
14997 @defvr {Scheme Variable} %nscd-default-caches
14998 List of @code{<nscd-cache>} objects used by default by
14999 @code{nscd-configuration} (see above).
15001 It enables persistent and aggressive caching of service and host name
15002 lookups. The latter provides better host name lookup performance,
15003 resilience in the face of unreliable name servers, and also better
15004 privacy---often the result of host name lookups is in local cache, so
15005 external name servers do not even need to be queried.
15008 @anchor{syslog-configuration-type}
15011 @deftp {Data Type} syslog-configuration
15012 This data type represents the configuration of the syslog daemon.
15015 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
15016 The syslog daemon to use.
15018 @item @code{config-file} (default: @code{%default-syslog.conf})
15019 The syslog configuration file to use.
15024 @anchor{syslog-service}
15026 @deffn {Scheme Procedure} syslog-service @var{config}
15027 Return a service that runs a syslog daemon according to @var{config}.
15029 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
15030 information on the configuration file syntax.
15033 @defvr {Scheme Variable} guix-service-type
15034 This is the type of the service that runs the build daemon,
15035 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
15036 @code{guix-configuration} record as described below.
15039 @anchor{guix-configuration-type}
15040 @deftp {Data Type} guix-configuration
15041 This data type represents the configuration of the Guix build daemon.
15042 @xref{Invoking guix-daemon}, for more information.
15045 @item @code{guix} (default: @var{guix})
15046 The Guix package to use.
15048 @item @code{build-group} (default: @code{"guixbuild"})
15049 Name of the group for build user accounts.
15051 @item @code{build-accounts} (default: @code{10})
15052 Number of build user accounts to create.
15054 @item @code{authorize-key?} (default: @code{#t})
15055 @cindex substitutes, authorization thereof
15056 Whether to authorize the substitute keys listed in
15057 @code{authorized-keys}---by default that of @code{@value{SUBSTITUTE-SERVER}}
15058 (@pxref{Substitutes}).
15060 When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
15061 changed by invoking @command{guix archive --authorize}. You must
15062 instead adjust @code{guix-configuration} as you wish and reconfigure the
15063 system. This ensures that your operating system configuration file is
15067 When booting or reconfiguring to a system where @code{authorize-key?}
15068 is true, the existing @file{/etc/guix/acl} file is backed up as
15069 @file{/etc/guix/acl.bak} if it was determined to be a manually modified
15070 file. This is to facilitate migration from earlier versions, which
15071 allowed for in-place modifications to @file{/etc/guix/acl}.
15074 @vindex %default-authorized-guix-keys
15075 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
15076 The list of authorized key files for archive imports, as a list of
15077 string-valued gexps (@pxref{Invoking guix archive}). By default, it
15078 contains that of @code{@value{SUBSTITUTE-SERVER}} (@pxref{Substitutes}).
15079 See @code{substitute-urls} below for an example on how to change it.
15081 @item @code{use-substitutes?} (default: @code{#t})
15082 Whether to use substitutes.
15084 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
15085 The list of URLs where to look for substitutes by default.
15087 Suppose you would like to fetch substitutes from @code{guix.example.org}
15088 in addition to @code{@value{SUBSTITUTE-SERVER}}. You will need to do
15089 two things: (1) add @code{guix.example.org} to @code{substitute-urls},
15090 and (2) authorize its signing key, having done appropriate checks
15091 (@pxref{Substitute Server Authorization}). The configuration below does
15095 (guix-configuration
15097 (append (list "https://guix.example.org")
15098 %default-substitute-urls))
15100 (append (list (local-file "./guix.example.org-key.pub"))
15101 %default-authorized-guix-keys)))
15104 This example assumes that the file @file{./guix.example.org-key.pub}
15105 contains the public key that @code{guix.example.org} uses to sign
15108 @item @code{max-silent-time} (default: @code{0})
15109 @itemx @code{timeout} (default: @code{0})
15110 The number of seconds of silence and the number of seconds of activity,
15111 respectively, after which a build process times out. A value of zero
15112 disables the timeout.
15114 @item @code{log-compression} (default: @code{'bzip2})
15115 The type of compression used for build logs---one of @code{gzip},
15116 @code{bzip2}, or @code{none}.
15118 @item @code{discover?} (default: @code{#f})
15119 Whether to discover substitute servers on the local network using mDNS
15122 @item @code{extra-options} (default: @code{'()})
15123 List of extra command-line options for @command{guix-daemon}.
15125 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
15126 File where @command{guix-daemon}'s standard output and standard error
15129 @cindex HTTP proxy, for @code{guix-daemon}
15130 @cindex proxy, for @code{guix-daemon} HTTP access
15131 @item @code{http-proxy} (default: @code{#f})
15132 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
15133 derivations and substitutes.
15135 It is also possible to change the daemon's proxy at run time through the
15136 @code{set-http-proxy} action, which restarts it:
15139 herd set-http-proxy guix-daemon http://localhost:8118
15142 To clear the proxy settings, run:
15145 herd set-http-proxy guix-daemon
15148 @item @code{tmpdir} (default: @code{#f})
15149 A directory path where the @command{guix-daemon} will perform builds.
15154 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
15155 Run @var{udev}, which populates the @file{/dev} directory dynamically.
15156 udev rules can be provided as a list of files through the @var{rules}
15157 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
15158 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
15159 creation of such rule files.
15161 The @command{herd rules udev} command, as root, returns the name of the
15162 directory containing all the active udev rules.
15165 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
15166 Return a udev-rule file named @var{file-name} containing the rules
15167 defined by the @var{contents} literal.
15169 In the following example, a rule for a USB device is defined to be
15170 stored in the file @file{90-usb-thing.rules}. The rule runs a script
15171 upon detecting a USB device with a given product identifier.
15174 (define %example-udev-rule
15176 "90-usb-thing.rules"
15177 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
15178 "ATTR@{product@}==\"Example\", "
15179 "RUN+=\"/path/to/script\"")))
15183 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
15184 [#:groups @var{groups}]
15185 Return a service that extends @code{udev-service-type } with @var{rules}
15186 and @code{account-service-type} with @var{groups} as system groups.
15187 This works by creating a singleton service type
15188 @code{@var{name}-udev-rules}, of which the returned service is an
15191 Here we show how it can be used to extend @code{udev-service-type} with the
15192 previously defined rule @code{%example-udev-rule}.
15198 (cons (udev-rules-service 'usb-thing %example-udev-rule)
15199 %desktop-services)))
15203 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
15204 Return a udev file named @var{file-name} containing the rules defined
15205 within @var{file}, a file-like object.
15207 The following example showcases how we can use an existing rule file.
15210 (use-modules (guix download) ;for url-fetch
15211 (guix packages) ;for origin
15214 (define %android-udev-rules
15216 "51-android-udev.rules"
15217 (let ((version "20170910"))
15220 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
15221 "android-udev-rules/" version "/51-android.rules"))
15223 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
15227 Additionally, Guix package definitions can be included in @var{rules} in
15228 order to extend the udev rules with the definitions found under their
15229 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
15230 @var{file->udev-rule} example, we could have used the
15231 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
15232 packages android)} module.
15234 The following example shows how to use the @var{android-udev-rules}
15235 package so that the Android tool @command{adb} can detect devices
15236 without root privileges. It also details how to create the
15237 @code{adbusers} group, which is required for the proper functioning of
15238 the rules defined within the @code{android-udev-rules} package. To
15239 create such a group, we must define it both as part of the
15240 @code{supplementary-groups} of our @code{user-account} declaration, as
15241 well as in the @var{groups} of the @code{udev-rules-service} procedure.
15244 (use-modules (gnu packages android) ;for android-udev-rules
15245 (gnu system shadow) ;for user-group
15250 (users (cons (user-account
15252 (supplementary-groups
15253 '("adbusers" ;for adb
15254 "wheel" "netdev" "audio" "video")))))
15257 (cons (udev-rules-service 'android android-udev-rules
15258 #:groups '("adbusers"))
15259 %desktop-services)))
15262 @defvr {Scheme Variable} urandom-seed-service-type
15263 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
15264 when rebooting. It also tries to seed @file{/dev/urandom} from
15265 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
15269 @defvr {Scheme Variable} %random-seed-file
15270 This is the name of the file where some random bytes are saved by
15271 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
15272 It defaults to @file{/var/lib/random-seed}.
15277 @defvr {Scheme Variable} gpm-service-type
15278 This is the type of the service that runs GPM, the @dfn{general-purpose
15279 mouse daemon}, which provides mouse support to the Linux console. GPM
15280 allows users to use the mouse in the console, notably to select, copy,
15283 The value for services of this type must be a @code{gpm-configuration}
15284 (see below). This service is not part of @code{%base-services}.
15287 @deftp {Data Type} gpm-configuration
15288 Data type representing the configuration of GPM.
15291 @item @code{options} (default: @code{%default-gpm-options})
15292 Command-line options passed to @command{gpm}. The default set of
15293 options instruct @command{gpm} to listen to mouse events on
15294 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
15297 @item @code{gpm} (default: @code{gpm})
15298 The GPM package to use.
15303 @anchor{guix-publish-service-type}
15304 @deffn {Scheme Variable} guix-publish-service-type
15305 This is the service type for @command{guix publish} (@pxref{Invoking
15306 guix publish}). Its value must be a @code{guix-publish-configuration}
15307 object, as described below.
15309 This assumes that @file{/etc/guix} already contains a signing key pair as
15310 created by @command{guix archive --generate-key} (@pxref{Invoking guix
15311 archive}). If that is not the case, the service will fail to start.
15314 @deftp {Data Type} guix-publish-configuration
15315 Data type representing the configuration of the @code{guix publish}
15319 @item @code{guix} (default: @code{guix})
15320 The Guix package to use.
15322 @item @code{port} (default: @code{80})
15323 The TCP port to listen for connections.
15325 @item @code{host} (default: @code{"localhost"})
15326 The host (and thus, network interface) to listen to. Use
15327 @code{"0.0.0.0"} to listen on all the network interfaces.
15329 @item @code{compression} (default: @code{'(("gzip" 3))})
15330 This is a list of compression method/level tuple used when compressing
15331 substitutes. For example, to compress all substitutes with @emph{both} lzip
15332 at level 7 and gzip at level 9, write:
15335 '(("lzip" 7) ("gzip" 9))
15338 Level 9 achieves the best compression ratio at the expense of increased CPU
15339 usage, whereas level 1 achieves fast compression.
15341 An empty list disables compression altogether.
15343 @item @code{nar-path} (default: @code{"nar"})
15344 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
15345 publish, @option{--nar-path}}, for details.
15347 @item @code{cache} (default: @code{#f})
15348 When it is @code{#f}, disable caching and instead generate archives on
15349 demand. Otherwise, this should be the name of a directory---e.g.,
15350 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
15351 archives and meta-data ready to be sent. @xref{Invoking guix publish,
15352 @option{--cache}}, for more information on the tradeoffs involved.
15354 @item @code{workers} (default: @code{#f})
15355 When it is an integer, this is the number of worker threads used for
15356 caching; when @code{#f}, the number of processors is used.
15357 @xref{Invoking guix publish, @option{--workers}}, for more information.
15359 @item @code{cache-bypass-threshold} (default: 10 MiB)
15360 When @code{cache} is true, this is the maximum size in bytes of a store
15361 item for which @command{guix publish} may bypass its cache in case of a
15362 cache miss. @xref{Invoking guix publish,
15363 @option{--cache-bypass-threshold}}, for more information.
15365 @item @code{ttl} (default: @code{#f})
15366 When it is an integer, this denotes the @dfn{time-to-live} in seconds
15367 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
15368 for more information.
15372 @anchor{rngd-service}
15373 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
15374 [#:device "/dev/hwrng"]
15375 Return a service that runs the @command{rngd} program from @var{rng-tools}
15376 to add @var{device} to the kernel's entropy pool. The service will fail if
15377 @var{device} does not exist.
15380 @anchor{pam-limits-service}
15381 @cindex session limits
15386 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
15388 Return a service that installs a configuration file for the
15389 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
15390 @code{pam_limits} module}. The procedure optionally takes a list of
15391 @code{pam-limits-entry} values, which can be used to specify
15392 @code{ulimit} limits and nice priority limits to user sessions.
15394 The following limits definition sets two hard and soft limits for all
15395 login sessions of users in the @code{realtime} group:
15398 (pam-limits-service
15400 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
15401 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
15404 The first entry increases the maximum realtime priority for
15405 non-privileged processes; the second entry lifts any restriction of the
15406 maximum address space that can be locked in memory. These settings are
15407 commonly used for real-time audio systems.
15410 @node Scheduled Job Execution
15411 @subsection Scheduled Job Execution
15415 @cindex scheduling jobs
15416 The @code{(gnu services mcron)} module provides an interface to
15417 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
15418 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
15419 Unix @command{cron} daemon; the main difference is that it is
15420 implemented in Guile Scheme, which provides a lot of flexibility when
15421 specifying the scheduling of jobs and their actions.
15423 The example below defines an operating system that runs the
15424 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
15425 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
15426 well as the @command{mkid} command on behalf of an unprivileged user
15427 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
15428 gexps to introduce job definitions that are passed to mcron
15429 (@pxref{G-Expressions}).
15432 (use-modules (guix) (gnu) (gnu services mcron))
15433 (use-package-modules base idutils)
15435 (define updatedb-job
15436 ;; Run 'updatedb' at 3AM every day. Here we write the
15437 ;; job's action as a Scheme procedure.
15438 #~(job '(next-hour '(3))
15440 (execl (string-append #$findutils "/bin/updatedb")
15442 "--prunepaths=/tmp /var/tmp /gnu/store"))))
15444 (define garbage-collector-job
15445 ;; Collect garbage 5 minutes after midnight every day.
15446 ;; The job's action is a shell command.
15447 #~(job "5 0 * * *" ;Vixie cron syntax
15450 (define idutils-job
15451 ;; Update the index database as user "charlie" at 12:15PM
15452 ;; and 19:15PM. This runs from the user's home directory.
15453 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
15454 (string-append #$idutils "/bin/mkid src")
15460 ;; %BASE-SERVICES already includes an instance of
15461 ;; 'mcron-service-type', which we extend with additional
15462 ;; jobs using 'simple-service'.
15463 (services (cons (simple-service 'my-cron-jobs
15465 (list garbage-collector-job
15471 For more complex jobs defined in Scheme where you need control over the top
15472 level, for instance to introduce a @code{use-modules} form, you can move your
15473 code to a separate program using the @code{program-file} procedure of the
15474 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
15478 (define %battery-alert-job
15479 ;; Beep when the battery percentage falls below %MIN-LEVEL.
15481 '(next-minute (range 0 60 1))
15483 "battery-alert.scm"
15484 (with-imported-modules (source-module-closure
15485 '((guix build utils)))
15487 (use-modules (guix build utils)
15490 (ice-9 textual-ports)
15493 (define %min-level 20)
15495 (setenv "LC_ALL" "C") ;ensure English output
15496 (and-let* ((input-pipe (open-pipe*
15498 #$(file-append acpi "/bin/acpi")))
15499 (output (get-string-all input-pipe))
15500 (m (string-match "Discharging, ([0-9]+)%" output))
15501 (level (string->number (match:substring m 1)))
15502 ((< level %min-level)))
15503 (format #t "warning: Battery level is low (~a%)~%" level)
15504 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
15507 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
15508 for more information on mcron job specifications. Below is the
15509 reference of the mcron service.
15511 On a running system, you can use the @code{schedule} action of the service to
15512 visualize the mcron jobs that will be executed next:
15515 # herd schedule mcron
15519 The example above lists the next five tasks that will be executed, but you can
15520 also specify the number of tasks to display:
15523 # herd schedule mcron 10
15526 @defvr {Scheme Variable} mcron-service-type
15527 This is the type of the @code{mcron} service, whose value is an
15528 @code{mcron-configuration} object.
15530 This service type can be the target of a service extension that provides
15531 it additional job specifications (@pxref{Service Composition}). In
15532 other words, it is possible to define services that provide additional
15536 @deftp {Data Type} mcron-configuration
15537 Data type representing the configuration of mcron.
15540 @item @code{mcron} (default: @var{mcron})
15541 The mcron package to use.
15544 This is a list of gexps (@pxref{G-Expressions}), where each gexp
15545 corresponds to an mcron job specification (@pxref{Syntax, mcron job
15546 specifications,, mcron, GNU@tie{}mcron}).
15552 @subsection Log Rotation
15555 @cindex log rotation
15557 Log files such as those found in @file{/var/log} tend to grow endlessly,
15558 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
15559 their contents in separate files, possibly compressed. The @code{(gnu
15560 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
15561 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
15563 This service is part of @code{%base-services}, and thus enabled by
15564 default, with the default settings, for commonly encountered log files.
15565 The example below shows how to extend it with an additional
15566 @dfn{rotation}, should you need to do that (usually, services that
15567 produce log files already take care of that):
15570 (use-modules (guix) (gnu))
15571 (use-service-modules admin)
15573 (define my-log-files
15574 ;; Log files that I want to rotate.
15575 '("/var/log/something.log" "/var/log/another.log"))
15579 (services (cons (simple-service 'rotate-my-stuff
15580 rottlog-service-type
15581 (list (log-rotation
15583 (files my-log-files))))
15587 @defvr {Scheme Variable} rottlog-service-type
15588 This is the type of the Rottlog service, whose value is a
15589 @code{rottlog-configuration} object.
15591 Other services can extend this one with new @code{log-rotation} objects
15592 (see below), thereby augmenting the set of files to be rotated.
15594 This service type can define mcron jobs (@pxref{Scheduled Job
15595 Execution}) to run the rottlog service.
15598 @deftp {Data Type} rottlog-configuration
15599 Data type representing the configuration of rottlog.
15602 @item @code{rottlog} (default: @code{rottlog})
15603 The Rottlog package to use.
15605 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
15606 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
15607 rottlog, GNU Rot[t]log Manual}).
15609 @item @code{rotations} (default: @code{%default-rotations})
15610 A list of @code{log-rotation} objects as defined below.
15613 This is a list of gexps where each gexp corresponds to an mcron job
15614 specification (@pxref{Scheduled Job Execution}).
15618 @deftp {Data Type} log-rotation
15619 Data type representing the rotation of a group of log files.
15621 Taking an example from the Rottlog manual (@pxref{Period Related File
15622 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
15628 (files '("/var/log/apache/*"))
15629 (options '("storedir apache-archives"
15635 The list of fields is as follows:
15638 @item @code{frequency} (default: @code{'weekly})
15639 The log rotation frequency, a symbol.
15642 The list of files or file glob patterns to rotate.
15644 @item @code{options} (default: @code{'()})
15645 The list of rottlog options for this rotation (@pxref{Configuration
15646 parameters,,, rottlog, GNU Rot[t]lg Manual}).
15648 @item @code{post-rotate} (default: @code{#f})
15649 Either @code{#f} or a gexp to execute once the rotation has completed.
15653 @defvr {Scheme Variable} %default-rotations
15654 Specifies weekly rotation of @code{%rotated-files} and of
15655 @file{/var/log/guix-daemon.log}.
15658 @defvr {Scheme Variable} %rotated-files
15659 The list of syslog-controlled files to be rotated. By default it is:
15660 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
15661 "/var/log/maillog")}.
15664 @node Networking Services
15665 @subsection Networking Services
15667 The @code{(gnu services networking)} module provides services to configure
15668 the network interface.
15670 @cindex DHCP, networking service
15671 @defvr {Scheme Variable} dhcp-client-service-type
15672 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
15673 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
15674 is the DHCP client package to use, @code{isc-dhcp} by default.
15677 @deffn {Scheme Procedure} dhcpd-service-type
15678 This type defines a service that runs a DHCP daemon. To create a
15679 service of this type, you must supply a @code{<dhcpd-configuration>}.
15683 (service dhcpd-service-type
15684 (dhcpd-configuration
15685 (config-file (local-file "my-dhcpd.conf"))
15686 (interfaces '("enp0s25"))))
15690 @deftp {Data Type} dhcpd-configuration
15692 @item @code{package} (default: @code{isc-dhcp})
15693 The package that provides the DHCP daemon. This package is expected to
15694 provide the daemon at @file{sbin/dhcpd} relative to its output
15695 directory. The default package is the
15696 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
15697 @item @code{config-file} (default: @code{#f})
15698 The configuration file to use. This is required. It will be passed to
15699 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
15700 object (@pxref{G-Expressions, file-like objects}). See @code{man
15701 dhcpd.conf} for details on the configuration file syntax.
15702 @item @code{version} (default: @code{"4"})
15703 The DHCP version to use. The ISC DHCP server supports the values ``4'',
15704 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
15705 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
15707 @item @code{run-directory} (default: @code{"/run/dhcpd"})
15708 The run directory to use. At service activation time, this directory
15709 will be created if it does not exist.
15710 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
15711 The PID file to use. This corresponds to the @code{-pf} option of
15712 @code{dhcpd}. See @code{man dhcpd} for details.
15713 @item @code{interfaces} (default: @code{'()})
15714 The names of the network interfaces on which dhcpd should listen for
15715 broadcasts. If this list is not empty, then its elements (which must be
15716 strings) will be appended to the @code{dhcpd} invocation when starting
15717 the daemon. It may not be necessary to explicitly specify any
15718 interfaces here; see @code{man dhcpd} for details.
15722 @defvr {Scheme Variable} static-networking-service-type
15723 This is the type for statically-configured network interfaces.
15724 @c TODO Document <static-networking> data structures.
15727 @deffn {Scheme Procedure} static-networking-service @var{interface} @var{ip} @
15728 [#:netmask #f] [#:gateway #f] [#:name-servers @code{'()}] @
15729 [#:requirement @code{'(udev)}]
15730 Return a service that starts @var{interface} with address @var{ip}. If
15731 @var{netmask} is true, use it as the network mask. If @var{gateway} is true,
15732 it must be a string specifying the default network gateway. @var{requirement}
15733 can be used to declare a dependency on another service before configuring the
15736 This procedure can be called several times, one for each network
15737 interface of interest. Behind the scenes what it does is extend
15738 @code{static-networking-service-type} with additional network interfaces
15744 (static-networking-service "eno1" "192.168.1.82"
15745 #:gateway "192.168.1.2"
15746 #:name-servers '("192.168.1.2"))
15753 @cindex network management
15754 @deffn {Scheme Procedure} wicd-service [#:wicd @var{wicd}]
15755 Return a service that runs @url{https://launchpad.net/wicd,Wicd}, a network
15756 management daemon that aims to simplify wired and wireless networking.
15758 This service adds the @var{wicd} package to the global profile, providing
15759 several commands to interact with the daemon and configure networking:
15760 @command{wicd-client}, a graphical user interface, and the @command{wicd-cli}
15761 and @command{wicd-curses} user interfaces.
15764 @cindex ModemManager
15766 @defvr {Scheme Variable} modem-manager-service-type
15767 This is the service type for the
15768 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
15769 service. The value for this service type is a
15770 @code{modem-manager-configuration} record.
15772 This service is part of @code{%desktop-services} (@pxref{Desktop
15776 @deftp {Data Type} modem-manager-configuration
15777 Data type representing the configuration of ModemManager.
15780 @item @code{modem-manager} (default: @code{modem-manager})
15781 The ModemManager package to use.
15786 @cindex USB_ModeSwitch
15787 @cindex Modeswitching
15789 @defvr {Scheme Variable} usb-modeswitch-service-type
15790 This is the service type for the
15791 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch} service. The
15792 value for this service type is a @code{usb-modeswitch-configuration} record.
15794 When plugged in, some USB modems (and other USB devices) initially present
15795 themselves as a read-only storage medium and not as a modem. They need to be
15796 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
15797 installs udev rules to automatically modeswitch these devices when they are
15800 This service is part of @code{%desktop-services} (@pxref{Desktop
15804 @deftp {Data Type} usb-modeswitch-configuration
15805 Data type representing the configuration of USB_ModeSwitch.
15808 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
15809 The USB_ModeSwitch package providing the binaries for modeswitching.
15811 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
15812 The package providing the device data and udev rules file used by
15815 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
15816 Which config file to use for the USB_ModeSwitch dispatcher. By default the
15817 config file shipped with USB_ModeSwitch is used which disables logging to
15818 @file{/var/log} among other default settings. If set to @code{#f}, no config
15824 @cindex NetworkManager
15826 @defvr {Scheme Variable} network-manager-service-type
15827 This is the service type for the
15828 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
15829 service. The value for this service type is a
15830 @code{network-manager-configuration} record.
15832 This service is part of @code{%desktop-services} (@pxref{Desktop
15836 @deftp {Data Type} network-manager-configuration
15837 Data type representing the configuration of NetworkManager.
15840 @item @code{network-manager} (default: @code{network-manager})
15841 The NetworkManager package to use.
15843 @item @code{dns} (default: @code{"default"})
15844 Processing mode for DNS, which affects how NetworkManager uses the
15845 @code{resolv.conf} configuration file.
15849 NetworkManager will update @code{resolv.conf} to reflect the nameservers
15850 provided by currently active connections.
15853 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
15854 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
15855 then update @code{resolv.conf} to point to the local nameserver.
15857 With this setting, you can share your network connection. For example when
15858 you want to share your network connection to another laptop @i{via} an
15859 Ethernet cable, you can open @command{nm-connection-editor} and configure the
15860 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
15861 and reestablish the connection (or reboot).
15863 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
15864 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
15865 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
15866 browser on your host system, or connect to the VM @i{via} SSH
15867 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
15868 host-to-guest connection, run this command once:
15871 nmcli connection add type tun \
15872 connection.interface-name tap0 \
15873 tun.mode tap tun.owner $(id -u) \
15874 ipv4.method shared \
15875 ipv4.addresses 172.28.112.1/24
15878 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
15879 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
15880 @command{qemu-system-...}.
15883 NetworkManager will not modify @code{resolv.conf}.
15886 @item @code{vpn-plugins} (default: @code{'()})
15887 This is the list of available plugins for virtual private networks
15888 (VPNs). An example of this is the @code{network-manager-openvpn}
15889 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
15895 @deffn {Scheme Variable} connman-service-type
15896 This is the service type to run @url{https://01.org/connman,Connman},
15897 a network connection manager.
15899 Its value must be an
15900 @code{connman-configuration} record as in this example:
15903 (service connman-service-type
15904 (connman-configuration
15905 (disable-vpn? #t)))
15908 See below for details about @code{connman-configuration}.
15911 @deftp {Data Type} connman-configuration
15912 Data Type representing the configuration of connman.
15915 @item @code{connman} (default: @var{connman})
15916 The connman package to use.
15918 @item @code{disable-vpn?} (default: @code{#f})
15919 When true, disable connman's vpn plugin.
15923 @cindex WPA Supplicant
15924 @defvr {Scheme Variable} wpa-supplicant-service-type
15925 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
15926 supplicant}, an authentication daemon required to authenticate against
15927 encrypted WiFi or ethernet networks.
15930 @deftp {Data Type} wpa-supplicant-configuration
15931 Data type representing the configuration of WPA Supplicant.
15933 It takes the following parameters:
15936 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
15937 The WPA Supplicant package to use.
15939 @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
15940 List of services that should be started before WPA Supplicant starts.
15942 @item @code{dbus?} (default: @code{#t})
15943 Whether to listen for requests on D-Bus.
15945 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
15946 Where to store the PID file.
15948 @item @code{interface} (default: @code{#f})
15949 If this is set, it must specify the name of a network interface that
15950 WPA supplicant will control.
15952 @item @code{config-file} (default: @code{#f})
15953 Optional configuration file to use.
15955 @item @code{extra-options} (default: @code{'()})
15956 List of additional command-line arguments to pass to the daemon.
15960 @cindex hostapd service, for Wi-Fi access points
15961 @cindex Wi-Fi access points, hostapd service
15962 @defvr {Scheme Variable} hostapd-service-type
15963 This is the service type to run the @uref{https://w1.fi/hostapd/,
15964 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
15965 authentication servers. Its associated value must be a
15966 @code{hostapd-configuration} as shown below:
15969 ;; Use wlan1 to run the access point for "My Network".
15970 (service hostapd-service-type
15971 (hostapd-configuration
15972 (interface "wlan1")
15973 (ssid "My Network")
15978 @deftp {Data Type} hostapd-configuration
15979 This data type represents the configuration of the hostapd service, with
15980 the following fields:
15983 @item @code{package} (default: @code{hostapd})
15984 The hostapd package to use.
15986 @item @code{interface} (default: @code{"wlan0"})
15987 The network interface to run the WiFi access point.
15990 The SSID (@dfn{service set identifier}), a string that identifies this
15993 @item @code{broadcast-ssid?} (default: @code{#t})
15994 Whether to broadcast this SSID.
15996 @item @code{channel} (default: @code{1})
15997 The WiFi channel to use.
15999 @item @code{driver} (default: @code{"nl80211"})
16000 The driver interface type. @code{"nl80211"} is used with all Linux
16001 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
16002 RADIUS server that does # not control any wireless/wired driver.
16004 @item @code{extra-settings} (default: @code{""})
16005 Extra settings to append as-is to the hostapd configuration file. See
16006 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
16007 configuration file reference.
16011 @defvr {Scheme Variable} simulated-wifi-service-type
16012 This is the type of a service to simulate WiFi networking, which can be
16013 useful in virtual machines for testing purposes. The service loads the
16015 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
16016 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
16017 network that can be seen on @code{wlan0}, by default.
16019 The service's value is a @code{hostapd-configuration} record.
16023 @defvr {Scheme Variable} iptables-service-type
16024 This is the service type to set up an iptables configuration. iptables is a
16025 packet filtering framework supported by the Linux kernel. This service
16026 supports configuring iptables for both IPv4 and IPv6. A simple example
16027 configuration rejecting all incoming connections except those to the ssh port
16031 (service iptables-service-type
16032 (iptables-configuration
16033 (ipv4-rules (plain-file "iptables.rules" "*filter
16037 -A INPUT -p tcp --dport 22 -j ACCEPT
16038 -A INPUT -j REJECT --reject-with icmp-port-unreachable
16041 (ipv6-rules (plain-file "ip6tables.rules" "*filter
16045 -A INPUT -p tcp --dport 22 -j ACCEPT
16046 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
16052 @deftp {Data Type} iptables-configuration
16053 The data type representing the configuration of iptables.
16056 @item @code{iptables} (default: @code{iptables})
16057 The iptables package that provides @code{iptables-restore} and
16058 @code{ip6tables-restore}.
16059 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
16060 The iptables rules to use. It will be passed to @code{iptables-restore}.
16061 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
16063 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
16064 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
16065 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
16071 @defvr {Scheme Variable} nftables-service-type
16072 This is the service type to set up a nftables configuration. nftables is a
16073 netfilter project that aims to replace the existing iptables, ip6tables,
16074 arptables and ebtables framework. It provides a new packet filtering
16075 framework, a new user-space utility @command{nft}, and a compatibility layer
16076 for iptables. This service comes with a default ruleset
16077 @code{%default-nftables-ruleset} that rejecting all incomming connections
16078 except those to the ssh port 22. To use it, simply write:
16081 (service nftables-service-type)
16085 @deftp {Data Type} nftables-configuration
16086 The data type representing the configuration of nftables.
16089 @item @code{package} (default: @code{nftables})
16090 The nftables package that provides @command{nft}.
16091 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
16092 The nftables ruleset to use. This may be any ``file-like'' object
16093 (@pxref{G-Expressions, file-like objects}).
16097 @cindex NTP (Network Time Protocol), service
16098 @cindex ntpd, service for the Network Time Protocol daemon
16099 @cindex real time clock
16100 @defvr {Scheme Variable} ntp-service-type
16101 This is the type of the service running the @uref{https://www.ntp.org,
16102 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
16103 system clock synchronized with that of the specified NTP servers.
16105 The value of this service is an @code{ntpd-configuration} object, as described
16109 @deftp {Data Type} ntp-configuration
16110 This is the data type for the NTP service configuration.
16113 @item @code{servers} (default: @code{%ntp-servers})
16114 This is the list of servers (@code{<ntp-server>} records) with which
16115 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
16118 @item @code{allow-large-adjustment?} (default: @code{#t})
16119 This determines whether @command{ntpd} is allowed to make an initial
16120 adjustment of more than 1,000 seconds.
16122 @item @code{ntp} (default: @code{ntp})
16123 The NTP package to use.
16127 @defvr {Scheme Variable} %ntp-servers
16128 List of host names used as the default NTP servers. These are servers of the
16129 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
16132 @deftp {Data Type} ntp-server
16133 The data type representing the configuration of a NTP server.
16136 @item @code{type} (default: @code{'server})
16137 The type of the NTP server, given as a symbol. One of @code{'pool},
16138 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
16140 @item @code{address}
16141 The address of the server, as a string.
16143 @item @code{options}
16144 NTPD options to use with that specific server, given as a list of option names
16145 and/or of option names and values tuples. The following example define a server
16146 to use with the options @option{iburst} and @option{prefer}, as well as
16147 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
16152 (address "some.ntp.server.org")
16153 (options `(iburst (version 3) (maxpoll 16) prefer))))
16159 @deffn {Scheme Procedure} openntpd-service-type
16160 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
16161 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
16162 clock synchronized with that of the given servers.
16166 openntpd-service-type
16167 (openntpd-configuration
16168 (listen-on '("127.0.0.1" "::1"))
16169 (sensor '("udcf0 correction 70000"))
16170 (constraint-from '("www.gnu.org"))
16171 (constraints-from '("https://www.google.com/"))
16172 (allow-large-adjustment? #t)))
16177 @defvr {Scheme Variable} %openntpd-servers
16178 This variable is a list of the server addresses defined in
16179 @code{%ntp-servers}.
16182 @deftp {Data Type} openntpd-configuration
16184 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
16185 The openntpd executable to use.
16186 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
16187 A list of local IP addresses or hostnames the ntpd daemon should listen on.
16188 @item @code{query-from} (default: @code{'()})
16189 A list of local IP address the ntpd daemon should use for outgoing queries.
16190 @item @code{sensor} (default: @code{'()})
16191 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
16192 will listen to each sensor that actually exists and ignore non-existent ones.
16193 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
16195 @item @code{server} (default: @code{'()})
16196 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
16197 @item @code{servers} (default: @code{%openntp-servers})
16198 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
16199 @item @code{constraint-from} (default: @code{'()})
16200 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
16201 This time information is not used for precision but acts as an authenticated
16202 constraint, thereby reducing the impact of unauthenticated NTP
16203 man-in-the-middle attacks.
16204 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
16206 @item @code{constraints-from} (default: @code{'()})
16207 As with constraint from, specify a list of URLs, IP addresses or hostnames of
16208 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
16209 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
16210 @item @code{allow-large-adjustment?} (default: @code{#f})
16211 Determines if @code{ntpd} is allowed to make an initial adjustment of more
16217 @deffn {Scheme variable} inetd-service-type
16218 This service runs the @command{inetd} (@pxref{inetd invocation,,,
16219 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
16220 connections on internet sockets, and lazily starts the specified server
16221 program when a connection is made on one of these sockets.
16223 The value of this service is an @code{inetd-configuration} object. The
16224 following example configures the @command{inetd} daemon to provide the
16225 built-in @command{echo} service, as well as an smtp service which
16226 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
16227 gateway @code{hostname}:
16232 (inetd-configuration
16236 (socket-type 'stream)
16243 (socket-type 'stream)
16247 (program (file-append openssh "/bin/ssh"))
16249 '("ssh" "-qT" "-i" "/path/to/ssh_key"
16250 "-W" "smtp-server:25" "user@@hostname")))))))
16253 See below for more details about @code{inetd-configuration}.
16256 @deftp {Data Type} inetd-configuration
16257 Data type representing the configuration of @command{inetd}.
16260 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
16261 The @command{inetd} executable to use.
16263 @item @code{entries} (default: @code{'()})
16264 A list of @command{inetd} service entries. Each entry should be created
16265 by the @code{inetd-entry} constructor.
16269 @deftp {Data Type} inetd-entry
16270 Data type representing an entry in the @command{inetd} configuration.
16271 Each entry corresponds to a socket where @command{inetd} will listen for
16275 @item @code{node} (default: @code{#f})
16276 Optional string, a comma-separated list of local addresses
16277 @command{inetd} should use when listening for this service.
16278 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
16279 description of all options.
16281 A string, the name must correspond to an entry in @code{/etc/services}.
16282 @item @code{socket-type}
16283 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
16285 @item @code{protocol}
16286 A string, must correspond to an entry in @code{/etc/protocols}.
16287 @item @code{wait?} (default: @code{#t})
16288 Whether @command{inetd} should wait for the server to exit before
16289 listening to new service requests.
16291 A string containing the user (and, optionally, group) name of the user
16292 as whom the server should run. The group name can be specified in a
16293 suffix, separated by a colon or period, i.e.@: @code{"user"},
16294 @code{"user:group"} or @code{"user.group"}.
16295 @item @code{program} (default: @code{"internal"})
16296 The server program which will serve the requests, or @code{"internal"}
16297 if @command{inetd} should use a built-in service.
16298 @item @code{arguments} (default: @code{'()})
16299 A list strings or file-like objects, which are the server program's
16300 arguments, starting with the zeroth argument, i.e.@: the name of the
16301 program itself. For @command{inetd}'s internal services, this entry
16302 must be @code{'()} or @code{'("internal")}.
16305 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
16306 detailed discussion of each configuration field.
16310 @defvr {Scheme Variable} tor-service-type
16311 This is the type for a service that runs the @uref{https://torproject.org,
16312 Tor} anonymous networking daemon. The service is configured using a
16313 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
16314 @code{tor} unprivileged user, which is a member of the @code{tor} group.
16318 @deftp {Data Type} tor-configuration
16320 @item @code{tor} (default: @code{tor})
16321 The package that provides the Tor daemon. This package is expected to provide
16322 the daemon at @file{bin/tor} relative to its output directory. The default
16323 package is the @uref{https://www.torproject.org, Tor Project's}
16326 @item @code{config-file} (default: @code{(plain-file "empty" "")})
16327 The configuration file to use. It will be appended to a default configuration
16328 file, and the final configuration file will be passed to @code{tor} via its
16329 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
16330 file-like objects}). See @code{man tor} for details on the configuration file
16333 @item @code{hidden-services} (default: @code{'()})
16334 The list of @code{<hidden-service>} records to use. For any hidden service
16335 you include in this list, appropriate configuration to enable the hidden
16336 service will be automatically added to the default configuration file. You
16337 may conveniently create @code{<hidden-service>} records using the
16338 @code{tor-hidden-service} procedure described below.
16340 @item @code{socks-socket-type} (default: @code{'tcp})
16341 The default socket type that Tor should use for its SOCKS socket. This must
16342 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
16343 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
16344 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
16345 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
16348 If you want to customize the SOCKS socket in more detail, leave
16349 @code{socks-socket-type} at its default value of @code{'tcp} and use
16350 @code{config-file} to override the default by providing your own
16351 @code{SocksPort} option.
16355 @cindex hidden service
16356 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
16357 Define a new Tor @dfn{hidden service} called @var{name} and implementing
16358 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
16361 '((22 "127.0.0.1:22")
16362 (80 "127.0.0.1:8080"))
16365 In this example, port 22 of the hidden service is mapped to local port 22, and
16366 port 80 is mapped to local port 8080.
16368 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
16369 the @file{hostname} file contains the @code{.onion} host name for the hidden
16372 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
16373 project's documentation} for more information.
16376 The @code{(gnu services rsync)} module provides the following services:
16378 You might want an rsync daemon if you have files that you want available
16379 so anyone (or just yourself) can download existing files or upload new
16382 @deffn {Scheme Variable} rsync-service-type
16383 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
16384 The value for this service type is a
16385 @command{rsync-configuration} record as in this example:
16388 (service rsync-service-type)
16391 See below for details about @code{rsync-configuration}.
16394 @deftp {Data Type} rsync-configuration
16395 Data type representing the configuration for @code{rsync-service}.
16398 @item @code{package} (default: @var{rsync})
16399 @code{rsync} package to use.
16401 @item @code{port-number} (default: @code{873})
16402 TCP port on which @command{rsync} listens for incoming connections. If port
16403 is less than @code{1024} @command{rsync} needs to be started as the
16404 @code{root} user and group.
16406 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
16407 Name of the file where @command{rsync} writes its PID.
16409 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
16410 Name of the file where @command{rsync} writes its lock file.
16412 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
16413 Name of the file where @command{rsync} writes its log file.
16415 @item @code{use-chroot?} (default: @var{#t})
16416 Whether to use chroot for @command{rsync} shared directory.
16418 @item @code{share-path} (default: @file{/srv/rsync})
16419 Location of the @command{rsync} shared directory.
16421 @item @code{share-comment} (default: @code{"Rsync share"})
16422 Comment of the @command{rsync} shared directory.
16424 @item @code{read-only?} (default: @var{#f})
16425 Read-write permissions to shared directory.
16427 @item @code{timeout} (default: @code{300})
16428 I/O timeout in seconds.
16430 @item @code{user} (default: @var{"root"})
16431 Owner of the @code{rsync} process.
16433 @item @code{group} (default: @var{"root"})
16434 Group of the @code{rsync} process.
16436 @item @code{uid} (default: @var{"rsyncd"})
16437 User name or user ID that file transfers to and from that module should take
16438 place as when the daemon was run as @code{root}.
16440 @item @code{gid} (default: @var{"rsyncd"})
16441 Group name or group ID that will be used when accessing the module.
16446 Furthermore, @code{(gnu services ssh)} provides the following services.
16450 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
16451 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
16452 [#:allow-empty-passwords? #f] [#:root-login? #f] @
16453 [#:syslog-output? #t] [#:x11-forwarding? #t] @
16454 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
16455 [#:public-key-authentication? #t] [#:initialize? #t]
16456 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
16457 @var{host-key} must designate a file containing the host key, and readable
16460 When @var{daemonic?} is true, @command{lshd} will detach from the
16461 controlling terminal and log its output to syslogd, unless one sets
16462 @var{syslog-output?} to false. Obviously, it also makes lsh-service
16463 depend on existence of syslogd service. When @var{pid-file?} is true,
16464 @command{lshd} writes its PID to the file called @var{pid-file}.
16466 When @var{initialize?} is true, automatically create the seed and host key
16467 upon service activation if they do not exist yet. This may take long and
16468 require interaction.
16470 When @var{initialize?} is false, it is up to the user to initialize the
16471 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
16472 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
16473 basics,,, lsh, LSH Manual}).
16475 When @var{interfaces} is empty, lshd listens for connections on all the
16476 network interfaces; otherwise, @var{interfaces} must be a list of host names
16479 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
16480 passwords, and @var{root-login?} specifies whether to accept log-ins as
16483 The other options should be self-descriptive.
16488 @deffn {Scheme Variable} openssh-service-type
16489 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
16490 shell daemon, @command{sshd}. Its value must be an
16491 @code{openssh-configuration} record as in this example:
16494 (service openssh-service-type
16495 (openssh-configuration
16496 (x11-forwarding? #t)
16497 (permit-root-login 'without-password)
16499 `(("alice" ,(local-file "alice.pub"))
16500 ("bob" ,(local-file "bob.pub"))))))
16503 See below for details about @code{openssh-configuration}.
16505 This service can be extended with extra authorized keys, as in this
16509 (service-extension openssh-service-type
16510 (const `(("charlie"
16511 ,(local-file "charlie.pub")))))
16515 @deftp {Data Type} openssh-configuration
16516 This is the configuration record for OpenSSH's @command{sshd}.
16519 @item @code{openssh} (default @var{openssh})
16520 The Openssh package to use.
16522 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
16523 Name of the file where @command{sshd} writes its PID.
16525 @item @code{port-number} (default: @code{22})
16526 TCP port on which @command{sshd} listens for incoming connections.
16528 @item @code{permit-root-login} (default: @code{#f})
16529 This field determines whether and when to allow logins as root. If
16530 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
16531 If it's the symbol @code{'without-password}, then root logins are
16532 permitted but not with password-based authentication.
16534 @item @code{allow-empty-passwords?} (default: @code{#f})
16535 When true, users with empty passwords may log in. When false, they may
16538 @item @code{password-authentication?} (default: @code{#t})
16539 When true, users may log in with their password. When false, they have
16540 other authentication methods.
16542 @item @code{public-key-authentication?} (default: @code{#t})
16543 When true, users may log in using public key authentication. When
16544 false, users have to use other authentication method.
16546 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
16547 This is used only by protocol version 2.
16549 @item @code{x11-forwarding?} (default: @code{#f})
16550 When true, forwarding of X11 graphical client connections is
16551 enabled---in other words, @command{ssh} options @option{-X} and
16552 @option{-Y} will work.
16554 @item @code{allow-agent-forwarding?} (default: @code{#t})
16555 Whether to allow agent forwarding.
16557 @item @code{allow-tcp-forwarding?} (default: @code{#t})
16558 Whether to allow TCP forwarding.
16560 @item @code{gateway-ports?} (default: @code{#f})
16561 Whether to allow gateway ports.
16563 @item @code{challenge-response-authentication?} (default: @code{#f})
16564 Specifies whether challenge response authentication is allowed (e.g.@: via
16567 @item @code{use-pam?} (default: @code{#t})
16568 Enables the Pluggable Authentication Module interface. If set to
16569 @code{#t}, this will enable PAM authentication using
16570 @code{challenge-response-authentication?} and
16571 @code{password-authentication?}, in addition to PAM account and session
16572 module processing for all authentication types.
16574 Because PAM challenge response authentication usually serves an
16575 equivalent role to password authentication, you should disable either
16576 @code{challenge-response-authentication?} or
16577 @code{password-authentication?}.
16579 @item @code{print-last-log?} (default: @code{#t})
16580 Specifies whether @command{sshd} should print the date and time of the
16581 last user login when a user logs in interactively.
16583 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
16584 Configures external subsystems (e.g.@: file transfer daemon).
16586 This is a list of two-element lists, each of which containing the
16587 subsystem name and a command (with optional arguments) to execute upon
16590 The command @command{internal-sftp} implements an in-process SFTP
16591 server. Alternatively, one can specify the @command{sftp-server} command:
16593 (service openssh-service-type
16594 (openssh-configuration
16596 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
16599 @item @code{accepted-environment} (default: @code{'()})
16600 List of strings describing which environment variables may be exported.
16602 Each string gets on its own line. See the @code{AcceptEnv} option in
16603 @code{man sshd_config}.
16605 This example allows ssh-clients to export the @env{COLORTERM} variable.
16606 It is set by terminal emulators, which support colors. You can use it in
16607 your shell's resource file to enable colors for the prompt and commands
16608 if this variable is set.
16611 (service openssh-service-type
16612 (openssh-configuration
16613 (accepted-environment '("COLORTERM"))))
16616 @item @code{authorized-keys} (default: @code{'()})
16617 @cindex authorized keys, SSH
16618 @cindex SSH authorized keys
16619 This is the list of authorized keys. Each element of the list is a user
16620 name followed by one or more file-like objects that represent SSH public
16624 (openssh-configuration
16626 `(("rekado" ,(local-file "rekado.pub"))
16627 ("chris" ,(local-file "chris.pub"))
16628 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
16632 registers the specified public keys for user accounts @code{rekado},
16633 @code{chris}, and @code{root}.
16635 Additional authorized keys can be specified @i{via}
16636 @code{service-extension}.
16638 Note that this does @emph{not} interfere with the use of
16639 @file{~/.ssh/authorized_keys}.
16641 @item @code{log-level} (default: @code{'info})
16642 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
16643 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
16644 page for @file{sshd_config} for the full list of level names.
16646 @item @code{extra-content} (default: @code{""})
16647 This field can be used to append arbitrary text to the configuration file. It
16648 is especially useful for elaborate configurations that cannot be expressed
16649 otherwise. This configuration, for example, would generally disable root
16650 logins, but permit them from one specific IP address:
16653 (openssh-configuration
16655 Match Address 192.168.0.1
16656 PermitRootLogin yes"))
16662 @deffn {Scheme Procedure} dropbear-service [@var{config}]
16663 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
16664 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
16667 For example, to specify a Dropbear service listening on port 1234, add
16668 this call to the operating system's @code{services} field:
16671 (dropbear-service (dropbear-configuration
16672 (port-number 1234)))
16676 @deftp {Data Type} dropbear-configuration
16677 This data type represents the configuration of a Dropbear SSH daemon.
16680 @item @code{dropbear} (default: @var{dropbear})
16681 The Dropbear package to use.
16683 @item @code{port-number} (default: 22)
16684 The TCP port where the daemon waits for incoming connections.
16686 @item @code{syslog-output?} (default: @code{#t})
16687 Whether to enable syslog output.
16689 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
16690 File name of the daemon's PID file.
16692 @item @code{root-login?} (default: @code{#f})
16693 Whether to allow @code{root} logins.
16695 @item @code{allow-empty-passwords?} (default: @code{#f})
16696 Whether to allow empty passwords.
16698 @item @code{password-authentication?} (default: @code{#t})
16699 Whether to enable password-based authentication.
16704 @deffn {Scheme Variable} autossh-service-type
16705 This is the type for the @uref{https://www.harding.motd.ca/autossh,
16706 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
16707 restarting it as necessary should it die or stop passing traffic.
16708 AutoSSH can be run manually from the command-line by passing arguments
16709 to the binary @command{autossh} from the package @code{autossh}, but it
16710 can also be run as a Guix service. This latter use case is documented
16713 AutoSSH can be used to forward local traffic to a remote machine using
16714 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
16717 For example, to specify a service running autossh as the user
16718 @code{pino} and forwarding all local connections to port @code{8081} to
16719 @code{remote:8081} using an SSH tunnel, add this call to the operating
16720 system's @code{services} field:
16723 (service autossh-service-type
16724 (autossh-configuration
16726 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
16730 @deftp {Data Type} autossh-configuration
16731 This data type represents the configuration of an AutoSSH service.
16735 @item @code{user} (default @code{"autossh"})
16736 The user as which the AutoSSH service is to be run.
16737 This assumes that the specified user exists.
16739 @item @code{poll} (default @code{600})
16740 Specifies the connection poll time in seconds.
16742 @item @code{first-poll} (default @code{#f})
16743 Specifies how many seconds AutoSSH waits before the first connection
16744 test. After this first test, polling is resumed at the pace defined in
16745 @code{poll}. When set to @code{#f}, the first poll is not treated
16746 specially and will also use the connection poll specified in
16749 @item @code{gate-time} (default @code{30})
16750 Specifies how many seconds an SSH connection must be active before it is
16751 considered successful.
16753 @item @code{log-level} (default @code{1})
16754 The log level, corresponding to the levels used by syslog---so @code{0}
16755 is the most silent while @code{7} is the chattiest.
16757 @item @code{max-start} (default @code{#f})
16758 The maximum number of times SSH may be (re)started before AutoSSH exits.
16759 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
16761 @item @code{message} (default @code{""})
16762 The message to append to the echo message sent when testing connections.
16764 @item @code{port} (default @code{"0"})
16765 The ports used for monitoring the connection. When set to @code{"0"},
16766 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
16767 a positive integer, ports @var{n} and @var{n}+1 are used for
16768 monitoring the connection, such that port @var{n} is the base
16769 monitoring port and @code{n+1} is the echo port. When set to
16770 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
16771 integers, the ports @var{n} and @var{m} are used for monitoring the
16772 connection, such that port @var{n} is the base monitoring port and
16773 @var{m} is the echo port.
16775 @item @code{ssh-options} (default @code{'()})
16776 The list of command-line arguments to pass to @command{ssh} when it is
16777 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
16778 may cause undefined behaviour.
16784 @deffn {Scheme Variable} webssh-service-type
16785 This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
16786 program that runs a web SSH client. WebSSH can be run manually from the
16787 command-line by passing arguments to the binary @command{wssh} from the
16788 package @code{webssh}, but it can also be run as a Guix service. This
16789 latter use case is documented here.
16791 For example, to specify a service running WebSSH on loopback interface
16792 on port @code{8888} with reject policy with a list of allowed to
16793 connection hosts, and NGINX as a reverse-proxy to this service listening
16794 for HTTPS connection, add this call to the operating system's
16795 @code{services} field:
16798 (service webssh-service-type
16799 (webssh-configuration (address "127.0.0.1")
16802 (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
16803 "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
16805 (service nginx-service-type
16806 (nginx-configuration
16809 (nginx-server-configuration
16810 (inherit %webssh-configuration-nginx)
16811 (server-name '("webssh.example.com"))
16812 (listen '("443 ssl"))
16813 (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
16814 (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
16816 (cons (nginx-location-configuration
16817 (uri "/.well-known")
16818 (body '("root /var/www;")))
16819 (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
16823 @deftp {Data Type} webssh-configuration
16824 Data type representing the configuration for @code{webssh-service}.
16827 @item @code{package} (default: @var{webssh})
16828 @code{webssh} package to use.
16830 @item @code{user-name} (default: @var{"webssh"})
16831 User name or user ID that file transfers to and from that module should take
16834 @item @code{group-name} (default: @var{"webssh"})
16835 Group name or group ID that will be used when accessing the module.
16837 @item @code{address} (default: @var{#f})
16838 IP address on which @command{webssh} listens for incoming connections.
16840 @item @code{port} (default: @var{8888})
16841 TCP port on which @command{webssh} listens for incoming connections.
16843 @item @code{policy} (default: @var{#f})
16844 Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
16846 @item @code{known-hosts} (default: @var{'()})
16847 List of hosts which allowed for SSH connection from @command{webssh}.
16849 @item @code{log-file} (default: @file{"/var/log/webssh.log"})
16850 Name of the file where @command{webssh} writes its log file.
16852 @item @code{log-level} (default: @var{#f})
16858 @defvr {Scheme Variable} %facebook-host-aliases
16859 This variable contains a string for use in @file{/etc/hosts}
16860 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
16861 line contains a entry that maps a known server name of the Facebook
16862 on-line service---e.g., @code{www.facebook.com}---to the local
16863 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
16865 This variable is typically used in the @code{hosts-file} field of an
16866 @code{operating-system} declaration (@pxref{operating-system Reference,
16867 @file{/etc/hosts}}):
16870 (use-modules (gnu) (guix))
16873 (host-name "mymachine")
16876 ;; Create a /etc/hosts file with aliases for "localhost"
16877 ;; and "mymachine", as well as for Facebook servers.
16878 (plain-file "hosts"
16879 (string-append (local-host-aliases host-name)
16880 %facebook-host-aliases))))
16883 This mechanism can prevent programs running locally, such as Web
16884 browsers, from accessing Facebook.
16887 The @code{(gnu services avahi)} provides the following definition.
16889 @defvr {Scheme Variable} avahi-service-type
16890 This is the service that runs @command{avahi-daemon}, a system-wide
16891 mDNS/DNS-SD responder that allows for service discovery and
16892 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
16893 Its value must be an @code{avahi-configuration} record---see below.
16895 This service extends the name service cache daemon (nscd) so that it can
16896 resolve @code{.local} host names using
16897 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
16898 Service Switch}, for information on host name resolution.
16900 Additionally, add the @var{avahi} package to the system profile so that
16901 commands such as @command{avahi-browse} are directly usable.
16904 @deftp {Data Type} avahi-configuration
16905 Data type representation the configuration for Avahi.
16909 @item @code{host-name} (default: @code{#f})
16910 If different from @code{#f}, use that as the host name to
16911 publish for this machine; otherwise, use the machine's actual host name.
16913 @item @code{publish?} (default: @code{#t})
16914 When true, allow host names and services to be published (broadcast) over the
16917 @item @code{publish-workstation?} (default: @code{#t})
16918 When true, @command{avahi-daemon} publishes the machine's host name and IP
16919 address via mDNS on the local network. To view the host names published on
16920 your local network, you can run:
16923 avahi-browse _workstation._tcp
16926 @item @code{wide-area?} (default: @code{#f})
16927 When true, DNS-SD over unicast DNS is enabled.
16929 @item @code{ipv4?} (default: @code{#t})
16930 @itemx @code{ipv6?} (default: @code{#t})
16931 These fields determine whether to use IPv4/IPv6 sockets.
16933 @item @code{domains-to-browse} (default: @code{'()})
16934 This is a list of domains to browse.
16938 @deffn {Scheme Variable} openvswitch-service-type
16939 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
16940 service, whose value should be an @code{openvswitch-configuration}
16944 @deftp {Data Type} openvswitch-configuration
16945 Data type representing the configuration of Open vSwitch, a multilayer
16946 virtual switch which is designed to enable massive network automation
16947 through programmatic extension.
16950 @item @code{package} (default: @var{openvswitch})
16951 Package object of the Open vSwitch.
16956 @defvr {Scheme Variable} pagekite-service-type
16957 This is the service type for the @uref{https://pagekite.net, PageKite} service,
16958 a tunneling solution for making localhost servers publicly visible, even from
16959 behind restrictive firewalls or NAT without forwarded ports. The value for
16960 this service type is a @code{pagekite-configuration} record.
16962 Here's an example exposing the local HTTP and SSH daemons:
16965 (service pagekite-service-type
16966 (pagekite-configuration
16967 (kites '("http:@@kitename:localhost:80:@@kitesecret"
16968 "raw/22:@@kitename:localhost:22:@@kitesecret"))
16969 (extra-file "/etc/pagekite.rc")))
16973 @deftp {Data Type} pagekite-configuration
16974 Data type representing the configuration of PageKite.
16977 @item @code{package} (default: @var{pagekite})
16978 Package object of PageKite.
16980 @item @code{kitename} (default: @code{#f})
16981 PageKite name for authenticating to the frontend server.
16983 @item @code{kitesecret} (default: @code{#f})
16984 Shared secret for authenticating to the frontend server. You should probably
16985 put this inside @code{extra-file} instead.
16987 @item @code{frontend} (default: @code{#f})
16988 Connect to the named PageKite frontend server instead of the
16989 @uref{https://pagekite.net,,pagekite.net} service.
16991 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
16992 List of service kites to use. Exposes HTTP on port 80 by default. The format
16993 is @code{proto:kitename:host:port:secret}.
16995 @item @code{extra-file} (default: @code{#f})
16996 Extra configuration file to read, which you are expected to create manually.
16997 Use this to add additional options and manage shared secrets out-of-band.
17002 @defvr {Scheme Variable} yggdrasil-service-type
17003 The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
17004 Yggdrasil network}, an early-stage implementation of a fully end-to-end
17005 encrypted IPv6 network.
17008 Yggdrasil provides name-independent routing with cryptographically generated
17009 addresses. Static addressing means you can keep the same address as long as
17010 you want, even if you move to a new location, or generate a new address (by
17011 generating new keys) whenever you want.
17012 @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
17015 Pass it a value of @code{yggdrasil-configuration} to connect it to public
17016 peers and/or local peers.
17018 Here is an example using public peers and a static address. The static
17019 signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
17020 (the default value for @code{config-file}).
17023 ;; part of the operating-system declaration
17024 (service yggdrasil-service-type
17025 (yggdrasil-configuration
17026 (autoconf? #f) ;; use only the public peers
17029 ;; https://github.com/yggdrasil-network/public-peers
17030 '((peers . #("tcp://1.2.3.4:1337"))))
17031 ;; /etc/yggdrasil-private.conf is the default value for config-file
17035 # sample content for /etc/yggdrasil-private.conf
17037 # Your public encryption key. Your peers may ask you for this to put
17038 # into their AllowedEncryptionPublicKeys configuration.
17039 EncryptionPublicKey: 378dc5...
17041 # Your private encryption key. DO NOT share this with anyone!
17042 EncryptionPrivateKey: 0777...
17044 # Your public signing key. You should not ordinarily need to share
17045 # this with anyone.
17046 SigningPublicKey: e1664...
17048 # Your private signing key. DO NOT share this with anyone!
17049 SigningPrivateKey: 0589d...
17054 @deftp {Data Type} yggdrasil-configuration
17055 Data type representing the configuration of Yggdrasil.
17058 @item @code{package} (default: @code{yggdrasil})
17059 Package object of Yggdrasil.
17061 @item @code{json-config} (default: @code{'()})
17062 Contents of @file{/etc/yggdrasil.conf}. Will be merged with
17063 @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
17064 the Guix store, which is readable to all users. @strong{Do not store your
17065 private keys in it}. See the output of @code{yggdrasil -genconf} for a
17066 quick overview of valid keys and their default values.
17068 @item @code{autoconf?} (default: @code{#f})
17069 Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
17070 and peer with IPv6 neighbors.
17072 @item @code{log-level} (default: @code{'info})
17073 How much detail to include in logs. Use @code{'debug} for more detail.
17075 @item @code{log-to} (default: @code{'stdout})
17076 Where to send logs. By default, the service logs standard output to
17077 @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
17078 sends output to the running syslog service.
17080 @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
17081 What HJSON file to load sensitive data from. This is where private keys
17082 should be stored, which are necessary to specify if you don't want a
17083 randomized address after each restart. Use @code{#f} to disable. Options
17084 defined in this file take precedence over @code{json-config}. Use the output
17085 of @code{yggdrasil -genconf} as a starting point. To configure a static
17086 address, delete everything except these options:
17089 @item @code{EncryptionPublicKey}
17090 @item @code{EncryptionPrivateKey}
17091 @item @code{SigningPublicKey}
17092 @item @code{SigningPrivateKey}
17097 @node Unattended Upgrades
17098 @subsection Unattended Upgrades
17100 @cindex unattended upgrades
17101 @cindex upgrades, unattended
17102 Guix provides a service to perform @emph{unattended upgrades}:
17103 periodically, the system automatically reconfigures itself from the
17104 latest Guix. Guix System has several properties that make unattended
17109 upgrades are transactional (either the upgrade succeeds or it fails, but
17110 you cannot end up with an ``in-between'' system state);
17112 the upgrade log is kept---you can view it with @command{guix system
17113 list-generations}---and you can roll back to any previous generation,
17114 should the upgraded system fail to behave as intended;
17116 channel code is authenticated so you know you can only run genuine code
17117 (@pxref{Channels});
17119 @command{guix system reconfigure} prevents downgrades, which makes it
17120 immune to @dfn{downgrade attacks}.
17123 To set up unattended upgrades, add an instance of
17124 @code{unattended-upgrade-service-type} like the one below to the list of
17125 your operating system services:
17128 (service unattended-upgrade-service-type)
17131 The defaults above set up weekly upgrades: every Sunday at midnight.
17132 You do not need to provide the operating system configuration file: it
17133 uses @file{/run/current-system/configuration.scm}, which ensures it
17134 always uses your latest configuration---@pxref{provenance-service-type},
17135 for more information about this file.
17137 There are several things that can be configured, in particular the
17138 periodicity and services (daemons) to be restarted upon completion.
17139 When the upgrade is successful, the service takes care of deleting
17140 system generations older that some threshold, as per @command{guix
17141 system delete-generations}. See the reference below for details.
17143 To ensure that upgrades are actually happening, you can run
17144 @command{guix system describe}. To investigate upgrade failures, visit
17145 the unattended upgrade log file (see below).
17147 @defvr {Scheme Variable} unattended-upgrade-service-type
17148 This is the service type for unattended upgrades. It sets up an mcron
17149 job (@pxref{Scheduled Job Execution}) that runs @command{guix system
17150 reconfigure} from the latest version of the specified channels.
17152 Its value must be a @code{unattended-upgrade-configuration} record (see
17156 @deftp {Data Type} unattended-upgrade-configuration
17157 This data type represents the configuration of the unattended upgrade
17158 service. The following fields are available:
17161 @item @code{schedule} (default: @code{"30 01 * * 0"})
17162 This is the schedule of upgrades, expressed as a gexp containing an
17163 mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
17164 mcron, GNU@tie{}mcron}).
17166 @item @code{channels} (default: @code{#~%default-channels})
17167 This gexp specifies the channels to use for the upgrade
17168 (@pxref{Channels}). By default, the tip of the official @code{guix}
17171 @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
17172 This field specifies the operating system configuration file to use.
17173 The default is to reuse the config file of the current configuration.
17175 There are cases, though, where referring to
17176 @file{/run/current-system/configuration.scm} is not enough, for instance
17177 because that file refers to extra files (SSH public keys, extra
17178 configuration files, etc.) @i{via} @code{local-file} and similar
17179 constructs. For those cases, we recommend something along these lines:
17182 (unattended-upgrade-configuration
17183 (operating-system-file
17184 (file-append (local-file "." "config-dir" #:recursive? #t)
17188 The effect here is to import all of the current directory into the
17189 store, and to refer to @file{config.scm} within that directory.
17190 Therefore, uses of @code{local-file} within @file{config.scm} will work
17191 as expected. @xref{G-Expressions}, for information about
17192 @code{local-file} and @code{file-append}.
17194 @item @code{services-to-restart} (default: @code{'(mcron)})
17195 This field specifies the Shepherd services to restart when the upgrade
17198 Those services are restarted right away upon completion, as with
17199 @command{herd restart}, which ensures that the latest version is
17200 running---remember that by default @command{guix system reconfigure}
17201 only restarts services that are not currently running, which is
17202 conservative: it minimizes disruption but leaves outdated services
17205 Use @command{herd status} to find out candidates for restarting.
17206 @xref{Services}, for general information about services. Common
17207 services to restart would include @code{ntpd} and @code{ssh-daemon}.
17209 By default, the @code{mcron} service is restarted. This ensures that
17210 the latest version of the unattended upgrade job will be used next time.
17212 @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
17213 This is the expiration time in seconds for system generations. System
17214 generations older that this amount of time are deleted with
17215 @command{guix system delete-generations} when an upgrade completes.
17218 The unattended upgrade service does not run the garbage collector. You
17219 will probably want to set up your own mcron job to run @command{guix gc}
17223 @item @code{maximum-duration} (default: @code{3600})
17224 Maximum duration in seconds for the upgrade; past that time, the upgrade
17227 This is primarily useful to ensure the upgrade does not end up
17228 rebuilding or re-downloading ``the world''.
17230 @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
17231 File where unattended upgrades are logged.
17236 @subsection X Window
17239 @cindex X Window System
17240 @cindex login manager
17241 Support for the X Window graphical display system---specifically
17242 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
17243 there is no @code{xorg-service} procedure. Instead, the X server is
17244 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
17247 @cindex GNOME, login manager
17248 GDM of course allows users to log in into window managers and desktop
17249 environments other than GNOME; for those using GNOME, GDM is required for
17250 features such as automatic screen locking.
17252 @cindex window manager
17253 To use X11, you must install at least one @dfn{window manager}---for
17254 example the @code{windowmaker} or @code{openbox} packages---preferably
17255 by adding it to the @code{packages} field of your operating system
17256 definition (@pxref{operating-system Reference, system-wide packages}).
17258 @defvr {Scheme Variable} gdm-service-type
17259 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
17260 Desktop Manager} (GDM), a program that manages graphical display servers and
17261 handles graphical user logins. Its value must be a @code{gdm-configuration}
17264 @cindex session types (X11)
17265 @cindex X11 session types
17266 GDM looks for @dfn{session types} described by the @file{.desktop} files in
17267 @file{/run/current-system/profile/share/xsessions} and allows users to choose
17268 a session from the log-in screen. Packages such as @code{gnome}, @code{xfce},
17269 and @code{i3} provide @file{.desktop} files; adding them to the system-wide
17270 set of packages automatically makes them available at the log-in screen.
17272 In addition, @file{~/.xsession} files are honored. When available,
17273 @file{~/.xsession} must be an executable that starts a window manager
17274 and/or other X clients.
17277 @deftp {Data Type} gdm-configuration
17279 @item @code{auto-login?} (default: @code{#f})
17280 @itemx @code{default-user} (default: @code{#f})
17281 When @code{auto-login?} is false, GDM presents a log-in screen.
17283 When @code{auto-login?} is true, GDM logs in directly as
17284 @code{default-user}.
17286 @item @code{debug?} (default: @code{#f})
17287 When true, GDM writes debug messages to its log.
17289 @item @code{gnome-shell-assets} (default: ...)
17290 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
17292 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
17293 Configuration of the Xorg graphical server.
17295 @item @code{xsession} (default: @code{(xinitrc)})
17296 Script to run before starting a X session.
17298 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
17299 File name of the @code{dbus-daemon} executable.
17301 @item @code{gdm} (default: @code{gdm})
17302 The GDM package to use.
17306 @defvr {Scheme Variable} slim-service-type
17307 This is the type for the SLiM graphical login manager for X11.
17309 Like GDM, SLiM looks for session types described by @file{.desktop} files and
17310 allows users to choose a session from the log-in screen using @kbd{F1}. It
17311 also honors @file{~/.xsession} files.
17313 Unlike GDM, SLiM does not spawn the user session on a different VT after
17314 logging in, which means that you can only start one graphical session. If you
17315 want to be able to run multiple graphical sessions at the same time you have
17316 to add multiple SLiM services to your system services. The following example
17317 shows how to replace the default GDM service with two SLiM services on tty7
17321 (use-modules (gnu services)
17322 (gnu services desktop)
17323 (gnu services xorg)
17324 (srfi srfi-1)) ;for 'remove'
17328 (services (cons* (service slim-service-type (slim-configuration
17331 (service slim-service-type (slim-configuration
17334 (remove (lambda (service)
17335 (eq? (service-kind service) gdm-service-type))
17336 %desktop-services))))
17341 @deftp {Data Type} slim-configuration
17342 Data type representing the configuration of @code{slim-service-type}.
17345 @item @code{allow-empty-passwords?} (default: @code{#t})
17346 Whether to allow logins with empty passwords.
17348 @item @code{auto-login?} (default: @code{#f})
17349 @itemx @code{default-user} (default: @code{""})
17350 When @code{auto-login?} is false, SLiM presents a log-in screen.
17352 When @code{auto-login?} is true, SLiM logs in directly as
17353 @code{default-user}.
17355 @item @code{theme} (default: @code{%default-slim-theme})
17356 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
17357 The graphical theme to use and its name.
17359 @item @code{auto-login-session} (default: @code{#f})
17360 If true, this must be the name of the executable to start as the default
17361 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
17363 If false, a session described by one of the available @file{.desktop}
17364 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
17368 You must install at least one window manager in the system profile or in
17369 your user profile. Failing to do that, if @code{auto-login-session} is
17370 false, you will be unable to log in.
17373 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
17374 Configuration of the Xorg graphical server.
17376 @item @code{display} (default @code{":0"})
17377 The display on which to start the Xorg graphical server.
17379 @item @code{vt} (default @code{"vt7"})
17380 The VT on which to start the Xorg graphical server.
17382 @item @code{xauth} (default: @code{xauth})
17383 The XAuth package to use.
17385 @item @code{shepherd} (default: @code{shepherd})
17386 The Shepherd package used when invoking @command{halt} and
17389 @item @code{sessreg} (default: @code{sessreg})
17390 The sessreg package used in order to register the session.
17392 @item @code{slim} (default: @code{slim})
17393 The SLiM package to use.
17397 @defvr {Scheme Variable} %default-theme
17398 @defvrx {Scheme Variable} %default-theme-name
17399 The default SLiM theme and its name.
17403 @deftp {Data Type} sddm-configuration
17404 This is the data type representing the SDDM service configuration.
17407 @item @code{display-server} (default: "x11")
17408 Select display server to use for the greeter. Valid values are
17409 @samp{"x11"} or @samp{"wayland"}.
17411 @item @code{numlock} (default: "on")
17412 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
17414 @item @code{halt-command} (default @code{#~(string-apppend #$shepherd "/sbin/halt")})
17415 Command to run when halting.
17417 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
17418 Command to run when rebooting.
17420 @item @code{theme} (default "maldives")
17421 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
17422 @samp{"maldives"} or @samp{"maya"}.
17424 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
17425 Directory to look for themes.
17427 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
17428 Directory to look for faces.
17430 @item @code{default-path} (default "/run/current-system/profile/bin")
17431 Default PATH to use.
17433 @item @code{minimum-uid} (default: 1000)
17434 Minimum UID displayed in SDDM and allowed for log-in.
17436 @item @code{maximum-uid} (default: 2000)
17437 Maximum UID to display in SDDM.
17439 @item @code{remember-last-user?} (default #t)
17440 Remember last user.
17442 @item @code{remember-last-session?} (default #t)
17443 Remember last session.
17445 @item @code{hide-users} (default "")
17446 Usernames to hide from SDDM greeter.
17448 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
17449 Users with shells listed will be hidden from the SDDM greeter.
17451 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
17452 Script to run before starting a wayland session.
17454 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
17455 Directory to look for desktop files starting wayland sessions.
17457 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
17458 Configuration of the Xorg graphical server.
17460 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
17463 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
17466 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
17467 Script to run after starting xorg-server.
17469 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
17470 Script to run before stopping xorg-server.
17472 @item @code{xsession-command} (default: @code{xinitrc})
17473 Script to run before starting a X session.
17475 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
17476 Directory to look for desktop files starting X sessions.
17478 @item @code{minimum-vt} (default: 7)
17481 @item @code{auto-login-user} (default "")
17482 User to use for auto-login.
17484 @item @code{auto-login-session} (default "")
17485 Desktop file to use for auto-login.
17487 @item @code{relogin?} (default #f)
17488 Relogin after logout.
17493 @cindex login manager
17495 @defvr {Scheme Variable} sddm-service-type
17496 This is the type of the service to run the
17497 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
17498 must be a @code{sddm-configuration} record (see below).
17500 Here's an example use:
17503 (service sddm-service-type
17504 (sddm-configuration
17505 (auto-login-user "alice")
17506 (auto-login-session "xfce.desktop")))
17510 @deftp {Data Type} sddm-configuration
17511 This data type represents the configuration of the SDDM login manager.
17512 The available fields are:
17515 @item @code{sddm} (default: @code{sddm})
17516 The SDDM package to use.
17518 @item @code{display-server} (default: @code{"x11"})
17519 This must be either @code{"x11"} or @code{"wayland"}.
17521 @c FIXME: Add more fields.
17523 @item @code{auto-login-user} (default: @code{""})
17524 If non-empty, this is the user account under which to log in
17527 @item @code{auto-login-session} (default: @code{""})
17528 If non-empty, this is the @file{.desktop} file name to use as the
17529 auto-login session.
17533 @cindex Xorg, configuration
17534 @deftp {Data Type} xorg-configuration
17535 This data type represents the configuration of the Xorg graphical display
17536 server. Note that there is no Xorg service; instead, the X server is started
17537 by a ``display manager'' such as GDM, SDDM, and SLiM. Thus, the configuration
17538 of these display managers aggregates an @code{xorg-configuration} record.
17541 @item @code{modules} (default: @code{%default-xorg-modules})
17542 This is a list of @dfn{module packages} loaded by the Xorg
17543 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
17545 @item @code{fonts} (default: @code{%default-xorg-fonts})
17546 This is a list of font directories to add to the server's @dfn{font path}.
17548 @item @code{drivers} (default: @code{'()})
17549 This must be either the empty list, in which case Xorg chooses a graphics
17550 driver automatically, or a list of driver names that will be tried in this
17551 order---e.g., @code{("modesetting" "vesa")}.
17553 @item @code{resolutions} (default: @code{'()})
17554 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
17555 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
17558 @cindex keyboard layout, for Xorg
17559 @cindex keymap, for Xorg
17560 @item @code{keyboard-layout} (default: @code{#f})
17561 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
17562 English (``qwerty'') for a 105-key PC keyboard.
17564 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
17565 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
17566 information on how to specify the keyboard layout.
17568 @item @code{extra-config} (default: @code{'()})
17569 This is a list of strings or objects appended to the configuration file. It
17570 is used to pass extra text to be added verbatim to the configuration file.
17572 @item @code{server} (default: @code{xorg-server})
17573 This is the package providing the Xorg server.
17575 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
17576 This is the list of command-line arguments to pass to the X server. The
17577 default is @code{-nolisten tcp}.
17581 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
17582 [@var{login-manager-service-type}]
17583 Tell the log-in manager (of type @var{login-manager-service-type}) to use
17584 @var{config}, an @code{<xorg-configuration>} record.
17586 Since the Xorg configuration is embedded in the log-in manager's
17587 configuration---e.g., @code{gdm-configuration}---this procedure provides a
17588 shorthand to set the Xorg configuration.
17591 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
17592 Return a @code{startx} script in which the modules, fonts, etc. specified
17593 in @var{config}, are available. The result should be used in place of
17596 Usually the X server is started by a login manager.
17600 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
17601 Add @var{package}, a package for a screen locker or screen saver whose
17602 command is @var{program}, to the set of setuid programs and add a PAM entry
17603 for it. For example:
17606 (screen-locker-service xlockmore "xlock")
17609 makes the good ol' XlockMore usable.
17613 @node Printing Services
17614 @subsection Printing Services
17616 @cindex printer support with CUPS
17617 The @code{(gnu services cups)} module provides a Guix service definition
17618 for the CUPS printing service. To add printer support to a Guix
17619 system, add a @code{cups-service} to the operating system definition:
17621 @deffn {Scheme Variable} cups-service-type
17622 The service type for the CUPS print server. Its value should be a valid
17623 CUPS configuration (see below). To use the default settings, simply
17626 (service cups-service-type)
17630 The CUPS configuration controls the basic things about your CUPS
17631 installation: what interfaces it listens on, what to do if a print job
17632 fails, how much logging to do, and so on. To actually add a printer,
17633 you have to visit the @url{http://localhost:631} URL, or use a tool such
17634 as GNOME's printer configuration services. By default, configuring a
17635 CUPS service will generate a self-signed certificate if needed, for
17636 secure connections to the print server.
17638 Suppose you want to enable the Web interface of CUPS and also add
17639 support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
17640 package and for HP printers @i{via} the @code{hplip-minimal} package.
17641 You can do that directly, like this (you need to use the
17642 @code{(gnu packages cups)} module):
17645 (service cups-service-type
17646 (cups-configuration
17647 (web-interface? #t)
17649 (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
17652 Note: If you wish to use the Qt5 based GUI which comes with the hplip
17653 package then it is suggested that you install the @code{hplip} package,
17654 either in your OS configuration file or as your user.
17656 The available configuration parameters follow. Each parameter
17657 definition is preceded by its type; for example, @samp{string-list foo}
17658 indicates that the @code{foo} parameter should be specified as a list of
17659 strings. There is also a way to specify the configuration as a string,
17660 if you have an old @code{cupsd.conf} file that you want to port over
17661 from some other system; see the end for more details.
17663 @c The following documentation was initially generated by
17664 @c (generate-documentation) in (gnu services cups). Manually maintained
17665 @c documentation is better, so we shouldn't hesitate to edit below as
17666 @c needed. However if the change you want to make to this documentation
17667 @c can be done in an automated way, it's probably easier to change
17668 @c (generate-documentation) than to make it below and have to deal with
17669 @c the churn as CUPS updates.
17672 Available @code{cups-configuration} fields are:
17674 @deftypevr {@code{cups-configuration} parameter} package cups
17678 @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list epson-inkjet-printer-escpr hplip-minimal foomatic-filters splix)})
17679 Drivers and other extensions to the CUPS package.
17682 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
17683 Configuration of where to write logs, what directories to use for print
17684 spools, and related privileged configuration parameters.
17686 Available @code{files-configuration} fields are:
17688 @deftypevr {@code{files-configuration} parameter} log-location access-log
17689 Defines the access log filename. Specifying a blank filename disables
17690 access log generation. The value @code{stderr} causes log entries to be
17691 sent to the standard error file when the scheduler is running in the
17692 foreground, or to the system log daemon when run in the background. The
17693 value @code{syslog} causes log entries to be sent to the system log
17694 daemon. The server name may be included in filenames using the string
17695 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
17697 Defaults to @samp{"/var/log/cups/access_log"}.
17700 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
17701 Where CUPS should cache data.
17703 Defaults to @samp{"/var/cache/cups"}.
17706 @deftypevr {@code{files-configuration} parameter} string config-file-perm
17707 Specifies the permissions for all configuration files that the scheduler
17710 Note that the permissions for the printers.conf file are currently
17711 masked to only allow access from the scheduler user (typically root).
17712 This is done because printer device URIs sometimes contain sensitive
17713 authentication information that should not be generally known on the
17714 system. There is no way to disable this security feature.
17716 Defaults to @samp{"0640"}.
17719 @deftypevr {@code{files-configuration} parameter} log-location error-log
17720 Defines the error log filename. Specifying a blank filename disables
17721 error log generation. The value @code{stderr} causes log entries to be
17722 sent to the standard error file when the scheduler is running in the
17723 foreground, or to the system log daemon when run in the background. The
17724 value @code{syslog} causes log entries to be sent to the system log
17725 daemon. The server name may be included in filenames using the string
17726 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
17728 Defaults to @samp{"/var/log/cups/error_log"}.
17731 @deftypevr {@code{files-configuration} parameter} string fatal-errors
17732 Specifies which errors are fatal, causing the scheduler to exit. The
17737 No errors are fatal.
17740 All of the errors below are fatal.
17743 Browsing initialization errors are fatal, for example failed connections
17744 to the DNS-SD daemon.
17747 Configuration file syntax errors are fatal.
17750 Listen or Port errors are fatal, except for IPv6 failures on the
17751 loopback or @code{any} addresses.
17754 Log file creation or write errors are fatal.
17757 Bad startup file permissions are fatal, for example shared TLS
17758 certificate and key files with world-read permissions.
17761 Defaults to @samp{"all -browse"}.
17764 @deftypevr {@code{files-configuration} parameter} boolean file-device?
17765 Specifies whether the file pseudo-device can be used for new printer
17766 queues. The URI @uref{file:///dev/null} is always allowed.
17768 Defaults to @samp{#f}.
17771 @deftypevr {@code{files-configuration} parameter} string group
17772 Specifies the group name or ID that will be used when executing external
17775 Defaults to @samp{"lp"}.
17778 @deftypevr {@code{files-configuration} parameter} string log-file-perm
17779 Specifies the permissions for all log files that the scheduler writes.
17781 Defaults to @samp{"0644"}.
17784 @deftypevr {@code{files-configuration} parameter} log-location page-log
17785 Defines the page log filename. Specifying a blank filename disables
17786 page log generation. The value @code{stderr} causes log entries to be
17787 sent to the standard error file when the scheduler is running in the
17788 foreground, or to the system log daemon when run in the background. The
17789 value @code{syslog} causes log entries to be sent to the system log
17790 daemon. The server name may be included in filenames using the string
17791 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
17793 Defaults to @samp{"/var/log/cups/page_log"}.
17796 @deftypevr {@code{files-configuration} parameter} string remote-root
17797 Specifies the username that is associated with unauthenticated accesses
17798 by clients claiming to be the root user. The default is @code{remroot}.
17800 Defaults to @samp{"remroot"}.
17803 @deftypevr {@code{files-configuration} parameter} file-name request-root
17804 Specifies the directory that contains print jobs and other HTTP request
17807 Defaults to @samp{"/var/spool/cups"}.
17810 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
17811 Specifies the level of security sandboxing that is applied to print
17812 filters, backends, and other child processes of the scheduler; either
17813 @code{relaxed} or @code{strict}. This directive is currently only
17814 used/supported on macOS.
17816 Defaults to @samp{strict}.
17819 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
17820 Specifies the location of TLS certificates and private keys. CUPS will
17821 look for public and private keys in this directory: @file{.crt} files
17822 for PEM-encoded certificates and corresponding @file{.key} files for
17823 PEM-encoded private keys.
17825 Defaults to @samp{"/etc/cups/ssl"}.
17828 @deftypevr {@code{files-configuration} parameter} file-name server-root
17829 Specifies the directory containing the server configuration files.
17831 Defaults to @samp{"/etc/cups"}.
17834 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
17835 Specifies whether the scheduler calls fsync(2) after writing
17836 configuration or state files.
17838 Defaults to @samp{#f}.
17841 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
17842 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
17845 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
17846 Specifies the directory where temporary files are stored.
17848 Defaults to @samp{"/var/spool/cups/tmp"}.
17851 @deftypevr {@code{files-configuration} parameter} string user
17852 Specifies the user name or ID that is used when running external
17855 Defaults to @samp{"lp"}.
17858 @deftypevr {@code{files-configuration} parameter} string set-env
17859 Set the specified environment variable to be passed to child processes.
17861 Defaults to @samp{"variable value"}.
17865 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
17866 Specifies the logging level for the AccessLog file. The @code{config}
17867 level logs when printers and classes are added, deleted, or modified and
17868 when configuration files are accessed or updated. The @code{actions}
17869 level logs when print jobs are submitted, held, released, modified, or
17870 canceled, and any of the conditions for @code{config}. The @code{all}
17871 level logs all requests.
17873 Defaults to @samp{actions}.
17876 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
17877 Specifies whether to purge job history data automatically when it is no
17878 longer required for quotas.
17880 Defaults to @samp{#f}.
17883 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
17884 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
17885 For example, @samp{"_cups" "_print"} will tell network clients that both
17886 CUPS sharing and IPP Everywhere are supported.
17888 Defaults to @samp{"_cups"}.
17891 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
17892 Specifies which protocols to use for local printer sharing.
17894 Defaults to @samp{dnssd}.
17897 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
17898 Specifies whether the CUPS web interface is advertised.
17900 Defaults to @samp{#f}.
17903 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
17904 Specifies whether shared printers are advertised.
17906 Defaults to @samp{#f}.
17909 @deftypevr {@code{cups-configuration} parameter} string classification
17910 Specifies the security classification of the server. Any valid banner
17911 name can be used, including @samp{"classified"}, @samp{"confidential"},
17912 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
17913 banner can be omitted to disable secure printing functions.
17915 Defaults to @samp{""}.
17918 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
17919 Specifies whether users may override the classification (cover page) of
17920 individual print jobs using the @code{job-sheets} option.
17922 Defaults to @samp{#f}.
17925 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
17926 Specifies the default type of authentication to use.
17928 Defaults to @samp{Basic}.
17931 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
17932 Specifies whether encryption will be used for authenticated requests.
17934 Defaults to @samp{Required}.
17937 @deftypevr {@code{cups-configuration} parameter} string default-language
17938 Specifies the default language to use for text and web content.
17940 Defaults to @samp{"en"}.
17943 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
17944 Specifies the default paper size for new print queues. @samp{"Auto"}
17945 uses a locale-specific default, while @samp{"None"} specifies there is
17946 no default paper size. Specific size names are typically
17947 @samp{"Letter"} or @samp{"A4"}.
17949 Defaults to @samp{"Auto"}.
17952 @deftypevr {@code{cups-configuration} parameter} string default-policy
17953 Specifies the default access policy to use.
17955 Defaults to @samp{"default"}.
17958 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
17959 Specifies whether local printers are shared by default.
17961 Defaults to @samp{#t}.
17964 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
17965 Specifies the delay for updating of configuration and state files, in
17966 seconds. A value of 0 causes the update to happen as soon as possible,
17967 typically within a few milliseconds.
17969 Defaults to @samp{30}.
17972 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
17973 Specifies what to do when an error occurs. Possible values are
17974 @code{abort-job}, which will discard the failed print job;
17975 @code{retry-job}, which will retry the job at a later time;
17976 @code{retry-current-job}, which retries the failed job immediately; and
17977 @code{stop-printer}, which stops the printer.
17979 Defaults to @samp{stop-printer}.
17982 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
17983 Specifies the maximum cost of filters that are run concurrently, which
17984 can be used to minimize disk, memory, and CPU resource problems. A
17985 limit of 0 disables filter limiting. An average print to a
17986 non-PostScript printer needs a filter limit of about 200. A PostScript
17987 printer needs about half that (100). Setting the limit below these
17988 thresholds will effectively limit the scheduler to printing a single job
17991 Defaults to @samp{0}.
17994 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
17995 Specifies the scheduling priority of filters that are run to print a
17996 job. The nice value ranges from 0, the highest priority, to 19, the
17999 Defaults to @samp{0}.
18002 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
18003 Specifies whether to do reverse lookups on connecting clients. The
18004 @code{double} setting causes @code{cupsd} to verify that the hostname
18005 resolved from the address matches one of the addresses returned for that
18006 hostname. Double lookups also prevent clients with unregistered
18007 addresses from connecting to your server. Only set this option to
18008 @code{#t} or @code{double} if absolutely required.
18010 Defaults to @samp{#f}.
18013 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
18014 Specifies the number of seconds to wait before killing the filters and
18015 backend associated with a canceled or held job.
18017 Defaults to @samp{30}.
18020 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
18021 Specifies the interval between retries of jobs in seconds. This is
18022 typically used for fax queues but can also be used with normal print
18023 queues whose error policy is @code{retry-job} or
18024 @code{retry-current-job}.
18026 Defaults to @samp{30}.
18029 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
18030 Specifies the number of retries that are done for jobs. This is
18031 typically used for fax queues but can also be used with normal print
18032 queues whose error policy is @code{retry-job} or
18033 @code{retry-current-job}.
18035 Defaults to @samp{5}.
18038 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
18039 Specifies whether to support HTTP keep-alive connections.
18041 Defaults to @samp{#t}.
18044 @deftypevr {@code{cups-configuration} parameter} non-negative-integer keep-alive-timeout
18045 Specifies how long an idle client connection remains open, in seconds.
18047 Defaults to @samp{30}.
18050 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
18051 Specifies the maximum size of print files, IPP requests, and HTML form
18052 data. A limit of 0 disables the limit check.
18054 Defaults to @samp{0}.
18057 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
18058 Listens on the specified interfaces for connections. Valid values are
18059 of the form @var{address}:@var{port}, where @var{address} is either an
18060 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
18061 indicate all addresses. Values can also be file names of local UNIX
18062 domain sockets. The Listen directive is similar to the Port directive
18063 but allows you to restrict access to specific interfaces or networks.
18066 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
18067 Specifies the number of pending connections that will be allowed. This
18068 normally only affects very busy servers that have reached the MaxClients
18069 limit, but can also be triggered by large numbers of simultaneous
18070 connections. When the limit is reached, the operating system will
18071 refuse additional connections until the scheduler can accept the pending
18074 Defaults to @samp{128}.
18077 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
18078 Specifies a set of additional access controls.
18080 Available @code{location-access-controls} fields are:
18082 @deftypevr {@code{location-access-controls} parameter} file-name path
18083 Specifies the URI path to which the access control applies.
18086 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
18087 Access controls for all access to this path, in the same format as the
18088 @code{access-controls} of @code{operation-access-control}.
18090 Defaults to @samp{()}.
18093 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
18094 Access controls for method-specific access to this path.
18096 Defaults to @samp{()}.
18098 Available @code{method-access-controls} fields are:
18100 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
18101 If @code{#t}, apply access controls to all methods except the listed
18102 methods. Otherwise apply to only the listed methods.
18104 Defaults to @samp{#f}.
18107 @deftypevr {@code{method-access-controls} parameter} method-list methods
18108 Methods to which this access control applies.
18110 Defaults to @samp{()}.
18113 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
18114 Access control directives, as a list of strings. Each string should be
18115 one directive, such as @samp{"Order allow,deny"}.
18117 Defaults to @samp{()}.
18122 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
18123 Specifies the number of debugging messages that are retained for logging
18124 if an error occurs in a print job. Debug messages are logged regardless
18125 of the LogLevel setting.
18127 Defaults to @samp{100}.
18130 @deftypevr {@code{cups-configuration} parameter} log-level log-level
18131 Specifies the level of logging for the ErrorLog file. The value
18132 @code{none} stops all logging while @code{debug2} logs everything.
18134 Defaults to @samp{info}.
18137 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
18138 Specifies the format of the date and time in the log files. The value
18139 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
18141 Defaults to @samp{standard}.
18144 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
18145 Specifies the maximum number of simultaneous clients that are allowed by
18148 Defaults to @samp{100}.
18151 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
18152 Specifies the maximum number of simultaneous clients that are allowed
18153 from a single address.
18155 Defaults to @samp{100}.
18158 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
18159 Specifies the maximum number of copies that a user can print of each
18162 Defaults to @samp{9999}.
18165 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
18166 Specifies the maximum time a job may remain in the @code{indefinite}
18167 hold state before it is canceled. A value of 0 disables cancellation of
18170 Defaults to @samp{0}.
18173 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
18174 Specifies the maximum number of simultaneous jobs that are allowed. Set
18175 to 0 to allow an unlimited number of jobs.
18177 Defaults to @samp{500}.
18180 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
18181 Specifies the maximum number of simultaneous jobs that are allowed per
18182 printer. A value of 0 allows up to MaxJobs jobs per printer.
18184 Defaults to @samp{0}.
18187 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
18188 Specifies the maximum number of simultaneous jobs that are allowed per
18189 user. A value of 0 allows up to MaxJobs jobs per user.
18191 Defaults to @samp{0}.
18194 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
18195 Specifies the maximum time a job may take to print before it is
18196 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
18198 Defaults to @samp{10800}.
18201 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
18202 Specifies the maximum size of the log files before they are rotated, in
18203 bytes. The value 0 disables log rotation.
18205 Defaults to @samp{1048576}.
18208 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
18209 Specifies the maximum amount of time to allow between files in a
18210 multiple file print job, in seconds.
18212 Defaults to @samp{300}.
18215 @deftypevr {@code{cups-configuration} parameter} string page-log-format
18216 Specifies the format of PageLog lines. Sequences beginning with percent
18217 (@samp{%}) characters are replaced with the corresponding information,
18218 while all other characters are copied literally. The following percent
18219 sequences are recognized:
18223 insert a single percent character
18226 insert the value of the specified IPP attribute
18229 insert the number of copies for the current page
18232 insert the current page number
18235 insert the current date and time in common log format
18241 insert the printer name
18244 insert the username
18247 A value of the empty string disables page logging. The string @code{%p
18248 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
18249 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
18252 Defaults to @samp{""}.
18255 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
18256 Passes the specified environment variable(s) to child processes; a list
18259 Defaults to @samp{()}.
18262 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
18263 Specifies named access control policies.
18265 Available @code{policy-configuration} fields are:
18267 @deftypevr {@code{policy-configuration} parameter} string name
18268 Name of the policy.
18271 @deftypevr {@code{policy-configuration} parameter} string job-private-access
18272 Specifies an access list for a job's private values. @code{@@ACL} maps
18273 to the printer's requesting-user-name-allowed or
18274 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
18275 owner. @code{@@SYSTEM} maps to the groups listed for the
18276 @code{system-group} field of the @code{files-config} configuration,
18277 which is reified into the @code{cups-files.conf(5)} file. Other
18278 possible elements of the access list include specific user names, and
18279 @code{@@@var{group}} to indicate members of a specific group. The
18280 access list may also be simply @code{all} or @code{default}.
18282 Defaults to @samp{"@@OWNER @@SYSTEM"}.
18285 @deftypevr {@code{policy-configuration} parameter} string job-private-values
18286 Specifies the list of job values to make private, or @code{all},
18287 @code{default}, or @code{none}.
18289 Defaults to @samp{"job-name job-originating-host-name
18290 job-originating-user-name phone"}.
18293 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
18294 Specifies an access list for a subscription's private values.
18295 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
18296 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
18297 owner. @code{@@SYSTEM} maps to the groups listed for the
18298 @code{system-group} field of the @code{files-config} configuration,
18299 which is reified into the @code{cups-files.conf(5)} file. Other
18300 possible elements of the access list include specific user names, and
18301 @code{@@@var{group}} to indicate members of a specific group. The
18302 access list may also be simply @code{all} or @code{default}.
18304 Defaults to @samp{"@@OWNER @@SYSTEM"}.
18307 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
18308 Specifies the list of job values to make private, or @code{all},
18309 @code{default}, or @code{none}.
18311 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
18312 notify-subscriber-user-name notify-user-data"}.
18315 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
18316 Access control by IPP operation.
18318 Defaults to @samp{()}.
18322 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
18323 Specifies whether job files (documents) are preserved after a job is
18324 printed. If a numeric value is specified, job files are preserved for
18325 the indicated number of seconds after printing. Otherwise a boolean
18326 value applies indefinitely.
18328 Defaults to @samp{86400}.
18331 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
18332 Specifies whether the job history is preserved after a job is printed.
18333 If a numeric value is specified, the job history is preserved for the
18334 indicated number of seconds after printing. If @code{#t}, the job
18335 history is preserved until the MaxJobs limit is reached.
18337 Defaults to @samp{#t}.
18340 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
18341 Specifies the amount of time to wait for job completion before
18342 restarting the scheduler.
18344 Defaults to @samp{30}.
18347 @deftypevr {@code{cups-configuration} parameter} string rip-cache
18348 Specifies the maximum amount of memory to use when converting documents
18349 into bitmaps for a printer.
18351 Defaults to @samp{"128m"}.
18354 @deftypevr {@code{cups-configuration} parameter} string server-admin
18355 Specifies the email address of the server administrator.
18357 Defaults to @samp{"root@@localhost.localdomain"}.
18360 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
18361 The ServerAlias directive is used for HTTP Host header validation when
18362 clients connect to the scheduler from external interfaces. Using the
18363 special name @code{*} can expose your system to known browser-based DNS
18364 rebinding attacks, even when accessing sites through a firewall. If the
18365 auto-discovery of alternate names does not work, we recommend listing
18366 each alternate name with a ServerAlias directive instead of using
18369 Defaults to @samp{*}.
18372 @deftypevr {@code{cups-configuration} parameter} string server-name
18373 Specifies the fully-qualified host name of the server.
18375 Defaults to @samp{"localhost"}.
18378 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
18379 Specifies what information is included in the Server header of HTTP
18380 responses. @code{None} disables the Server header. @code{ProductOnly}
18381 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
18382 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
18383 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
18384 the output of the @code{uname} command. @code{Full} reports @code{CUPS
18385 2.0.0 (@var{uname}) IPP/2.0}.
18387 Defaults to @samp{Minimal}.
18390 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
18391 Listens on the specified interfaces for encrypted connections. Valid
18392 values are of the form @var{address}:@var{port}, where @var{address} is
18393 either an IPv6 address enclosed in brackets, an IPv4 address, or
18394 @code{*} to indicate all addresses.
18396 Defaults to @samp{()}.
18399 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
18400 Sets encryption options. By default, CUPS only supports encryption
18401 using TLS v1.0 or higher using known secure cipher suites. Security is
18402 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
18403 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
18404 suites, which are required for some older clients. The @code{AllowSSL3} option
18405 enables SSL v3.0, which is required for some older clients that do not support
18406 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
18407 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
18408 protocol version to TLS v1.1.
18410 Defaults to @samp{()}.
18413 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
18414 Specifies whether the scheduler requires clients to strictly adhere to
18415 the IPP specifications.
18417 Defaults to @samp{#f}.
18420 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
18421 Specifies the HTTP request timeout, in seconds.
18423 Defaults to @samp{300}.
18427 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
18428 Specifies whether the web interface is enabled.
18430 Defaults to @samp{#f}.
18433 At this point you're probably thinking ``oh dear, Guix manual, I like
18434 you but you can stop already with the configuration options''. Indeed.
18435 However, one more point: it could be that you have an existing
18436 @code{cupsd.conf} that you want to use. In that case, you can pass an
18437 @code{opaque-cups-configuration} as the configuration of a
18438 @code{cups-service-type}.
18440 Available @code{opaque-cups-configuration} fields are:
18442 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
18446 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
18447 The contents of the @code{cupsd.conf}, as a string.
18450 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
18451 The contents of the @code{cups-files.conf} file, as a string.
18454 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
18455 strings of the same name, you could instantiate a CUPS service like
18459 (service cups-service-type
18460 (opaque-cups-configuration
18461 (cupsd.conf cupsd.conf)
18462 (cups-files.conf cups-files.conf)))
18466 @node Desktop Services
18467 @subsection Desktop Services
18469 The @code{(gnu services desktop)} module provides services that are
18470 usually useful in the context of a ``desktop'' setup---that is, on a
18471 machine running a graphical display server, possibly with graphical user
18472 interfaces, etc. It also defines services that provide specific desktop
18473 environments like GNOME, Xfce or MATE.
18475 To simplify things, the module defines a variable containing the set of
18476 services that users typically expect on a machine with a graphical
18477 environment and networking:
18479 @defvr {Scheme Variable} %desktop-services
18480 This is a list of services that builds upon @code{%base-services} and
18481 adds or adjusts services for a typical ``desktop'' setup.
18483 In particular, it adds a graphical login manager (@pxref{X Window,
18484 @code{gdm-service-type}}), screen lockers, a network management tool
18485 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
18486 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
18487 energy and color management services, the @code{elogind} login and seat
18488 manager, the Polkit privilege service, the GeoClue location service, the
18489 AccountsService daemon that allows authorized users change system passwords,
18490 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
18491 name service switch service configured to be able to use @code{nss-mdns}
18492 (@pxref{Name Service Switch, mDNS}).
18495 The @code{%desktop-services} variable can be used as the @code{services}
18496 field of an @code{operating-system} declaration (@pxref{operating-system
18497 Reference, @code{services}}).
18499 Additionally, the @code{gnome-desktop-service-type},
18500 @code{xfce-desktop-service}, @code{mate-desktop-service-type},
18501 @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
18502 procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
18503 ``add GNOME'' means that system-level services like the backlight adjustment
18504 helpers and the power management utilities are added to the system, extending
18505 @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
18506 elevated privileges on a limited number of special-purpose system interfaces.
18507 Additionally, adding a service made by @code{gnome-desktop-service-type} adds
18508 the GNOME metapackage to the system profile. Likewise, adding the Xfce
18509 service not only adds the @code{xfce} metapackage to the system profile, but
18510 it also gives the Thunar file manager the ability to open a ``root-mode'' file
18511 management window, if the user authenticates using the administrator's
18512 password via the standard polkit graphical interface. To ``add MATE'' means
18513 that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
18514 to operate with elevated privileges on a limited number of special-purpose
18515 system interfaces. Additionally, adding a service of type
18516 @code{mate-desktop-service-type} adds the MATE metapackage to the system
18517 profile. ``Adding Enlightenment'' means that @code{dbus} is extended
18518 appropriately, and several of Enlightenment's binaries are set as setuid,
18519 allowing Enlightenment's screen locker and other functionality to work as
18522 The desktop environments in Guix use the Xorg display server by
18523 default. If you'd like to use the newer display server protocol
18524 called Wayland, you need to use the @code{sddm-service} instead of
18525 GDM as the graphical login manager. You should then
18526 select the ``GNOME (Wayland)'' session in SDDM. Alternatively you can
18527 also try starting GNOME on Wayland manually from a TTY with the
18528 command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
18529 gnome-session``. Currently only GNOME has support for Wayland.
18531 @defvr {Scheme Variable} gnome-desktop-service-type
18532 This is the type of the service that adds the @uref{https://www.gnome.org,
18533 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
18534 object (see below).
18536 This service adds the @code{gnome} package to the system profile, and extends
18537 polkit with the actions from @code{gnome-settings-daemon}.
18540 @deftp {Data Type} gnome-desktop-configuration
18541 Configuration record for the GNOME desktop environment.
18544 @item @code{gnome} (default: @code{gnome})
18545 The GNOME package to use.
18549 @defvr {Scheme Variable} xfce-desktop-service-type
18550 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
18551 desktop environment. Its value is an @code{xfce-desktop-configuration} object
18554 This service adds the @code{xfce} package to the system profile, and
18555 extends polkit with the ability for @code{thunar} to manipulate the file
18556 system as root from within a user session, after the user has authenticated
18557 with the administrator's password.
18560 @deftp {Data Type} xfce-desktop-configuration
18561 Configuration record for the Xfce desktop environment.
18564 @item @code{xfce} (default: @code{xfce})
18565 The Xfce package to use.
18569 @deffn {Scheme Variable} mate-desktop-service-type
18570 This is the type of the service that runs the @uref{https://mate-desktop.org/,
18571 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
18572 object (see below).
18574 This service adds the @code{mate} package to the system
18575 profile, and extends polkit with the actions from
18576 @code{mate-settings-daemon}.
18579 @deftp {Data Type} mate-desktop-configuration
18580 Configuration record for the MATE desktop environment.
18583 @item @code{mate} (default: @code{mate})
18584 The MATE package to use.
18588 @deffn {Scheme Variable} lxqt-desktop-service-type
18589 This is the type of the service that runs the @uref{https://lxqt.github.io,
18590 LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
18591 object (see below).
18593 This service adds the @code{lxqt} package to the system
18597 @deftp {Data Type} lxqt-desktop-configuration
18598 Configuration record for the LXQt desktop environment.
18601 @item @code{lxqt} (default: @code{lxqt})
18602 The LXQT package to use.
18606 @deffn {Scheme Variable} enlightenment-desktop-service-type
18607 Return a service that adds the @code{enlightenment} package to the system
18608 profile, and extends dbus with actions from @code{efl}.
18611 @deftp {Data Type} enlightenment-desktop-service-configuration
18613 @item @code{enlightenment} (default: @code{enlightenment})
18614 The enlightenment package to use.
18618 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
18619 the default @code{%desktop-services} variable doesn't include any of
18620 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
18621 @code{%desktop-services} in the @code{services} field of your
18622 @code{operating-system}:
18625 (use-modules (gnu))
18626 (use-service-modules desktop)
18629 ;; cons* adds items to the list given as its last argument.
18630 (services (cons* (service gnome-desktop-service-type)
18631 (service xfce-desktop-service)
18632 %desktop-services))
18636 These desktop environments will then be available as options in the
18637 graphical login window.
18639 The actual service definitions included in @code{%desktop-services} and
18640 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
18641 are described below.
18643 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()]
18644 Return a service that runs the ``system bus'', using @var{dbus}, with
18645 support for @var{services}.
18647 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
18648 facility. Its system bus is used to allow system services to communicate
18649 and to be notified of system-wide events.
18651 @var{services} must be a list of packages that provide an
18652 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
18653 and policy files. For example, to allow avahi-daemon to use the system bus,
18654 @var{services} must be equal to @code{(list avahi)}.
18657 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
18658 Return a service that runs the @code{elogind} login and
18659 seat management daemon. @uref{https://github.com/elogind/elogind,
18660 Elogind} exposes a D-Bus interface that can be used to know which users
18661 are logged in, know what kind of sessions they have open, suspend the
18662 system, inhibit system suspend, reboot the system, and other tasks.
18664 Elogind handles most system-level power events for a computer, for
18665 example suspending the system when a lid is closed, or shutting it down
18666 when the power button is pressed.
18668 The @var{config} keyword argument specifies the configuration for
18669 elogind, and should be the result of an @code{(elogind-configuration
18670 (@var{parameter} @var{value})...)} invocation. Available parameters and
18671 their default values are:
18674 @item kill-user-processes?
18676 @item kill-only-users
18678 @item kill-exclude-users
18680 @item inhibit-delay-max-seconds
18682 @item handle-power-key
18684 @item handle-suspend-key
18686 @item handle-hibernate-key
18688 @item handle-lid-switch
18690 @item handle-lid-switch-docked
18692 @item handle-lid-switch-external-power
18694 @item power-key-ignore-inhibited?
18696 @item suspend-key-ignore-inhibited?
18698 @item hibernate-key-ignore-inhibited?
18700 @item lid-switch-ignore-inhibited?
18702 @item holdoff-timeout-seconds
18706 @item idle-action-seconds
18708 @item runtime-directory-size-percent
18710 @item runtime-directory-size
18714 @item suspend-state
18715 @code{("mem" "standby" "freeze")}
18718 @item hibernate-state
18720 @item hibernate-mode
18721 @code{("platform" "shutdown")}
18722 @item hybrid-sleep-state
18724 @item hybrid-sleep-mode
18725 @code{("suspend" "platform" "shutdown")}
18729 @deffn {Scheme Procedure} accountsservice-service @
18730 [#:accountsservice @var{accountsservice}]
18731 Return a service that runs AccountsService, a system service that can
18732 list available accounts, change their passwords, and so on.
18733 AccountsService integrates with PolicyKit to enable unprivileged users
18734 to acquire the capability to modify their system configuration.
18735 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
18736 accountsservice web site} for more information.
18738 The @var{accountsservice} keyword argument is the @code{accountsservice}
18739 package to expose as a service.
18742 @deffn {Scheme Procedure} polkit-service @
18743 [#:polkit @var{polkit}]
18744 Return a service that runs the
18745 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
18746 management service}, which allows system administrators to grant access to
18747 privileged operations in a structured way. By querying the Polkit service, a
18748 privileged system component can know when it should grant additional
18749 capabilities to ordinary users. For example, an ordinary user can be granted
18750 the capability to suspend the system if the user is logged in locally.
18753 @defvr {Scheme Variable} polkit-wheel-service
18754 Service that adds the @code{wheel} group as admins to the Polkit
18755 service. This makes it so that users in the @code{wheel} group are queried
18756 for their own passwords when performing administrative actions instead of
18757 @code{root}'s, similar to the behaviour used by @code{sudo}.
18760 @defvr {Scheme Variable} upower-service-type
18761 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
18762 system-wide monitor for power consumption and battery levels, with the given
18763 configuration settings.
18765 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
18766 notably used by GNOME.
18769 @deftp {Data Type} upower-configuration
18770 Data type representation the configuration for UPower.
18774 @item @code{upower} (default: @var{upower})
18775 Package to use for @code{upower}.
18777 @item @code{watts-up-pro?} (default: @code{#f})
18778 Enable the Watts Up Pro device.
18780 @item @code{poll-batteries?} (default: @code{#t})
18781 Enable polling the kernel for battery level changes.
18783 @item @code{ignore-lid?} (default: @code{#f})
18784 Ignore the lid state, this can be useful if it's incorrect on a device.
18786 @item @code{use-percentage-for-policy?} (default: @code{#f})
18787 Whether battery percentage based policy should be used. The default is to use
18788 the time left, change to @code{#t} to use the percentage.
18790 @item @code{percentage-low} (default: @code{10})
18791 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
18792 at which the battery is considered low.
18794 @item @code{percentage-critical} (default: @code{3})
18795 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
18796 at which the battery is considered critical.
18798 @item @code{percentage-action} (default: @code{2})
18799 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
18800 at which action will be taken.
18802 @item @code{time-low} (default: @code{1200})
18803 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
18804 seconds at which the battery is considered low.
18806 @item @code{time-critical} (default: @code{300})
18807 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
18808 seconds at which the battery is considered critical.
18810 @item @code{time-action} (default: @code{120})
18811 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
18812 seconds at which action will be taken.
18814 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
18815 The action taken when @code{percentage-action} or @code{time-action} is
18816 reached (depending on the configuration of @code{use-percentage-for-policy?}).
18818 Possible values are:
18828 @code{'hybrid-sleep}.
18834 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
18835 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
18836 UDisks}, a @dfn{disk management} daemon that provides user interfaces
18837 with notifications and ways to mount/unmount disks. Programs that talk
18838 to UDisks include the @command{udisksctl} command, part of UDisks, and
18839 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
18840 it will only be able to use the file-system utilities installed in the
18841 system profile. For example if you want to be able to mount NTFS
18842 file-systems in read and write fashion, you'll need to have
18843 @code{ntfs-3g} installed system-wide.
18846 @deffn {Scheme Variable} colord-service-type
18847 This is the type of the service that runs @command{colord}, a system
18848 service with a D-Bus
18849 interface to manage the color profiles of input and output devices such as
18850 screens and scanners. It is notably used by the GNOME Color Manager graphical
18851 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
18852 site} for more information.
18855 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
18856 Return a configuration allowing an application to access GeoClue
18857 location data. @var{name} is the Desktop ID of the application, without
18858 the @code{.desktop} part. If @var{allowed?} is true, the application
18859 will have access to location information by default. The boolean
18860 @var{system?} value indicates whether an application is a system component
18861 or not. Finally @var{users} is a list of UIDs of all users for which
18862 this application is allowed location info access. An empty users list
18863 means that all users are allowed.
18866 @cindex scanner access
18867 @deffn {Scheme Procedure} sane-service-type
18868 This service provides access to scanners @i{via}
18869 @uref{http://www.sane-project.org, SANE} by installing the necessary udev
18873 @defvr {Scheme Variable} %standard-geoclue-applications
18874 The standard list of well-known GeoClue application configurations,
18875 granting authority to the GNOME date-and-time utility to ask for the
18876 current location in order to set the time zone, and allowing the
18877 IceCat and Epiphany web browsers to request location information.
18878 IceCat and Epiphany both query the user before allowing a web page to
18879 know the user's location.
18882 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
18883 [#:whitelist '()] @
18884 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
18885 [#:submit-data? #f]
18886 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
18887 [#:submission-nick "geoclue"] @
18888 [#:applications %standard-geoclue-applications]
18889 Return a service that runs the GeoClue location service. This service
18890 provides a D-Bus interface to allow applications to request access to a
18891 user's physical location, and optionally to add information to online
18892 location databases. See
18893 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
18894 web site} for more information.
18897 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
18898 [@w{#:auto-enable? #f}]
18899 Return a service that runs the @command{bluetoothd} daemon, which
18900 manages all the Bluetooth devices and provides a number of D-Bus
18901 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
18902 powered automatically at boot, which can be useful when using a
18903 bluetooth keyboard or mouse.
18905 Users need to be in the @code{lp} group to access the D-Bus service.
18908 @defvr {Scheme Variable} gnome-keyring-service-type
18909 This is the type of the service that adds the
18910 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
18911 value is a @code{gnome-keyring-configuration} object (see below).
18913 This service adds the @code{gnome-keyring} package to the system profile
18914 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
18915 a user's login keyring when they log in or setting its password with passwd.
18918 @deftp {Data Type} gnome-keyring-configuration
18919 Configuration record for the GNOME Keyring service.
18922 @item @code{keyring} (default: @code{gnome-keyring})
18923 The GNOME keyring package to use.
18925 @item @code{pam-services}
18926 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
18927 services to extend, where @var{service} is the name of an existing
18928 service to extend and @var{kind} is one of @code{login} or
18931 If @code{login} is given, it adds an optional
18932 @code{pam_gnome_keyring.so} to the auth block without arguments and to
18933 the session block with @code{auto_start}. If @code{passwd} is given, it
18934 adds an optional @code{pam_gnome_keyring.so} to the password block
18937 By default, this field contains ``gdm-password'' with the value @code{login}
18938 and ``passwd'' is with the value @code{passwd}.
18943 @node Sound Services
18944 @subsection Sound Services
18946 @cindex sound support
18948 @cindex PulseAudio, sound support
18950 The @code{(gnu services sound)} module provides a service to configure the
18951 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
18952 preferred ALSA output driver.
18954 @deffn {Scheme Variable} alsa-service-type
18955 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
18956 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
18957 configuration file. The value for this type is a @command{alsa-configuration}
18958 record as in this example:
18961 (service alsa-service-type)
18964 See below for details about @code{alsa-configuration}.
18967 @deftp {Data Type} alsa-configuration
18968 Data type representing the configuration for @code{alsa-service}.
18971 @item @code{alsa-plugins} (default: @var{alsa-plugins})
18972 @code{alsa-plugins} package to use.
18974 @item @code{pulseaudio?} (default: @var{#t})
18975 Whether ALSA applications should transparently be made to use the
18976 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
18978 Using PulseAudio allows you to run several sound-producing applications
18979 at the same time and to individual control them @i{via}
18980 @command{pavucontrol}, among other things.
18982 @item @code{extra-options} (default: @var{""})
18983 String to append to the @file{/etc/asound.conf} file.
18988 Individual users who want to override the system configuration of ALSA can do
18989 it with the @file{~/.asoundrc} file:
18992 # In guix, we have to specify the absolute path for plugins.
18994 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
18997 # Routing ALSA to jack:
18998 # <http://jackaudio.org/faq/routing_alsa.html>.
19002 0 system:playback_1
19003 1 system:playback_2
19020 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
19023 @deffn {Scheme Variable} pulseaudio-service-type
19024 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
19025 sound server. It exists to allow system overrides of the default settings
19026 via @code{pulseaudio-configuration}, see below.
19029 This service overrides per-user configuration files. If you want
19030 PulseAudio to honor configuration files in @file{~/.config/pulse} you
19031 have to unset the environment variables @env{PULSE_CONFIG} and
19032 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
19036 This service on its own does not ensure, that the @code{pulseaudio} package
19037 exists on your machine. It merely adds configuration files for it, as
19038 detailed below. In the (admittedly unlikely) case, that you find yourself
19039 without a @code{pulseaudio} package, consider enabling it through the
19040 @code{alsa-service-type} above.
19044 @deftp {Data Type} pulseaudio-configuration
19045 Data type representing the configuration for @code{pulseaudio-service}.
19048 @item @code{client-conf} (default: @code{'()})
19049 List of settings to set in @file{client.conf}.
19050 Accepts a list of strings or a symbol-value pairs. A string will be
19051 inserted as-is with a newline added. A pair will be formatted as
19052 ``key = value'', again with a newline added.
19054 @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
19055 List of settings to set in @file{daemon.conf}, formatted just like
19058 @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
19059 Script file to use as @file{default.pa}.
19061 @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
19062 Script file to use as @file{system.pa}.
19066 @deffn {Scheme Variable} ladspa-service-type
19067 This service sets the @var{LADSPA_PATH} variable, so that programs, which
19068 respect it, e.g. PulseAudio, can load LADSPA plugins.
19070 The following example will setup the service to enable modules from the
19071 @code{swh-plugins} package:
19074 (service ladspa-service-type
19075 (ladspa-configuration (plugins (list swh-plugins))))
19078 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
19083 @node Database Services
19084 @subsection Database Services
19088 The @code{(gnu services databases)} module provides the following services.
19090 @subsubheading PostgreSQL
19092 The following example describes a PostgreSQL service with the default
19096 (service postgresql-service-type
19097 (postgresql-configuration
19098 (postgresql postgresql-10)))
19101 If the services fails to start, it may be due to an incompatible
19102 cluster already present in @var{data-directory}. Adjust it (or, if you
19103 don't need the cluster anymore, delete @var{data-directory}), then
19104 restart the service.
19106 Peer authentication is used by default and the @code{postgres} user
19107 account has no shell, which prevents the direct execution of @code{psql}
19108 commands as this user. To use @code{psql}, you can temporarily log in
19109 as @code{postgres} using a shell, create a PostgreSQL superuser with the
19110 same name as one of the system users and then create the associated
19114 sudo -u postgres -s /bin/sh
19115 createuser --interactive
19116 createdb $MY_USER_LOGIN # Replace appropriately.
19119 @deftp {Data Type} postgresql-configuration
19120 Data type representing the configuration for the
19121 @code{postgresql-service-type}.
19124 @item @code{postgresql}
19125 PostgreSQL package to use for the service.
19127 @item @code{port} (default: @code{5432})
19128 Port on which PostgreSQL should listen.
19130 @item @code{locale} (default: @code{"en_US.utf8"})
19131 Locale to use as the default when creating the database cluster.
19133 @item @code{config-file} (default: @code{(postgresql-config-file)})
19134 The configuration file to use when running PostgreSQL. The default
19135 behaviour uses the postgresql-config-file record with the default values
19138 @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
19139 Directory in which to store the data.
19141 @item @code{extension-packages} (default: @code{'()})
19142 @cindex postgresql extension-packages
19143 Additional extensions are loaded from packages listed in
19144 @var{extension-packages}. Extensions are available at runtime. For instance,
19145 to create a geographic database using the @code{postgis} extension, a user can
19146 configure the postgresql-service as in this example:
19150 (use-package-modules databases geo)
19154 ;; postgresql is required to run `psql' but postgis is not required for
19155 ;; proper operation.
19156 (packages (cons* postgresql %base-packages))
19159 (service postgresql-service-type
19160 (postgresql-configuration
19161 (postgresql postgresql-10)
19162 (extension-packages (list postgis))))
19166 Then the extension becomes visible and you can initialise an empty geographic
19167 database in this way:
19171 > create database postgistest;
19172 > \connect postgistest;
19173 > create extension postgis;
19174 > create extension postgis_topology;
19177 There is no need to add this field for contrib extensions such as hstore or
19178 dblink as they are already loadable by postgresql. This field is only
19179 required to add extensions provided by other packages.
19184 @deftp {Data Type} postgresql-config-file
19185 Data type representing the PostgreSQL configuration file. As shown in
19186 the following example, this can be used to customize the configuration
19187 of PostgreSQL. Note that you can use any G-expression or filename in
19188 place of this record, if you already have a configuration file you'd
19189 like to use for example.
19192 (service postgresql-service-type
19193 (postgresql-configuration
19195 (postgresql-config-file
19196 (log-destination "stderr")
19198 (plain-file "pg_hba.conf"
19200 local all all trust
19201 host all all 127.0.0.1/32 md5
19202 host all all ::1/128 md5"))
19204 '(("session_preload_libraries" "'auto_explain'")
19205 ("random_page_cost" "2")
19206 ("auto_explain.log_min_duration" "'100ms'")
19207 ("work_mem" "'500MB'")
19208 ("logging_collector" "on")
19209 ("log_directory" "'/var/log/postgresql'")))))))
19213 @item @code{log-destination} (default: @code{"syslog"})
19214 The logging method to use for PostgreSQL. Multiple values are accepted,
19215 separated by commas.
19217 @item @code{hba-file} (default: @code{%default-postgres-hba})
19218 Filename or G-expression for the host-based authentication
19221 @item @code{ident-file} (default: @code{%default-postgres-ident})
19222 Filename or G-expression for the user name mapping configuration.
19224 @item @code{extra-config} (default: @code{'()})
19225 List of additional keys and values to include in the PostgreSQL config
19226 file. Each entry in the list should be a list where the first element
19227 is the key, and the remaining elements are the values.
19232 @subsubheading MariaDB/MySQL
19234 @defvr {Scheme Variable} mysql-service-type
19235 This is the service type for a MySQL or MariaDB database server. Its value
19236 is a @code{mysql-configuration} object that specifies which package to use,
19237 as well as various settings for the @command{mysqld} daemon.
19240 @deftp {Data Type} mysql-configuration
19241 Data type representing the configuration of @var{mysql-service-type}.
19244 @item @code{mysql} (default: @var{mariadb})
19245 Package object of the MySQL database server, can be either @var{mariadb}
19248 For MySQL, a temporary root password will be displayed at activation time.
19249 For MariaDB, the root password is empty.
19251 @item @code{bind-address} (default: @code{"127.0.0.1"})
19252 The IP on which to listen for network connections. Use @code{"0.0.0.0"}
19253 to bind to all available network interfaces.
19255 @item @code{port} (default: @code{3306})
19256 TCP port on which the database server listens for incoming connections.
19258 @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
19259 Socket file to use for local (non-network) connections.
19261 @item @code{extra-content} (default: @code{""})
19262 Additional settings for the @file{my.cnf} configuration file.
19264 @item @code{auto-upgrade?} (default: @code{#t})
19265 Whether to automatically run @command{mysql_upgrade} after starting the
19266 service. This is necessary to upgrade the @dfn{system schema} after
19267 ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
19268 be disabled if you would rather do that manually.
19273 @subsubheading Memcached
19275 @defvr {Scheme Variable} memcached-service-type
19276 This is the service type for the @uref{https://memcached.org/,
19277 Memcached} service, which provides a distributed in memory cache. The
19278 value for the service type is a @code{memcached-configuration} object.
19282 (service memcached-service-type)
19285 @deftp {Data Type} memcached-configuration
19286 Data type representing the configuration of memcached.
19289 @item @code{memcached} (default: @code{memcached})
19290 The Memcached package to use.
19292 @item @code{interfaces} (default: @code{'("0.0.0.0")})
19293 Network interfaces on which to listen.
19295 @item @code{tcp-port} (default: @code{11211})
19296 Port on which to accept connections.
19298 @item @code{udp-port} (default: @code{11211})
19299 Port on which to accept UDP connections on, a value of 0 will disable
19300 listening on a UDP socket.
19302 @item @code{additional-options} (default: @code{'()})
19303 Additional command line options to pass to @code{memcached}.
19307 @subsubheading MongoDB
19309 @defvr {Scheme Variable} mongodb-service-type
19310 This is the service type for @uref{https://www.mongodb.com/, MongoDB}.
19311 The value for the service type is a @code{mongodb-configuration} object.
19315 (service mongodb-service-type)
19318 @deftp {Data Type} mongodb-configuration
19319 Data type representing the configuration of mongodb.
19322 @item @code{mongodb} (default: @code{mongodb})
19323 The MongoDB package to use.
19325 @item @code{config-file} (default: @code{%default-mongodb-configuration-file})
19326 The configuration file for MongoDB.
19328 @item @code{data-directory} (default: @code{"/var/lib/mongodb"})
19329 This value is used to create the directory, so that it exists and is
19330 owned by the mongodb user. It should match the data-directory which
19331 MongoDB is configured to use through the configuration file.
19335 @subsubheading Redis
19337 @defvr {Scheme Variable} redis-service-type
19338 This is the service type for the @uref{https://redis.io/, Redis}
19339 key/value store, whose value is a @code{redis-configuration} object.
19342 @deftp {Data Type} redis-configuration
19343 Data type representing the configuration of redis.
19346 @item @code{redis} (default: @code{redis})
19347 The Redis package to use.
19349 @item @code{bind} (default: @code{"127.0.0.1"})
19350 Network interface on which to listen.
19352 @item @code{port} (default: @code{6379})
19353 Port on which to accept connections on, a value of 0 will disable
19354 listening on a TCP socket.
19356 @item @code{working-directory} (default: @code{"/var/lib/redis"})
19357 Directory in which to store the database and related files.
19361 @node Mail Services
19362 @subsection Mail Services
19366 The @code{(gnu services mail)} module provides Guix service definitions
19367 for email services: IMAP, POP3, and LMTP servers, as well as mail
19368 transport agents (MTAs). Lots of acronyms! These services are detailed
19369 in the subsections below.
19371 @subsubheading Dovecot Service
19373 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
19374 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
19377 By default, Dovecot does not need much configuration; the default
19378 configuration object created by @code{(dovecot-configuration)} will
19379 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
19380 certificate will be generated for TLS-protected connections, though
19381 Dovecot will also listen on cleartext ports by default. There are a
19382 number of options, though, which mail administrators might need to change,
19383 and as is the case with other services, Guix allows the system
19384 administrator to specify these parameters via a uniform Scheme interface.
19386 For example, to specify that mail is located at @code{maildir~/.mail},
19387 one would instantiate the Dovecot service like this:
19390 (dovecot-service #:config
19391 (dovecot-configuration
19392 (mail-location "maildir:~/.mail")))
19395 The available configuration parameters follow. Each parameter
19396 definition is preceded by its type; for example, @samp{string-list foo}
19397 indicates that the @code{foo} parameter should be specified as a list of
19398 strings. There is also a way to specify the configuration as a string,
19399 if you have an old @code{dovecot.conf} file that you want to port over
19400 from some other system; see the end for more details.
19402 @c The following documentation was initially generated by
19403 @c (generate-documentation) in (gnu services mail). Manually maintained
19404 @c documentation is better, so we shouldn't hesitate to edit below as
19405 @c needed. However if the change you want to make to this documentation
19406 @c can be done in an automated way, it's probably easier to change
19407 @c (generate-documentation) than to make it below and have to deal with
19408 @c the churn as dovecot updates.
19410 Available @code{dovecot-configuration} fields are:
19412 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
19413 The dovecot package.
19416 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
19417 A list of IPs or hosts where to listen for connections. @samp{*}
19418 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
19419 interfaces. If you want to specify non-default ports or anything more
19420 complex, customize the address and port fields of the
19421 @samp{inet-listener} of the specific services you are interested in.
19424 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
19425 List of protocols we want to serve. Available protocols include
19426 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
19428 Available @code{protocol-configuration} fields are:
19430 @deftypevr {@code{protocol-configuration} parameter} string name
19431 The name of the protocol.
19434 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
19435 UNIX socket path to the master authentication server to find users.
19436 This is used by imap (for shared users) and lda.
19437 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
19440 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
19441 Space separated list of plugins to load.
19444 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
19445 Maximum number of IMAP connections allowed for a user from each IP
19446 address. NOTE: The username is compared case-sensitively.
19447 Defaults to @samp{10}.
19452 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
19453 List of services to enable. Available services include @samp{imap},
19454 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
19457 Available @code{service-configuration} fields are:
19459 @deftypevr {@code{service-configuration} parameter} string kind
19460 The service kind. Valid values include @code{director},
19461 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
19462 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
19463 @code{tcpwrap}, @code{quota-warning}, or anything else.
19466 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
19467 Listeners for the service. A listener is either a
19468 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
19469 an @code{inet-listener-configuration}.
19470 Defaults to @samp{()}.
19472 Available @code{unix-listener-configuration} fields are:
19474 @deftypevr {@code{unix-listener-configuration} parameter} string path
19475 Path to the file, relative to @code{base-dir} field. This is also used as
19479 @deftypevr {@code{unix-listener-configuration} parameter} string mode
19480 The access mode for the socket.
19481 Defaults to @samp{"0600"}.
19484 @deftypevr {@code{unix-listener-configuration} parameter} string user
19485 The user to own the socket.
19486 Defaults to @samp{""}.
19489 @deftypevr {@code{unix-listener-configuration} parameter} string group
19490 The group to own the socket.
19491 Defaults to @samp{""}.
19495 Available @code{fifo-listener-configuration} fields are:
19497 @deftypevr {@code{fifo-listener-configuration} parameter} string path
19498 Path to the file, relative to @code{base-dir} field. This is also used as
19502 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
19503 The access mode for the socket.
19504 Defaults to @samp{"0600"}.
19507 @deftypevr {@code{fifo-listener-configuration} parameter} string user
19508 The user to own the socket.
19509 Defaults to @samp{""}.
19512 @deftypevr {@code{fifo-listener-configuration} parameter} string group
19513 The group to own the socket.
19514 Defaults to @samp{""}.
19518 Available @code{inet-listener-configuration} fields are:
19520 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
19521 The protocol to listen for.
19524 @deftypevr {@code{inet-listener-configuration} parameter} string address
19525 The address on which to listen, or empty for all addresses.
19526 Defaults to @samp{""}.
19529 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
19530 The port on which to listen.
19533 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
19534 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
19536 Defaults to @samp{#t}.
19541 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
19542 Maximum number of simultaneous client connections per process. Once
19543 this number of connections is received, the next incoming connection
19544 will prompt Dovecot to spawn another process. If set to 0,
19545 @code{default-client-limit} is used instead.
19547 Defaults to @samp{0}.
19551 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
19552 Number of connections to handle before starting a new process.
19553 Typically the only useful values are 0 (unlimited) or 1. 1 is more
19554 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
19555 Defaults to @samp{1}.
19559 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
19560 Maximum number of processes that can exist for this service. If set to
19561 0, @code{default-process-limit} is used instead.
19563 Defaults to @samp{0}.
19567 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
19568 Number of processes to always keep waiting for more connections.
19569 Defaults to @samp{0}.
19572 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
19573 If you set @samp{service-count 0}, you probably need to grow
19575 Defaults to @samp{256000000}.
19580 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
19581 Dict configuration, as created by the @code{dict-configuration}
19584 Available @code{dict-configuration} fields are:
19586 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
19587 A list of key-value pairs that this dict should hold.
19588 Defaults to @samp{()}.
19593 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
19594 A list of passdb configurations, each one created by the
19595 @code{passdb-configuration} constructor.
19597 Available @code{passdb-configuration} fields are:
19599 @deftypevr {@code{passdb-configuration} parameter} string driver
19600 The driver that the passdb should use. Valid values include
19601 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
19603 Defaults to @samp{"pam"}.
19606 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
19607 Space separated list of arguments to the passdb driver.
19608 Defaults to @samp{""}.
19613 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
19614 List of userdb configurations, each one created by the
19615 @code{userdb-configuration} constructor.
19617 Available @code{userdb-configuration} fields are:
19619 @deftypevr {@code{userdb-configuration} parameter} string driver
19620 The driver that the userdb should use. Valid values include
19621 @samp{passwd} and @samp{static}.
19622 Defaults to @samp{"passwd"}.
19625 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
19626 Space separated list of arguments to the userdb driver.
19627 Defaults to @samp{""}.
19630 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
19631 Override fields from passwd.
19632 Defaults to @samp{()}.
19637 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
19638 Plug-in configuration, created by the @code{plugin-configuration}
19642 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
19643 List of namespaces. Each item in the list is created by the
19644 @code{namespace-configuration} constructor.
19646 Available @code{namespace-configuration} fields are:
19648 @deftypevr {@code{namespace-configuration} parameter} string name
19649 Name for this namespace.
19652 @deftypevr {@code{namespace-configuration} parameter} string type
19653 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
19654 Defaults to @samp{"private"}.
19657 @deftypevr {@code{namespace-configuration} parameter} string separator
19658 Hierarchy separator to use. You should use the same separator for
19659 all namespaces or some clients get confused. @samp{/} is usually a good
19660 one. The default however depends on the underlying mail storage
19662 Defaults to @samp{""}.
19665 @deftypevr {@code{namespace-configuration} parameter} string prefix
19666 Prefix required to access this namespace. This needs to be
19667 different for all namespaces. For example @samp{Public/}.
19668 Defaults to @samp{""}.
19671 @deftypevr {@code{namespace-configuration} parameter} string location
19672 Physical location of the mailbox. This is in the same format as
19673 mail_location, which is also the default for it.
19674 Defaults to @samp{""}.
19677 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
19678 There can be only one INBOX, and this setting defines which
19680 Defaults to @samp{#f}.
19683 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
19684 If namespace is hidden, it's not advertised to clients via NAMESPACE
19685 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
19686 useful when converting from another server with different namespaces
19687 which you want to deprecate but still keep working. For example you can
19688 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
19690 Defaults to @samp{#f}.
19693 @deftypevr {@code{namespace-configuration} parameter} boolean list?
19694 Show the mailboxes under this namespace with the LIST command. This
19695 makes the namespace visible for clients that do not support the NAMESPACE
19696 extension. The special @code{children} value lists child mailboxes, but
19697 hides the namespace prefix.
19698 Defaults to @samp{#t}.
19701 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
19702 Namespace handles its own subscriptions. If set to @code{#f}, the
19703 parent namespace handles them. The empty prefix should always have this
19705 Defaults to @samp{#t}.
19708 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
19709 List of predefined mailboxes in this namespace.
19710 Defaults to @samp{()}.
19712 Available @code{mailbox-configuration} fields are:
19714 @deftypevr {@code{mailbox-configuration} parameter} string name
19715 Name for this mailbox.
19718 @deftypevr {@code{mailbox-configuration} parameter} string auto
19719 @samp{create} will automatically create this mailbox.
19720 @samp{subscribe} will both create and subscribe to the mailbox.
19721 Defaults to @samp{"no"}.
19724 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
19725 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
19726 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
19727 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
19728 Defaults to @samp{()}.
19735 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
19736 Base directory where to store runtime data.
19737 Defaults to @samp{"/var/run/dovecot/"}.
19740 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
19741 Greeting message for clients.
19742 Defaults to @samp{"Dovecot ready."}.
19745 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
19746 List of trusted network ranges. Connections from these IPs are
19747 allowed to override their IP addresses and ports (for logging and for
19748 authentication checks). @samp{disable-plaintext-auth} is also ignored
19749 for these networks. Typically you would specify your IMAP proxy servers
19751 Defaults to @samp{()}.
19754 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
19755 List of login access check sockets (e.g.@: tcpwrap).
19756 Defaults to @samp{()}.
19759 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
19760 Show more verbose process titles (in ps). Currently shows user name
19761 and IP address. Useful for seeing who is actually using the IMAP
19762 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
19764 Defaults to @samp{#f}.
19767 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
19768 Should all processes be killed when Dovecot master process shuts down.
19769 Setting this to @code{#f} means that Dovecot can be upgraded without
19770 forcing existing client connections to close (although that could also
19771 be a problem if the upgrade is e.g.@: due to a security fix).
19772 Defaults to @samp{#t}.
19775 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
19776 If non-zero, run mail commands via this many connections to doveadm
19777 server, instead of running them directly in the same process.
19778 Defaults to @samp{0}.
19781 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
19782 UNIX socket or host:port used for connecting to doveadm server.
19783 Defaults to @samp{"doveadm-server"}.
19786 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
19787 List of environment variables that are preserved on Dovecot startup
19788 and passed down to all of its child processes. You can also give
19789 key=value pairs to always set specific settings.
19792 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
19793 Disable LOGIN command and all other plaintext authentications unless
19794 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
19795 matches the local IP (i.e.@: you're connecting from the same computer),
19796 the connection is considered secure and plaintext authentication is
19797 allowed. See also ssl=required setting.
19798 Defaults to @samp{#t}.
19801 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
19802 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
19803 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
19804 for caching to be used.
19805 Defaults to @samp{0}.
19808 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
19809 Time to live for cached data. After TTL expires the cached record
19810 is no longer used, *except* if the main database lookup returns internal
19811 failure. We also try to handle password changes automatically: If
19812 user's previous authentication was successful, but this one wasn't, the
19813 cache isn't used. For now this works only with plaintext
19815 Defaults to @samp{"1 hour"}.
19818 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
19819 TTL for negative hits (user not found, password mismatch).
19820 0 disables caching them completely.
19821 Defaults to @samp{"1 hour"}.
19824 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
19825 List of realms for SASL authentication mechanisms that need them.
19826 You can leave it empty if you don't want to support multiple realms.
19827 Many clients simply use the first one listed here, so keep the default
19829 Defaults to @samp{()}.
19832 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
19833 Default realm/domain to use if none was specified. This is used for
19834 both SASL realms and appending @@domain to username in plaintext
19836 Defaults to @samp{""}.
19839 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
19840 List of allowed characters in username. If the user-given username
19841 contains a character not listed in here, the login automatically fails.
19842 This is just an extra check to make sure user can't exploit any
19843 potential quote escaping vulnerabilities with SQL/LDAP databases. If
19844 you want to allow all characters, set this value to empty.
19845 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
19848 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
19849 Username character translations before it's looked up from
19850 databases. The value contains series of from -> to characters. For
19851 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
19852 translated to @samp{@@}.
19853 Defaults to @samp{""}.
19856 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
19857 Username formatting before it's looked up from databases. You can
19858 use the standard variables here, e.g.@: %Lu would lowercase the username,
19859 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
19860 change the @samp{@@} into @samp{-AT-}. This translation is done after
19861 @samp{auth-username-translation} changes.
19862 Defaults to @samp{"%Lu"}.
19865 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
19866 If you want to allow master users to log in by specifying the master
19867 username within the normal username string (i.e.@: not using SASL
19868 mechanism's support for it), you can specify the separator character
19869 here. The format is then <username><separator><master username>.
19870 UW-IMAP uses @samp{*} as the separator, so that could be a good
19872 Defaults to @samp{""}.
19875 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
19876 Username to use for users logging in with ANONYMOUS SASL
19878 Defaults to @samp{"anonymous"}.
19881 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
19882 Maximum number of dovecot-auth worker processes. They're used to
19883 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
19884 They're automatically created and destroyed as needed.
19885 Defaults to @samp{30}.
19888 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
19889 Host name to use in GSSAPI principal names. The default is to use
19890 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
19891 allow all keytab entries.
19892 Defaults to @samp{""}.
19895 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
19896 Kerberos keytab to use for the GSSAPI mechanism. Will use the
19897 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
19898 need to change the auth service to run as root to be able to read this
19900 Defaults to @samp{""}.
19903 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
19904 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
19905 and @samp{ntlm-auth} helper.
19906 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
19907 Defaults to @samp{#f}.
19910 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
19911 Path for Samba's @samp{ntlm-auth} helper binary.
19912 Defaults to @samp{"/usr/bin/ntlm_auth"}.
19915 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
19916 Time to delay before replying to failed authentications.
19917 Defaults to @samp{"2 secs"}.
19920 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
19921 Require a valid SSL client certificate or the authentication
19923 Defaults to @samp{#f}.
19926 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
19927 Take the username from client's SSL certificate, using
19928 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
19930 Defaults to @samp{#f}.
19933 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
19934 List of wanted authentication mechanisms. Supported mechanisms are:
19935 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
19936 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
19937 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
19938 @samp{disable-plaintext-auth} setting.
19941 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
19942 List of IPs or hostnames to all director servers, including ourself.
19943 Ports can be specified as ip:port. The default port is the same as what
19944 director service's @samp{inet-listener} is using.
19945 Defaults to @samp{()}.
19948 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
19949 List of IPs or hostnames to all backend mail servers. Ranges are
19950 allowed too, like 10.0.0.10-10.0.0.30.
19951 Defaults to @samp{()}.
19954 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
19955 How long to redirect users to a specific server after it no longer
19956 has any connections.
19957 Defaults to @samp{"15 min"}.
19960 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
19961 How the username is translated before being hashed. Useful values
19962 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
19963 are shared within domain.
19964 Defaults to @samp{"%Lu"}.
19967 @deftypevr {@code{dovecot-configuration} parameter} string log-path
19968 Log file to use for error messages. @samp{syslog} logs to syslog,
19969 @samp{/dev/stderr} logs to stderr.
19970 Defaults to @samp{"syslog"}.
19973 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
19974 Log file to use for informational messages. Defaults to
19976 Defaults to @samp{""}.
19979 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
19980 Log file to use for debug messages. Defaults to
19981 @samp{info-log-path}.
19982 Defaults to @samp{""}.
19985 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
19986 Syslog facility to use if you're logging to syslog. Usually if you
19987 don't want to use @samp{mail}, you'll use local0..local7. Also other
19988 standard facilities are supported.
19989 Defaults to @samp{"mail"}.
19992 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
19993 Log unsuccessful authentication attempts and the reasons why they
19995 Defaults to @samp{#f}.
19998 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
19999 In case of password mismatches, log the attempted password. Valid
20000 values are no, plain and sha1. sha1 can be useful for detecting brute
20001 force password attempts vs. user simply trying the same password over
20002 and over again. You can also truncate the value to n chars by appending
20003 ":n" (e.g.@: sha1:6).
20004 Defaults to @samp{"no"}.
20007 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
20008 Even more verbose logging for debugging purposes. Shows for example
20010 Defaults to @samp{#f}.
20013 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
20014 In case of password mismatches, log the passwords and used scheme so
20015 the problem can be debugged. Enabling this also enables
20017 Defaults to @samp{#f}.
20020 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
20021 Enable mail process debugging. This can help you figure out why
20022 Dovecot isn't finding your mails.
20023 Defaults to @samp{#f}.
20026 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
20027 Show protocol level SSL errors.
20028 Defaults to @samp{#f}.
20031 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
20032 Prefix for each line written to log file. % codes are in
20033 strftime(3) format.
20034 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
20037 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
20038 List of elements we want to log. The elements which have a
20039 non-empty variable value are joined together to form a comma-separated
20043 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
20044 Login log format. %s contains @samp{login-log-format-elements}
20045 string, %$ contains the data we want to log.
20046 Defaults to @samp{"%$: %s"}.
20049 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
20050 Log prefix for mail processes. See doc/wiki/Variables.txt for list
20051 of possible variables you can use.
20052 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
20055 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
20056 Format to use for logging mail deliveries. You can use variables:
20059 Delivery status message (e.g.@: @samp{saved to INBOX})
20071 Defaults to @samp{"msgid=%m: %$"}.
20074 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
20075 Location for users' mailboxes. The default is empty, which means
20076 that Dovecot tries to find the mailboxes automatically. This won't work
20077 if the user doesn't yet have any mail, so you should explicitly tell
20078 Dovecot the full location.
20080 If you're using mbox, giving a path to the INBOX
20081 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
20082 where the other mailboxes are kept. This is called the @emph{root mail
20083 directory}, and it must be the first path given in the
20084 @samp{mail-location} setting.
20086 There are a few special variables you can use, e.g.:
20092 user part in user@@domain, same as %u if there's no domain
20094 domain part in user@@domain, empty if there's no domain
20099 See doc/wiki/Variables.txt for full list. Some examples:
20101 @item maildir:~/Maildir
20102 @item mbox:~/mail:INBOX=/var/mail/%u
20103 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
20105 Defaults to @samp{""}.
20108 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
20109 System user and group used to access mails. If you use multiple,
20110 userdb can override these by returning uid or gid fields. You can use
20111 either numbers or names. <doc/wiki/UserIds.txt>.
20112 Defaults to @samp{""}.
20115 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
20117 Defaults to @samp{""}.
20120 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
20121 Group to enable temporarily for privileged operations. Currently
20122 this is used only with INBOX when either its initial creation or
20123 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
20125 Defaults to @samp{""}.
20128 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
20129 Grant access to these supplementary groups for mail processes.
20130 Typically these are used to set up access to shared mailboxes. Note
20131 that it may be dangerous to set these if users can create symlinks
20132 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
20133 could allow a user to delete others' mailboxes, or @code{ln -s
20134 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
20138 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
20139 Allow full file system access to clients. There's no access checks
20140 other than what the operating system does for the active UID/GID. It
20141 works with both maildir and mboxes, allowing you to prefix mailboxes
20142 names with e.g.@: @file{/path/} or @file{~user/}.
20143 Defaults to @samp{#f}.
20146 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
20147 Don't use @code{mmap()} at all. This is required if you store indexes to
20148 shared file systems (NFS or clustered file system).
20149 Defaults to @samp{#f}.
20152 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
20153 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
20154 supports @samp{O_EXCL} since version 3, so this should be safe to use
20155 nowadays by default.
20156 Defaults to @samp{#t}.
20159 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
20160 When to use fsync() or fdatasync() calls:
20163 Whenever necessary to avoid losing important data
20165 Useful with e.g.@: NFS when @code{write()}s are delayed
20167 Never use it (best performance, but crashes can lose data).
20169 Defaults to @samp{"optimized"}.
20172 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
20173 Mail storage exists in NFS. Set this to yes to make Dovecot flush
20174 NFS caches whenever needed. If you're using only a single mail server
20176 Defaults to @samp{#f}.
20179 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
20180 Mail index files also exist in NFS. Setting this to yes requires
20181 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
20182 Defaults to @samp{#f}.
20185 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
20186 Locking method for index files. Alternatives are fcntl, flock and
20187 dotlock. Dotlocking uses some tricks which may create more disk I/O
20188 than other locking methods. NFS users: flock doesn't work, remember to
20189 change @samp{mmap-disable}.
20190 Defaults to @samp{"fcntl"}.
20193 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
20194 Directory in which LDA/LMTP temporarily stores incoming mails >128
20196 Defaults to @samp{"/tmp"}.
20199 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
20200 Valid UID range for users. This is mostly to make sure that users can't
20201 log in as daemons or other system users. Note that denying root logins is
20202 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
20204 Defaults to @samp{500}.
20207 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
20209 Defaults to @samp{0}.
20212 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
20213 Valid GID range for users. Users having non-valid GID as primary group ID
20214 aren't allowed to log in. If user belongs to supplementary groups with
20215 non-valid GIDs, those groups are not set.
20216 Defaults to @samp{1}.
20219 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
20221 Defaults to @samp{0}.
20224 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
20225 Maximum allowed length for mail keyword name. It's only forced when
20226 trying to create new keywords.
20227 Defaults to @samp{50}.
20230 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
20231 List of directories under which chrooting is allowed for mail
20232 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
20233 too). This setting doesn't affect @samp{login-chroot}
20234 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
20235 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
20236 which local users can modify, that may lead to root exploit. Usually
20237 this should be done only if you don't allow shell access for users.
20238 <doc/wiki/Chrooting.txt>.
20239 Defaults to @samp{()}.
20242 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
20243 Default chroot directory for mail processes. This can be overridden
20244 for specific users in user database by giving @samp{/./} in user's home
20245 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
20246 there is no real need to do chrooting, Dovecot doesn't allow users to
20247 access files outside their mail directory anyway. If your home
20248 directories are prefixed with the chroot directory, append @samp{/.} to
20249 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
20250 Defaults to @samp{""}.
20253 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
20254 UNIX socket path to master authentication server to find users.
20255 This is used by imap (for shared users) and lda.
20256 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
20259 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
20260 Directory where to look up mail plugins.
20261 Defaults to @samp{"/usr/lib/dovecot"}.
20264 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
20265 List of plugins to load for all services. Plugins specific to IMAP,
20266 LDA, etc.@: are added to this list in their own .conf files.
20267 Defaults to @samp{()}.
20270 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
20271 The minimum number of mails in a mailbox before updates are done to
20272 cache file. This allows optimizing Dovecot's behavior to do less disk
20273 writes at the cost of more disk reads.
20274 Defaults to @samp{0}.
20277 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
20278 When IDLE command is running, mailbox is checked once in a while to
20279 see if there are any new mails or other changes. This setting defines
20280 the minimum time to wait between those checks. Dovecot can also use
20281 dnotify, inotify and kqueue to find out immediately when changes
20283 Defaults to @samp{"30 secs"}.
20286 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
20287 Save mails with CR+LF instead of plain LF. This makes sending those
20288 mails take less CPU, especially with sendfile() syscall with Linux and
20289 FreeBSD. But it also creates a bit more disk I/O which may just make it
20290 slower. Also note that if other software reads the mboxes/maildirs,
20291 they may handle the extra CRs wrong and cause problems.
20292 Defaults to @samp{#f}.
20295 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
20296 By default LIST command returns all entries in maildir beginning
20297 with a dot. Enabling this option makes Dovecot return only entries
20298 which are directories. This is done by stat()ing each entry, so it
20299 causes more disk I/O.
20300 (For systems setting struct @samp{dirent->d_type} this check is free
20301 and it's done always regardless of this setting).
20302 Defaults to @samp{#f}.
20305 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
20306 When copying a message, do it with hard links whenever possible.
20307 This makes the performance much better, and it's unlikely to have any
20309 Defaults to @samp{#t}.
20312 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
20313 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
20314 directory only when its mtime changes unexpectedly or when we can't find
20315 the mail otherwise.
20316 Defaults to @samp{#f}.
20319 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
20320 Which locking methods to use for locking mbox. There are four
20325 Create <mailbox>.lock file. This is the oldest and most NFS-safe
20326 solution. If you want to use /var/mail/ like directory, the users will
20327 need write access to that directory.
20329 Same as dotlock, but if it fails because of permissions or because there
20330 isn't enough disk space, just skip it.
20332 Use this if possible. Works with NFS too if lockd is used.
20334 May not exist in all systems. Doesn't work with NFS.
20336 May not exist in all systems. Doesn't work with NFS.
20339 You can use multiple locking methods; if you do the order they're declared
20340 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
20341 locking methods as well. Some operating systems don't allow using some of
20342 them simultaneously.
20345 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
20349 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
20350 Maximum time to wait for lock (all of them) before aborting.
20351 Defaults to @samp{"5 mins"}.
20354 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
20355 If dotlock exists but the mailbox isn't modified in any way,
20356 override the lock file after this much time.
20357 Defaults to @samp{"2 mins"}.
20360 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
20361 When mbox changes unexpectedly we have to fully read it to find out
20362 what changed. If the mbox is large this can take a long time. Since
20363 the change is usually just a newly appended mail, it'd be faster to
20364 simply read the new mails. If this setting is enabled, Dovecot does
20365 this but still safely fallbacks to re-reading the whole mbox file
20366 whenever something in mbox isn't how it's expected to be. The only real
20367 downside to this setting is that if some other MUA changes message
20368 flags, Dovecot doesn't notice it immediately. Note that a full sync is
20369 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
20370 Defaults to @samp{#t}.
20373 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
20374 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
20375 EXAMINE, EXPUNGE or CHECK commands. If this is set,
20376 @samp{mbox-dirty-syncs} is ignored.
20377 Defaults to @samp{#f}.
20380 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
20381 Delay writing mbox headers until doing a full write sync (EXPUNGE
20382 and CHECK commands and when closing the mailbox). This is especially
20383 useful for POP3 where clients often delete all mails. The downside is
20384 that our changes aren't immediately visible to other MUAs.
20385 Defaults to @samp{#t}.
20388 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
20389 If mbox size is smaller than this (e.g.@: 100k), don't write index
20390 files. If an index file already exists it's still read, just not
20392 Defaults to @samp{0}.
20395 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
20396 Maximum dbox file size until it's rotated.
20397 Defaults to @samp{10000000}.
20400 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
20401 Maximum dbox file age until it's rotated. Typically in days. Day
20402 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
20404 Defaults to @samp{"1d"}.
20407 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
20408 When creating new mdbox files, immediately preallocate their size to
20409 @samp{mdbox-rotate-size}. This setting currently works only in Linux
20410 with some file systems (ext4, xfs).
20411 Defaults to @samp{#f}.
20414 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
20415 sdbox and mdbox support saving mail attachments to external files,
20416 which also allows single instance storage for them. Other backends
20417 don't support this for now.
20419 WARNING: This feature hasn't been tested much yet. Use at your own risk.
20421 Directory root where to store mail attachments. Disabled, if empty.
20422 Defaults to @samp{""}.
20425 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
20426 Attachments smaller than this aren't saved externally. It's also
20427 possible to write a plugin to disable saving specific attachments
20429 Defaults to @samp{128000}.
20432 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
20433 File system backend to use for saving attachments:
20436 No SiS done by Dovecot (but this might help FS's own deduplication)
20438 SiS with immediate byte-by-byte comparison during saving
20439 @item sis-queue posix
20440 SiS with delayed comparison and deduplication.
20442 Defaults to @samp{"sis posix"}.
20445 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
20446 Hash format to use in attachment filenames. You can add any text and
20447 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
20448 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
20449 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
20450 Defaults to @samp{"%@{sha1@}"}.
20453 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
20455 Defaults to @samp{100}.
20458 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
20460 Defaults to @samp{1000}.
20463 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
20464 Default VSZ (virtual memory size) limit for service processes.
20465 This is mainly intended to catch and kill processes that leak memory
20466 before they eat up everything.
20467 Defaults to @samp{256000000}.
20470 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
20471 Login user is internally used by login processes. This is the most
20472 untrusted user in Dovecot system. It shouldn't have access to anything
20474 Defaults to @samp{"dovenull"}.
20477 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
20478 Internal user is used by unprivileged processes. It should be
20479 separate from login user, so that login processes can't disturb other
20481 Defaults to @samp{"dovecot"}.
20484 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
20485 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
20486 Defaults to @samp{"required"}.
20489 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
20490 PEM encoded X.509 SSL/TLS certificate (public key).
20491 Defaults to @samp{"</etc/dovecot/default.pem"}.
20494 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
20495 PEM encoded SSL/TLS private key. The key is opened before
20496 dropping root privileges, so keep the key file unreadable by anyone but
20498 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
20501 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
20502 If key file is password protected, give the password here.
20503 Alternatively give it when starting dovecot with -p parameter. Since
20504 this file is often world-readable, you may want to place this setting
20505 instead to a different.
20506 Defaults to @samp{""}.
20509 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
20510 PEM encoded trusted certificate authority. Set this only if you
20511 intend to use @samp{ssl-verify-client-cert? #t}. The file should
20512 contain the CA certificate(s) followed by the matching
20513 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
20514 Defaults to @samp{""}.
20517 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
20518 Require that CRL check succeeds for client certificates.
20519 Defaults to @samp{#t}.
20522 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
20523 Request client to send a certificate. If you also want to require
20524 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
20525 Defaults to @samp{#f}.
20528 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
20529 Which field from certificate to use for username. commonName and
20530 x500UniqueIdentifier are the usual choices. You'll also need to set
20531 @samp{auth-ssl-username-from-cert? #t}.
20532 Defaults to @samp{"commonName"}.
20535 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
20536 Minimum SSL protocol version to accept.
20537 Defaults to @samp{"TLSv1"}.
20540 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
20541 SSL ciphers to use.
20542 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
20545 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
20546 SSL crypto device to use, for valid values run "openssl engine".
20547 Defaults to @samp{""}.
20550 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
20551 Address to use when sending rejection mails.
20552 %d expands to recipient domain.
20553 Defaults to @samp{"postmaster@@%d"}.
20556 @deftypevr {@code{dovecot-configuration} parameter} string hostname
20557 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
20558 and in LMTP replies. Default is the system's real hostname@@domain.
20559 Defaults to @samp{""}.
20562 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
20563 If user is over quota, return with temporary failure instead of
20565 Defaults to @samp{#f}.
20568 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
20569 Binary to use for sending mails.
20570 Defaults to @samp{"/usr/sbin/sendmail"}.
20573 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
20574 If non-empty, send mails via this SMTP host[:port] instead of
20576 Defaults to @samp{""}.
20579 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
20580 Subject: header to use for rejection mails. You can use the same
20581 variables as for @samp{rejection-reason} below.
20582 Defaults to @samp{"Rejected: %s"}.
20585 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
20586 Human readable error message for rejection mails. You can use
20599 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
20602 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
20603 Delimiter character between local-part and detail in email
20605 Defaults to @samp{"+"}.
20608 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
20609 Header where the original recipient address (SMTP's RCPT TO:
20610 address) is taken from if not available elsewhere. With dovecot-lda -a
20611 parameter overrides this. A commonly used header for this is
20613 Defaults to @samp{""}.
20616 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
20617 Should saving a mail to a nonexistent mailbox automatically create
20619 Defaults to @samp{#f}.
20622 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
20623 Should automatically created mailboxes be also automatically
20625 Defaults to @samp{#f}.
20628 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
20629 Maximum IMAP command line length. Some clients generate very long
20630 command lines with huge mailboxes, so you may need to raise this if you
20631 get "Too long argument" or "IMAP command line too large" errors
20633 Defaults to @samp{64000}.
20636 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
20637 IMAP logout format string:
20640 total number of bytes read from client
20642 total number of bytes sent to client.
20644 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
20645 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@}"}.
20648 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
20649 Override the IMAP CAPABILITY response. If the value begins with '+',
20650 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
20651 Defaults to @samp{""}.
20654 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
20655 How long to wait between "OK Still here" notifications when client
20657 Defaults to @samp{"2 mins"}.
20660 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
20661 ID field names and values to send to clients. Using * as the value
20662 makes Dovecot use the default value. The following fields have default
20663 values currently: name, version, os, os-version, support-url,
20665 Defaults to @samp{""}.
20668 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
20669 ID fields sent by client to log. * means everything.
20670 Defaults to @samp{""}.
20673 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
20674 Workarounds for various client bugs:
20677 @item delay-newmail
20678 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
20679 CHECK commands. Some clients ignore them otherwise, for example OSX
20680 Mail (<v2.1). Outlook Express breaks more badly though, without this it
20681 may show user "Message no longer in server" errors. Note that OE6
20682 still breaks even with this workaround if synchronization is set to
20685 @item tb-extra-mailbox-sep
20686 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
20687 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
20688 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
20690 @item tb-lsub-flags
20691 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
20692 This makes Thunderbird realize they aren't selectable and show them
20693 greyed out, instead of only later giving "not selectable" popup error.
20695 Defaults to @samp{()}.
20698 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
20699 Host allowed in URLAUTH URLs sent by client. "*" allows all.
20700 Defaults to @samp{""}.
20704 Whew! Lots of configuration options. The nice thing about it though is
20705 that Guix has a complete interface to Dovecot's configuration
20706 language. This allows not only a nice way to declare configurations,
20707 but also offers reflective capabilities as well: users can write code to
20708 inspect and transform configurations from within Scheme.
20710 However, it could be that you just want to get a @code{dovecot.conf} up
20711 and running. In that case, you can pass an
20712 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
20713 @code{dovecot-service}. As its name indicates, an opaque configuration
20714 does not have easy reflective capabilities.
20716 Available @code{opaque-dovecot-configuration} fields are:
20718 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
20719 The dovecot package.
20722 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
20723 The contents of the @code{dovecot.conf}, as a string.
20726 For example, if your @code{dovecot.conf} is just the empty string, you
20727 could instantiate a dovecot service like this:
20730 (dovecot-service #:config
20731 (opaque-dovecot-configuration
20735 @subsubheading OpenSMTPD Service
20737 @deffn {Scheme Variable} opensmtpd-service-type
20738 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
20739 service, whose value should be an @code{opensmtpd-configuration} object
20740 as in this example:
20743 (service opensmtpd-service-type
20744 (opensmtpd-configuration
20745 (config-file (local-file "./my-smtpd.conf"))))
20749 @deftp {Data Type} opensmtpd-configuration
20750 Data type representing the configuration of opensmtpd.
20753 @item @code{package} (default: @var{opensmtpd})
20754 Package object of the OpenSMTPD SMTP server.
20756 @item @code{config-file} (default: @code{%default-opensmtpd-file})
20757 File-like object of the OpenSMTPD configuration file to use. By default
20758 it listens on the loopback network interface, and allows for mail from
20759 users and daemons on the local machine, as well as permitting email to
20760 remote servers. Run @command{man smtpd.conf} for more information.
20765 @subsubheading Exim Service
20767 @cindex mail transfer agent (MTA)
20768 @cindex MTA (mail transfer agent)
20771 @deffn {Scheme Variable} exim-service-type
20772 This is the type of the @uref{https://exim.org, Exim} mail transfer
20773 agent (MTA), whose value should be an @code{exim-configuration} object
20774 as in this example:
20777 (service exim-service-type
20778 (exim-configuration
20779 (config-file (local-file "./my-exim.conf"))))
20783 In order to use an @code{exim-service-type} service you must also have a
20784 @code{mail-aliases-service-type} service present in your
20785 @code{operating-system} (even if it has no aliases).
20787 @deftp {Data Type} exim-configuration
20788 Data type representing the configuration of exim.
20791 @item @code{package} (default: @var{exim})
20792 Package object of the Exim server.
20794 @item @code{config-file} (default: @code{#f})
20795 File-like object of the Exim configuration file to use. If its value is
20796 @code{#f} then use the default configuration file from the package
20797 provided in @code{package}. The resulting configuration file is loaded
20798 after setting the @code{exim_user} and @code{exim_group} configuration
20804 @subsubheading Getmail service
20809 @deffn {Scheme Variable} getmail-service-type
20810 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
20811 mail retriever, whose value should be an @code{getmail-configuration}.
20814 Available @code{getmail-configuration} fields are:
20816 @deftypevr {@code{getmail-configuration} parameter} symbol name
20817 A symbol to identify the getmail service.
20819 Defaults to @samp{"unset"}.
20823 @deftypevr {@code{getmail-configuration} parameter} package package
20824 The getmail package to use.
20828 @deftypevr {@code{getmail-configuration} parameter} string user
20829 The user to run getmail as.
20831 Defaults to @samp{"getmail"}.
20835 @deftypevr {@code{getmail-configuration} parameter} string group
20836 The group to run getmail as.
20838 Defaults to @samp{"getmail"}.
20842 @deftypevr {@code{getmail-configuration} parameter} string directory
20843 The getmail directory to use.
20845 Defaults to @samp{"/var/lib/getmail/default"}.
20849 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
20850 The getmail configuration file to use.
20852 Available @code{getmail-configuration-file} fields are:
20854 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
20855 What mail account to retrieve mail from, and how to access that account.
20857 Available @code{getmail-retriever-configuration} fields are:
20859 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
20860 The type of mail retriever to use. Valid values include @samp{passwd}
20863 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
20867 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
20868 Username to login to the mail server with.
20870 Defaults to @samp{unset}.
20874 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
20875 Username to login to the mail server with.
20877 Defaults to @samp{unset}.
20881 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
20882 Port number to connect to.
20884 Defaults to @samp{#f}.
20888 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
20889 Override fields from passwd.
20891 Defaults to @samp{""}.
20895 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
20896 Override fields from passwd.
20898 Defaults to @samp{()}.
20902 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
20903 PEM-formatted key file to use for the TLS negotiation.
20905 Defaults to @samp{""}.
20909 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
20910 PEM-formatted certificate file to use for the TLS negotiation.
20912 Defaults to @samp{""}.
20916 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
20917 CA certificates to use.
20919 Defaults to @samp{""}.
20923 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
20924 Extra retriever parameters.
20926 Defaults to @samp{()}.
20932 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
20933 What to do with retrieved messages.
20935 Available @code{getmail-destination-configuration} fields are:
20937 @deftypevr {@code{getmail-destination-configuration} parameter} string type
20938 The type of mail destination. Valid values include @samp{Maildir},
20939 @samp{Mboxrd} and @samp{MDA_external}.
20941 Defaults to @samp{unset}.
20945 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
20946 The path option for the mail destination. The behaviour depends on the
20949 Defaults to @samp{""}.
20953 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
20954 Extra destination parameters
20956 Defaults to @samp{()}.
20962 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
20965 Available @code{getmail-options-configuration} fields are:
20967 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
20968 If set to @samp{0}, getmail will only print warnings and errors. A
20969 value of @samp{1} means that messages will be printed about retrieving
20970 and deleting messages. If set to @samp{2}, getmail will print messages
20971 about each of it's actions.
20973 Defaults to @samp{1}.
20977 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
20978 If true, getmail will retrieve all available messages. Otherwise it
20979 will only retrieve messages it hasn't seen previously.
20981 Defaults to @samp{#t}.
20985 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
20986 If set to true, messages will be deleted from the server after
20987 retrieving and successfully delivering them. Otherwise, messages will
20988 be left on the server.
20990 Defaults to @samp{#f}.
20994 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
20995 Getmail will delete messages this number of days after seeing them, if
20996 they have been delivered. This means messages will be left on the
20997 server this number of days after delivering them. A value of @samp{0}
20998 disabled this feature.
21000 Defaults to @samp{0}.
21004 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
21005 Delete messages larger than this of bytes after retrieving them, even if
21006 the delete and delete-after options are disabled. A value of @samp{0}
21007 disables this feature.
21009 Defaults to @samp{0}.
21013 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
21014 Retrieve messages totalling up to this number of bytes before closing
21015 the session with the server. A value of @samp{0} disables this feature.
21017 Defaults to @samp{0}.
21021 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
21022 Don't retrieve messages larger than this number of bytes. A value of
21023 @samp{0} disables this feature.
21025 Defaults to @samp{0}.
21029 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
21030 If true, getmail will add a Delivered-To header to messages.
21032 Defaults to @samp{#t}.
21036 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
21037 If set, getmail adds a Received header to the messages.
21039 Defaults to @samp{#t}.
21043 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
21044 Getmail will record a log of its actions to the named file. A value of
21045 @samp{""} disables this feature.
21047 Defaults to @samp{""}.
21051 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
21052 If true, getmail will record a log of its actions using the system
21055 Defaults to @samp{#f}.
21059 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
21060 If true, getmail will log information about messages not retrieved and
21061 the reason for not retrieving them, as well as starting and ending
21064 Defaults to @samp{#f}.
21068 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
21069 Extra options to include.
21071 Defaults to @samp{()}.
21079 @deftypevr {@code{getmail-configuration} parameter} list idle
21080 A list of mailboxes that getmail should wait on the server for new mail
21081 notifications. This depends on the server supporting the IDLE
21084 Defaults to @samp{()}.
21088 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
21089 Environment variables to set for getmail.
21091 Defaults to @samp{()}.
21095 @subsubheading Mail Aliases Service
21097 @cindex email aliases
21098 @cindex aliases, for email addresses
21100 @deffn {Scheme Variable} mail-aliases-service-type
21101 This is the type of the service which provides @code{/etc/aliases},
21102 specifying how to deliver mail to users on this system.
21105 (service mail-aliases-service-type
21106 '(("postmaster" "bob")
21107 ("bob" "bob@@example.com" "bob@@example2.com")))
21111 The configuration for a @code{mail-aliases-service-type} service is an
21112 association list denoting how to deliver mail that comes to this
21113 system. Each entry is of the form @code{(alias addresses ...)}, with
21114 @code{alias} specifying the local alias and @code{addresses} specifying
21115 where to deliver this user's mail.
21117 The aliases aren't required to exist as users on the local system. In
21118 the above example, there doesn't need to be a @code{postmaster} entry in
21119 the @code{operating-system}'s @code{user-accounts} in order to deliver
21120 the @code{postmaster} mail to @code{bob} (which subsequently would
21121 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
21123 @subsubheading GNU Mailutils IMAP4 Daemon
21124 @cindex GNU Mailutils IMAP4 Daemon
21126 @deffn {Scheme Variable} imap4d-service-type
21127 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
21128 mailutils, GNU Mailutils Manual}), whose value should be an
21129 @code{imap4d-configuration} object as in this example:
21132 (service imap4d-service-type
21133 (imap4d-configuration
21134 (config-file (local-file "imap4d.conf"))))
21138 @deftp {Data Type} imap4d-configuration
21139 Data type representing the configuration of @command{imap4d}.
21142 @item @code{package} (default: @code{mailutils})
21143 The package that provides @command{imap4d}.
21145 @item @code{config-file} (default: @code{%default-imap4d-config-file})
21146 File-like object of the configuration file to use, by default it will listen
21147 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
21148 Mailutils Manual}, for details.
21153 @node Messaging Services
21154 @subsection Messaging Services
21159 The @code{(gnu services messaging)} module provides Guix service
21160 definitions for messaging services. Currently it provides the following
21163 @subsubheading Prosody Service
21165 @deffn {Scheme Variable} prosody-service-type
21166 This is the type for the @uref{https://prosody.im, Prosody XMPP
21167 communication server}. Its value must be a @code{prosody-configuration}
21168 record as in this example:
21171 (service prosody-service-type
21172 (prosody-configuration
21173 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
21176 (int-component-configuration
21177 (hostname "conference.example.net")
21179 (mod-muc (mod-muc-configuration)))))
21182 (virtualhost-configuration
21183 (domain "example.net"))))))
21186 See below for details about @code{prosody-configuration}.
21190 By default, Prosody does not need much configuration. Only one
21191 @code{virtualhosts} field is needed: it specifies the domain you wish
21194 You can perform various sanity checks on the generated configuration
21195 with the @code{prosodyctl check} command.
21197 Prosodyctl will also help you to import certificates from the
21198 @code{letsencrypt} directory so that the @code{prosody} user can access
21199 them. See @url{https://prosody.im/doc/letsencrypt}.
21202 prosodyctl --root cert import /etc/letsencrypt/live
21205 The available configuration parameters follow. Each parameter
21206 definition is preceded by its type; for example, @samp{string-list foo}
21207 indicates that the @code{foo} parameter should be specified as a list of
21208 strings. Types starting with @code{maybe-} denote parameters that won't
21209 show up in @code{prosody.cfg.lua} when their value is @code{'disabled}.
21211 There is also a way to specify the configuration as a string, if you
21212 have an old @code{prosody.cfg.lua} file that you want to port over from
21213 some other system; see the end for more details.
21215 The @code{file-object} type designates either a file-like object
21216 (@pxref{G-Expressions, file-like objects}) or a file name.
21218 @c The following documentation was initially generated by
21219 @c (generate-documentation) in (gnu services messaging). Manually maintained
21220 @c documentation is better, so we shouldn't hesitate to edit below as
21221 @c needed. However if the change you want to make to this documentation
21222 @c can be done in an automated way, it's probably easier to change
21223 @c (generate-documentation) than to make it below and have to deal with
21224 @c the churn as Prosody updates.
21226 Available @code{prosody-configuration} fields are:
21228 @deftypevr {@code{prosody-configuration} parameter} package prosody
21229 The Prosody package.
21232 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
21233 Location of the Prosody data storage directory. See
21234 @url{https://prosody.im/doc/configure}.
21235 Defaults to @samp{"/var/lib/prosody"}.
21238 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
21239 Additional plugin directories. They are searched in all the specified
21240 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
21241 Defaults to @samp{()}.
21244 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
21245 Every virtual host and component needs a certificate so that clients and
21246 servers can securely verify its identity. Prosody will automatically load
21247 certificates/keys from the directory specified here.
21248 Defaults to @samp{"/etc/prosody/certs"}.
21251 @deftypevr {@code{prosody-configuration} parameter} string-list admins
21252 This is a list of accounts that are admins for the server. Note that you
21253 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
21254 @url{https://prosody.im/doc/creating_accounts}.
21255 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
21256 Defaults to @samp{()}.
21259 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
21260 Enable use of libevent for better performance under high load. See
21261 @url{https://prosody.im/doc/libevent}.
21262 Defaults to @samp{#f}.
21265 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
21266 This is the list of modules Prosody will load on startup. It looks for
21267 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
21268 Documentation on modules can be found at:
21269 @url{https://prosody.im/doc/modules}.
21270 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
21273 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
21274 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
21275 should you want to disable them then add them to this list.
21276 Defaults to @samp{()}.
21279 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
21280 Path to a text file where the shared groups are defined. If this path is
21281 empty then @samp{mod_groups} does nothing. See
21282 @url{https://prosody.im/doc/modules/mod_groups}.
21283 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
21286 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
21287 Disable account creation by default, for security. See
21288 @url{https://prosody.im/doc/creating_accounts}.
21289 Defaults to @samp{#f}.
21292 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
21293 These are the SSL/TLS-related settings. Most of them are disabled so to
21294 use Prosody's defaults. If you do not completely understand these options, do
21295 not add them to your config, it is easy to lower the security of your server
21296 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
21298 Available @code{ssl-configuration} fields are:
21300 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
21301 This determines what handshake to use.
21304 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
21305 Path to your private key file.
21308 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
21309 Path to your certificate file.
21312 @deftypevr {@code{ssl-configuration} parameter} file-object capath
21313 Path to directory containing root certificates that you wish Prosody to
21314 trust when verifying the certificates of remote servers.
21315 Defaults to @samp{"/etc/ssl/certs"}.
21318 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
21319 Path to a file containing root certificates that you wish Prosody to trust.
21320 Similar to @code{capath} but with all certificates concatenated together.
21323 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
21324 A list of verification options (these mostly map to OpenSSL's
21325 @code{set_verify()} flags).
21328 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
21329 A list of general options relating to SSL/TLS. These map to OpenSSL's
21330 @code{set_options()}. For a full list of options available in LuaSec, see the
21334 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
21335 How long a chain of certificate authorities to check when looking for a
21336 trusted root certificate.
21339 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
21340 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
21341 clients, and in what order.
21344 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
21345 A path to a file containing parameters for Diffie-Hellman key exchange. You
21346 can create such a file with:
21347 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
21350 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
21351 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
21352 @samp{"secp384r1"}.
21355 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
21356 A list of ``extra'' verification options.
21359 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
21360 Password for encrypted private keys.
21365 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
21366 Whether to force all client-to-server connections to be encrypted or not.
21367 See @url{https://prosody.im/doc/modules/mod_tls}.
21368 Defaults to @samp{#f}.
21371 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
21372 Set of mechanisms that will never be offered. See
21373 @url{https://prosody.im/doc/modules/mod_saslauth}.
21374 Defaults to @samp{("DIGEST-MD5")}.
21377 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
21378 Whether to force all server-to-server connections to be encrypted or not.
21379 See @url{https://prosody.im/doc/modules/mod_tls}.
21380 Defaults to @samp{#f}.
21383 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
21384 Whether to require encryption and certificate authentication. This
21385 provides ideal security, but requires servers you communicate with to support
21386 encryption AND present valid, trusted certificates. See
21387 @url{https://prosody.im/doc/s2s#security}.
21388 Defaults to @samp{#f}.
21391 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
21392 Many servers don't support encryption or have invalid or self-signed
21393 certificates. You can list domains here that will not be required to
21394 authenticate using certificates. They will be authenticated using DNS. See
21395 @url{https://prosody.im/doc/s2s#security}.
21396 Defaults to @samp{()}.
21399 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
21400 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
21401 valid certificates for some domains by specifying a list here. See
21402 @url{https://prosody.im/doc/s2s#security}.
21403 Defaults to @samp{()}.
21406 @deftypevr {@code{prosody-configuration} parameter} string authentication
21407 Select the authentication backend to use. The default provider stores
21408 passwords in plaintext and uses Prosody's configured data storage to store the
21409 authentication data. If you do not trust your server please see
21410 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
21411 about using the hashed backend. See also
21412 @url{https://prosody.im/doc/authentication}
21413 Defaults to @samp{"internal_plain"}.
21416 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
21417 Set logging options. Advanced logging configuration is not yet supported
21418 by the Prosody service. See @url{https://prosody.im/doc/logging}.
21419 Defaults to @samp{"*syslog"}.
21422 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
21423 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
21424 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
21427 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
21428 Maximum allowed size of the HTTP body (in bytes).
21431 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
21432 Some modules expose their own URL in various ways. This URL is built
21433 from the protocol, host and port used. If Prosody sits behind a proxy, the
21434 public URL will be @code{http-external-url} instead. See
21435 @url{https://prosody.im/doc/http#external_url}.
21438 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
21439 A host in Prosody is a domain on which user accounts can be created. For
21440 example if you want your users to have addresses like
21441 @samp{"john.smith@@example.com"} then you need to add a host
21442 @samp{"example.com"}. All options in this list will apply only to this host.
21444 Note: the name @emph{virtual} host is used in configuration to avoid confusion with
21445 the actual physical host that Prosody is installed on. A single Prosody
21446 instance can serve many domains, each one defined as a VirtualHost entry in
21447 Prosody's configuration. Conversely a server that hosts a single domain would
21448 have just one VirtualHost entry.
21450 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
21452 Available @code{virtualhost-configuration} fields are:
21454 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:
21455 @deftypevr {@code{virtualhost-configuration} parameter} string domain
21456 Domain you wish Prosody to serve.
21461 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
21462 Components are extra services on a server which are available to clients,
21463 usually on a subdomain of the main server (such as
21464 @samp{"mycomponent.example.com"}). Example components might be chatroom
21465 servers, user directories, or gateways to other protocols.
21467 Internal components are implemented with Prosody-specific plugins. To add an
21468 internal component, you simply fill the hostname field, and the plugin you wish
21469 to use for the component.
21471 See @url{https://prosody.im/doc/components}.
21472 Defaults to @samp{()}.
21474 Available @code{int-component-configuration} fields are:
21476 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:
21477 @deftypevr {@code{int-component-configuration} parameter} string hostname
21478 Hostname of the component.
21481 @deftypevr {@code{int-component-configuration} parameter} string plugin
21482 Plugin you wish to use for the component.
21485 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
21486 Multi-user chat (MUC) is Prosody's module for allowing you to create
21487 hosted chatrooms/conferences for XMPP users.
21489 General information on setting up and using multi-user chatrooms can be found
21490 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
21491 which you should read if you are new to XMPP chatrooms.
21493 See also @url{https://prosody.im/doc/modules/mod_muc}.
21495 Available @code{mod-muc-configuration} fields are:
21497 @deftypevr {@code{mod-muc-configuration} parameter} string name
21498 The name to return in service discovery responses.
21499 Defaults to @samp{"Prosody Chatrooms"}.
21502 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
21503 If @samp{#t}, this will only allow admins to create new chatrooms.
21504 Otherwise anyone can create a room. The value @samp{"local"} restricts room
21505 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
21506 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
21507 restricts to service administrators only.
21508 Defaults to @samp{#f}.
21511 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
21512 Maximum number of history messages that will be sent to the member that has
21513 just joined the room.
21514 Defaults to @samp{20}.
21521 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
21522 External components use XEP-0114, which most standalone components
21523 support. To add an external component, you simply fill the hostname field. See
21524 @url{https://prosody.im/doc/components}.
21525 Defaults to @samp{()}.
21527 Available @code{ext-component-configuration} fields are:
21529 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:
21530 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
21531 Password which the component will use to log in.
21534 @deftypevr {@code{ext-component-configuration} parameter} string hostname
21535 Hostname of the component.
21540 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
21541 Port(s) Prosody listens on for component connections.
21542 Defaults to @samp{(5347)}.
21545 @deftypevr {@code{prosody-configuration} parameter} string component-interface
21546 Interface Prosody listens on for component connections.
21547 Defaults to @samp{"127.0.0.1"}.
21550 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
21551 Raw content that will be added to the configuration file.
21554 It could be that you just want to get a @code{prosody.cfg.lua}
21555 up and running. In that case, you can pass an
21556 @code{opaque-prosody-configuration} record as the value of
21557 @code{prosody-service-type}. As its name indicates, an opaque configuration
21558 does not have easy reflective capabilities.
21559 Available @code{opaque-prosody-configuration} fields are:
21561 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
21562 The prosody package.
21565 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
21566 The contents of the @code{prosody.cfg.lua} to use.
21569 For example, if your @code{prosody.cfg.lua} is just the empty
21570 string, you could instantiate a prosody service like this:
21573 (service prosody-service-type
21574 (opaque-prosody-configuration
21575 (prosody.cfg.lua "")))
21578 @c end of Prosody auto-generated documentation
21580 @subsubheading BitlBee Service
21582 @cindex IRC (Internet Relay Chat)
21583 @cindex IRC gateway
21584 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
21585 interface to a variety of messaging protocols such as XMPP.
21587 @defvr {Scheme Variable} bitlbee-service-type
21588 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
21589 gateway daemon. Its value is a @code{bitlbee-configuration} (see
21592 To have BitlBee listen on port 6667 on localhost, add this line to your
21596 (service bitlbee-service-type)
21600 @deftp {Data Type} bitlbee-configuration
21601 This is the configuration for BitlBee, with the following fields:
21604 @item @code{interface} (default: @code{"127.0.0.1"})
21605 @itemx @code{port} (default: @code{6667})
21606 Listen on the network interface corresponding to the IP address
21607 specified in @var{interface}, on @var{port}.
21609 When @var{interface} is @code{127.0.0.1}, only local clients can
21610 connect; when it is @code{0.0.0.0}, connections can come from any
21611 networking interface.
21613 @item @code{bitlbee} (default: @code{bitlbee})
21614 The BitlBee package to use.
21616 @item @code{plugins} (default: @code{'()})
21617 List of plugin packages to use---e.g., @code{bitlbee-discord}.
21619 @item @code{extra-settings} (default: @code{""})
21620 Configuration snippet added as-is to the BitlBee configuration file.
21624 @subsubheading Quassel Service
21626 @cindex IRC (Internet Relay Chat)
21627 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
21628 meaning that one or more clients can attach to and detach from the
21631 @defvr {Scheme Variable} quassel-service-type
21632 This is the service type for the @url{https://quassel-irc.org/,Quassel}
21633 IRC backend daemon. Its value is a @code{quassel-configuration}
21637 @deftp {Data Type} quassel-configuration
21638 This is the configuration for Quassel, with the following fields:
21641 @item @code{quassel} (default: @code{quassel})
21642 The Quassel package to use.
21644 @item @code{interface} (default: @code{"::,0.0.0.0"})
21645 @item @code{port} (default: @code{4242})
21646 Listen on the network interface(s) corresponding to the IPv4 or IPv6
21647 interfaces specified in the comma delimited @var{interface}, on
21650 @item @code{loglevel} (default: @code{"Info"})
21651 The level of logging desired. Accepted values are Debug, Info, Warning
21656 @node Telephony Services
21657 @subsection Telephony Services
21659 @cindex Murmur (VoIP server)
21660 @cindex VoIP server
21661 This section describes how to set up and run a Murmur server. Murmur is
21662 the server of the @uref{https://mumble.info, Mumble} voice-over-IP
21665 @deftp {Data Type} murmur-configuration
21666 The service type for the Murmur server. An example configuration can
21670 (service murmur-service-type
21671 (murmur-configuration
21673 "Welcome to this Mumble server running on Guix!")
21674 (cert-required? #t) ;disallow text password logins
21675 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
21676 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
21679 After reconfiguring your system, you can manually set the murmur @code{SuperUser}
21680 password with the command that is printed during the activation phase.
21682 It is recommended to register a normal Mumble user account
21683 and grant it admin or moderator rights.
21684 You can use the @code{mumble} client to
21685 login as new normal user, register yourself, and log out.
21686 For the next step login with the name @code{SuperUser} use
21687 the @code{SuperUser} password that you set previously,
21688 and grant your newly registered mumble user administrator or moderator
21689 rights and create some channels.
21691 Available @code{murmur-configuration} fields are:
21694 @item @code{package} (default: @code{mumble})
21695 Package that contains @code{bin/murmurd}.
21697 @item @code{user} (default: @code{"murmur"})
21698 User who will run the Murmur server.
21700 @item @code{group} (default: @code{"murmur"})
21701 Group of the user who will run the murmur server.
21703 @item @code{port} (default: @code{64738})
21704 Port on which the server will listen.
21706 @item @code{welcome-text} (default: @code{""})
21707 Welcome text sent to clients when they connect.
21709 @item @code{server-password} (default: @code{""})
21710 Password the clients have to enter in order to connect.
21712 @item @code{max-users} (default: @code{100})
21713 Maximum of users that can be connected to the server at once.
21715 @item @code{max-user-bandwidth} (default: @code{#f})
21716 Maximum voice traffic a user can send per second.
21718 @item @code{database-file} (default: @code{"/var/lib/murmur/db.sqlite"})
21719 File name of the sqlite database.
21720 The service's user will become the owner of the directory.
21722 @item @code{log-file} (default: @code{"/var/log/murmur/murmur.log"})
21723 File name of the log file.
21724 The service's user will become the owner of the directory.
21726 @item @code{autoban-attempts} (default: @code{10})
21727 Maximum number of logins a user can make in @code{autoban-timeframe}
21728 without getting auto banned for @code{autoban-time}.
21730 @item @code{autoban-timeframe} (default: @code{120})
21731 Timeframe for autoban in seconds.
21733 @item @code{autoban-time} (default: @code{300})
21734 Amount of time in seconds for which a client gets banned
21735 when violating the autoban limits.
21737 @item @code{opus-threshold} (default: @code{100})
21738 Percentage of clients that need to support opus
21739 before switching over to opus audio codec.
21741 @item @code{channel-nesting-limit} (default: @code{10})
21742 How deep channels can be nested at maximum.
21744 @item @code{channelname-regex} (default: @code{#f})
21745 A string in form of a Qt regular expression that channel names must conform to.
21747 @item @code{username-regex} (default: @code{#f})
21748 A string in form of a Qt regular expression that user names must conform to.
21750 @item @code{text-message-length} (default: @code{5000})
21751 Maximum size in bytes that a user can send in one text chat message.
21753 @item @code{image-message-length} (default: @code{(* 128 1024)})
21754 Maximum size in bytes that a user can send in one image message.
21756 @item @code{cert-required?} (default: @code{#f})
21757 If it is set to @code{#t} clients that use weak password authentication
21758 will not be accepted. Users must have completed the certificate wizard to join.
21760 @item @code{remember-channel?} (default: @code{#f})
21761 Should murmur remember the last channel each user was in when they disconnected
21762 and put them into the remembered channel when they rejoin.
21764 @item @code{allow-html?} (default: @code{#f})
21765 Should html be allowed in text messages, user comments, and channel descriptions.
21767 @item @code{allow-ping?} (default: @code{#f})
21768 Setting to true exposes the current user count, the maximum user count, and
21769 the server's maximum bandwidth per client to unauthenticated users. In the
21770 Mumble client, this information is shown in the Connect dialog.
21772 Disabling this setting will prevent public listing of the server.
21774 @item @code{bonjour?} (default: @code{#f})
21775 Should the server advertise itself in the local network through the bonjour protocol.
21777 @item @code{send-version?} (default: @code{#f})
21778 Should the murmur server version be exposed in ping requests.
21780 @item @code{log-days} (default: @code{31})
21781 Murmur also stores logs in the database, which are accessible via RPC.
21782 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
21783 or -1 to disable logging to the database.
21785 @item @code{obfuscate-ips?} (default: @code{#t})
21786 Should logged ips be obfuscated to protect the privacy of users.
21788 @item @code{ssl-cert} (default: @code{#f})
21789 File name of the SSL/TLS certificate used for encrypted connections.
21792 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
21794 @item @code{ssl-key} (default: @code{#f})
21795 Filepath to the ssl private key used for encrypted connections.
21797 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
21800 @item @code{ssl-dh-params} (default: @code{#f})
21801 File name of a PEM-encoded file with Diffie-Hellman parameters
21802 for the SSL/TLS encryption. Alternatively you set it to
21803 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
21804 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
21806 @item @code{ssl-ciphers} (default: @code{#f})
21807 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
21810 This option is specified using
21811 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
21812 OpenSSL cipher list notation}.
21814 It is recommended that you try your cipher string using 'openssl ciphers <string>'
21815 before setting it here, to get a feel for which cipher suites you will get.
21816 After setting this option, it is recommend that you inspect your Murmur log
21817 to ensure that Murmur is using the cipher suites that you expected it to.
21819 Note: Changing this option may impact the backwards compatibility of your
21820 Murmur server, and can remove the ability for older Mumble clients to be able
21823 @item @code{public-registration} (default: @code{#f})
21824 Must be a @code{<murmur-public-registration-configuration>} record or @code{#f}.
21826 You can optionally register your server in the public server list that the
21827 @code{mumble} client shows on startup.
21828 You cannot register your server if you have set a @code{server-password},
21829 or set @code{allow-ping} to @code{#f}.
21831 It might take a few hours until it shows up in the public list.
21833 @item @code{file} (default: @code{#f})
21834 Optional alternative override for this configuration.
21838 @deftp {Data Type} murmur-public-registration-configuration
21839 Configuration for public registration of a murmur service.
21843 This is a display name for your server. Not to be confused with the hostname.
21845 @item @code{password}
21846 A password to identify your registration.
21847 Subsequent updates will need the same password. Don't lose your password.
21850 This should be a @code{http://} or @code{https://} link to your web
21853 @item @code{hostname} (default: @code{#f})
21854 By default your server will be listed by its IP address.
21855 If it is set your server will be linked by this host name instead.
21861 @node Monitoring Services
21862 @subsection Monitoring Services
21864 @subsubheading Tailon Service
21866 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
21867 viewing and searching log files.
21869 The following example will configure the service with default values.
21870 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
21873 (service tailon-service-type)
21876 The following example customises more of the Tailon configuration,
21877 adding @command{sed} to the list of allowed commands.
21880 (service tailon-service-type
21881 (tailon-configuration
21883 (tailon-configuration-file
21884 (allowed-commands '("tail" "grep" "awk" "sed"))))))
21888 @deftp {Data Type} tailon-configuration
21889 Data type representing the configuration of Tailon.
21890 This type has the following parameters:
21893 @item @code{config-file} (default: @code{(tailon-configuration-file)})
21894 The configuration file to use for Tailon. This can be set to a
21895 @dfn{tailon-configuration-file} record value, or any gexp
21896 (@pxref{G-Expressions}).
21898 For example, to instead use a local file, the @code{local-file} function
21902 (service tailon-service-type
21903 (tailon-configuration
21904 (config-file (local-file "./my-tailon.conf"))))
21907 @item @code{package} (default: @code{tailon})
21908 The tailon package to use.
21913 @deftp {Data Type} tailon-configuration-file
21914 Data type representing the configuration options for Tailon.
21915 This type has the following parameters:
21918 @item @code{files} (default: @code{(list "/var/log")})
21919 List of files to display. The list can include strings for a single file
21920 or directory, or a list, where the first item is the name of a
21921 subsection, and the remaining items are the files or directories in that
21924 @item @code{bind} (default: @code{"localhost:8080"})
21925 Address and port to which Tailon should bind on.
21927 @item @code{relative-root} (default: @code{#f})
21928 URL path to use for Tailon, set to @code{#f} to not use a path.
21930 @item @code{allow-transfers?} (default: @code{#t})
21931 Allow downloading the log files in the web interface.
21933 @item @code{follow-names?} (default: @code{#t})
21934 Allow tailing of not-yet existent files.
21936 @item @code{tail-lines} (default: @code{200})
21937 Number of lines to read initially from each file.
21939 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
21940 Commands to allow running. By default, @code{sed} is disabled.
21942 @item @code{debug?} (default: @code{#f})
21943 Set @code{debug?} to @code{#t} to show debug messages.
21945 @item @code{wrap-lines} (default: @code{#t})
21946 Initial line wrapping state in the web interface. Set to @code{#t} to
21947 initially wrap lines (the default), or to @code{#f} to initially not
21950 @item @code{http-auth} (default: @code{#f})
21951 HTTP authentication type to use. Set to @code{#f} to disable
21952 authentication (the default). Supported values are @code{"digest"} or
21955 @item @code{users} (default: @code{#f})
21956 If HTTP authentication is enabled (see @code{http-auth}), access will be
21957 restricted to the credentials provided here. To configure users, use a
21958 list of pairs, where the first element of the pair is the username, and
21959 the 2nd element of the pair is the password.
21962 (tailon-configuration-file
21963 (http-auth "basic")
21964 (users '(("user1" . "password1")
21965 ("user2" . "password2"))))
21972 @subsubheading Darkstat Service
21974 Darkstat is a packet sniffer that captures network traffic, calculates
21975 statistics about usage, and serves reports over HTTP.
21977 @defvar {Scheme Variable} darkstat-service-type
21978 This is the service type for the
21979 @uref{https://unix4lyfe.org/darkstat/, darkstat}
21980 service, its value must be a @code{darkstat-configuration} record as in
21984 (service darkstat-service-type
21985 (darkstat-configuration
21986 (interface "eno1")))
21990 @deftp {Data Type} darkstat-configuration
21991 Data type representing the configuration of @command{darkstat}.
21994 @item @code{package} (default: @code{darkstat})
21995 The darkstat package to use.
21997 @item @code{interface}
21998 Capture traffic on the specified network interface.
22000 @item @code{port} (default: @code{"667"})
22001 Bind the web interface to the specified port.
22003 @item @code{bind-address} (default: @code{"127.0.0.1"})
22004 Bind the web interface to the specified address.
22006 @item @code{base} (default: @code{"/"})
22007 Specify the path of the base URL. This can be useful if
22008 @command{darkstat} is accessed via a reverse proxy.
22013 @subsubheading Prometheus Node Exporter Service
22015 @cindex prometheus-node-exporter
22016 The Prometheus ``node exporter'' makes hardware and operating system statistics
22017 provided by the Linux kernel available for the Prometheus monitoring system.
22018 This service should be deployed on all physical nodes and virtual machines,
22019 where monitoring these statistics is desirable.
22021 @defvar {Scheme variable} prometheus-node-exporter-service-type
22022 This is the service type for the
22023 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
22024 service, its value must be a @code{prometheus-node-exporter-configuration}.
22027 (service prometheus-node-exporter-service-type)
22031 @deftp {Data Type} prometheus-node-exporter-configuration
22032 Data type representing the configuration of @command{node_exporter}.
22035 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
22036 The prometheus-node-exporter package to use.
22038 @item @code{web-listen-address} (default: @code{":9100"})
22039 Bind the web interface to the specified address.
22041 @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
22042 This directory can be used to export metrics specific to this machine.
22043 Files containing metrics in the text format, with the filename ending in
22044 @code{.prom} should be placed in this directory.
22046 @item @code{extra-options} (default: @code{'()})
22047 Extra options to pass to the Prometheus node exporter.
22052 @subsubheading Zabbix server
22053 @cindex zabbix zabbix-server
22054 Zabbix provides monitoring metrics, among others network utilization, CPU load
22055 and disk space consumption:
22058 @item High performance, high capacity (able to monitor hundreds of thousands of devices).
22059 @item Auto-discovery of servers and network devices and interfaces.
22060 @item Low-level discovery, allows to automatically start monitoring new items, file systems or network interfaces among others.
22061 @item Distributed monitoring with centralized web administration.
22062 @item Native high performance agents.
22063 @item SLA, and ITIL KPI metrics on reporting.
22064 @item High-level (business) view of monitored resources through user-defined visual console screens and dashboards.
22065 @item Remote command execution through Zabbix proxies.
22068 @c %start of fragment
22070 Available @code{zabbix-server-configuration} fields are:
22072 @deftypevr {@code{zabbix-server-configuration} parameter} package zabbix-server
22073 The zabbix-server package.
22077 @deftypevr {@code{zabbix-server-configuration} parameter} string user
22078 User who will run the Zabbix server.
22080 Defaults to @samp{"zabbix"}.
22084 @deftypevr {@code{zabbix-server-configuration} parameter} group group
22085 Group who will run the Zabbix server.
22087 Defaults to @samp{"zabbix"}.
22091 @deftypevr {@code{zabbix-server-configuration} parameter} string db-host
22092 Database host name.
22094 Defaults to @samp{"127.0.0.1"}.
22098 @deftypevr {@code{zabbix-server-configuration} parameter} string db-name
22101 Defaults to @samp{"zabbix"}.
22105 @deftypevr {@code{zabbix-server-configuration} parameter} string db-user
22108 Defaults to @samp{"zabbix"}.
22112 @deftypevr {@code{zabbix-server-configuration} parameter} string db-password
22113 Database password. Please, use @code{include-files} with
22114 @code{DBPassword=SECRET} inside a specified file instead.
22116 Defaults to @samp{""}.
22120 @deftypevr {@code{zabbix-server-configuration} parameter} number db-port
22123 Defaults to @samp{5432}.
22127 @deftypevr {@code{zabbix-server-configuration} parameter} string log-type
22128 Specifies where log messages are written to:
22132 @code{system} - syslog.
22135 @code{file} - file specified with @code{log-file} parameter.
22138 @code{console} - standard output.
22142 Defaults to @samp{""}.
22146 @deftypevr {@code{zabbix-server-configuration} parameter} string log-file
22147 Log file name for @code{log-type} @code{file} parameter.
22149 Defaults to @samp{"/var/log/zabbix/server.log"}.
22153 @deftypevr {@code{zabbix-server-configuration} parameter} string pid-file
22156 Defaults to @samp{"/var/run/zabbix/zabbix_server.pid"}.
22160 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-ca-location
22161 The location of certificate authority (CA) files for SSL server
22162 certificate verification.
22164 Defaults to @samp{"/etc/ssl/certs/ca-certificates.crt"}.
22168 @deftypevr {@code{zabbix-server-configuration} parameter} string ssl-cert-location
22169 Location of SSL client certificates.
22171 Defaults to @samp{"/etc/ssl/certs"}.
22175 @deftypevr {@code{zabbix-server-configuration} parameter} string extra-options
22176 Extra options will be appended to Zabbix server configuration file.
22178 Defaults to @samp{""}.
22182 @deftypevr {@code{zabbix-server-configuration} parameter} include-files include-files
22183 You may include individual files or all files in a directory in the
22184 configuration file.
22186 Defaults to @samp{()}.
22190 @c %end of fragment
22192 @subsubheading Zabbix agent
22193 @cindex zabbix zabbix-agent
22195 Zabbix agent gathers information for Zabbix server.
22197 @c %start of fragment
22199 Available @code{zabbix-agent-configuration} fields are:
22201 @deftypevr {@code{zabbix-agent-configuration} parameter} package zabbix-agent
22202 The zabbix-agent package.
22206 @deftypevr {@code{zabbix-agent-configuration} parameter} string user
22207 User who will run the Zabbix agent.
22209 Defaults to @samp{"zabbix"}.
22213 @deftypevr {@code{zabbix-agent-configuration} parameter} group group
22214 Group who will run the Zabbix agent.
22216 Defaults to @samp{"zabbix"}.
22220 @deftypevr {@code{zabbix-agent-configuration} parameter} string hostname
22221 Unique, case sensitive hostname which is required for active checks and
22222 must match hostname as configured on the server.
22224 Defaults to @samp{""}.
22228 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-type
22229 Specifies where log messages are written to:
22233 @code{system} - syslog.
22236 @code{file} - file specified with @code{log-file} parameter.
22239 @code{console} - standard output.
22243 Defaults to @samp{""}.
22247 @deftypevr {@code{zabbix-agent-configuration} parameter} string log-file
22248 Log file name for @code{log-type} @code{file} parameter.
22250 Defaults to @samp{"/var/log/zabbix/agent.log"}.
22254 @deftypevr {@code{zabbix-agent-configuration} parameter} string pid-file
22257 Defaults to @samp{"/var/run/zabbix/zabbix_agent.pid"}.
22261 @deftypevr {@code{zabbix-agent-configuration} parameter} list server
22262 List of IP addresses, optionally in CIDR notation, or hostnames of
22263 Zabbix servers and Zabbix proxies. Incoming connections will be
22264 accepted only from the hosts listed here.
22266 Defaults to @samp{("127.0.0.1")}.
22270 @deftypevr {@code{zabbix-agent-configuration} parameter} list server-active
22271 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
22272 proxies for active checks. If port is not specified, default port is
22273 used. If this parameter is not specified, active checks are disabled.
22275 Defaults to @samp{("127.0.0.1")}.
22279 @deftypevr {@code{zabbix-agent-configuration} parameter} string extra-options
22280 Extra options will be appended to Zabbix server configuration file.
22282 Defaults to @samp{""}.
22286 @deftypevr {@code{zabbix-agent-configuration} parameter} include-files include-files
22287 You may include individual files or all files in a directory in the
22288 configuration file.
22290 Defaults to @samp{()}.
22294 @c %end of fragment
22296 @subsubheading Zabbix front-end
22297 @cindex zabbix zabbix-front-end
22299 This service provides a WEB interface to Zabbix server.
22301 @c %start of fragment
22303 Available @code{zabbix-front-end-configuration} fields are:
22305 @deftypevr {@code{zabbix-front-end-configuration} parameter} nginx-server-configuration-list nginx
22306 NGINX configuration.
22310 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-host
22311 Database host name.
22313 Defaults to @samp{"localhost"}.
22317 @deftypevr {@code{zabbix-front-end-configuration} parameter} number db-port
22320 Defaults to @samp{5432}.
22324 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-name
22327 Defaults to @samp{"zabbix"}.
22331 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-user
22334 Defaults to @samp{"zabbix"}.
22338 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-password
22339 Database password. Please, use @code{db-secret-file} instead.
22341 Defaults to @samp{""}.
22345 @deftypevr {@code{zabbix-front-end-configuration} parameter} string db-secret-file
22346 Secret file containing the credentials for the Zabbix front-end. The value
22347 must be a local file name, not a G-expression. You are expected to create
22348 this file manually. Its contents will be copied into @file{zabbix.conf.php}
22349 as the value of @code{$DB['PASSWORD']}.
22351 Defaults to @samp{""}.
22355 @deftypevr {@code{zabbix-front-end-configuration} parameter} string zabbix-host
22356 Zabbix server hostname.
22358 Defaults to @samp{"localhost"}.
22362 @deftypevr {@code{zabbix-front-end-configuration} parameter} number zabbix-port
22363 Zabbix server port.
22365 Defaults to @samp{10051}.
22370 @c %end of fragment
22372 @node Kerberos Services
22373 @subsection Kerberos Services
22376 The @code{(gnu services kerberos)} module provides services relating to
22377 the authentication protocol @dfn{Kerberos}.
22379 @subsubheading Krb5 Service
22381 Programs using a Kerberos client library normally
22382 expect a configuration file in @file{/etc/krb5.conf}.
22383 This service generates such a file from a definition provided in the
22384 operating system declaration.
22385 It does not cause any daemon to be started.
22387 No ``keytab'' files are provided by this service---you must explicitly create them.
22388 This service is known to work with the MIT client library, @code{mit-krb5}.
22389 Other implementations have not been tested.
22391 @defvr {Scheme Variable} krb5-service-type
22392 A service type for Kerberos 5 clients.
22396 Here is an example of its use:
22398 (service krb5-service-type
22399 (krb5-configuration
22400 (default-realm "EXAMPLE.COM")
22401 (allow-weak-crypto? #t)
22404 (name "EXAMPLE.COM")
22405 (admin-server "groucho.example.com")
22406 (kdc "karl.example.com"))
22409 (admin-server "kerb-admin.argrx.edu")
22410 (kdc "keys.argrx.edu"))))))
22414 This example provides a Kerberos@tie{}5 client configuration which:
22416 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
22417 of which have distinct administration servers and key distribution centers;
22418 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
22419 specified by clients;
22420 @item Accepts services which only support encryption types known to be weak.
22423 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
22424 Only the most commonly used ones are described here.
22425 For a full list, and more detailed explanation of each, see the MIT
22426 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
22430 @deftp {Data Type} krb5-realm
22431 @cindex realm, kerberos
22434 This field is a string identifying the name of the realm.
22435 A common convention is to use the fully qualified DNS name of your organization,
22436 converted to upper case.
22438 @item @code{admin-server}
22439 This field is a string identifying the host where the administration server is
22443 This field is a string identifying the key distribution center
22448 @deftp {Data Type} krb5-configuration
22451 @item @code{allow-weak-crypto?} (default: @code{#f})
22452 If this flag is @code{#t} then services which only offer encryption algorithms
22453 known to be weak will be accepted.
22455 @item @code{default-realm} (default: @code{#f})
22456 This field should be a string identifying the default Kerberos
22457 realm for the client.
22458 You should set this field to the name of your Kerberos realm.
22459 If this value is @code{#f}
22460 then a realm must be specified with every Kerberos principal when invoking programs
22461 such as @command{kinit}.
22463 @item @code{realms}
22464 This should be a non-empty list of @code{krb5-realm} objects, which clients may
22466 Normally, one of them will have a @code{name} field matching the @code{default-realm}
22472 @subsubheading PAM krb5 Service
22475 The @code{pam-krb5} service allows for login authentication and password
22476 management via Kerberos.
22477 You will need this service if you want PAM enabled applications to authenticate
22478 users using Kerberos.
22480 @defvr {Scheme Variable} pam-krb5-service-type
22481 A service type for the Kerberos 5 PAM module.
22484 @deftp {Data Type} pam-krb5-configuration
22485 Data type representing the configuration of the Kerberos 5 PAM module.
22486 This type has the following parameters:
22488 @item @code{pam-krb5} (default: @code{pam-krb5})
22489 The pam-krb5 package to use.
22491 @item @code{minimum-uid} (default: @code{1000})
22492 The smallest user ID for which Kerberos authentications should be attempted.
22493 Local accounts with lower values will silently fail to authenticate.
22498 @node LDAP Services
22499 @subsection LDAP Services
22501 @cindex nslcd, LDAP service
22503 The @code{(gnu services authentication)} module provides the
22504 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
22505 server. In addition to configuring the service itself, you may want to add
22506 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
22507 Switch} for detailed information.
22509 Here is a simple operating system declaration with a default configuration of
22510 the @code{nslcd-service-type} and a Name Service Switch configuration that
22511 consults the @code{ldap} name service last:
22514 (use-service-modules authentication)
22515 (use-modules (gnu system nss))
22521 (service nslcd-service-type)
22522 (service dhcp-client-service-type)
22524 (name-service-switch
22525 (let ((services (list (name-service (name "db"))
22526 (name-service (name "files"))
22527 (name-service (name "ldap")))))
22528 (name-service-switch
22529 (inherit %mdns-host-lookup-nss)
22530 (password services)
22533 (netgroup services)
22534 (gshadow services)))))
22537 @c %start of generated documentation for nslcd-configuration
22539 Available @code{nslcd-configuration} fields are:
22541 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
22542 The @code{nss-pam-ldapd} package to use.
22546 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
22547 The number of threads to start that can handle requests and perform LDAP
22548 queries. Each thread opens a separate connection to the LDAP server.
22549 The default is to start 5 threads.
22551 Defaults to @samp{disabled}.
22555 @deftypevr {@code{nslcd-configuration} parameter} string uid
22556 This specifies the user id with which the daemon should be run.
22558 Defaults to @samp{"nslcd"}.
22562 @deftypevr {@code{nslcd-configuration} parameter} string gid
22563 This specifies the group id with which the daemon should be run.
22565 Defaults to @samp{"nslcd"}.
22569 @deftypevr {@code{nslcd-configuration} parameter} log-option log
22570 This option controls the way logging is done via a list containing
22571 SCHEME and LEVEL. The SCHEME argument may either be the symbols
22572 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
22573 argument is optional and specifies the log level. The log level may be
22574 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
22575 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
22576 specified log level or higher are logged.
22578 Defaults to @samp{("/var/log/nslcd" info)}.
22582 @deftypevr {@code{nslcd-configuration} parameter} list uri
22583 The list of LDAP server URIs. Normally, only the first server will be
22584 used with the following servers as fall-back.
22586 Defaults to @samp{("ldap://localhost:389/")}.
22590 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
22591 The version of the LDAP protocol to use. The default is to use the
22592 maximum version supported by the LDAP library.
22594 Defaults to @samp{disabled}.
22598 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
22599 Specifies the distinguished name with which to bind to the directory
22600 server for lookups. The default is to bind anonymously.
22602 Defaults to @samp{disabled}.
22606 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
22607 Specifies the credentials with which to bind. This option is only
22608 applicable when used with binddn.
22610 Defaults to @samp{disabled}.
22614 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
22615 Specifies the distinguished name to use when the root user tries to
22616 modify a user's password using the PAM module.
22618 Defaults to @samp{disabled}.
22622 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
22623 Specifies the credentials with which to bind if the root user tries to
22624 change a user's password. This option is only applicable when used with
22627 Defaults to @samp{disabled}.
22631 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
22632 Specifies the SASL mechanism to be used when performing SASL
22635 Defaults to @samp{disabled}.
22639 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
22640 Specifies the SASL realm to be used when performing SASL authentication.
22642 Defaults to @samp{disabled}.
22646 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
22647 Specifies the authentication identity to be used when performing SASL
22650 Defaults to @samp{disabled}.
22654 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
22655 Specifies the authorization identity to be used when performing SASL
22658 Defaults to @samp{disabled}.
22662 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
22663 Determines whether the LDAP server host name should be canonicalised. If
22664 this is enabled the LDAP library will do a reverse host name lookup. By
22665 default, it is left up to the LDAP library whether this check is
22668 Defaults to @samp{disabled}.
22672 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
22673 Set the name for the GSS-API Kerberos credentials cache.
22675 Defaults to @samp{disabled}.
22679 @deftypevr {@code{nslcd-configuration} parameter} string base
22680 The directory search base.
22682 Defaults to @samp{"dc=example,dc=com"}.
22686 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
22687 Specifies the search scope (subtree, onelevel, base or children). The
22688 default scope is subtree; base scope is almost never useful for name
22689 service lookups; children scope is not supported on all servers.
22691 Defaults to @samp{(subtree)}.
22695 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
22696 Specifies the policy for dereferencing aliases. The default policy is
22697 to never dereference aliases.
22699 Defaults to @samp{disabled}.
22703 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
22704 Specifies whether automatic referral chasing should be enabled. The
22705 default behaviour is to chase referrals.
22707 Defaults to @samp{disabled}.
22711 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
22712 This option allows for custom attributes to be looked up instead of the
22713 default RFC 2307 attributes. It is a list of maps, each consisting of
22714 the name of a map, the RFC 2307 attribute to match and the query
22715 expression for the attribute as it is available in the directory.
22717 Defaults to @samp{()}.
22721 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
22722 A list of filters consisting of the name of a map to which the filter
22723 applies and an LDAP search filter expression.
22725 Defaults to @samp{()}.
22729 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
22730 Specifies the time limit in seconds to use when connecting to the
22731 directory server. The default value is 10 seconds.
22733 Defaults to @samp{disabled}.
22737 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
22738 Specifies the time limit (in seconds) to wait for a response from the
22739 LDAP server. A value of zero, which is the default, is to wait
22740 indefinitely for searches to be completed.
22742 Defaults to @samp{disabled}.
22746 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
22747 Specifies the period if inactivity (in seconds) after which the con‐
22748 nection to the LDAP server will be closed. The default is not to time
22751 Defaults to @samp{disabled}.
22755 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
22756 Specifies the number of seconds to sleep when connecting to all LDAP
22757 servers fails. By default one second is waited between the first
22758 failure and the first retry.
22760 Defaults to @samp{disabled}.
22764 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
22765 Specifies the time after which the LDAP server is considered to be
22766 permanently unavailable. Once this time is reached retries will be done
22767 only once per this time period. The default value is 10 seconds.
22769 Defaults to @samp{disabled}.
22773 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
22774 Specifies whether to use SSL/TLS or not (the default is not to). If
22775 'start-tls is specified then StartTLS is used rather than raw LDAP over
22778 Defaults to @samp{disabled}.
22782 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
22783 Specifies what checks to perform on a server-supplied certificate. The
22784 meaning of the values is described in the ldap.conf(5) manual page.
22786 Defaults to @samp{disabled}.
22790 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
22791 Specifies the directory containing X.509 certificates for peer authen‐
22792 tication. This parameter is ignored when using GnuTLS.
22794 Defaults to @samp{disabled}.
22798 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
22799 Specifies the path to the X.509 certificate for peer authentication.
22801 Defaults to @samp{disabled}.
22805 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
22806 Specifies the path to an entropy source. This parameter is ignored when
22809 Defaults to @samp{disabled}.
22813 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
22814 Specifies the ciphers to use for TLS as a string.
22816 Defaults to @samp{disabled}.
22820 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
22821 Specifies the path to the file containing the local certificate for
22822 client TLS authentication.
22824 Defaults to @samp{disabled}.
22828 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
22829 Specifies the path to the file containing the private key for client TLS
22832 Defaults to @samp{disabled}.
22836 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
22837 Set this to a number greater than 0 to request paged results from the
22838 LDAP server in accordance with RFC2696. The default (0) is to not
22839 request paged results.
22841 Defaults to @samp{disabled}.
22845 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
22846 This option prevents group membership lookups through LDAP for the
22847 specified users. Alternatively, the value 'all-local may be used. With
22848 that value nslcd builds a full list of non-LDAP users on startup.
22850 Defaults to @samp{disabled}.
22854 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
22855 This option ensures that LDAP users with a numeric user id lower than
22856 the specified value are ignored.
22858 Defaults to @samp{disabled}.
22862 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
22863 This option specifies an offset that is added to all LDAP numeric user
22864 ids. This can be used to avoid user id collisions with local users.
22866 Defaults to @samp{disabled}.
22870 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
22871 This option specifies an offset that is added to all LDAP numeric group
22872 ids. This can be used to avoid user id collisions with local groups.
22874 Defaults to @samp{disabled}.
22878 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
22879 If this option is set, the member attribute of a group may point to
22880 another group. Members of nested groups are also returned in the higher
22881 level group and parent groups are returned when finding groups for a
22882 specific user. The default is not to perform extra searches for nested
22885 Defaults to @samp{disabled}.
22889 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
22890 If this option is set, the group member list is not retrieved when
22891 looking up groups. Lookups for finding which groups a user belongs to
22892 will remain functional so the user will likely still get the correct
22893 groups assigned on login.
22895 Defaults to @samp{disabled}.
22899 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
22900 If this option is set, functions which cause all user/group entries to
22901 be loaded from the directory will not succeed in doing so. This can
22902 dramatically reduce LDAP server load in situations where there are a
22903 great number of users and/or groups. This option is not recommended for
22904 most configurations.
22906 Defaults to @samp{disabled}.
22910 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
22911 This option can be used to specify how user and group names are verified
22912 within the system. This pattern is used to check all user and group
22913 names that are requested and returned from LDAP.
22915 Defaults to @samp{disabled}.
22919 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
22920 This specifies whether or not to perform searches using case-insensitive
22921 matching. Enabling this could open up the system to authorization
22922 bypass vulnerabilities and introduce nscd cache poisoning
22923 vulnerabilities which allow denial of service.
22925 Defaults to @samp{disabled}.
22929 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
22930 This option specifies whether password policy controls are requested and
22931 handled from the LDAP server when performing user authentication.
22933 Defaults to @samp{disabled}.
22937 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
22938 By default nslcd performs an LDAP search with the user's credentials
22939 after BIND (authentication) to ensure that the BIND operation was
22940 successful. The default search is a simple check to see if the user's
22941 DN exists. A search filter can be specified that will be used instead.
22942 It should return at least one entry.
22944 Defaults to @samp{disabled}.
22948 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
22949 This option allows flexible fine tuning of the authorisation check that
22950 should be performed. The search filter specified is executed and if any
22951 entries match, access is granted, otherwise access is denied.
22953 Defaults to @samp{disabled}.
22957 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
22958 If this option is set password modification using pam_ldap will be
22959 denied and the specified message will be presented to the user instead.
22960 The message can be used to direct the user to an alternative means of
22961 changing their password.
22963 Defaults to @samp{disabled}.
22967 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
22968 List of pam service names for which LDAP authentication should suffice.
22970 Defaults to @samp{()}.
22974 @c %end of generated documentation for nslcd-configuration
22978 @subsection Web Services
22983 The @code{(gnu services web)} module provides the Apache HTTP Server,
22984 the nginx web server, and also a fastcgi wrapper daemon.
22986 @subsubheading Apache HTTP Server
22988 @deffn {Scheme Variable} httpd-service-type
22989 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
22990 (@dfn{httpd}). The value for this service type is a
22991 @code{httpd-configuration} record.
22993 A simple example configuration is given below.
22996 (service httpd-service-type
22997 (httpd-configuration
23000 (server-name "www.example.com")
23001 (document-root "/srv/http/www.example.com")))))
23004 Other services can also extend the @code{httpd-service-type} to add to
23008 (simple-service 'www.example.com-server httpd-service-type
23012 (list (string-join '("ServerName www.example.com"
23013 "DocumentRoot /srv/http/www.example.com")
23018 The details for the @code{httpd-configuration}, @code{httpd-module},
23019 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
23022 @deffn {Data Type} httpd-configuration
23023 This data type represents the configuration for the httpd service.
23026 @item @code{package} (default: @code{httpd})
23027 The httpd package to use.
23029 @item @code{pid-file} (default: @code{"/var/run/httpd"})
23030 The pid file used by the shepherd-service.
23032 @item @code{config} (default: @code{(httpd-config-file)})
23033 The configuration file to use with the httpd service. The default value
23034 is a @code{httpd-config-file} record, but this can also be a different
23035 G-expression that generates a file, for example a @code{plain-file}. A
23036 file outside of the store can also be specified through a string.
23041 @deffn {Data Type} httpd-module
23042 This data type represents a module for the httpd service.
23046 The name of the module.
23049 The file for the module. This can be relative to the httpd package being
23050 used, the absolute location of a file, or a G-expression for a file
23051 within the store, for example @code{(file-append mod-wsgi
23052 "/modules/mod_wsgi.so")}.
23057 @defvr {Scheme Variable} %default-httpd-modules
23058 A default list of @code{httpd-module} objects.
23061 @deffn {Data Type} httpd-config-file
23062 This data type represents a configuration file for the httpd service.
23065 @item @code{modules} (default: @code{%default-httpd-modules})
23066 The modules to load. Additional modules can be added here, or loaded by
23067 additional configuration.
23069 For example, in order to handle requests for PHP files, you can use Apache’s
23070 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
23073 (service httpd-service-type
23074 (httpd-configuration
23079 (name "proxy_module")
23080 (file "modules/mod_proxy.so"))
23082 (name "proxy_fcgi_module")
23083 (file "modules/mod_proxy_fcgi.so"))
23084 %default-httpd-modules))
23085 (extra-config (list "\
23086 <FilesMatch \\.php$>
23087 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
23088 </FilesMatch>"))))))
23089 (service php-fpm-service-type
23090 (php-fpm-configuration
23091 (socket "/var/run/php-fpm.sock")
23092 (socket-group "httpd")))
23095 @item @code{server-root} (default: @code{httpd})
23096 The @code{ServerRoot} in the configuration file, defaults to the httpd
23097 package. Directives including @code{Include} and @code{LoadModule} are
23098 taken as relative to the server root.
23100 @item @code{server-name} (default: @code{#f})
23101 The @code{ServerName} in the configuration file, used to specify the
23102 request scheme, hostname and port that the server uses to identify
23105 This doesn't need to be set in the server config, and can be specified
23106 in virtual hosts. The default is @code{#f} to not specify a
23109 @item @code{document-root} (default: @code{"/srv/http"})
23110 The @code{DocumentRoot} from which files will be served.
23112 @item @code{listen} (default: @code{'("80")})
23113 The list of values for the @code{Listen} directives in the config
23114 file. The value should be a list of strings, when each string can
23115 specify the port number to listen on, and optionally the IP address and
23118 @item @code{pid-file} (default: @code{"/var/run/httpd"})
23119 The @code{PidFile} to use. This should match the @code{pid-file} set in
23120 the @code{httpd-configuration} so that the Shepherd service is
23121 configured correctly.
23123 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
23124 The @code{ErrorLog} to which the server will log errors.
23126 @item @code{user} (default: @code{"httpd"})
23127 The @code{User} which the server will answer requests as.
23129 @item @code{group} (default: @code{"httpd"})
23130 The @code{Group} which the server will answer requests as.
23132 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
23133 A flat list of strings and G-expressions which will be added to the end
23134 of the configuration file.
23136 Any values which the service is extended with will be appended to this
23142 @deffn {Data Type} httpd-virtualhost
23143 This data type represents a virtualhost configuration block for the httpd service.
23145 These should be added to the extra-config for the httpd-service.
23148 (simple-service 'www.example.com-server httpd-service-type
23152 (list (string-join '("ServerName www.example.com"
23153 "DocumentRoot /srv/http/www.example.com")
23158 @item @code{addresses-and-ports}
23159 The addresses and ports for the @code{VirtualHost} directive.
23161 @item @code{contents}
23162 The contents of the @code{VirtualHost} directive, this should be a list
23163 of strings and G-expressions.
23168 @subsubheading NGINX
23170 @deffn {Scheme Variable} nginx-service-type
23171 Service type for the @uref{https://nginx.org/,NGinx} web server. The
23172 value for this service type is a @code{<nginx-configuration>} record.
23174 A simple example configuration is given below.
23177 (service nginx-service-type
23178 (nginx-configuration
23180 (list (nginx-server-configuration
23181 (server-name '("www.example.com"))
23182 (root "/srv/http/www.example.com"))))))
23185 In addition to adding server blocks to the service configuration
23186 directly, this service can be extended by other services to add server
23187 blocks, as in this example:
23190 (simple-service 'my-extra-server nginx-service-type
23191 (list (nginx-server-configuration
23192 (root "/srv/http/extra-website")
23193 (try-files (list "$uri" "$uri/index.html")))))
23197 At startup, @command{nginx} has not yet read its configuration file, so
23198 it uses a default file to log error messages. If it fails to load its
23199 configuration file, that is where error messages are logged. After the
23200 configuration file is loaded, the default error log file changes as per
23201 configuration. In our case, startup error messages can be found in
23202 @file{/var/run/nginx/logs/error.log}, and after configuration in
23203 @file{/var/log/nginx/error.log}. The second location can be changed
23204 with the @var{log-directory} configuration option.
23206 @deffn {Data Type} nginx-configuration
23207 This data type represents the configuration for NGinx. Some
23208 configuration can be done through this and the other provided record
23209 types, or alternatively, a config file can be provided.
23212 @item @code{nginx} (default: @code{nginx})
23213 The nginx package to use.
23215 @item @code{log-directory} (default: @code{"/var/log/nginx"})
23216 The directory to which NGinx will write log files.
23218 @item @code{run-directory} (default: @code{"/var/run/nginx"})
23219 The directory in which NGinx will create a pid file, and write temporary
23222 @item @code{server-blocks} (default: @code{'()})
23223 A list of @dfn{server blocks} to create in the generated configuration
23224 file, the elements should be of type
23225 @code{<nginx-server-configuration>}.
23227 The following example would setup NGinx to serve @code{www.example.com}
23228 from the @code{/srv/http/www.example.com} directory, without using
23231 (service nginx-service-type
23232 (nginx-configuration
23234 (list (nginx-server-configuration
23235 (server-name '("www.example.com"))
23236 (root "/srv/http/www.example.com"))))))
23239 @item @code{upstream-blocks} (default: @code{'()})
23240 A list of @dfn{upstream blocks} to create in the generated configuration
23241 file, the elements should be of type
23242 @code{<nginx-upstream-configuration>}.
23244 Configuring upstreams through the @code{upstream-blocks} can be useful
23245 when combined with @code{locations} in the
23246 @code{<nginx-server-configuration>} records. The following example
23247 creates a server configuration with one location configuration, that
23248 will proxy requests to a upstream configuration, which will handle
23249 requests with two servers.
23254 (nginx-configuration
23256 (list (nginx-server-configuration
23257 (server-name '("www.example.com"))
23258 (root "/srv/http/www.example.com")
23261 (nginx-location-configuration
23263 (body '("proxy_pass http://server-proxy;"))))))))
23265 (list (nginx-upstream-configuration
23266 (name "server-proxy")
23267 (servers (list "server1.example.com"
23268 "server2.example.com")))))))
23271 @item @code{file} (default: @code{#f})
23272 If a configuration @var{file} is provided, this will be used, rather than
23273 generating a configuration file from the provided @code{log-directory},
23274 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
23275 proper operation, these arguments should match what is in @var{file} to ensure
23276 that the directories are created when the service is activated.
23278 This can be useful if you have an existing configuration file, or it's
23279 not possible to do what is required through the other parts of the
23280 nginx-configuration record.
23282 @item @code{server-names-hash-bucket-size} (default: @code{#f})
23283 Bucket size for the server names hash tables, defaults to @code{#f} to
23284 use the size of the processors cache line.
23286 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
23287 Maximum bucket size for the server names hash tables.
23289 @item @code{modules} (default: @code{'()})
23290 List of nginx dynamic modules to load. This should be a list of file
23291 names of loadable modules, as in this example:
23296 (file-append nginx-accept-language-module "\
23297 /etc/nginx/modules/ngx_http_accept_language_module.so")
23298 (file-append nginx-lua-module "\
23299 /etc/nginx/modules/ngx_http_lua_module.so")))
23302 @item @code{lua-package-path} (default: @code{'()})
23303 List of nginx lua packages to load. This should be a list of package
23304 names of loadable lua modules, as in this example:
23307 (lua-package-path (list lua-resty-core
23314 @item @code{lua-package-cpath} (default: @code{'()})
23315 List of nginx lua C packages to load. This should be a list of package
23316 names of loadable lua C modules, as in this example:
23319 (lua-package-cpath (list lua-resty-signal))
23322 @item @code{global-directives} (default: @code{'((events . ()))})
23323 Association list of global directives for the top level of the nginx
23324 configuration. Values may themselves be association lists.
23328 `((worker_processes . 16)
23330 (events . ((worker_connections . 1024)))))
23333 @item @code{extra-content} (default: @code{""})
23334 Extra content for the @code{http} block. Should be string or a string
23335 valued G-expression.
23340 @deftp {Data Type} nginx-server-configuration
23341 Data type representing the configuration of an nginx server block.
23342 This type has the following parameters:
23345 @item @code{listen} (default: @code{'("80" "443 ssl")})
23346 Each @code{listen} directive sets the address and port for IP, or the
23347 path for a UNIX-domain socket on which the server will accept requests.
23348 Both address and port, or only address or only port can be specified.
23349 An address may also be a hostname, for example:
23352 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
23355 @item @code{server-name} (default: @code{(list 'default)})
23356 A list of server names this server represents. @code{'default} represents the
23357 default server for connections matching no other server.
23359 @item @code{root} (default: @code{"/srv/http"})
23360 Root of the website nginx will serve.
23362 @item @code{locations} (default: @code{'()})
23363 A list of @dfn{nginx-location-configuration} or
23364 @dfn{nginx-named-location-configuration} records to use within this
23367 @item @code{index} (default: @code{(list "index.html")})
23368 Index files to look for when clients ask for a directory. If it cannot be found,
23369 Nginx will send the list of files in the directory.
23371 @item @code{try-files} (default: @code{'()})
23372 A list of files whose existence is checked in the specified order.
23373 @code{nginx} will use the first file it finds to process the request.
23375 @item @code{ssl-certificate} (default: @code{#f})
23376 Where to find the certificate for secure connections. Set it to @code{#f} if
23377 you don't have a certificate or you don't want to use HTTPS.
23379 @item @code{ssl-certificate-key} (default: @code{#f})
23380 Where to find the private key for secure connections. Set it to @code{#f} if
23381 you don't have a key or you don't want to use HTTPS.
23383 @item @code{server-tokens?} (default: @code{#f})
23384 Whether the server should add its configuration to response.
23386 @item @code{raw-content} (default: @code{'()})
23387 A list of raw lines added to the server block.
23392 @deftp {Data Type} nginx-upstream-configuration
23393 Data type representing the configuration of an nginx @code{upstream}
23394 block. This type has the following parameters:
23398 Name for this group of servers.
23400 @item @code{servers}
23401 Specify the addresses of the servers in the group. The address can be
23402 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
23403 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
23404 prefix @samp{unix:}. For addresses using an IP address or domain name,
23405 the default port is 80, and a different port can be specified
23411 @deftp {Data Type} nginx-location-configuration
23412 Data type representing the configuration of an nginx @code{location}
23413 block. This type has the following parameters:
23417 URI which this location block matches.
23419 @anchor{nginx-location-configuration body}
23421 Body of the location block, specified as a list of strings. This can contain
23423 configuration directives. For example, to pass requests to a upstream
23424 server group defined using an @code{nginx-upstream-configuration} block,
23425 the following directive would be specified in the body @samp{(list "proxy_pass
23426 http://upstream-name;")}.
23431 @deftp {Data Type} nginx-named-location-configuration
23432 Data type representing the configuration of an nginx named location
23433 block. Named location blocks are used for request redirection, and not
23434 used for regular request processing. This type has the following
23439 Name to identify this location block.
23442 @xref{nginx-location-configuration body}, as the body for named location
23443 blocks can be used in a similar way to the
23444 @code{nginx-location-configuration body}. One restriction is that the
23445 body of a named location block cannot contain location blocks.
23450 @subsubheading Varnish Cache
23452 Varnish is a fast cache server that sits in between web applications
23453 and end users. It proxies requests from clients and caches the
23454 accessed URLs such that multiple requests for the same resource only
23455 creates one request to the back-end.
23457 @defvr {Scheme Variable} varnish-service-type
23458 Service type for the Varnish daemon.
23461 @deftp {Data Type} varnish-configuration
23462 Data type representing the @code{varnish} service configuration.
23463 This type has the following parameters:
23466 @item @code{package} (default: @code{varnish})
23467 The Varnish package to use.
23469 @item @code{name} (default: @code{"default"})
23470 A name for this Varnish instance. Varnish will create a directory in
23471 @file{/var/varnish/} with this name and keep temporary files there. If
23472 the name starts with a forward slash, it is interpreted as an absolute
23475 Pass the @code{-n} argument to other Varnish programs to connect to the
23476 named instance, e.g.@: @command{varnishncsa -n default}.
23478 @item @code{backend} (default: @code{"localhost:8080"})
23479 The backend to use. This option has no effect if @code{vcl} is set.
23481 @item @code{vcl} (default: #f)
23482 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
23483 is @code{#f}, Varnish will proxy @code{backend} using the default
23484 configuration. Otherwise this must be a file-like object with valid
23487 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
23488 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
23489 can do something along these lines:
23492 (define %gnu-mirror
23493 (plain-file "gnu.vcl"
23495 backend gnu @{ .host = \"www.gnu.org\"; @}"))
23499 (services (cons (service varnish-service-type
23500 (varnish-configuration
23502 (vcl %gnu-mirror)))
23506 The configuration of an already running Varnish instance can be inspected
23507 and changed using the @command{varnishadm} program.
23509 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
23510 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
23511 comprehensive documentation on Varnish and its configuration language.
23513 @item @code{listen} (default: @code{'("localhost:80")})
23514 List of addresses Varnish will listen on.
23516 @item @code{storage} (default: @code{'("malloc,128m")})
23517 List of storage backends that will be available in VCL.
23519 @item @code{parameters} (default: @code{'()})
23520 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
23522 @item @code{extra-options} (default: @code{'()})
23523 Additional arguments to pass to the @command{varnishd} process.
23528 @subsubheading Patchwork
23530 Patchwork is a patch tracking system. It can collect patches sent to a
23531 mailing list, and display them in a web interface.
23533 @defvr {Scheme Variable} patchwork-service-type
23534 Service type for Patchwork.
23537 The following example is an example of a minimal service for Patchwork, for
23538 the @code{patchwork.example.com} domain.
23541 (service patchwork-service-type
23542 (patchwork-configuration
23543 (domain "patchwork.example.com")
23545 (patchwork-settings-module
23546 (allowed-hosts (list domain))
23547 (default-from-email "patchwork@@patchwork.example.com")))
23548 (getmail-retriever-config
23549 (getmail-retriever-configuration
23550 (type "SimpleIMAPSSLRetriever")
23551 (server "imap.example.com")
23553 (username "patchwork")
23555 (list (file-append coreutils "/bin/cat")
23556 "/etc/getmail-patchwork-imap-password"))
23558 '((mailboxes . ("Patches"))))))))
23562 There are three records for configuring the Patchwork service. The
23563 @code{<patchwork-configuration>} relates to the configuration for Patchwork
23564 within the HTTPD service.
23566 The @code{settings-module} field within the @code{<patchwork-configuration>}
23567 record can be populated with the @code{<patchwork-settings-module>} record,
23568 which describes a settings module that is generated within the Guix store.
23570 For the @code{database-configuration} field within the
23571 @code{<patchwork-settings-module>}, the
23572 @code{<patchwork-database-configuration>} must be used.
23574 @deftp {Data Type} patchwork-configuration
23575 Data type representing the Patchwork service configuration. This type has the
23576 following parameters:
23579 @item @code{patchwork} (default: @code{patchwork})
23580 The Patchwork package to use.
23582 @item @code{domain}
23583 The domain to use for Patchwork, this is used in the HTTPD service virtual
23586 @item @code{settings-module}
23587 The settings module to use for Patchwork. As a Django application, Patchwork
23588 is configured with a Python module containing the settings. This can either be
23589 an instance of the @code{<patchwork-settings-module>} record, any other record
23590 that represents the settings in the store, or a directory outside of the
23593 @item @code{static-path} (default: @code{"/static/"})
23594 The path under which the HTTPD service should serve the static files.
23596 @item @code{getmail-retriever-config}
23597 The getmail-retriever-configuration record value to use with
23598 Patchwork. Getmail will be configured with this value, the messages will be
23599 delivered to Patchwork.
23604 @deftp {Data Type} patchwork-settings-module
23605 Data type representing a settings module for Patchwork. Some of these
23606 settings relate directly to Patchwork, but others relate to Django, the web
23607 framework used by Patchwork, or the Django Rest Framework library. This type
23608 has the following parameters:
23611 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
23612 The database connection settings used for Patchwork. See the
23613 @code{<patchwork-database-configuration>} record type for more information.
23615 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
23616 Patchwork, as a Django web application uses a secret key for cryptographically
23617 signing values. This file should contain a unique unpredictable value.
23619 If this file does not exist, it will be created and populated with a random
23620 value by the patchwork-setup shepherd service.
23622 This setting relates to Django.
23624 @item @code{allowed-hosts}
23625 A list of valid hosts for this Patchwork service. This should at least include
23626 the domain specified in the @code{<patchwork-configuration>} record.
23628 This is a Django setting.
23630 @item @code{default-from-email}
23631 The email address from which Patchwork should send email by default.
23633 This is a Patchwork setting.
23635 @item @code{static-url} (default: @code{#f})
23636 The URL to use when serving static assets. It can be part of a URL, or a full
23637 URL, but must end in a @code{/}.
23639 If the default value is used, the @code{static-path} value from the
23640 @code{<patchwork-configuration>} record will be used.
23642 This is a Django setting.
23644 @item @code{admins} (default: @code{'()})
23645 Email addresses to send the details of errors that occur. Each value should
23646 be a list containing two elements, the name and then the email address.
23648 This is a Django setting.
23650 @item @code{debug?} (default: @code{#f})
23651 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
23652 messages will be shown.
23654 This is a Django setting.
23656 @item @code{enable-rest-api?} (default: @code{#t})
23657 Whether to enable the Patchwork REST API.
23659 This is a Patchwork setting.
23661 @item @code{enable-xmlrpc?} (default: @code{#t})
23662 Whether to enable the XML RPC API.
23664 This is a Patchwork setting.
23666 @item @code{force-https-links?} (default: @code{#t})
23667 Whether to use HTTPS links on Patchwork pages.
23669 This is a Patchwork setting.
23671 @item @code{extra-settings} (default: @code{""})
23672 Extra code to place at the end of the Patchwork settings module.
23677 @deftp {Data Type} patchwork-database-configuration
23678 Data type representing the database configuration for Patchwork.
23681 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
23682 The database engine to use.
23684 @item @code{name} (default: @code{"patchwork"})
23685 The name of the database to use.
23687 @item @code{user} (default: @code{"httpd"})
23688 The user to connect to the database as.
23690 @item @code{password} (default: @code{""})
23691 The password to use when connecting to the database.
23693 @item @code{host} (default: @code{""})
23694 The host to make the database connection to.
23696 @item @code{port} (default: @code{""})
23697 The port on which to connect to the database.
23702 @subsubheading Mumi
23704 @cindex Mumi, Debbugs Web interface
23705 @cindex Debbugs, Mumi Web interface
23706 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
23707 Web interface to the Debbugs bug tracker, by default for
23708 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
23709 but it also fetches and indexes mail retrieved from Debbugs.
23711 @defvr {Scheme Variable} mumi-service-type
23712 This is the service type for Mumi.
23715 @deftp {Data Type} mumi-configuration
23716 Data type representing the Mumi service configuration. This type has the
23720 @item @code{mumi} (default: @code{mumi})
23721 The Mumi package to use.
23723 @item @code{mailer?} (default: @code{#true})
23724 Whether to enable or disable the mailer component.
23726 @item @code{mumi-configuration-sender}
23727 The email address used as the sender for comments.
23729 @item @code{mumi-configuration-smtp}
23730 A URI to configure the SMTP settings for Mailutils. This could be
23731 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
23732 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
23733 mailutils, GNU@tie{}Mailutils}.
23739 @subsubheading FastCGI
23742 FastCGI is an interface between the front-end and the back-end of a web
23743 service. It is a somewhat legacy facility; new web services should
23744 generally just talk HTTP between the front-end and the back-end.
23745 However there are a number of back-end services such as PHP or the
23746 optimized HTTP Git repository access that use FastCGI, so we have
23747 support for it in Guix.
23749 To use FastCGI, you configure the front-end web server (e.g., nginx) to
23750 dispatch some subset of its requests to the fastcgi backend, which
23751 listens on a local TCP or UNIX socket. There is an intermediary
23752 @code{fcgiwrap} program that sits between the actual backend process and
23753 the web server. The front-end indicates which backend program to run,
23754 passing that information to the @code{fcgiwrap} process.
23756 @defvr {Scheme Variable} fcgiwrap-service-type
23757 A service type for the @code{fcgiwrap} FastCGI proxy.
23760 @deftp {Data Type} fcgiwrap-configuration
23761 Data type representing the configuration of the @code{fcgiwrap} service.
23762 This type has the following parameters:
23764 @item @code{package} (default: @code{fcgiwrap})
23765 The fcgiwrap package to use.
23767 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
23768 The socket on which the @code{fcgiwrap} process should listen, as a
23769 string. Valid @var{socket} values include
23770 @code{unix:@var{/path/to/unix/socket}},
23771 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
23772 @code{tcp6:[@var{ipv6_addr}]:port}.
23774 @item @code{user} (default: @code{fcgiwrap})
23775 @itemx @code{group} (default: @code{fcgiwrap})
23776 The user and group names, as strings, under which to run the
23777 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
23778 the user asks for the specific user or group names @code{fcgiwrap} that
23779 the corresponding user and/or group is present on the system.
23781 It is possible to configure a FastCGI-backed web service to pass HTTP
23782 authentication information from the front-end to the back-end, and to
23783 allow @code{fcgiwrap} to run the back-end process as a corresponding
23784 local user. To enable this capability on the back-end, run
23785 @code{fcgiwrap} as the @code{root} user and group. Note that this
23786 capability also has to be configured on the front-end as well.
23791 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
23792 with some additional features useful for sites of any size.
23794 These features include:
23796 @item Adaptive process spawning
23797 @item Basic statistics (similar to Apache's mod_status)
23798 @item Advanced process management with graceful stop/start
23799 @item Ability to start workers with different uid/gid/chroot/environment
23800 and different php.ini (replaces safe_mode)
23801 @item Stdout & stderr logging
23802 @item Emergency restart in case of accidental opcode cache destruction
23803 @item Accelerated upload support
23804 @item Support for a "slowlog"
23805 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
23806 a special function to finish request & flush all data while continuing to do
23807 something time-consuming (video converting, stats processing, etc.)
23809 ...@: and much more.
23811 @defvr {Scheme Variable} php-fpm-service-type
23812 A Service type for @code{php-fpm}.
23815 @deftp {Data Type} php-fpm-configuration
23816 Data Type for php-fpm service configuration.
23818 @item @code{php} (default: @code{php})
23819 The php package to use.
23820 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
23821 The address on which to accept FastCGI requests. Valid syntaxes are:
23823 @item @code{"ip.add.re.ss:port"}
23824 Listen on a TCP socket to a specific address on a specific port.
23825 @item @code{"port"}
23826 Listen on a TCP socket to all addresses on a specific port.
23827 @item @code{"/path/to/unix/socket"}
23828 Listen on a unix socket.
23831 @item @code{user} (default: @code{php-fpm})
23832 User who will own the php worker processes.
23833 @item @code{group} (default: @code{php-fpm})
23834 Group of the worker processes.
23835 @item @code{socket-user} (default: @code{php-fpm})
23836 User who can speak to the php-fpm socket.
23837 @item @code{socket-group} (default: @code{nginx})
23838 Group that can speak to the php-fpm socket.
23839 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
23840 The process id of the php-fpm process is written to this file
23841 once the service has started.
23842 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
23843 Log for the php-fpm master process.
23844 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
23845 Detailed settings for the php-fpm process manager.
23848 @item @code{<php-fpm-dynamic-process-manager-configuration>}
23849 @item @code{<php-fpm-static-process-manager-configuration>}
23850 @item @code{<php-fpm-on-demand-process-manager-configuration>}
23852 @item @code{display-errors} (default @code{#f})
23853 Determines whether php errors and warning should be sent to clients
23854 and displayed in their browsers.
23855 This is useful for local php development, but a security risk for public sites,
23856 as error messages can reveal passwords and personal data.
23857 @item @code{timezone} (default @code{#f})
23858 Specifies @code{php_admin_value[date.timezone]} parameter.
23859 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
23860 This file will log the @code{stderr} outputs of php worker processes.
23861 Can be set to @code{#f} to disable logging.
23862 @item @code{file} (default @code{#f})
23863 An optional override of the whole configuration.
23864 You can use the @code{mixed-text-file} function or an absolute filepath for it.
23865 @item @code{php-ini-file} (default @code{#f})
23866 An optional override of the default php settings.
23867 It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
23868 You can use the @code{mixed-text-file} function or an absolute filepath for it.
23870 For local development it is useful to set a higher timeout and memory
23871 limit for spawned php processes. This be accomplished with the
23872 following operating system configuration snippet:
23874 (define %local-php-ini
23875 (plain-file "php.ini"
23877 max_execution_time = 1800"))
23881 (services (cons (service php-fpm-service-type
23882 (php-fpm-configuration
23883 (php-ini-file %local-php-ini)))
23887 Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
23888 directives} for comprehensive documentation on the acceptable
23889 @file{php.ini} directives.
23893 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
23894 Data Type for the @code{dynamic} php-fpm process manager. With the
23895 @code{dynamic} process manager, spare worker processes are kept around
23896 based on it's configured limits.
23898 @item @code{max-children} (default: @code{5})
23899 Maximum of worker processes.
23900 @item @code{start-servers} (default: @code{2})
23901 How many worker processes should be started on start-up.
23902 @item @code{min-spare-servers} (default: @code{1})
23903 How many spare worker processes should be kept around at minimum.
23904 @item @code{max-spare-servers} (default: @code{3})
23905 How many spare worker processes should be kept around at maximum.
23909 @deftp {Data type} php-fpm-static-process-manager-configuration
23910 Data Type for the @code{static} php-fpm process manager. With the
23911 @code{static} process manager, an unchanging number of worker processes
23914 @item @code{max-children} (default: @code{5})
23915 Maximum of worker processes.
23919 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
23920 Data Type for the @code{on-demand} php-fpm process manager. With the
23921 @code{on-demand} process manager, worker processes are only created as
23924 @item @code{max-children} (default: @code{5})
23925 Maximum of worker processes.
23926 @item @code{process-idle-timeout} (default: @code{10})
23927 The time in seconds after which a process with no requests is killed.
23932 @deffn {Scheme Procedure} nginx-php-location @
23933 [#:nginx-package nginx] @
23934 [socket (string-append "/var/run/php" @
23935 (version-major (package-version php)) @
23937 A helper function to quickly add php to an @code{nginx-server-configuration}.
23940 A simple services setup for nginx with php can look like this:
23942 (services (cons* (service dhcp-client-service-type)
23943 (service php-fpm-service-type)
23944 (service nginx-service-type
23945 (nginx-server-configuration
23946 (server-name '("example.com"))
23947 (root "/srv/http/")
23949 (list (nginx-php-location)))
23951 (ssl-certificate #f)
23952 (ssl-certificate-key #f)))
23956 @cindex cat-avatar-generator
23957 The cat avatar generator is a simple service to demonstrate the use of php-fpm
23958 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
23959 the hash of a user's email address.
23961 @deffn {Scheme Procedure} cat-avatar-generator-service @
23962 [#:cache-dir "/var/cache/cat-avatar-generator"] @
23963 [#:package cat-avatar-generator] @
23964 [#:configuration (nginx-server-configuration)]
23965 Returns an nginx-server-configuration that inherits @code{configuration}. It
23966 extends the nginx configuration to add a server block that serves @code{package},
23967 a version of cat-avatar-generator. During execution, cat-avatar-generator will
23968 be able to use @code{cache-dir} as its cache directory.
23971 A simple setup for cat-avatar-generator can look like this:
23973 (services (cons* (cat-avatar-generator-service
23975 (nginx-server-configuration
23976 (server-name '("example.com"))))
23981 @subsubheading Hpcguix-web
23983 @cindex hpcguix-web
23984 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
23985 program is a customizable web interface to browse Guix packages,
23986 initially designed for users of high-performance computing (HPC)
23989 @defvr {Scheme Variable} hpcguix-web-service-type
23990 The service type for @code{hpcguix-web}.
23993 @deftp {Data Type} hpcguix-web-configuration
23994 Data type for the hpcguix-web service configuration.
23998 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
23999 configuration. The main items available in this spec are:
24002 @item @code{title-prefix} (default: @code{"hpcguix | "})
24003 The page title prefix.
24005 @item @code{guix-command} (default: @code{"guix"})
24006 The @command{guix} command.
24008 @item @code{package-filter-proc} (default: @code{(const #t)})
24009 A procedure specifying how to filter packages that are displayed.
24011 @item @code{package-page-extension-proc} (default: @code{(const '())})
24012 Extension package for @code{hpcguix-web}.
24014 @item @code{menu} (default: @code{'()})
24015 Additional entry in page @code{menu}.
24017 @item @code{channels} (default: @code{%default-channels})
24018 List of channels from which the package list is built (@pxref{Channels}).
24020 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
24021 The expiration time, in seconds, after which the package list is rebuilt from
24022 the latest instances of the given channels.
24025 See the hpcguix-web repository for a
24026 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
24029 @item @code{package} (default: @code{hpcguix-web})
24030 The hpcguix-web package to use.
24034 A typical hpcguix-web service declaration looks like this:
24037 (service hpcguix-web-service-type
24038 (hpcguix-web-configuration
24040 #~(define site-config
24041 (hpcweb-configuration
24042 (title-prefix "Guix-HPC - ")
24043 (menu '(("/about" "ABOUT"))))))))
24047 The hpcguix-web service periodically updates the package list it publishes by
24048 pulling channels from Git. To that end, it needs to access X.509 certificates
24049 so that it can authenticate Git servers when communicating over HTTPS, and it
24050 assumes that @file{/etc/ssl/certs} contains those certificates.
24052 Thus, make sure to add @code{nss-certs} or another certificate package to the
24053 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
24054 more information on X.509 certificates.
24057 @subsubheading gmnisrv
24060 The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
24061 simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
24063 @deffn {Scheme Variable} gmnisrv-service-type
24064 This is the type of the gmnisrv service, whose value should be a
24065 @code{gmnisrv-configuration} object, as in this example:
24068 (service gmnisrv-service-type
24069 (gmnisrv-configuration
24070 (config-file (local-file "./my-gmnisrv.ini"))))
24074 @deftp {Data Type} gmnisrv-configuration
24075 Data type representing the configuration of gmnisrv.
24078 @item @code{package} (default: @var{gmnisrv})
24079 Package object of the gmnisrv server.
24081 @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
24082 File-like object of the gmnisrv configuration file to use. The default
24083 configuration listens on port 1965 and serves files from
24084 @file{/srv/gemini}. Certificates are stored in
24085 @file{/var/lib/gemini/certs}. For more information, run @command{man
24086 gmnisrv} and @command{man gmnisrv.ini}.
24091 @node Certificate Services
24092 @subsection Certificate Services
24095 @cindex HTTP, HTTPS
24096 @cindex Let's Encrypt
24097 @cindex TLS certificates
24098 The @code{(gnu services certbot)} module provides a service to
24099 automatically obtain a valid TLS certificate from the Let's Encrypt
24100 certificate authority. These certificates can then be used to serve
24101 content securely over HTTPS or other TLS-based protocols, with the
24102 knowledge that the client will be able to verify the server's
24105 @url{https://letsencrypt.org/, Let's Encrypt} provides the
24106 @code{certbot} tool to automate the certification process. This tool
24107 first securely generates a key on the server. It then makes a request
24108 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
24109 checks that the request originates from the host in question by using a
24110 challenge-response protocol, requiring the server to provide its
24111 response over HTTP. If that protocol completes successfully, the CA
24112 signs the key, resulting in a certificate. That certificate is valid
24113 for a limited period of time, and therefore to continue to provide TLS
24114 services, the server needs to periodically ask the CA to renew its
24117 The certbot service automates this process: the initial key
24118 generation, the initial certification request to the Let's Encrypt
24119 service, the web server challenge/response integration, writing the
24120 certificate to disk, the automated periodic renewals, and the deployment
24121 tasks associated with the renewal (e.g.@: reloading services, copying keys
24122 with different permissions).
24124 Certbot is run twice a day, at a random minute within the hour. It
24125 won't do anything until your certificates are due for renewal or
24126 revoked, but running it regularly would give your service a chance of
24127 staying online in case a Let's Encrypt-initiated revocation happened for
24130 By using this service, you agree to the ACME Subscriber Agreement, which
24131 can be found there:
24132 @url{https://acme-v01.api.letsencrypt.org/directory}.
24134 @defvr {Scheme Variable} certbot-service-type
24135 A service type for the @code{certbot} Let's Encrypt client. Its value
24136 must be a @code{certbot-configuration} record as in this example:
24139 (define %nginx-deploy-hook
24141 "nginx-deploy-hook"
24142 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
24143 (kill pid SIGHUP))))
24145 (service certbot-service-type
24146 (certbot-configuration
24147 (email "foo@@example.net")
24150 (certificate-configuration
24151 (domains '("example.net" "www.example.net"))
24152 (deploy-hook %nginx-deploy-hook))
24153 (certificate-configuration
24154 (domains '("bar.example.net")))))))
24157 See below for details about @code{certbot-configuration}.
24160 @deftp {Data Type} certbot-configuration
24161 Data type representing the configuration of the @code{certbot} service.
24162 This type has the following parameters:
24165 @item @code{package} (default: @code{certbot})
24166 The certbot package to use.
24168 @item @code{webroot} (default: @code{/var/www})
24169 The directory from which to serve the Let's Encrypt challenge/response
24172 @item @code{certificates} (default: @code{()})
24173 A list of @code{certificates-configuration}s for which to generate
24174 certificates and request signatures. Each certificate has a @code{name}
24175 and several @code{domains}.
24177 @item @code{email} (default: @code{#f})
24178 Optional email address used for registration and recovery contact.
24179 Setting this is encouraged as it allows you to receive important
24180 notifications about the account and issued certificates.
24182 @item @code{server} (default: @code{#f})
24183 Optional URL of ACME server. Setting this overrides certbot's default,
24184 which is the Let's Encrypt server.
24186 @item @code{rsa-key-size} (default: @code{2048})
24187 Size of the RSA key.
24189 @item @code{default-location} (default: @i{see below})
24190 The default @code{nginx-location-configuration}. Because @code{certbot}
24191 needs to be able to serve challenges and responses, it needs to be able
24192 to run a web server. It does so by extending the @code{nginx} web
24193 service with an @code{nginx-server-configuration} listening on the
24194 @var{domains} on port 80, and which has a
24195 @code{nginx-location-configuration} for the @code{/.well-known/} URI
24196 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
24197 these nginx configuration data types.
24199 Requests to other URL paths will be matched by the
24200 @code{default-location}, which if present is added to all
24201 @code{nginx-server-configuration}s.
24203 By default, the @code{default-location} will issue a redirect from
24204 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
24205 you to define what to serve on your site via @code{https}.
24207 Pass @code{#f} to not issue a default location.
24211 @deftp {Data Type} certificate-configuration
24212 Data type representing the configuration of a certificate.
24213 This type has the following parameters:
24216 @item @code{name} (default: @i{see below})
24217 This name is used by Certbot for housekeeping and in file paths; it
24218 doesn't affect the content of the certificate itself. To see
24219 certificate names, run @code{certbot certificates}.
24221 Its default is the first provided domain.
24223 @item @code{domains} (default: @code{()})
24224 The first domain provided will be the subject CN of the certificate, and
24225 all domains will be Subject Alternative Names on the certificate.
24227 @item @code{challenge} (default: @code{#f})
24228 The challenge type that has to be run by certbot. If @code{#f} is specified,
24229 default to the HTTP challenge. If a value is specified, defaults to the
24230 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
24231 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
24232 and gives Let's Encrypt permission to log the public IP address of the
24233 requesting machine.
24235 @item @code{authentication-hook} (default: @code{#f})
24236 Command to be run in a shell once for each certificate challenge to be
24237 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
24238 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
24239 contains the validation string and @code{$CERTBOT_TOKEN} contains the
24240 file name of the resource requested when performing an HTTP-01 challenge.
24242 @item @code{cleanup-hook} (default: @code{#f})
24243 Command to be run in a shell once for each certificate challenge that
24244 have been answered by the @code{auth-hook}. For this command, the shell
24245 variables available in the @code{auth-hook} script are still available, and
24246 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
24247 of the @code{auth-hook} script.
24249 @item @code{deploy-hook} (default: @code{#f})
24250 Command to be run in a shell once for each successfully issued
24251 certificate. For this command, the shell variable
24252 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
24253 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
24254 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
24255 contain a space-delimited list of renewed certificate domains (for
24256 example, @samp{"example.com www.example.com"}.
24261 For each @code{certificate-configuration}, the certificate is saved to
24262 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
24263 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
24265 @subsection DNS Services
24266 @cindex DNS (domain name system)
24267 @cindex domain name system (DNS)
24269 The @code{(gnu services dns)} module provides services related to the
24270 @dfn{domain name system} (DNS). It provides a server service for hosting
24271 an @emph{authoritative} DNS server for multiple zones, slave or master.
24272 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
24273 caching and forwarding DNS server for the LAN, which uses
24274 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
24276 @subsubheading Knot Service
24278 An example configuration of an authoritative server for two zones, one master
24282 (define-zone-entries example.org.zone
24283 ;; Name TTL Class Type Data
24284 ("@@" "" "IN" "A" "127.0.0.1")
24285 ("@@" "" "IN" "NS" "ns")
24286 ("ns" "" "IN" "A" "127.0.0.1"))
24288 (define master-zone
24289 (knot-zone-configuration
24290 (domain "example.org")
24292 (origin "example.org")
24293 (entries example.org.zone)))))
24296 (knot-zone-configuration
24297 (domain "plop.org")
24298 (dnssec-policy "default")
24299 (master (list "plop-master"))))
24301 (define plop-master
24302 (knot-remote-configuration
24304 (address (list "208.76.58.171"))))
24308 (services (cons* (service knot-service-type
24309 (knot-configuration
24310 (remotes (list plop-master))
24311 (zones (list master-zone slave-zone))))
24316 @deffn {Scheme Variable} knot-service-type
24317 This is the type for the Knot DNS server.
24319 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
24320 zones, that is to say domain names you would buy from a registrar. This server
24321 is not a resolver, meaning that it can only resolve names for which it is
24322 authoritative. This server can be configured to serve zones as a master server
24323 or a slave server as a per-zone basis. Slave zones will get their data from
24324 masters, and will serve it as an authoritative server. From the point of view
24325 of a resolver, there is no difference between master and slave.
24327 The following data types are used to configure the Knot DNS server:
24330 @deftp {Data Type} knot-key-configuration
24331 Data type representing a key.
24332 This type has the following parameters:
24335 @item @code{id} (default: @code{""})
24336 An identifier for other configuration fields to refer to this key. IDs must
24337 be unique and must not be empty.
24339 @item @code{algorithm} (default: @code{#f})
24340 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
24341 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
24342 and @code{'hmac-sha512}.
24344 @item @code{secret} (default: @code{""})
24345 The secret key itself.
24350 @deftp {Data Type} knot-acl-configuration
24351 Data type representing an Access Control List (ACL) configuration.
24352 This type has the following parameters:
24355 @item @code{id} (default: @code{""})
24356 An identifier for other configuration fields to refer to this key. IDs must be
24357 unique and must not be empty.
24359 @item @code{address} (default: @code{'()})
24360 An ordered list of IP addresses, network subnets, or network ranges represented
24361 with strings. The query must match one of them. Empty value means that
24362 address match is not required.
24364 @item @code{key} (default: @code{'()})
24365 An ordered list of references to keys represented with strings. The string
24366 must match a key ID defined in a @code{knot-key-configuration}. No key means
24367 that a key is not require to match that ACL.
24369 @item @code{action} (default: @code{'()})
24370 An ordered list of actions that are permitted or forbidden by this ACL. Possible
24371 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
24372 and @code{'update}.
24374 @item @code{deny?} (default: @code{#f})
24375 When true, the ACL defines restrictions. Listed actions are forbidden. When
24376 false, listed actions are allowed.
24381 @deftp {Data Type} zone-entry
24382 Data type representing a record entry in a zone file.
24383 This type has the following parameters:
24386 @item @code{name} (default: @code{"@@"})
24387 The name of the record. @code{"@@"} refers to the origin of the zone. Names
24388 are relative to the origin of the zone. For example, in the @code{example.org}
24389 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
24390 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
24391 refers to @code{ns.example.org}.
24393 @item @code{ttl} (default: @code{""})
24394 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
24396 @item @code{class} (default: @code{"IN"})
24397 The class of the record. Knot currently supports only @code{"IN"} and
24398 partially @code{"CH"}.
24400 @item @code{type} (default: @code{"A"})
24401 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
24402 address), NS (Name Server) and MX (Mail eXchange). Many other types are
24405 @item @code{data} (default: @code{""})
24406 The data contained in the record. For instance an IP address associated with
24407 an A record, or a domain name associated with an NS record. Remember that
24408 domain names are relative to the origin unless they end with a dot.
24413 @deftp {Data Type} zone-file
24414 Data type representing the content of a zone file.
24415 This type has the following parameters:
24418 @item @code{entries} (default: @code{'()})
24419 The list of entries. The SOA record is taken care of, so you don't need to
24420 put it in the list of entries. This list should probably contain an entry
24421 for your primary authoritative DNS server. Other than using a list of entries
24422 directly, you can use @code{define-zone-entries} to define a object containing
24423 the list of entries more easily, that you can later pass to the @code{entries}
24424 field of the @code{zone-file}.
24426 @item @code{origin} (default: @code{""})
24427 The name of your zone. This parameter cannot be empty.
24429 @item @code{ns} (default: @code{"ns"})
24430 The domain of your primary authoritative DNS server. The name is relative to
24431 the origin, unless it ends with a dot. It is mandatory that this primary
24432 DNS server corresponds to an NS record in the zone and that it is associated
24433 to an IP address in the list of entries.
24435 @item @code{mail} (default: @code{"hostmaster"})
24436 An email address people can contact you at, as the owner of the zone. This
24437 is translated as @code{<mail>@@<origin>}.
24439 @item @code{serial} (default: @code{1})
24440 The serial number of the zone. As this is used to keep track of changes by
24441 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
24442 Always increment it when you make a change in your zone.
24444 @item @code{refresh} (default: @code{(* 2 24 3600)})
24445 The frequency at which slaves will do a zone transfer. This value is a number
24446 of seconds. It can be computed by multiplications or with
24447 @code{(string->duration)}.
24449 @item @code{retry} (default: @code{(* 15 60)})
24450 The period after which a slave will retry to contact its master when it fails
24451 to do so a first time.
24453 @item @code{expiry} (default: @code{(* 14 24 3600)})
24454 Default TTL of records. Existing records are considered correct for at most
24455 this amount of time. After this period, resolvers will invalidate their cache
24456 and check again that it still exists.
24458 @item @code{nx} (default: @code{3600})
24459 Default TTL of inexistant records. This delay is usually short because you want
24460 your new domains to reach everyone quickly.
24465 @deftp {Data Type} knot-remote-configuration
24466 Data type representing a remote configuration.
24467 This type has the following parameters:
24470 @item @code{id} (default: @code{""})
24471 An identifier for other configuration fields to refer to this remote. IDs must
24472 be unique and must not be empty.
24474 @item @code{address} (default: @code{'()})
24475 An ordered list of destination IP addresses. Addresses are tried in sequence.
24476 An optional port can be given with the @@ separator. For instance:
24477 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
24479 @item @code{via} (default: @code{'()})
24480 An ordered list of source IP addresses. An empty list will have Knot choose
24481 an appropriate source IP. An optional port can be given with the @@ separator.
24482 The default is to choose at random.
24484 @item @code{key} (default: @code{#f})
24485 A reference to a key, that is a string containing the identifier of a key
24486 defined in a @code{knot-key-configuration} field.
24491 @deftp {Data Type} knot-keystore-configuration
24492 Data type representing a keystore to hold dnssec keys.
24493 This type has the following parameters:
24496 @item @code{id} (default: @code{""})
24497 The id of the keystore. It must not be empty.
24499 @item @code{backend} (default: @code{'pem})
24500 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
24502 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
24503 The configuration string of the backend. An example for the PKCS#11 is:
24504 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
24505 For the pem backend, the string represents a path in the file system.
24510 @deftp {Data Type} knot-policy-configuration
24511 Data type representing a dnssec policy. Knot DNS is able to automatically
24512 sign your zones. It can either generate and manage your keys automatically or
24513 use keys that you generate.
24515 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
24516 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
24517 zone. In order to be trusted, the KSK needs to be present in the parent zone
24518 (usually a top-level domain). If your registrar supports dnssec, you will
24519 have to send them your KSK's hash so they can add a DS record in their zone.
24520 This is not automated and need to be done each time you change your KSK.
24522 The policy also defines the lifetime of keys. Usually, ZSK can be changed
24523 easily and use weaker cryptographic functions (they use lower parameters) in
24524 order to sign records quickly, so they are changed often. The KSK however
24525 requires manual interaction with the registrar, so they are changed less often
24526 and use stronger parameters because they sign only one record.
24528 This type has the following parameters:
24531 @item @code{id} (default: @code{""})
24532 The id of the policy. It must not be empty.
24534 @item @code{keystore} (default: @code{"default"})
24535 A reference to a keystore, that is a string containing the identifier of a
24536 keystore defined in a @code{knot-keystore-configuration} field. The
24537 @code{"default"} identifier means the default keystore (a kasp database that
24538 was setup by this service).
24540 @item @code{manual?} (default: @code{#f})
24541 Whether the key management is manual or automatic.
24543 @item @code{single-type-signing?} (default: @code{#f})
24544 When @code{#t}, use the Single-Type Signing Scheme.
24546 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
24547 An algorithm of signing keys and issued signatures.
24549 @item @code{ksk-size} (default: @code{256})
24550 The length of the KSK. Note that this value is correct for the default
24551 algorithm, but would be unsecure for other algorithms.
24553 @item @code{zsk-size} (default: @code{256})
24554 The length of the ZSK. Note that this value is correct for the default
24555 algorithm, but would be unsecure for other algorithms.
24557 @item @code{dnskey-ttl} (default: @code{'default})
24558 The TTL value for DNSKEY records added into zone apex. The special
24559 @code{'default} value means same as the zone SOA TTL.
24561 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
24562 The period between ZSK publication and the next rollover initiation.
24564 @item @code{propagation-delay} (default: @code{(* 24 3600)})
24565 An extra delay added for each key rollover step. This value should be high
24566 enough to cover propagation of data from the master server to all slaves.
24568 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
24569 A validity period of newly issued signatures.
24571 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
24572 A period how long before a signature expiration the signature will be refreshed.
24574 @item @code{nsec3?} (default: @code{#f})
24575 When @code{#t}, NSEC3 will be used instead of NSEC.
24577 @item @code{nsec3-iterations} (default: @code{5})
24578 The number of additional times the hashing is performed.
24580 @item @code{nsec3-salt-length} (default: @code{8})
24581 The length of a salt field in octets, which is appended to the original owner
24582 name before hashing.
24584 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
24585 The validity period of newly issued salt field.
24590 @deftp {Data Type} knot-zone-configuration
24591 Data type representing a zone served by Knot.
24592 This type has the following parameters:
24595 @item @code{domain} (default: @code{""})
24596 The domain served by this configuration. It must not be empty.
24598 @item @code{file} (default: @code{""})
24599 The file where this zone is saved. This parameter is ignored by master zones.
24600 Empty means default location that depends on the domain name.
24602 @item @code{zone} (default: @code{(zone-file)})
24603 The content of the zone file. This parameter is ignored by slave zones. It
24604 must contain a zone-file record.
24606 @item @code{master} (default: @code{'()})
24607 A list of master remotes. When empty, this zone is a master. When set, this
24608 zone is a slave. This is a list of remotes identifiers.
24610 @item @code{ddns-master} (default: @code{#f})
24611 The main master. When empty, it defaults to the first master in the list of
24614 @item @code{notify} (default: @code{'()})
24615 A list of slave remote identifiers.
24617 @item @code{acl} (default: @code{'()})
24618 A list of acl identifiers.
24620 @item @code{semantic-checks?} (default: @code{#f})
24621 When set, this adds more semantic checks to the zone.
24623 @item @code{disable-any?} (default: @code{#f})
24624 When set, this forbids queries of the ANY type.
24626 @item @code{zonefile-sync} (default: @code{0})
24627 The delay between a modification in memory and on disk. 0 means immediate
24630 @item @code{zonefile-load} (default: @code{#f})
24631 The way the zone file contents are applied during zone load. Possible values
24635 @item @code{#f} for using the default value from Knot,
24636 @item @code{'none} for not using the zone file at all,
24637 @item @code{'difference} for computing the difference between already available
24638 contents and zone contents and applying it to the current zone contents,
24639 @item @code{'difference-no-serial} for the same as @code{'difference}, but
24640 ignoring the SOA serial in the zone file, while the server takes care of it
24642 @item @code{'whole} for loading zone contents from the zone file.
24645 @item @code{journal-content} (default: @code{#f})
24646 The way the journal is used to store zone and its changes. Possible values
24647 are @code{'none} to not use it at all, @code{'changes} to store changes and
24648 @code{'all} to store contents. @code{#f} does not set this option, so the
24649 default value from Knot is used.
24651 @item @code{max-journal-usage} (default: @code{#f})
24652 The maximum size for the journal on disk. @code{#f} does not set this option,
24653 so the default value from Knot is used.
24655 @item @code{max-journal-depth} (default: @code{#f})
24656 The maximum size of the history. @code{#f} does not set this option, so the
24657 default value from Knot is used.
24659 @item @code{max-zone-size} (default: @code{#f})
24660 The maximum size of the zone file. This limit is enforced for incoming
24661 transfer and updates. @code{#f} does not set this option, so the default
24662 value from Knot is used.
24664 @item @code{dnssec-policy} (default: @code{#f})
24665 A reference to a @code{knot-policy-configuration} record, or the special
24666 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
24669 @item @code{serial-policy} (default: @code{'increment})
24670 A policy between @code{'increment} and @code{'unixtime}.
24675 @deftp {Data Type} knot-configuration
24676 Data type representing the Knot configuration.
24677 This type has the following parameters:
24680 @item @code{knot} (default: @code{knot})
24683 @item @code{run-directory} (default: @code{"/var/run/knot"})
24684 The run directory. This directory will be used for pid file and sockets.
24686 @item @code{includes} (default: @code{'()})
24687 A list of strings or file-like objects denoting other files that must be
24688 included at the top of the configuration file.
24690 @cindex secrets, Knot service
24691 This can be used to manage secrets out-of-band. For example, secret
24692 keys may be stored in an out-of-band file not managed by Guix, and
24693 thus not visible in @file{/gnu/store}---e.g., you could store secret
24694 key configuration in @file{/etc/knot/secrets.conf} and add this file
24695 to the @code{includes} list.
24697 One can generate a secret tsig key (for nsupdate and zone transfers with the
24698 keymgr command from the knot package. Note that the package is not automatically
24699 installed by the service. The following example shows how to generate a new
24703 keymgr -t mysecret > /etc/knot/secrets.conf
24704 chmod 600 /etc/knot/secrets.conf
24707 Also note that the generated key will be named @var{mysecret}, so it is the
24708 name that needs to be used in the @var{key} field of the
24709 @code{knot-acl-configuration} record and in other places that need to refer
24712 It can also be used to add configuration not supported by this interface.
24714 @item @code{listen-v4} (default: @code{"0.0.0.0"})
24715 An ip address on which to listen.
24717 @item @code{listen-v6} (default: @code{"::"})
24718 An ip address on which to listen.
24720 @item @code{listen-port} (default: @code{53})
24721 A port on which to listen.
24723 @item @code{keys} (default: @code{'()})
24724 The list of knot-key-configuration used by this configuration.
24726 @item @code{acls} (default: @code{'()})
24727 The list of knot-acl-configuration used by this configuration.
24729 @item @code{remotes} (default: @code{'()})
24730 The list of knot-remote-configuration used by this configuration.
24732 @item @code{zones} (default: @code{'()})
24733 The list of knot-zone-configuration used by this configuration.
24738 @subsubheading Knot Resolver Service
24740 @deffn {Scheme Variable} knot-resolver-service-type
24741 This is the type of the knot resolver service, whose value should be
24742 an @code{knot-resolver-configuration} object as in this example:
24745 (service knot-resolver-service-type
24746 (knot-resolver-configuration
24747 (kresd-config-file (plain-file "kresd.conf" "
24748 net.listen('192.168.0.1', 5353)
24749 user('knot-resolver', 'knot-resolver')
24750 modules = @{ 'hints > iterate', 'stats', 'predict' @}
24751 cache.size = 100 * MB
24755 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
24758 @deftp {Data Type} knot-resolver-configuration
24759 Data type representing the configuration of knot-resolver.
24762 @item @code{package} (default: @var{knot-resolver})
24763 Package object of the knot DNS resolver.
24765 @item @code{kresd-config-file} (default: %kresd.conf)
24766 File-like object of the kresd configuration file to use, by default it
24767 will listen on @code{127.0.0.1} and @code{::1}.
24769 @item @code{garbage-collection-interval} (default: 1000)
24770 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
24776 @subsubheading Dnsmasq Service
24778 @deffn {Scheme Variable} dnsmasq-service-type
24779 This is the type of the dnsmasq service, whose value should be an
24780 @code{dnsmasq-configuration} object as in this example:
24783 (service dnsmasq-service-type
24784 (dnsmasq-configuration
24786 (servers '("192.168.1.1"))))
24790 @deftp {Data Type} dnsmasq-configuration
24791 Data type representing the configuration of dnsmasq.
24794 @item @code{package} (default: @var{dnsmasq})
24795 Package object of the dnsmasq server.
24797 @item @code{no-hosts?} (default: @code{#f})
24798 When true, don't read the hostnames in /etc/hosts.
24800 @item @code{port} (default: @code{53})
24801 The port to listen on. Setting this to zero completely disables DNS
24802 responses, leaving only DHCP and/or TFTP functions.
24804 @item @code{local-service?} (default: @code{#t})
24805 Accept DNS queries only from hosts whose address is on a local subnet,
24806 ie a subnet for which an interface exists on the server.
24808 @item @code{listen-addresses} (default: @code{'()})
24809 Listen on the given IP addresses.
24811 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
24812 The file to read the IP address of the upstream nameservers from.
24814 @item @code{no-resolv?} (default: @code{#f})
24815 When true, don't read @var{resolv-file}.
24817 @item @code{servers} (default: @code{'()})
24818 Specify IP address of upstream servers directly.
24820 @item @code{addresses} (default: @code{'()})
24821 For each entry, specify an IP address to return for any host in the
24822 given domains. Queries in the domains are never forwarded and always
24823 replied to with the specified IP address.
24825 This is useful for redirecting hosts locally, for example:
24828 (service dnsmasq-service-type
24829 (dnsmasq-configuration
24831 '(; Redirect to a local web-server.
24832 "/example.org/127.0.0.1"
24833 ; Redirect subdomain to a specific IP.
24834 "/subdomain.example.org/192.168.1.42"))))
24837 Note that rules in @file{/etc/hosts} take precedence over this.
24839 @item @code{cache-size} (default: @code{150})
24840 Set the size of dnsmasq's cache. Setting the cache size to zero
24843 @item @code{negative-cache?} (default: @code{#t})
24844 When false, disable negative caching.
24846 @item @code{tftp-enable?} (default: @code{#f})
24847 Whether to enable the built-in TFTP server.
24849 @item @code{tftp-no-fail?} (default: @code{#f})
24850 If true, does not fail dnsmasq if the TFTP server could not start up.
24852 @item @code{tftp-single-port?} (default: @code{#f})
24853 Whether to use only one single port for TFTP.
24855 @item @code{tftp-secure?} (default: @code{#f})
24856 If true, only files owned by the user running the dnsmasq process are accessible.
24858 If dnsmasq is being run as root, different rules apply:
24859 @code{tftp-secure?} has no effect, but only files which have the
24860 world-readable bit set are accessible.
24862 @item @code{tftp-max} (default: @code{#f})
24863 If set, sets the maximal number of concurrent connections allowed.
24865 @item @code{tftp-mtu} (default: @code{#f})
24866 If set, sets the MTU for TFTP packets to that value.
24868 @item @code{tftp-no-blocksize?} (default: @code{#f})
24869 If true, stops the TFTP server from negotiating the blocksize with a client.
24871 @item @code{tftp-lowercase?} (default: @code{#f})
24872 Whether to convert all filenames in TFTP requests to lowercase.
24874 @item @code{tftp-port-range} (default: @code{#f})
24875 If set, fixes the dynamical ports (one per client) to the given range
24876 (@code{"<start>,<end>"}).
24878 @item @code{tftp-root} (default: @code{/var/empty,lo})
24879 Look for files to transfer using TFTP relative to the given directory.
24880 When this is set, TFTP paths which include ".." are rejected, to stop clients
24881 getting outside the specified root. Absolute paths (starting with /) are
24882 allowed, but they must be within the tftp-root. If the optional interface
24883 argument is given, the directory is only used for TFTP requests via that
24886 @item @code{tftp-unique-root} (default: @code{#f})
24887 If set, add the IP or hardware address of the TFTP client as a path component
24888 on the end of the TFTP-root. Only valid if a TFTP root is set and the
24889 directory exists. Defaults to adding IP address (in standard dotted-quad
24892 For instance, if --tftp-root is "/tftp" and client 1.2.3.4 requests file
24893 "myfile" then the effective path will be "/tftp/1.2.3.4/myfile" if
24894 /tftp/1.2.3.4 exists or /tftp/myfile otherwise. When "=mac" is specified
24895 it will append the MAC address instead, using lowercase zero padded digits
24896 separated by dashes, e.g.: 01-02-03-04-aa-bb Note that resolving MAC
24897 addresses is only possible if the client is in the local network or obtained
24898 a DHCP lease from dnsmasq.
24903 @subsubheading ddclient Service
24906 The ddclient service described below runs the ddclient daemon, which takes
24907 care of automatically updating DNS entries for service providers such as
24908 @uref{https://dyn.com/dns/, Dyn}.
24910 The following example show instantiates the service with its default
24914 (service ddclient-service-type)
24917 Note that ddclient needs to access credentials that are stored in a
24918 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
24919 @code{secret-file} below). You are expected to create this file manually, in
24920 an ``out-of-band'' fashion (you @emph{could} make this file part of the
24921 service configuration, for instance by using @code{plain-file}, but it will be
24922 world-readable @i{via} @file{/gnu/store}). See the examples in the
24923 @file{share/ddclient} directory of the @code{ddclient} package.
24925 @c %start of fragment
24927 Available @code{ddclient-configuration} fields are:
24929 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
24930 The ddclient package.
24934 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
24935 The period after which ddclient will retry to check IP and domain name.
24937 Defaults to @samp{300}.
24941 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
24942 Use syslog for the output.
24944 Defaults to @samp{#t}.
24948 @deftypevr {@code{ddclient-configuration} parameter} string mail
24951 Defaults to @samp{"root"}.
24955 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
24956 Mail failed update to user.
24958 Defaults to @samp{"root"}.
24962 @deftypevr {@code{ddclient-configuration} parameter} string pid
24963 The ddclient PID file.
24965 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
24969 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
24970 Enable SSL support.
24972 Defaults to @samp{#t}.
24976 @deftypevr {@code{ddclient-configuration} parameter} string user
24977 Specifies the user name or ID that is used when running ddclient
24980 Defaults to @samp{"ddclient"}.
24984 @deftypevr {@code{ddclient-configuration} parameter} string group
24985 Group of the user who will run the ddclient program.
24987 Defaults to @samp{"ddclient"}.
24991 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
24992 Secret file which will be appended to @file{ddclient.conf} file. This
24993 file contains credentials for use by ddclient. You are expected to
24994 create it manually.
24996 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
25000 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
25001 Extra options will be appended to @file{ddclient.conf} file.
25003 Defaults to @samp{()}.
25008 @c %end of fragment
25012 @subsection VPN Services
25013 @cindex VPN (virtual private network)
25014 @cindex virtual private network (VPN)
25016 The @code{(gnu services vpn)} module provides services related to
25017 @dfn{virtual private networks} (VPNs). It provides a @emph{client} service for
25018 your machine to connect to a VPN, and a @emph{server} service for your machine
25019 to host a VPN. Both services use @uref{https://openvpn.net/, OpenVPN}.
25021 @deffn {Scheme Procedure} openvpn-client-service @
25022 [#:config (openvpn-client-configuration)]
25024 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
25027 @deffn {Scheme Procedure} openvpn-server-service @
25028 [#:config (openvpn-server-configuration)]
25030 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
25032 Both can be run simultaneously.
25035 @c %automatically generated documentation
25037 Available @code{openvpn-client-configuration} fields are:
25039 @deftypevr {@code{openvpn-client-configuration} parameter} package openvpn
25040 The OpenVPN package.
25044 @deftypevr {@code{openvpn-client-configuration} parameter} string pid-file
25045 The OpenVPN pid file.
25047 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
25051 @deftypevr {@code{openvpn-client-configuration} parameter} proto proto
25052 The protocol (UDP or TCP) used to open a channel between clients and
25055 Defaults to @samp{udp}.
25059 @deftypevr {@code{openvpn-client-configuration} parameter} dev dev
25060 The device type used to represent the VPN connection.
25062 Defaults to @samp{tun}.
25066 If you do not have some of these files (eg.@: you use a username and
25067 password), you can disable any of the following three fields by setting
25068 it to @code{'disabled}.
25070 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string ca
25071 The certificate authority to check connections against.
25073 Defaults to @samp{"/etc/openvpn/ca.crt"}.
25077 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string cert
25078 The certificate of the machine the daemon is running on. It should be
25079 signed by the authority given in @code{ca}.
25081 Defaults to @samp{"/etc/openvpn/client.crt"}.
25085 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string key
25086 The key of the machine the daemon is running on. It must be the key whose
25087 certificate is @code{cert}.
25089 Defaults to @samp{"/etc/openvpn/client.key"}.
25093 @deftypevr {@code{openvpn-client-configuration} parameter} boolean comp-lzo?
25094 Whether to use the lzo compression algorithm.
25096 Defaults to @samp{#t}.
25100 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-key?
25101 Don't re-read key files across SIGUSR1 or --ping-restart.
25103 Defaults to @samp{#t}.
25107 @deftypevr {@code{openvpn-client-configuration} parameter} boolean persist-tun?
25108 Don't close and reopen TUN/TAP device or run up/down scripts across
25109 SIGUSR1 or --ping-restart restarts.
25111 Defaults to @samp{#t}.
25115 @deftypevr {@code{openvpn-client-configuration} parameter} boolean fast-io?
25116 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
25117 poll/epoll/select prior to the write operation.
25119 Defaults to @samp{#f}.
25122 @deftypevr {@code{openvpn-client-configuration} parameter} number verbosity
25125 Defaults to @samp{3}.
25129 @deftypevr {@code{openvpn-client-configuration} parameter} tls-auth-client tls-auth
25130 Add an additional layer of HMAC authentication on top of the TLS control
25131 channel to protect against DoS attacks.
25133 Defaults to @samp{#f}.
25137 @deftypevr {@code{openvpn-client-configuration} parameter} maybe-string auth-user-pass
25138 Authenticate with server using username/password. The option is a file
25139 containing username/password on 2 lines. Do not use a file-like object as it
25140 would be added to the store and readable by any user.
25142 Defaults to @samp{'disabled}.
25145 @deftypevr {@code{openvpn-client-configuration} parameter} key-usage verify-key-usage?
25146 Whether to check the server certificate has server usage extension.
25148 Defaults to @samp{#t}.
25152 @deftypevr {@code{openvpn-client-configuration} parameter} bind bind?
25153 Bind to a specific local port number.
25155 Defaults to @samp{#f}.
25159 @deftypevr {@code{openvpn-client-configuration} parameter} resolv-retry resolv-retry?
25160 Retry resolving server address.
25162 Defaults to @samp{#t}.
25166 @deftypevr {@code{openvpn-client-configuration} parameter} openvpn-remote-list remote
25167 A list of remote servers to connect to.
25169 Defaults to @samp{()}.
25171 Available @code{openvpn-remote-configuration} fields are:
25173 @deftypevr {@code{openvpn-remote-configuration} parameter} string name
25176 Defaults to @samp{"my-server"}.
25180 @deftypevr {@code{openvpn-remote-configuration} parameter} number port
25181 Port number the server listens to.
25183 Defaults to @samp{1194}.
25188 @c %end of automatic openvpn-client documentation
25190 @c %automatically generated documentation
25192 Available @code{openvpn-server-configuration} fields are:
25194 @deftypevr {@code{openvpn-server-configuration} parameter} package openvpn
25195 The OpenVPN package.
25199 @deftypevr {@code{openvpn-server-configuration} parameter} string pid-file
25200 The OpenVPN pid file.
25202 Defaults to @samp{"/var/run/openvpn/openvpn.pid"}.
25206 @deftypevr {@code{openvpn-server-configuration} parameter} proto proto
25207 The protocol (UDP or TCP) used to open a channel between clients and
25210 Defaults to @samp{udp}.
25214 @deftypevr {@code{openvpn-server-configuration} parameter} dev dev
25215 The device type used to represent the VPN connection.
25217 Defaults to @samp{tun}.
25221 If you do not have some of these files (eg.@: you use a username and
25222 password), you can disable any of the following three fields by setting
25223 it to @code{'disabled}.
25225 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string ca
25226 The certificate authority to check connections against.
25228 Defaults to @samp{"/etc/openvpn/ca.crt"}.
25232 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string cert
25233 The certificate of the machine the daemon is running on. It should be
25234 signed by the authority given in @code{ca}.
25236 Defaults to @samp{"/etc/openvpn/client.crt"}.
25240 @deftypevr {@code{openvpn-server-configuration} parameter} maybe-string key
25241 The key of the machine the daemon is running on. It must be the key whose
25242 certificate is @code{cert}.
25244 Defaults to @samp{"/etc/openvpn/client.key"}.
25248 @deftypevr {@code{openvpn-server-configuration} parameter} boolean comp-lzo?
25249 Whether to use the lzo compression algorithm.
25251 Defaults to @samp{#t}.
25255 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-key?
25256 Don't re-read key files across SIGUSR1 or --ping-restart.
25258 Defaults to @samp{#t}.
25262 @deftypevr {@code{openvpn-server-configuration} parameter} boolean persist-tun?
25263 Don't close and reopen TUN/TAP device or run up/down scripts across
25264 SIGUSR1 or --ping-restart restarts.
25266 Defaults to @samp{#t}.
25270 @deftypevr {@code{openvpn-server-configuration} parameter} boolean fast-io?
25271 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
25272 poll/epoll/select prior to the write operation.
25274 Defaults to @samp{#f}.
25277 @deftypevr {@code{openvpn-server-configuration} parameter} number verbosity
25280 Defaults to @samp{3}.
25284 @deftypevr {@code{openvpn-server-configuration} parameter} tls-auth-server tls-auth
25285 Add an additional layer of HMAC authentication on top of the TLS control
25286 channel to protect against DoS attacks.
25288 Defaults to @samp{#f}.
25292 @deftypevr {@code{openvpn-server-configuration} parameter} number port
25293 Specifies the port number on which the server listens.
25295 Defaults to @samp{1194}.
25299 @deftypevr {@code{openvpn-server-configuration} parameter} ip-mask server
25300 An ip and mask specifying the subnet inside the virtual network.
25302 Defaults to @samp{"10.8.0.0 255.255.255.0"}.
25306 @deftypevr {@code{openvpn-server-configuration} parameter} cidr6 server-ipv6
25307 A CIDR notation specifying the IPv6 subnet inside the virtual network.
25309 Defaults to @samp{#f}.
25313 @deftypevr {@code{openvpn-server-configuration} parameter} string dh
25314 The Diffie-Hellman parameters file.
25316 Defaults to @samp{"/etc/openvpn/dh2048.pem"}.
25320 @deftypevr {@code{openvpn-server-configuration} parameter} string ifconfig-pool-persist
25321 The file that records client IPs.
25323 Defaults to @samp{"/etc/openvpn/ipp.txt"}.
25327 @deftypevr {@code{openvpn-server-configuration} parameter} gateway redirect-gateway?
25328 When true, the server will act as a gateway for its clients.
25330 Defaults to @samp{#f}.
25334 @deftypevr {@code{openvpn-server-configuration} parameter} boolean client-to-client?
25335 When true, clients are allowed to talk to each other inside the VPN.
25337 Defaults to @samp{#f}.
25341 @deftypevr {@code{openvpn-server-configuration} parameter} keepalive keepalive
25342 Causes ping-like messages to be sent back and forth over the link so
25343 that each side knows when the other side has gone down. @code{keepalive}
25344 requires a pair. The first element is the period of the ping sending,
25345 and the second element is the timeout before considering the other side
25350 @deftypevr {@code{openvpn-server-configuration} parameter} number max-clients
25351 The maximum number of clients.
25353 Defaults to @samp{100}.
25357 @deftypevr {@code{openvpn-server-configuration} parameter} string status
25358 The status file. This file shows a small report on current connection.
25359 It is truncated and rewritten every minute.
25361 Defaults to @samp{"/var/run/openvpn/status"}.
25365 @deftypevr {@code{openvpn-server-configuration} parameter} openvpn-ccd-list client-config-dir
25366 The list of configuration for some clients.
25368 Defaults to @samp{()}.
25370 Available @code{openvpn-ccd-configuration} fields are:
25372 @deftypevr {@code{openvpn-ccd-configuration} parameter} string name
25375 Defaults to @samp{"client"}.
25379 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask iroute
25382 Defaults to @samp{#f}.
25386 @deftypevr {@code{openvpn-ccd-configuration} parameter} ip-mask ifconfig-push
25389 Defaults to @samp{#f}.
25396 @c %end of automatic openvpn-server documentation
25399 @node Network File System
25400 @subsection Network File System
25403 The @code{(gnu services nfs)} module provides the following services,
25404 which are most commonly used in relation to mounting or exporting
25405 directory trees as @dfn{network file systems} (NFS).
25407 While it is possible to use the individual components that together make
25408 up a Network File System service, we recommended to configure an NFS
25409 server with the @code{nfs-service-type}.
25411 @subsubheading NFS Service
25412 @cindex NFS, server
25414 The NFS service takes care of setting up all NFS component services,
25415 kernel configuration file systems, and installs configuration files in
25416 the locations that NFS expects.
25418 @defvr {Scheme Variable} nfs-service-type
25419 A service type for a complete NFS server.
25422 @deftp {Data Type} nfs-configuration
25423 This data type represents the configuration of the NFS service and all
25426 It has the following parameters:
25428 @item @code{nfs-utils} (default: @code{nfs-utils})
25429 The nfs-utils package to use.
25431 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
25432 If a list of string values is provided, the @command{rpc.nfsd} daemon
25433 will be limited to supporting the given versions of the NFS protocol.
25435 @item @code{exports} (default: @code{'()})
25436 This is a list of directories the NFS server should export. Each entry
25437 is a list consisting of two elements: a directory name and a string
25438 containing all options. This is an example in which the directory
25439 @file{/export} is served to all NFS clients as a read-only share:
25445 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
25448 @item @code{rpcmountd-port} (default: @code{#f})
25449 The network port that the @command{rpc.mountd} daemon should use.
25451 @item @code{rpcstatd-port} (default: @code{#f})
25452 The network port that the @command{rpc.statd} daemon should use.
25454 @item @code{rpcbind} (default: @code{rpcbind})
25455 The rpcbind package to use.
25457 @item @code{idmap-domain} (default: @code{"localdomain"})
25458 The local NFSv4 domain name.
25460 @item @code{nfsd-port} (default: @code{2049})
25461 The network port that the @command{nfsd} daemon should use.
25463 @item @code{nfsd-threads} (default: @code{8})
25464 The number of threads used by the @command{nfsd} daemon.
25466 @item @code{nfsd-tcp?} (default: @code{#t})
25467 Whether the @command{nfsd} daemon should listen on a TCP socket.
25469 @item @code{nfsd-udp?} (default: @code{#f})
25470 Whether the @command{nfsd} daemon should listen on a UDP socket.
25472 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
25473 The directory where the pipefs file system is mounted.
25475 @item @code{debug} (default: @code{'()"})
25476 A list of subsystems for which debugging output should be enabled. This
25477 is a list of symbols. Any of these symbols are valid: @code{nfsd},
25478 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
25482 If you don't need a complete NFS service or prefer to build it yourself
25483 you can use the individual component services that are documented below.
25485 @subsubheading RPC Bind Service
25488 The RPC Bind service provides a facility to map program numbers into
25489 universal addresses.
25490 Many NFS related services use this facility. Hence it is automatically
25491 started when a dependent service starts.
25493 @defvr {Scheme Variable} rpcbind-service-type
25494 A service type for the RPC portmapper daemon.
25498 @deftp {Data Type} rpcbind-configuration
25499 Data type representing the configuration of the RPC Bind Service.
25500 This type has the following parameters:
25502 @item @code{rpcbind} (default: @code{rpcbind})
25503 The rpcbind package to use.
25505 @item @code{warm-start?} (default: @code{#t})
25506 If this parameter is @code{#t}, then the daemon will read a
25507 state file on startup thus reloading state information saved by a previous
25513 @subsubheading Pipefs Pseudo File System
25517 The pipefs file system is used to transfer NFS related data
25518 between the kernel and user space programs.
25520 @defvr {Scheme Variable} pipefs-service-type
25521 A service type for the pipefs pseudo file system.
25524 @deftp {Data Type} pipefs-configuration
25525 Data type representing the configuration of the pipefs pseudo file system service.
25526 This type has the following parameters:
25528 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
25529 The directory to which the file system is to be attached.
25534 @subsubheading GSS Daemon Service
25537 @cindex global security system
25539 The @dfn{global security system} (GSS) daemon provides strong security for RPC
25541 Before exchanging RPC requests an RPC client must establish a security
25542 context. Typically this is done using the Kerberos command @command{kinit}
25543 or automatically at login time using PAM services (@pxref{Kerberos Services}).
25545 @defvr {Scheme Variable} gss-service-type
25546 A service type for the Global Security System (GSS) daemon.
25549 @deftp {Data Type} gss-configuration
25550 Data type representing the configuration of the GSS daemon service.
25551 This type has the following parameters:
25553 @item @code{nfs-utils} (default: @code{nfs-utils})
25554 The package in which the @command{rpc.gssd} command is to be found.
25556 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
25557 The directory where the pipefs file system is mounted.
25563 @subsubheading IDMAP Daemon Service
25565 @cindex name mapper
25567 The idmap daemon service provides mapping between user IDs and user names.
25568 Typically it is required in order to access file systems mounted via NFSv4.
25570 @defvr {Scheme Variable} idmap-service-type
25571 A service type for the Identity Mapper (IDMAP) daemon.
25574 @deftp {Data Type} idmap-configuration
25575 Data type representing the configuration of the IDMAP daemon service.
25576 This type has the following parameters:
25578 @item @code{nfs-utils} (default: @code{nfs-utils})
25579 The package in which the @command{rpc.idmapd} command is to be found.
25581 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
25582 The directory where the pipefs file system is mounted.
25584 @item @code{domain} (default: @code{#f})
25585 The local NFSv4 domain name.
25586 This must be a string or @code{#f}.
25587 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
25589 @item @code{verbosity} (default: @code{0})
25590 The verbosity level of the daemon.
25595 @node Continuous Integration
25596 @subsection Continuous Integration
25598 @cindex continuous integration
25599 @uref{https://git.savannah.gnu.org/cgit/guix/guix-cuirass.git, Cuirass} is a
25600 continuous integration tool for Guix. It can be used both for development and
25601 for providing substitutes to others (@pxref{Substitutes}).
25603 The @code{(gnu services cuirass)} module provides the following service.
25605 @defvr {Scheme Procedure} cuirass-service-type
25606 The type of the Cuirass service. Its value must be a
25607 @code{cuirass-configuration} object, as described below.
25610 To add build jobs, you have to set the @code{specifications} field of the
25611 configuration. Here is an example of a service that polls the Guix repository
25612 and builds the packages from a manifest. Some of the packages are defined in
25613 the @code{"custom-packages"} input, which is the equivalent of
25614 @env{GUIX_PACKAGE_PATH}.
25617 (define %cuirass-specs
25619 '((#:name . "my-manifest")
25620 (#:load-path-inputs . ("guix"))
25621 (#:package-path-inputs . ("custom-packages"))
25622 (#:proc-input . "guix")
25623 (#:proc-file . "build-aux/cuirass/gnu-system.scm")
25624 (#:proc . cuirass-jobs)
25625 (#:proc-args . ((subset . "manifests")
25626 (systems . ("x86_64-linux"))
25627 (manifests . (("config" . "guix/manifest.scm")))))
25628 (#:inputs . (((#:name . "guix")
25629 (#:url . "git://git.savannah.gnu.org/guix.git")
25630 (#:load-path . ".")
25631 (#:branch . "master")
25632 (#:no-compile? . #t))
25633 ((#:name . "config")
25634 (#:url . "https://git.example.org/config.git")
25635 (#:load-path . ".")
25636 (#:branch . "master")
25637 (#:no-compile? . #t))
25638 ((#:name . "custom-packages")
25639 (#:url . "https://git.example.org/custom-packages.git")
25640 (#:load-path . ".")
25641 (#:branch . "master")
25642 (#:no-compile? . #t)))))))
25644 (service cuirass-service-type
25645 (cuirass-configuration
25646 (specifications %cuirass-specs)))
25649 While information related to build jobs is located directly in the
25650 specifications, global settings for the @command{cuirass} process are
25651 accessible in other @code{cuirass-configuration} fields.
25653 @deftp {Data Type} cuirass-configuration
25654 Data type representing the configuration of Cuirass.
25657 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
25658 Location of the log file.
25660 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
25661 Location of the log file used by the web interface.
25663 @item @code{queries-log-file} (default: @code{#f})
25664 Location of the SQL queries log file. By default, SQL queries logging is
25667 @item @code{web-queries-log-file} (default: @code{#f})
25668 Location of the web SQL queries log file. By default, web SQL queries
25669 logging is disabled.
25671 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
25672 Location of the repository cache.
25674 @item @code{user} (default: @code{"cuirass"})
25675 Owner of the @code{cuirass} process.
25677 @item @code{group} (default: @code{"cuirass"})
25678 Owner's group of the @code{cuirass} process.
25680 @item @code{interval} (default: @code{60})
25681 Number of seconds between the poll of the repositories followed by the
25684 @item @code{database} (default: @code{"/var/lib/cuirass/cuirass.db"})
25685 Location of sqlite database which contains the build results and previously
25686 added specifications.
25688 @item @code{ttl} (default: @code{(* 30 24 3600)})
25689 Specifies the time-to-live (TTL) in seconds of garbage collector roots that
25690 are registered for build results. This means that build results are protected
25691 from garbage collection for at least @var{ttl} seconds.
25693 @item @code{port} (default: @code{8081})
25694 Port number used by the HTTP server.
25696 @item @code{host} (default: @code{"localhost"})
25697 Listen on the network interface for @var{host}. The default is to
25698 accept connections from localhost.
25700 @item @code{specifications} (default: @code{#~'()})
25701 A gexp (@pxref{G-Expressions}) that evaluates to a list of specifications,
25702 where a specification is an association list
25703 (@pxref{Associations Lists,,, guile, GNU Guile Reference Manual}) whose
25704 keys are keywords (@code{#:keyword-example}) as shown in the example
25707 @item @code{use-substitutes?} (default: @code{#f})
25708 This allows using substitutes to avoid building every dependencies of a job
25711 @item @code{one-shot?} (default: @code{#f})
25712 Only evaluate specifications and build derivations once.
25714 @item @code{fallback?} (default: @code{#f})
25715 When substituting a pre-built binary fails, fall back to building
25718 @item @code{extra-options} (default: @code{'()})
25719 Extra options to pass when running the Cuirass processes.
25721 @item @code{cuirass} (default: @code{cuirass})
25722 The Cuirass package to use.
25726 @node Power Management Services
25727 @subsection Power Management Services
25730 @cindex power management with TLP
25731 @subsubheading TLP daemon
25733 The @code{(gnu services pm)} module provides a Guix service definition
25734 for the Linux power management tool TLP.
25736 TLP enables various powersaving modes in userspace and kernel.
25737 Contrary to @code{upower-service}, it is not a passive,
25738 monitoring tool, as it will apply custom settings each time a new power
25739 source is detected. More information can be found at
25740 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
25742 @deffn {Scheme Variable} tlp-service-type
25743 The service type for the TLP tool. The default settings are optimised
25744 for battery life on most systems, but you can tweak them to your heart's
25745 content by adding a valid @code{tlp-configuration}:
25747 (service tlp-service-type
25749 (cpu-scaling-governor-on-ac (list "performance"))
25750 (sched-powersave-on-bat? #t)))
25754 Each parameter definition is preceded by its type; for example,
25755 @samp{boolean foo} indicates that the @code{foo} parameter
25756 should be specified as a boolean. Types starting with
25757 @code{maybe-} denote parameters that won't show up in TLP config file
25758 when their value is @code{'disabled}.
25760 @c The following documentation was initially generated by
25761 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
25762 @c documentation is better, so we shouldn't hesitate to edit below as
25763 @c needed. However if the change you want to make to this documentation
25764 @c can be done in an automated way, it's probably easier to change
25765 @c (generate-documentation) than to make it below and have to deal with
25766 @c the churn as TLP updates.
25768 Available @code{tlp-configuration} fields are:
25770 @deftypevr {@code{tlp-configuration} parameter} package tlp
25775 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
25776 Set to true if you wish to enable TLP.
25778 Defaults to @samp{#t}.
25782 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
25783 Default mode when no power supply can be detected. Alternatives are AC
25786 Defaults to @samp{"AC"}.
25790 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
25791 Number of seconds Linux kernel has to wait after the disk goes idle,
25792 before syncing on AC.
25794 Defaults to @samp{0}.
25798 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
25799 Same as @code{disk-idle-ac} but on BAT mode.
25801 Defaults to @samp{2}.
25805 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
25806 Dirty pages flushing periodicity, expressed in seconds.
25808 Defaults to @samp{15}.
25812 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
25813 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
25815 Defaults to @samp{60}.
25819 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
25820 CPU frequency scaling governor on AC mode. With intel_pstate driver,
25821 alternatives are powersave and performance. With acpi-cpufreq driver,
25822 alternatives are ondemand, powersave, performance and conservative.
25824 Defaults to @samp{disabled}.
25828 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
25829 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
25831 Defaults to @samp{disabled}.
25835 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
25836 Set the min available frequency for the scaling governor on AC.
25838 Defaults to @samp{disabled}.
25842 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
25843 Set the max available frequency for the scaling governor on AC.
25845 Defaults to @samp{disabled}.
25849 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
25850 Set the min available frequency for the scaling governor on BAT.
25852 Defaults to @samp{disabled}.
25856 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
25857 Set the max available frequency for the scaling governor on BAT.
25859 Defaults to @samp{disabled}.
25863 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
25864 Limit the min P-state to control the power dissipation of the CPU, in AC
25865 mode. Values are stated as a percentage of the available performance.
25867 Defaults to @samp{disabled}.
25871 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
25872 Limit the max P-state to control the power dissipation of the CPU, in AC
25873 mode. Values are stated as a percentage of the available performance.
25875 Defaults to @samp{disabled}.
25879 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
25880 Same as @code{cpu-min-perf-on-ac} on BAT mode.
25882 Defaults to @samp{disabled}.
25886 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
25887 Same as @code{cpu-max-perf-on-ac} on BAT mode.
25889 Defaults to @samp{disabled}.
25893 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
25894 Enable CPU turbo boost feature on AC mode.
25896 Defaults to @samp{disabled}.
25900 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
25901 Same as @code{cpu-boost-on-ac?} on BAT mode.
25903 Defaults to @samp{disabled}.
25907 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
25908 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
25909 used under light load conditions.
25911 Defaults to @samp{#f}.
25915 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
25916 Same as @code{sched-powersave-on-ac?} but on BAT mode.
25918 Defaults to @samp{#t}.
25922 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
25923 Enable Linux kernel NMI watchdog.
25925 Defaults to @samp{#f}.
25929 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
25930 For Linux kernels with PHC patch applied, change CPU voltages. An
25931 example value would be @samp{"F:V F:V F:V F:V"}.
25933 Defaults to @samp{disabled}.
25937 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
25938 Set CPU performance versus energy saving policy on AC. Alternatives are
25939 performance, normal, powersave.
25941 Defaults to @samp{"performance"}.
25945 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
25946 Same as @code{energy-perf-policy-ac} but on BAT mode.
25948 Defaults to @samp{"powersave"}.
25952 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
25957 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
25958 Hard disk advanced power management level.
25962 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
25963 Same as @code{disk-apm-bat} but on BAT mode.
25967 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
25968 Hard disk spin down timeout. One value has to be specified for each
25969 declared hard disk.
25971 Defaults to @samp{disabled}.
25975 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
25976 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
25978 Defaults to @samp{disabled}.
25982 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
25983 Select IO scheduler for disk devices. One value has to be specified for
25984 each declared hard disk. Example alternatives are cfq, deadline and
25987 Defaults to @samp{disabled}.
25991 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
25992 SATA aggressive link power management (ALPM) level. Alternatives are
25993 min_power, medium_power, max_performance.
25995 Defaults to @samp{"max_performance"}.
25999 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
26000 Same as @code{sata-linkpwr-ac} but on BAT mode.
26002 Defaults to @samp{"min_power"}.
26006 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
26007 Exclude specified SATA host devices for link power management.
26009 Defaults to @samp{disabled}.
26013 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
26014 Enable Runtime Power Management for AHCI controller and disks on AC
26017 Defaults to @samp{disabled}.
26021 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
26022 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
26024 Defaults to @samp{disabled}.
26028 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
26029 Seconds of inactivity before disk is suspended.
26031 Defaults to @samp{15}.
26035 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
26036 PCI Express Active State Power Management level. Alternatives are
26037 default, performance, powersave.
26039 Defaults to @samp{"performance"}.
26043 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
26044 Same as @code{pcie-aspm-ac} but on BAT mode.
26046 Defaults to @samp{"powersave"}.
26050 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
26051 Radeon graphics clock speed level. Alternatives are low, mid, high,
26054 Defaults to @samp{"high"}.
26058 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
26059 Same as @code{radeon-power-ac} but on BAT mode.
26061 Defaults to @samp{"low"}.
26065 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
26066 Radeon dynamic power management method (DPM). Alternatives are battery,
26069 Defaults to @samp{"performance"}.
26073 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
26074 Same as @code{radeon-dpm-state-ac} but on BAT mode.
26076 Defaults to @samp{"battery"}.
26080 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
26081 Radeon DPM performance level. Alternatives are auto, low, high.
26083 Defaults to @samp{"auto"}.
26087 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
26088 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
26090 Defaults to @samp{"auto"}.
26094 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
26095 Wifi power saving mode.
26097 Defaults to @samp{#f}.
26101 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
26102 Same as @code{wifi-power-ac?} but on BAT mode.
26104 Defaults to @samp{#t}.
26108 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
26109 Disable wake on LAN.
26111 Defaults to @samp{#t}.
26115 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
26116 Timeout duration in seconds before activating audio power saving on
26117 Intel HDA and AC97 devices. A value of 0 disables power saving.
26119 Defaults to @samp{0}.
26123 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
26124 Same as @code{sound-powersave-ac} but on BAT mode.
26126 Defaults to @samp{1}.
26130 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
26131 Disable controller in powersaving mode on Intel HDA devices.
26133 Defaults to @samp{#t}.
26137 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
26138 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
26139 powered on again by releasing (and reinserting) the eject lever or by
26140 pressing the disc eject button on newer models.
26142 Defaults to @samp{#f}.
26146 @deftypevr {@code{tlp-configuration} parameter} string bay-device
26147 Name of the optical drive device to power off.
26149 Defaults to @samp{"sr0"}.
26153 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
26154 Runtime Power Management for PCI(e) bus devices. Alternatives are on
26157 Defaults to @samp{"on"}.
26161 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
26162 Same as @code{runtime-pm-ac} but on BAT mode.
26164 Defaults to @samp{"auto"}.
26168 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
26169 Runtime Power Management for all PCI(e) bus devices, except blacklisted
26172 Defaults to @samp{#t}.
26176 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
26177 Exclude specified PCI(e) device addresses from Runtime Power Management.
26179 Defaults to @samp{disabled}.
26183 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
26184 Exclude PCI(e) devices assigned to the specified drivers from Runtime
26189 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
26190 Enable USB autosuspend feature.
26192 Defaults to @samp{#t}.
26196 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
26197 Exclude specified devices from USB autosuspend.
26199 Defaults to @samp{disabled}.
26203 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
26204 Exclude WWAN devices from USB autosuspend.
26206 Defaults to @samp{#t}.
26210 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
26211 Include specified devices into USB autosuspend, even if they are already
26212 excluded by the driver or via @code{usb-blacklist-wwan?}.
26214 Defaults to @samp{disabled}.
26218 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
26219 Enable USB autosuspend before shutdown.
26221 Defaults to @samp{disabled}.
26225 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
26226 Restore radio device state (bluetooth, wifi, wwan) from previous
26227 shutdown on system startup.
26229 Defaults to @samp{#f}.
26234 @cindex CPU frequency scaling with thermald
26235 @subsubheading Thermald daemon
26237 The @code{(gnu services pm)} module provides an interface to
26238 thermald, a CPU frequency scaling service which helps prevent overheating.
26240 @defvr {Scheme Variable} thermald-service-type
26241 This is the service type for
26242 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
26243 Thermal Daemon, which is responsible for controlling the thermal state
26244 of processors and preventing overheating.
26247 @deftp {Data Type} thermald-configuration
26248 Data type representing the configuration of @code{thermald-service-type}.
26251 @item @code{ignore-cpuid-check?} (default: @code{#f})
26252 Ignore cpuid check for supported CPU models.
26254 @item @code{thermald} (default: @var{thermald})
26255 Package object of thermald.
26260 @node Audio Services
26261 @subsection Audio Services
26263 The @code{(gnu services audio)} module provides a service to start MPD
26264 (the Music Player Daemon).
26267 @subsubheading Music Player Daemon
26269 The Music Player Daemon (MPD) is a service that can play music while
26270 being controlled from the local machine or over the network by a variety
26273 The following example shows how one might run @code{mpd} as user
26274 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
26277 (service mpd-service-type
26283 @defvr {Scheme Variable} mpd-service-type
26284 The service type for @command{mpd}
26287 @deftp {Data Type} mpd-configuration
26288 Data type representing the configuration of @command{mpd}.
26291 @item @code{user} (default: @code{"mpd"})
26292 The user to run mpd as.
26294 @item @code{music-dir} (default: @code{"~/Music"})
26295 The directory to scan for music files.
26297 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
26298 The directory to store playlists.
26300 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
26301 The location of the music database.
26303 @item @code{state-file} (default: @code{"~/.mpd/state"})
26304 The location of the file that stores current MPD's state.
26306 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
26307 The location of the sticker database.
26309 @item @code{port} (default: @code{"6600"})
26310 The port to run mpd on.
26312 @item @code{address} (default: @code{"any"})
26313 The address that mpd will bind to. To use a Unix domain socket,
26314 an absolute path can be specified here.
26316 @item @code{outputs} (default: @code{"(list (mpd-output))"})
26317 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
26322 @deftp {Data Type} mpd-output
26323 Data type representing an @command{mpd} audio output.
26326 @item @code{name} (default: @code{"MPD"})
26327 The name of the audio output.
26329 @item @code{type} (default: @code{"pulse"})
26330 The type of audio output.
26332 @item @code{enabled?} (default: @code{#t})
26333 Specifies whether this audio output is enabled when MPD is started. By
26334 default, all audio outputs are enabled. This is just the default
26335 setting when there is no state file; with a state file, the previous
26338 @item @code{tags?} (default: @code{#t})
26339 If set to @code{#f}, then MPD will not send tags to this output. This
26340 is only useful for output plugins that can receive tags, for example the
26341 @code{httpd} output plugin.
26343 @item @code{always-on?} (default: @code{#f})
26344 If set to @code{#t}, then MPD attempts to keep this audio output always
26345 open. This may be useful for streaming servers, when you don’t want to
26346 disconnect all listeners even when playback is accidentally stopped.
26348 @item @code{mixer-type}
26349 This field accepts a symbol that specifies which mixer should be used
26350 for this audio output: the @code{hardware} mixer, the @code{software}
26351 mixer, the @code{null} mixer (allows setting the volume, but with no
26352 effect; this can be used as a trick to implement an external mixer
26353 External Mixer) or no mixer (@code{none}).
26355 @item @code{extra-options} (default: @code{'()})
26356 An association list of option symbols to string values to be appended to
26357 the audio output configuration.
26362 The following example shows a configuration of @code{mpd} that provides
26363 an HTTP audio streaming output.
26366 (service mpd-service-type
26374 `((encoder . "vorbis")
26375 (port . "8080"))))))))
26379 @node Virtualization Services
26380 @subsection Virtualization Services
26382 The @code{(gnu services virtualization)} module provides services for
26383 the libvirt and virtlog daemons, as well as other virtualization-related
26386 @subsubheading Libvirt daemon
26388 @code{libvirtd} is the server side daemon component of the libvirt
26389 virtualization management system. This daemon runs on host servers
26390 and performs required management tasks for virtualized guests.
26392 @deffn {Scheme Variable} libvirt-service-type
26393 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
26394 Its value must be a @code{libvirt-configuration}.
26397 (service libvirt-service-type
26398 (libvirt-configuration
26399 (unix-sock-group "libvirt")
26400 (tls-port "16555")))
26404 @c Auto-generated with (generate-libvirt-documentation)
26405 Available @code{libvirt-configuration} fields are:
26407 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
26412 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
26413 Flag listening for secure TLS connections on the public TCP/IP port.
26414 You must set @code{listen} for this to have any effect.
26416 It is necessary to setup a CA and issue server certificates before using
26419 Defaults to @samp{#t}.
26423 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
26424 Listen for unencrypted TCP connections on the public TCP/IP port. You must
26425 set @code{listen} for this to have any effect.
26427 Using the TCP socket requires SASL authentication by default. Only SASL
26428 mechanisms which support data encryption are allowed. This is
26429 DIGEST_MD5 and GSSAPI (Kerberos5).
26431 Defaults to @samp{#f}.
26435 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
26436 Port for accepting secure TLS connections. This can be a port number,
26439 Defaults to @samp{"16514"}.
26443 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
26444 Port for accepting insecure TCP connections. This can be a port number,
26447 Defaults to @samp{"16509"}.
26451 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
26452 IP address or hostname used for client connections.
26454 Defaults to @samp{"0.0.0.0"}.
26458 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
26459 Flag toggling mDNS advertisement of the libvirt service.
26461 Alternatively can disable for all services on a host by stopping the
26464 Defaults to @samp{#f}.
26468 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
26469 Default mDNS advertisement name. This must be unique on the immediate
26472 Defaults to @samp{"Virtualization Host <hostname>"}.
26476 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
26477 UNIX domain socket group ownership. This can be used to allow a
26478 'trusted' set of users access to management capabilities without
26481 Defaults to @samp{"root"}.
26485 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
26486 UNIX socket permissions for the R/O socket. This is used for monitoring
26489 Defaults to @samp{"0777"}.
26493 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
26494 UNIX socket permissions for the R/W socket. Default allows only root.
26495 If PolicyKit is enabled on the socket, the default will change to allow
26496 everyone (eg, 0777)
26498 Defaults to @samp{"0770"}.
26502 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
26503 UNIX socket permissions for the admin socket. Default allows only owner
26504 (root), do not change it unless you are sure to whom you are exposing
26507 Defaults to @samp{"0777"}.
26511 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
26512 The directory in which sockets will be found/created.
26514 Defaults to @samp{"/var/run/libvirt"}.
26518 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
26519 Authentication scheme for UNIX read-only sockets. By default socket
26520 permissions allow anyone to connect
26522 Defaults to @samp{"polkit"}.
26526 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
26527 Authentication scheme for UNIX read-write sockets. By default socket
26528 permissions only allow root. If PolicyKit support was compiled into
26529 libvirt, the default will be to use 'polkit' auth.
26531 Defaults to @samp{"polkit"}.
26535 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
26536 Authentication scheme for TCP sockets. If you don't enable SASL, then
26537 all TCP traffic is cleartext. Don't do this outside of a dev/test
26540 Defaults to @samp{"sasl"}.
26544 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
26545 Authentication scheme for TLS sockets. TLS sockets already have
26546 encryption provided by the TLS layer, and limited authentication is done
26549 It is possible to make use of any SASL authentication mechanism as well,
26550 by using 'sasl' for this option
26552 Defaults to @samp{"none"}.
26556 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
26557 API access control scheme.
26559 By default an authenticated user is allowed access to all APIs. Access
26560 drivers can place restrictions on this.
26562 Defaults to @samp{()}.
26566 @deftypevr {@code{libvirt-configuration} parameter} string key-file
26567 Server key file path. If set to an empty string, then no private key is
26570 Defaults to @samp{""}.
26574 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
26575 Server key file path. If set to an empty string, then no certificate is
26578 Defaults to @samp{""}.
26582 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
26583 Server key file path. If set to an empty string, then no CA certificate
26586 Defaults to @samp{""}.
26590 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
26591 Certificate revocation list path. If set to an empty string, then no
26594 Defaults to @samp{""}.
26598 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
26599 Disable verification of our own server certificates.
26601 When libvirtd starts it performs some sanity checks against its own
26604 Defaults to @samp{#f}.
26608 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
26609 Disable verification of client certificates.
26611 Client certificate verification is the primary authentication mechanism.
26612 Any client which does not present a certificate signed by the CA will be
26615 Defaults to @samp{#f}.
26619 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
26620 Whitelist of allowed x509 Distinguished Name.
26622 Defaults to @samp{()}.
26626 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
26627 Whitelist of allowed SASL usernames. The format for username depends on
26628 the SASL authentication mechanism.
26630 Defaults to @samp{()}.
26634 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
26635 Override the compile time default TLS priority string. The default is
26636 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
26637 is desired for libvirt to deviate from the global default settings.
26639 Defaults to @samp{"NORMAL"}.
26643 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
26644 Maximum number of concurrent client connections to allow over all
26647 Defaults to @samp{5000}.
26651 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
26652 Maximum length of queue of connections waiting to be accepted by the
26653 daemon. Note, that some protocols supporting retransmission may obey
26654 this so that a later reattempt at connection succeeds.
26656 Defaults to @samp{1000}.
26660 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
26661 Maximum length of queue of accepted but not yet authenticated clients.
26662 Set this to zero to turn this feature off
26664 Defaults to @samp{20}.
26668 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
26669 Number of workers to start up initially.
26671 Defaults to @samp{5}.
26675 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
26676 Maximum number of worker threads.
26678 If the number of active clients exceeds @code{min-workers}, then more
26679 threads are spawned, up to max_workers limit. Typically you'd want
26680 max_workers to equal maximum number of clients allowed.
26682 Defaults to @samp{20}.
26686 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
26687 Number of priority workers. If all workers from above pool are stuck,
26688 some calls marked as high priority (notably domainDestroy) can be
26689 executed in this pool.
26691 Defaults to @samp{5}.
26695 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
26696 Total global limit on concurrent RPC calls.
26698 Defaults to @samp{20}.
26702 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
26703 Limit on concurrent requests from a single client connection. To avoid
26704 one client monopolizing the server this should be a small fraction of
26705 the global max_requests and max_workers parameter.
26707 Defaults to @samp{5}.
26711 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
26712 Same as @code{min-workers} but for the admin interface.
26714 Defaults to @samp{1}.
26718 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
26719 Same as @code{max-workers} but for the admin interface.
26721 Defaults to @samp{5}.
26725 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
26726 Same as @code{max-clients} but for the admin interface.
26728 Defaults to @samp{5}.
26732 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
26733 Same as @code{max-queued-clients} but for the admin interface.
26735 Defaults to @samp{5}.
26739 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
26740 Same as @code{max-client-requests} but for the admin interface.
26742 Defaults to @samp{5}.
26746 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
26747 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
26749 Defaults to @samp{3}.
26753 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
26756 A filter allows to select a different logging level for a given category
26757 of logs. The format for a filter is one of:
26768 where @code{name} is a string which is matched against the category
26769 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
26770 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
26771 name in the filter can be a substring of the full category name, in
26772 order to match multiple similar categories), the optional @samp{"+"}
26773 prefix tells libvirt to log stack trace for each message matching name,
26774 and @code{x} is the minimal level where matching messages should be
26792 Multiple filters can be defined in a single filters statement, they just
26793 need to be separated by spaces.
26795 Defaults to @samp{"3:remote 4:event"}.
26799 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
26802 An output is one of the places to save logging information. The format
26803 for an output can be:
26807 output goes to stderr
26809 @item x:syslog:name
26810 use syslog for the output and use the given name as the ident
26812 @item x:file:file_path
26813 output to a file, with the given filepath
26816 output to journald logging system
26820 In all case the x prefix is the minimal level, acting as a filter
26837 Multiple outputs can be defined, they just need to be separated by
26840 Defaults to @samp{"3:stderr"}.
26844 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
26845 Allows usage of the auditing subsystem to be altered
26849 0: disable all auditing
26852 1: enable auditing, only if enabled on host
26855 2: enable auditing, and exit if disabled on host.
26859 Defaults to @samp{1}.
26863 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
26864 Send audit messages via libvirt logging infrastructure.
26866 Defaults to @samp{#f}.
26870 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
26871 Host UUID. UUID must not have all digits be the same.
26873 Defaults to @samp{""}.
26877 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
26878 Source to read host UUID.
26882 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
26885 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
26889 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
26892 Defaults to @samp{"smbios"}.
26896 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
26897 A keepalive message is sent to a client after @code{keepalive_interval}
26898 seconds of inactivity to check if the client is still responding. If
26899 set to -1, libvirtd will never send keepalive requests; however clients
26900 can still send them and the daemon will send responses.
26902 Defaults to @samp{5}.
26906 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
26907 Maximum number of keepalive messages that are allowed to be sent to the
26908 client without getting any response before the connection is considered
26911 In other words, the connection is automatically closed approximately
26912 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
26913 the last message received from the client. When @code{keepalive-count}
26914 is set to 0, connections will be automatically closed after
26915 @code{keepalive-interval} seconds of inactivity without sending any
26916 keepalive messages.
26918 Defaults to @samp{5}.
26922 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
26923 Same as above but for admin interface.
26925 Defaults to @samp{5}.
26929 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
26930 Same as above but for admin interface.
26932 Defaults to @samp{5}.
26936 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
26937 Timeout for Open vSwitch calls.
26939 The @code{ovs-vsctl} utility is used for the configuration and its
26940 timeout option is set by default to 5 seconds to avoid potential
26941 infinite waits blocking libvirt.
26943 Defaults to @samp{5}.
26947 @c %end of autogenerated docs
26949 @subsubheading Virtlog daemon
26950 The virtlogd service is a server side daemon component of libvirt that is
26951 used to manage logs from virtual machine consoles.
26953 This daemon is not used directly by libvirt client applications, rather it
26954 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
26955 standalone daemon, the main @code{libvirtd} daemon can be restarted without
26956 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
26957 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
26959 @deffn {Scheme Variable} virtlog-service-type
26960 This is the type of the virtlog daemon.
26961 Its value must be a @code{virtlog-configuration}.
26964 (service virtlog-service-type
26965 (virtlog-configuration
26966 (max-clients 1000)))
26970 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
26971 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
26973 Defaults to @samp{3}.
26977 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
26980 A filter allows to select a different logging level for a given category
26981 of logs The format for a filter is one of:
26992 where @code{name} is a string which is matched against the category
26993 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
26994 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
26995 be a substring of the full category name, in order to match multiple
26996 similar categories), the optional "+" prefix tells libvirt to log stack
26997 trace for each message matching name, and @code{x} is the minimal level
26998 where matching messages should be logged:
27015 Multiple filters can be defined in a single filters statement, they just
27016 need to be separated by spaces.
27018 Defaults to @samp{"3:remote 4:event"}.
27022 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
27025 An output is one of the places to save logging information The format
27026 for an output can be:
27030 output goes to stderr
27032 @item x:syslog:name
27033 use syslog for the output and use the given name as the ident
27035 @item x:file:file_path
27036 output to a file, with the given filepath
27039 output to journald logging system
27043 In all case the x prefix is the minimal level, acting as a filter
27060 Multiple outputs can be defined, they just need to be separated by
27063 Defaults to @samp{"3:stderr"}.
27067 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
27068 Maximum number of concurrent client connections to allow over all
27071 Defaults to @samp{1024}.
27075 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
27076 Maximum file size before rolling over.
27078 Defaults to @samp{2MB}
27082 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
27083 Maximum number of backup files to keep.
27085 Defaults to @samp{3}
27089 @anchor{transparent-emulation-qemu}
27090 @subsubheading Transparent Emulation with QEMU
27093 @cindex @code{binfmt_misc}
27094 @code{qemu-binfmt-service-type} provides support for transparent
27095 emulation of program binaries built for different architectures---e.g.,
27096 it allows you to transparently execute an ARMv7 program on an x86_64
27097 machine. It achieves this by combining the @uref{https://www.qemu.org,
27098 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
27099 This feature only allows you to emulate GNU/Linux on a different
27100 architecture, but see below for GNU/Hurd support.
27102 @defvr {Scheme Variable} qemu-binfmt-service-type
27103 This is the type of the QEMU/binfmt service for transparent emulation.
27104 Its value must be a @code{qemu-binfmt-configuration} object, which
27105 specifies the QEMU package to use as well as the architecture we want to
27109 (service qemu-binfmt-service-type
27110 (qemu-binfmt-configuration
27111 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
27114 In this example, we enable transparent emulation for the ARM and aarch64
27115 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
27116 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
27117 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
27120 @deftp {Data Type} qemu-binfmt-configuration
27121 This is the configuration for the @code{qemu-binfmt} service.
27124 @item @code{platforms} (default: @code{'()})
27125 The list of emulated QEMU platforms. Each item must be a @dfn{platform
27126 object} as returned by @code{lookup-qemu-platforms} (see below).
27128 @item @code{guix-support?} (default: @code{#f})
27129 When it is true, QEMU and all its dependencies are added to the build
27130 environment of @command{guix-daemon} (@pxref{Invoking guix-daemon,
27131 @option{--chroot-directory} option}). This allows the @code{binfmt_misc}
27132 handlers to be used within the build environment, which in turn means
27133 that you can transparently build programs for another architecture.
27135 For example, let's suppose you're on an x86_64 machine and you have this
27139 (service qemu-binfmt-service-type
27140 (qemu-binfmt-configuration
27141 (platforms (lookup-qemu-platforms "arm"))
27142 (guix-support? #t)))
27148 guix build -s armhf-linux inkscape
27152 and it will build Inkscape for ARMv7 @emph{as if it were a native
27153 build}, transparently using QEMU to emulate the ARMv7 CPU. Pretty handy
27154 if you'd like to test a package build for an architecture you don't have
27157 @item @code{qemu} (default: @code{qemu})
27158 The QEMU package to use.
27162 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
27163 Return the list of QEMU platform objects corresponding to
27164 @var{platforms}@dots{}. @var{platforms} must be a list of strings
27165 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
27166 @code{"mips64el"}, and so on.
27169 @deffn {Scheme Procedure} qemu-platform? @var{obj}
27170 Return true if @var{obj} is a platform object.
27173 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
27174 Return the name of @var{platform}---a string such as @code{"arm"}.
27178 @subsubheading The Hurd in a Virtual Machine
27180 @cindex @code{hurd}
27184 Service @code{hurd-vm} provides support for running GNU/Hurd in a
27185 virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
27186 to be used on GNU/Linux and the given GNU/Hurd operating system
27187 configuration is cross-compiled. The virtual machine is a Shepherd
27188 service that can be referred to by the names @code{hurd-vm} and
27189 @code{childhurd} and be controlled with commands such as:
27193 herd stop childhurd
27196 When the service is running, you can view its console by connecting to
27197 it with a VNC client, for example with:
27200 guix environment --ad-hoc tigervnc-client -- \
27201 vncviewer localhost:5900
27204 The default configuration (see @code{hurd-vm-configuration} below)
27205 spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
27206 (the virtual machine emulator) redirects to port 10222 on the host.
27207 Thus, you can connect over SSH to the childhurd with:
27210 ssh root@@localhost -p 10022
27213 The childhurd is volatile and stateless: it starts with a fresh root
27214 file system every time you restart it. By default though, all the files
27215 under @file{/etc/childhurd} on the host are copied as is to the root
27216 file system of the childhurd when it boots. This allows you to
27217 initialize ``secrets'' inside the VM: SSH host keys, authorized
27218 substitute keys, and so on---see the explanation of @code{secret-root}
27221 @defvr {Scheme Variable} hurd-vm-service-type
27222 This is the type of the Hurd in a Virtual Machine service. Its value
27223 must be a @code{hurd-vm-configuration} object, which specifies the
27224 operating system (@pxref{operating-system Reference}) and the disk size
27225 for the Hurd Virtual Machine, the QEMU package to use as well as the
27226 options for running it.
27231 (service hurd-vm-service-type
27232 (hurd-vm-configuration
27233 (disk-size (* 5000 (expt 2 20))) ;5G
27234 (memory-size 1024))) ;1024MiB
27237 would create a disk image big enough to build GNU@tie{}Hello, with some
27241 @deftp {Data Type} hurd-vm-configuration
27242 The data type representing the configuration for
27243 @code{hurd-vm-service-type}.
27246 @item @code{os} (default: @var{%hurd-vm-operating-system})
27247 The operating system to instantiate. This default is bare-bones with a
27248 permissive OpenSSH secure shell daemon listening on port 2222
27249 (@pxref{Networking Services, @code{openssh-service-type}}).
27251 @item @code{qemu} (default: @code{qemu-minimal})
27252 The QEMU package to use.
27254 @item @code{image} (default: @var{hurd-vm-disk-image})
27255 The procedure used to build the disk-image built from this
27258 @item @code{disk-size} (default: @code{'guess})
27259 The size of the disk image.
27261 @item @code{memory-size} (default: @code{512})
27262 The memory size of the Virtual Machine in mebibytes.
27264 @item @code{options} (default: @code{'("--snapshot")})
27265 The extra options for running QEMU.
27267 @item @code{id} (default: @code{#f})
27268 If set, a non-zero positive integer used to parameterize Childhurd
27269 instances. It is appended to the service's name,
27270 e.g. @code{childhurd1}.
27272 @item @code{net-options} (default: @var{hurd-vm-net-options})
27273 The procedure used to produce the list of QEMU networking options.
27275 By default, it produces
27278 '("--device" "rtl8139,netdev=net0"
27279 "--netdev" "user,id=net0\
27280 ,hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004\
27281 ,hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222\
27282 ,hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900")
27285 with forwarded ports:
27288 @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
27289 @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
27290 @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
27293 @item @code{secret-root} (default: @file{/etc/childhurd})
27294 The root directory with out-of-band secrets to be installed into the
27295 childhurd once it runs. Childhurds are volatile which means that on
27296 every startup, secrets such as the SSH host keys and Guix signing key
27299 If the @file{/etc/childhurd} directory does not exist, the
27300 @code{secret-service} running in the Childhurd will be sent an empty
27303 By default, the service automatically populates @file{/etc/childhurd}
27304 with the following non-volatile secrets, unless they already exist:
27307 /etc/childhurd/etc/guix/acl
27308 /etc/childhurd/etc/guix/signing-key.pub
27309 /etc/childhurd/etc/guix/signing-key.sec
27310 /etc/childhurd/etc/ssh/ssh_host_ed25519_key
27311 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
27312 /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
27313 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
27316 These files are automatically sent to the guest Hurd VM when it boots,
27317 including permissions.
27319 @cindex childhurd, offloading
27320 @cindex Hurd, offloading
27321 Having these files in place means that only a couple of things are
27322 missing to allow the host to offload @code{i586-gnu} builds to the
27327 Authorizing the childhurd's key on the host so that the host accepts
27328 build results coming from the childhurd, which can be done like so:
27331 guix archive --authorize < \
27332 /etc/childhurd/etc/guix/signing-key.pub
27336 Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
27340 We're working towards making that happen automatically---get in touch
27341 with us at @email{guix-devel@@gnu.org} to discuss it!
27345 Note that by default the VM image is volatile, i.e., once stopped the
27346 contents are lost. If you want a stateful image instead, override the
27347 configuration's @code{image} and @code{options} without
27348 the @code{--snapshot} flag using something along these lines:
27351 (service hurd-vm-service-type
27352 (hurd-vm-configuration
27353 (image (const "/out/of/store/writable/hurd.img"))
27357 @subsubheading Ganeti
27362 This service is considered experimental. Configuration options may be changed
27363 in a backwards-incompatible manner, and not all features have been thorougly
27364 tested. Users of this service are encouraged to share their experience at
27365 @email{guix-devel@@gnu.org}.
27368 Ganeti is a virtual machine management system. It is designed to keep virtual
27369 machines running on a cluster of servers even in the event of hardware failures,
27370 and to make maintenance and recovery tasks easy. It consists of multiple
27371 services which are described later in this section. In addition to the Ganeti
27372 service, you will need the OpenSSH service (@pxref{Networking Services,
27373 @code{openssh-service-type}}), and update the @file{/etc/hosts} file
27374 (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
27375 and address (or use a DNS server).
27377 All nodes participating in a Ganeti cluster should have the same Ganeti and
27378 @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
27379 cluster node that supports multiple storage backends, and installs the
27380 @code{debootstrap} and @code{guix} @dfn{OS providers}:
27383 (use-package-modules virtualization)
27384 (use-service-modules base ganeti networking ssh)
27387 (host-name "node1")
27388 (hosts-file (plain-file "hosts" (format #f "
27389 127.0.0.1 localhost
27392 192.168.1.200 ganeti.example.com
27393 192.168.1.201 node1.example.com node1
27394 192.168.1.202 node2.example.com node2
27397 ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
27398 ;; in order to use the "plain", "drbd" and "rbd" storage backends.
27399 (packages (append (map specification->package
27400 '("qemu" "lvm2" "drbd-utils" "ceph"
27401 ;; Add the debootstrap and guix OS providers.
27402 "ganeti-instance-guix" "ganeti-instance-debootstrap"))
27405 (append (list (static-networking-service "eth0" "192.168.1.201"
27406 #:netmask "255.255.255.0"
27407 #:gateway "192.168.1.254"
27408 #:name-servers '("192.168.1.252"
27411 ;; Ganeti uses SSH to communicate between nodes.
27412 (service openssh-service-type
27413 (openssh-configuration
27414 (permit-root-login 'without-password)))
27416 (service ganeti-service-type
27417 (ganeti-configuration
27418 ;; This list specifies allowed file system paths
27419 ;; for storing virtual machine images.
27420 (file-storage-paths '("/srv/ganeti/file-storage"))
27421 ;; This variable configures a single "variant" for
27422 ;; both Debootstrap and Guix that works with KVM.
27423 (os %default-ganeti-os))))
27427 Users are advised to read the
27428 @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
27429 administrators guide} to learn about the various cluster options and
27430 day-to-day operations. There is also a
27431 @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
27432 describing how to configure and initialize a small cluster.
27434 @defvr {Scheme Variable} ganeti-service-type
27435 This is a service type that includes all the various services that Ganeti
27438 Its value is a @code{ganeti-configuration} object that defines the package
27439 to use for CLI operations, as well as configuration for the various daemons.
27440 Allowed file storage paths and available guest operating systems are also
27441 configured through this data type.
27444 @deftp {Data Type} ganeti-configuration
27445 The @code{ganeti} service takes the following configuration options:
27448 @item @code{ganeti} (default: @code{ganeti})
27449 The @code{ganeti} package to use. It will be installed to the system profile
27450 and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
27451 that the value specified here does not affect the other services as each refer
27452 to a specific @code{ganeti} package (see below).
27454 @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
27455 @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
27456 @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
27457 @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
27458 @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
27459 @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
27460 @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
27461 @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
27462 @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
27463 @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
27465 These options control the various daemons and cron jobs that are distributed
27466 with Ganeti. The possible values for these are described in detail below.
27467 To override a setting, you must use the configuration type for that service:
27470 (service ganeti-service-type
27471 (ganeti-configuration
27472 (rapi-configuration
27473 (ganeti-rapi-configuration
27474 (interface "eth1"))))
27475 (watcher-configuration
27476 (ganeti-watcher-configuration
27477 (rapi-ip "10.0.0.1"))))
27480 @item @code{file-storage-paths} (default: @code{'()})
27481 List of allowed directories for file storage backend.
27483 @item @code{os} (default: @code{%default-ganeti-os})
27484 List of @code{<ganeti-os>} records.
27487 In essence @code{ganeti-service-type} is shorthand for declaring each service
27491 (service ganeti-noded-service-type)
27492 (service ganeti-confd-service-type)
27493 (service ganeti-wconfd-service-type)
27494 (service ganeti-luxid-service-type)
27495 (service ganeti-kvmd-service-type)
27496 (service ganeti-mond-service-type)
27497 (service ganeti-metad-service-type)
27498 (service ganeti-watcher-service-type)
27499 (service ganeti-cleaner-service-type)
27502 Plus a service extension for @code{etc-service-type} that configures the file
27503 storage backend and OS variants.
27507 @deftp {Data Type} ganeti-os
27508 This data type is suitable for passing to the @code{os} parameter of
27509 @code{ganeti-configuration}. It takes the following parameters:
27513 The name for this OS provider. It is only used to specify where the
27514 configuration ends up. Setting it to ``debootstrap'' will create
27515 @file{/etc/ganeti/instance-debootstrap}.
27517 @item @code{extension}
27518 The file extension for variants of this OS type. For example
27519 @file{.conf} or @file{.scm}.
27521 @item @code{variants} (default: @code{'()})
27522 List of @code{ganeti-os-variant} objects for this OS.
27527 @deftp {Data Type} ganeti-os-variant
27528 This is the data type for a Ganeti OS variant. It takes the following
27533 The name of this variant.
27535 @item @code{configuration}
27536 A configuration file for this variant.
27540 @defvr {Scheme Variable} %default-debootstrap-hooks
27541 This variable contains hooks to configure networking and the GRUB bootloader.
27544 @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
27545 This variable contains a list of packages suitable for a fully-virtualized guest.
27548 @deftp {Data Type} debootstrap-configuration
27550 This data type creates configuration files suitable for the debootstrap OS provider.
27553 @item @code{hooks} (default: @code{%default-debootstrap-hooks})
27554 When not @code{#f}, this must be a G-expression that specifies a directory with
27555 scripts that will run when the OS is installed. It can also be a list of
27556 @code{(name . file-like)} pairs. For example:
27559 `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
27562 That will create a directory with one executable named @code{99-hello-world}
27563 and run it every time this variant is installed. If set to @code{#f}, hooks
27564 in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
27565 @item @code{proxy} (default: @code{#f})
27566 Optional HTTP proxy to use.
27567 @item @code{mirror} (default: @code{#f})
27568 The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
27569 The default varies depending on the distribution.
27570 @item @code{arch} (default: @code{#f})
27571 The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
27572 on an AArch64 host. Default is to use the current system architecture.
27573 @item @code{suite} (default: @code{"stable"})
27574 When set, this must be a Debian distribution ``suite'' such as @code{buster}
27575 or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
27576 @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
27577 List of extra packages that will get installed by dpkg in addition
27578 to the minimal system.
27579 @item @code{components} (default: @code{#f})
27580 When set, must be a list of Debian repository ``components''. For example
27581 @code{'("main" "contrib")}.
27582 @item @code{generate-cache?} (default: @code{#t})
27583 Whether to automatically cache the generated debootstrap archive.
27584 @item @code{clean-cache} (default: @code{14})
27585 Discard the cache after this amount of days. Use @code{#f} to never
27587 @item @code{partition-style} (default: @code{'msdos})
27588 The type of partition to create. When set, it must be one of
27589 @code{'msdos}, @code{'none} or a string.
27590 @item @code{partition-alignment} (default: @code{2048})
27591 Alignment of the partition in sectors.
27595 @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
27596 This is a helper procedure that creates a @code{ganeti-os-variant} record. It
27597 takes two parameters: a name and a @code{debootstrap-configuration} object.
27600 @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
27601 This is a helper procedure that creates a @code{ganeti-os} record. It takes
27602 a list of variants created with @code{debootstrap-variant}.
27605 @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
27606 This is a helper procedure that creates a @code{ganeti-os-variant} record for
27607 use with the Guix OS provider. It takes a name and a G-expression that returns
27608 a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
27609 Guix System configuration.
27612 @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
27613 This is a helper procedure that creates a @code{ganeti-os} record. It
27614 takes a list of variants produced by @code{guix-variant}.
27617 @defvr {Scheme Variable} %default-debootstrap-variants
27618 This is a convenience variable to make the debootstrap provider work
27619 ``out of the box'' without users having to declare variants manually. It
27620 contains a single debootstrap variant with the default configuration:
27623 (list (debootstrap-variant
27625 (debootstrap-configuration)))
27629 @defvr {Scheme Variable} %default-guix-variants
27630 This is a convenience variable to make the Guix OS provider work without
27631 additional configuration. It creates a virtual machine that has an SSH
27632 server, a serial console, and authorizes the Ganeti hosts SSH keys.
27635 (list (guix-variant
27637 (file-append ganeti-instance-guix
27638 "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
27642 Users can implement support for OS providers unbeknownst to Guix by extending
27643 the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
27649 (extension ".conf")
27651 (list (ganeti-os-variant
27653 (configuration (plain-file "bar" "this is fine"))))))
27656 That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
27657 to a file in the store with contents @code{this is fine}. It also creates
27658 @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
27660 Obviously this may not work for all OS providers out there. If you find the
27661 interface limiting, please reach out to @email{guix-devel@@gnu.org}.
27663 The rest of this section documents the various services that are included by
27664 @code{ganeti-service-type}.
27666 @defvr {Scheme Variable} ganeti-noded-service-type
27667 @command{ganeti-noded} is the daemon responsible for node-specific functions
27668 within the Ganeti system. The value of this service must be a
27669 @code{ganeti-noded-configuration} object.
27672 @deftp {Data Type} ganeti-noded-configuration
27673 This is the configuration for the @code{ganeti-noded} service.
27676 @item @code{ganeti} (default: @code{ganeti})
27677 The @code{ganeti} package to use for this service.
27679 @item @code{port} (default: @code{1811})
27680 The TCP port on which the node daemon listens for network requests.
27682 @item @code{address} (default: @code{"0.0.0.0"})
27683 The network address that the daemon will bind to. The default address means
27684 bind to all available addresses.
27686 @item @code{interface} (default: @code{#f})
27687 When this is set, it must be a specific network interface (e.g.@: @code{eth0})
27688 that the daemon will bind to.
27690 @item @code{max-clients} (default: @code{20})
27691 This sets a limit on the maximum number of simultaneous client connections
27692 that the daemon will handle. Connections above this count are accepted, but
27693 no responses will be sent until enough connections have closed.
27695 @item @code{ssl?} (default: @code{#t})
27696 Whether to use SSL/TLS to encrypt network communications. The certificate
27697 is automatically provisioned by the cluster and can be rotated with
27698 @command{gnt-cluster renew-crypto}.
27700 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
27701 This can be used to provide a specific encryption key for TLS communications.
27703 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
27704 This can be used to provide a specific certificate for TLS communications.
27706 @item @code{debug?} (default: @code{#f})
27707 When true, the daemon performs additional logging for debugging purposes.
27708 Note that this will leak encryption details to the log files, use with caution.
27713 @defvr {Scheme Variable} ganeti-confd-service-type
27714 @command{ganeti-confd} answers queries related to the configuration of a
27715 Ganeti cluster. The purpose of this daemon is to have a highly available
27716 and fast way to query cluster configuration values. It is automatically
27717 active on all @dfn{master candidates}. The value of this service must be a
27718 @code{ganeti-confd-configuration} object.
27722 @deftp {Data Type} ganeti-confd-configuration
27723 This is the configuration for the @code{ganeti-confd} service.
27726 @item @code{ganeti} (default: @code{ganeti})
27727 The @code{ganeti} package to use for this service.
27729 @item @code{port} (default: @code{1814})
27730 The UDP port on which to listen for network requests.
27732 @item @code{address} (default: @code{"0.0.0.0"})
27733 Network address that the daemon will bind to.
27735 @item @code{debug?} (default: @code{#f})
27736 When true, the daemon performs additional logging for debugging purposes.
27741 @defvr {Scheme Variable} ganeti-wconfd-service-type
27742 @command{ganeti-wconfd} is the daemon that has authoritative knowledge
27743 about the cluster configuration and is the only entity that can accept
27744 changes to it. All jobs that need to modify the configuration will do so
27745 by sending appropriate requests to this daemon. It only runs on the
27746 @dfn{master node} and will automatically disable itself on other nodes.
27748 The value of this service must be a
27749 @code{ganeti-wconfd-configuration} object.
27752 @deftp {Data Type} ganeti-wconfd-configuration
27753 This is the configuration for the @code{ganeti-wconfd} service.
27756 @item @code{ganeti} (default: @code{ganeti})
27757 The @code{ganeti} package to use for this service.
27759 @item @code{no-voting?} (default: @code{#f})
27760 The daemon will refuse to start if the majority of cluster nodes does not
27761 agree that it is running on the master node. Set to @code{#t} to start
27762 even if a quorum can not be reached (dangerous, use with caution).
27764 @item @code{debug?} (default: @code{#f})
27765 When true, the daemon performs additional logging for debugging purposes.
27770 @defvr {Scheme Variable} ganeti-luxid-service-type
27771 @command{ganeti-luxid} is a daemon used to answer queries related to the
27772 configuration and the current live state of a Ganeti cluster. Additionally,
27773 it is the authoritative daemon for the Ganeti job queue. Jobs can be
27774 submitted via this daemon and it schedules and starts them.
27776 It takes a @code{ganeti-luxid-configuration} object.
27779 @deftp {Data Type} ganeti-luxid-configuration
27780 This is the configuration for the @code{ganeti-wconfd} service.
27783 @item @code{ganeti} (default: @code{ganeti})
27784 The @code{ganeti} package to use for this service.
27786 @item @code{no-voting?} (default: @code{#f})
27787 The daemon will refuse to start if it cannot verify that the majority of
27788 cluster nodes believes that it is running on the master node. Set to
27789 @code{#t} to ignore such checks and start anyway (this can be dangerous).
27791 @item @code{debug?} (default: @code{#f})
27792 When true, the daemon performs additional logging for debugging purposes.
27797 @defvr {Scheme Variable} ganeti-rapi-service-type
27798 @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
27799 the master node and can be used to perform cluster actions programmatically
27800 via a JSON-based RPC protocol.
27802 Most query operations are allowed without authentication (unless
27803 @var{require-authentication?} is set), whereas write operations require
27804 explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
27805 the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
27806 API documentation} for more information.
27808 The value of this service must be a @code{ganeti-rapi-configuration} object.
27811 @deftp {Data Type} ganeti-rapi-configuration
27812 This is the configuration for the @code{ganeti-rapi} service.
27815 @item @code{ganeti} (default: @code{ganeti})
27816 The @code{ganeti} package to use for this service.
27818 @item @code{require-authentication?} (default: @code{#f})
27819 Whether to require authentication even for read-only operations.
27821 @item @code{port} (default: @code{5080})
27822 The TCP port on which to listen to API requests.
27824 @item @code{address} (default: @code{"0.0.0.0"})
27825 The network address that the service will bind to. By default it listens
27826 on all configured addresses.
27828 @item @code{interface} (default: @code{#f})
27829 When set, it must specify a specific network interface such as @code{eth0}
27830 that the daemon will bind to.
27832 @item @code{max-clients} (default: @code{20})
27833 The maximum number of simultaneous client requests to handle. Further
27834 connections are allowed, but no responses are sent until enough connections
27837 @item @code{ssl?} (default: @code{#t})
27838 Whether to use SSL/TLS encryption on the RAPI port.
27840 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
27841 This can be used to provide a specific encryption key for TLS communications.
27843 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
27844 This can be used to provide a specific certificate for TLS communications.
27846 @item @code{debug?} (default: @code{#f})
27847 When true, the daemon performs additional logging for debugging purposes.
27848 Note that this will leak encryption details to the log files, use with caution.
27853 @defvr {Scheme Variable} ganeti-kvmd-service-type
27854 @command{ganeti-kvmd} is responsible for determining whether a given KVM
27855 instance was shut down by an administrator or a user. Normally Ganeti will
27856 restart an instance that was not stopped through Ganeti itself. If the
27857 cluster option @code{user_shutdown} is true, this daemon monitors the
27858 @code{QMP} socket provided by QEMU and listens for shutdown events, and
27859 marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
27860 it shuts down gracefully by itself.
27862 It takes a @code{ganeti-kvmd-configuration} object.
27865 @deftp {Data Type} ganeti-kvmd-configuration
27868 @item @code{ganeti} (default: @code{ganeti})
27869 The @code{ganeti} package to use for this service.
27871 @item @code{debug?} (default: @code{#f})
27872 When true, the daemon performs additional logging for debugging purposes.
27877 @defvr {Scheme Variable} ganeti-mond-service-type
27878 @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
27879 functionality. It is responsible for running data collectors and publish the
27880 collected information through a HTTP interface.
27882 It takes a @code{ganeti-mond-configuration} object.
27885 @deftp {Data Type} ganeti-mond-configuration
27888 @item @code{ganeti} (default: @code{ganeti})
27889 The @code{ganeti} package to use for this service.
27891 @item @code{port} (default: @code{1815})
27892 The port on which the daemon will listen.
27894 @item @code{address} (default: @code{"0.0.0.0"})
27895 The network address that the daemon will bind to. By default it binds to all
27896 available interfaces.
27898 @item @code{debug?} (default: @code{#f})
27899 When true, the daemon performs additional logging for debugging purposes.
27904 @defvr {Scheme Variable} ganeti-metad-service-type
27905 @command{ganeti-metad} is an optional daemon that can be used to provide
27906 information about the cluster to instances or OS install scripts.
27908 It takes a @code{ganeti-metad-configuration} object.
27911 @deftp {Data Type} ganeti-metad-configuration
27914 @item @code{ganeti} (default: @code{ganeti})
27915 The @code{ganeti} package to use for this service.
27917 @item @code{port} (default: @code{80})
27918 The port on which the daemon will listen.
27920 @item @code{address} (default: @code{#f})
27921 If set, the daemon will bind to this address only. If left unset, the behavior
27922 depends on the cluster configuration.
27924 @item @code{debug?} (default: @code{#f})
27925 When true, the daemon performs additional logging for debugging purposes.
27930 @defvr {Scheme Variable} ganeti-watcher-service-type
27931 @command{ganeti-watcher} is a script designed to run periodically and ensure
27932 the health of a cluster. It will automatically restart instances that have
27933 stopped without Ganeti's consent, and repairs DRBD links in case a node has
27934 rebooted. It also archives old cluster jobs and restarts Ganeti daemons
27935 that are not running. If the cluster parameter @code{ensure_node_health}
27936 is set, the watcher will also shutdown instances and DRBD devices if the
27937 node it is running on is declared offline by known master candidates.
27939 It can be paused on all nodes with @command{gnt-cluster watcher pause}.
27941 The service takes a @code{ganeti-watcher-configuration} object.
27944 @deftp {Data Type} ganeti-watcher-configuration
27947 @item @code{ganeti} (default: @code{ganeti})
27948 The @code{ganeti} package to use for this service.
27950 @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
27951 How often to run the script. The default is every five minutes.
27953 @item @code{rapi-ip} (default: @code{#f})
27954 This option needs to be specified only if the RAPI daemon is configured to use
27955 a particular interface or address. By default the cluster address is used.
27957 @item @code{job-age} (default: @code{(* 6 3600)})
27958 Archive cluster jobs older than this age, specified in seconds. The default
27959 is 6 hours. This keeps @command{gnt-job list} manageable.
27961 @item @code{verify-disks?} (default: @code{#t})
27962 If this is @code{#f}, the watcher will not try to repair broken DRBD links
27963 automatically. Administrators will need to use @command{gnt-cluster verify-disks}
27966 @item @code{debug?} (default: @code{#f})
27967 When @code{#t}, the script performs additional logging for debugging purposes.
27972 @defvr {Scheme Variable} ganeti-cleaner-service-type
27973 @command{ganeti-cleaner} is a script designed to run periodically and remove
27974 old files from the cluster. This service type controls two @dfn{cron jobs}:
27975 one intended for the master node that permanently purges old cluster jobs,
27976 and one intended for every node that removes expired X509 certificates, keys,
27977 and outdated @command{ganeti-watcher} information. Like all Ganeti services,
27978 it is safe to include even on non-master nodes as it will disable itself as
27981 It takes a @code{ganeti-cleaner-configuration} object.
27984 @deftp {Data Type} ganeti-cleaner-configuration
27987 @item @code{ganeti} (default: @code{ganeti})
27988 The @code{ganeti} package to use for the @command{gnt-cleaner} command.
27990 @item @code{master-schedule} (default: @code{"45 1 * * *"})
27991 How often to run the master cleaning job. The default is once per day, at
27994 @item @code{node-schedule} (default: @code{"45 2 * * *"})
27995 How often to run the node cleaning job. The default is once per day, at
28001 @node Version Control Services
28002 @subsection Version Control Services
28004 The @code{(gnu services version-control)} module provides a service to
28005 allow remote access to local Git repositories. There are three options:
28006 the @code{git-daemon-service}, which provides access to repositories via
28007 the @code{git://} unsecured TCP-based protocol, extending the
28008 @code{nginx} web server to proxy some requests to
28009 @code{git-http-backend}, or providing a web interface with
28010 @code{cgit-service-type}.
28012 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
28014 Return a service that runs @command{git daemon}, a simple TCP server to
28015 expose repositories over the Git protocol for anonymous access.
28017 The optional @var{config} argument should be a
28018 @code{<git-daemon-configuration>} object, by default it allows read-only
28019 access to exported@footnote{By creating the magic file
28020 @file{git-daemon-export-ok} in the repository directory.} repositories under
28025 @deftp {Data Type} git-daemon-configuration
28026 Data type representing the configuration for @code{git-daemon-service}.
28029 @item @code{package} (default: @code{git})
28030 Package object of the Git distributed version control system.
28032 @item @code{export-all?} (default: @code{#f})
28033 Whether to allow access for all Git repositories, even if they do not
28034 have the @file{git-daemon-export-ok} file.
28036 @item @code{base-path} (default: @file{/srv/git})
28037 Whether to remap all the path requests as relative to the given path.
28038 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
28039 @samp{example.com}, then if you later try to pull
28040 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
28041 path as @file{/srv/git/hello.git}.
28043 @item @code{user-path} (default: @code{#f})
28044 Whether to allow @code{~user} notation to be used in requests. When
28045 specified with empty string, requests to
28046 @indicateurl{git://host/~alice/foo} is taken as a request to access
28047 @code{foo} repository in the home directory of user @code{alice}. If
28048 @code{(user-path "@var{path}")} is specified, the same request is taken
28049 as a request to access @file{@var{path}/foo} repository in the home
28050 directory of user @code{alice}.
28052 @item @code{listen} (default: @code{'()})
28053 Whether to listen on specific IP addresses or hostnames, defaults to
28056 @item @code{port} (default: @code{#f})
28057 Whether to listen on an alternative port, which defaults to 9418.
28059 @item @code{whitelist} (default: @code{'()})
28060 If not empty, only allow access to this list of directories.
28062 @item @code{extra-options} (default: @code{'()})
28063 Extra options will be passed to @command{git daemon}, please run
28064 @command{man git-daemon} for more information.
28069 The @code{git://} protocol lacks authentication. When you pull from a
28070 repository fetched via @code{git://}, you don't know whether the data you
28071 receive was modified or is even coming from the specified host, and your
28072 connection is subject to eavesdropping. It's better to use an authenticated
28073 and encrypted transport, such as @code{https}. Although Git allows you
28074 to serve repositories using unsophisticated file-based web servers,
28075 there is a faster protocol implemented by the @code{git-http-backend}
28076 program. This program is the back-end of a proper Git web service. It
28077 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
28078 on running the necessary @code{fcgiwrap} daemon.
28080 Guix has a separate configuration data type for serving Git repositories
28083 @deftp {Data Type} git-http-configuration
28084 Data type representing the configuration for a future
28085 @code{git-http-service-type}; can currently be used to configure Nginx
28086 through @code{git-http-nginx-location-configuration}.
28089 @item @code{package} (default: @var{git})
28090 Package object of the Git distributed version control system.
28092 @item @code{git-root} (default: @file{/srv/git})
28093 Directory containing the Git repositories to expose to the world.
28095 @item @code{export-all?} (default: @code{#f})
28096 Whether to expose access for all Git repositories in @var{git-root},
28097 even if they do not have the @file{git-daemon-export-ok} file.
28099 @item @code{uri-path} (default: @samp{/git/})
28100 Path prefix for Git access. With the default @samp{/git/} prefix, this
28101 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
28102 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
28103 with this prefix are not passed on to this Git instance.
28105 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
28106 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
28111 There is no @code{git-http-service-type}, currently; instead you can
28112 create an @code{nginx-location-configuration} from a
28113 @code{git-http-configuration} and then add that location to a web
28116 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
28117 [config=(git-http-configuration)]
28118 Compute an @code{nginx-location-configuration} that corresponds to the
28119 given Git http configuration. An example nginx service definition to
28120 serve the default @file{/srv/git} over HTTPS might be:
28123 (service nginx-service-type
28124 (nginx-configuration
28127 (nginx-server-configuration
28128 (listen '("443 ssl"))
28129 (server-name "git.my-host.org")
28131 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
28132 (ssl-certificate-key
28133 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
28136 (git-http-nginx-location-configuration
28137 (git-http-configuration (uri-path "/"))))))))))
28140 This example assumes that you are using Let's Encrypt to get your TLS
28141 certificate. @xref{Certificate Services}. The default @code{certbot}
28142 service will redirect all HTTP traffic on @code{git.my-host.org} to
28143 HTTPS. You will also need to add an @code{fcgiwrap} proxy to your
28144 system services. @xref{Web Services}.
28147 @subsubheading Cgit Service
28149 @cindex Cgit service
28150 @cindex Git, web interface
28151 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
28152 repositories written in C.
28154 The following example will configure the service with default values.
28155 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
28158 (service cgit-service-type)
28161 The @code{file-object} type designates either a file-like object
28162 (@pxref{G-Expressions, file-like objects}) or a string.
28164 @c %start of fragment
28166 Available @code{cgit-configuration} fields are:
28168 @deftypevr {@code{cgit-configuration} parameter} package package
28173 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
28174 NGINX configuration.
28178 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
28179 Specifies a command which will be invoked to format the content of about
28180 pages (both top-level and for each repository).
28182 Defaults to @samp{""}.
28186 @deftypevr {@code{cgit-configuration} parameter} string agefile
28187 Specifies a path, relative to each repository path, which can be used to
28188 specify the date and time of the youngest commit in the repository.
28190 Defaults to @samp{""}.
28194 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
28195 Specifies a command that will be invoked for authenticating repository
28198 Defaults to @samp{""}.
28202 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
28203 Flag which, when set to @samp{age}, enables date ordering in the branch
28204 ref list, and when set @samp{name} enables ordering by branch name.
28206 Defaults to @samp{"name"}.
28210 @deftypevr {@code{cgit-configuration} parameter} string cache-root
28211 Path used to store the cgit cache entries.
28213 Defaults to @samp{"/var/cache/cgit"}.
28217 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
28218 Number which specifies the time-to-live, in minutes, for the cached
28219 version of repository pages accessed with a fixed SHA1.
28221 Defaults to @samp{-1}.
28225 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
28226 Number which specifies the time-to-live, in minutes, for the cached
28227 version of repository pages accessed without a fixed SHA1.
28229 Defaults to @samp{5}.
28233 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
28234 Number which specifies the time-to-live, in minutes, for the cached
28235 version of the repository summary page.
28237 Defaults to @samp{5}.
28241 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
28242 Number which specifies the time-to-live, in minutes, for the cached
28243 version of the repository index page.
28245 Defaults to @samp{5}.
28249 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
28250 Number which specifies the time-to-live, in minutes, for the result of
28251 scanning a path for Git repositories.
28253 Defaults to @samp{15}.
28257 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
28258 Number which specifies the time-to-live, in minutes, for the cached
28259 version of the repository about page.
28261 Defaults to @samp{15}.
28265 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
28266 Number which specifies the time-to-live, in minutes, for the cached
28267 version of snapshots.
28269 Defaults to @samp{5}.
28273 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
28274 The maximum number of entries in the cgit cache. When set to @samp{0},
28275 caching is disabled.
28277 Defaults to @samp{0}.
28281 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
28282 Sort items in the repo list case sensitively.
28284 Defaults to @samp{#t}.
28288 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
28289 List of common prefixes which, when combined with a repository URL,
28290 generates valid clone URLs for the repository.
28292 Defaults to @samp{()}.
28296 @deftypevr {@code{cgit-configuration} parameter} list clone-url
28297 List of @code{clone-url} templates.
28299 Defaults to @samp{()}.
28303 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
28304 Command which will be invoked to format commit messages.
28306 Defaults to @samp{""}.
28310 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
28311 Flag which, when set to @samp{date}, enables strict date ordering in the
28312 commit log, and when set to @samp{topo} enables strict topological
28315 Defaults to @samp{"git log"}.
28319 @deftypevr {@code{cgit-configuration} parameter} file-object css
28320 URL which specifies the css document to include in all cgit pages.
28322 Defaults to @samp{"/share/cgit/cgit.css"}.
28326 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
28327 Specifies a command which will be invoked to format names and email
28328 address of committers, authors, and taggers, as represented in various
28329 places throughout the cgit interface.
28331 Defaults to @samp{""}.
28335 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
28336 Flag which, when set to @samp{#t}, will make cgit generate a HTML
28337 fragment suitable for embedding in other HTML pages.
28339 Defaults to @samp{#f}.
28343 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
28344 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
28345 commit history graph to the left of the commit messages in the
28346 repository log page.
28348 Defaults to @samp{#f}.
28352 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
28353 Flag which, when set to @samp{#t}, allows all filter settings to be
28354 overridden in repository-specific cgitrc files.
28356 Defaults to @samp{#f}.
28360 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
28361 Flag which, when set to @samp{#t}, allows users to follow a file in the
28364 Defaults to @samp{#f}.
28368 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
28369 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
28372 Defaults to @samp{#t}.
28376 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
28377 Flag which, when set to @samp{#t}, will make cgit generate extra links
28378 "summary", "commit", "tree" for each repo in the repository index.
28380 Defaults to @samp{#f}.
28384 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
28385 Flag which, when set to @samp{#t}, will make cgit display the owner of
28386 each repo in the repository index.
28388 Defaults to @samp{#t}.
28392 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
28393 Flag which, when set to @samp{#t}, will make cgit print the number of
28394 modified files for each commit on the repository log page.
28396 Defaults to @samp{#f}.
28400 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
28401 Flag which, when set to @samp{#t}, will make cgit print the number of
28402 added and removed lines for each commit on the repository log page.
28404 Defaults to @samp{#f}.
28408 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
28409 Flag which, when set to @code{#t}, will make cgit display remote
28410 branches in the summary and refs views.
28412 Defaults to @samp{#f}.
28416 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
28417 Flag which, when set to @code{1}, will make cgit use the subject of the
28418 parent commit as link text when generating links to parent commits in
28421 Defaults to @samp{#f}.
28425 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
28426 Flag which, when set to @samp{#t}, will make cgit use the subject of the
28427 parent commit as link text when generating links to parent commits in
28430 Defaults to @samp{#f}.
28434 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
28435 Flag which, when set to @samp{#t}, will make cgit generate linenumber
28436 links for plaintext blobs printed in the tree view.
28438 Defaults to @samp{#t}.
28442 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
28443 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
28444 set any repo specific settings.
28446 Defaults to @samp{#f}.
28450 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
28451 URL used as link to a shortcut icon for cgit.
28453 Defaults to @samp{"/favicon.ico"}.
28457 @deftypevr {@code{cgit-configuration} parameter} string footer
28458 The content of the file specified with this option will be included
28459 verbatim at the bottom of all pages (i.e.@: it replaces the standard
28460 "generated by..."@: message).
28462 Defaults to @samp{""}.
28466 @deftypevr {@code{cgit-configuration} parameter} string head-include
28467 The content of the file specified with this option will be included
28468 verbatim in the HTML HEAD section on all pages.
28470 Defaults to @samp{""}.
28474 @deftypevr {@code{cgit-configuration} parameter} string header
28475 The content of the file specified with this option will be included
28476 verbatim at the top of all pages.
28478 Defaults to @samp{""}.
28482 @deftypevr {@code{cgit-configuration} parameter} file-object include
28483 Name of a configfile to include before the rest of the current config-
28486 Defaults to @samp{""}.
28490 @deftypevr {@code{cgit-configuration} parameter} string index-header
28491 The content of the file specified with this option will be included
28492 verbatim above the repository index.
28494 Defaults to @samp{""}.
28498 @deftypevr {@code{cgit-configuration} parameter} string index-info
28499 The content of the file specified with this option will be included
28500 verbatim below the heading on the repository index page.
28502 Defaults to @samp{""}.
28506 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
28507 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
28508 in the servers timezone.
28510 Defaults to @samp{#f}.
28514 @deftypevr {@code{cgit-configuration} parameter} file-object logo
28515 URL which specifies the source of an image which will be used as a logo
28518 Defaults to @samp{"/share/cgit/cgit.png"}.
28522 @deftypevr {@code{cgit-configuration} parameter} string logo-link
28523 URL loaded when clicking on the cgit logo image.
28525 Defaults to @samp{""}.
28529 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
28530 Command which will be invoked to format the Owner column of the main
28533 Defaults to @samp{""}.
28537 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
28538 Number of items to display in atom feeds view.
28540 Defaults to @samp{10}.
28544 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
28545 Number of entries to list per page in "log" view.
28547 Defaults to @samp{50}.
28551 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
28552 Number of commit message characters to display in "log" view.
28554 Defaults to @samp{80}.
28558 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
28559 Specifies the number of entries to list per page on the repository index
28562 Defaults to @samp{50}.
28566 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
28567 Specifies the maximum number of repo description characters to display
28568 on the repository index page.
28570 Defaults to @samp{80}.
28574 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
28575 Specifies the maximum size of a blob to display HTML for in KBytes.
28577 Defaults to @samp{0}.
28581 @deftypevr {@code{cgit-configuration} parameter} string max-stats
28582 Maximum statistics period. Valid values are @samp{week},@samp{month},
28583 @samp{quarter} and @samp{year}.
28585 Defaults to @samp{""}.
28589 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
28590 Mimetype for the specified filename extension.
28592 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
28593 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
28594 "image/png") (svg "image/svg+xml"))}.
28598 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
28599 Specifies the file to use for automatic mimetype lookup.
28601 Defaults to @samp{""}.
28605 @deftypevr {@code{cgit-configuration} parameter} string module-link
28606 Text which will be used as the formatstring for a hyperlink when a
28607 submodule is printed in a directory listing.
28609 Defaults to @samp{""}.
28613 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
28614 If set to the value @samp{#t} caching will be disabled.
28616 Defaults to @samp{#f}.
28620 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
28621 If set to @samp{#t} showing full author email addresses will be
28624 Defaults to @samp{#f}.
28628 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
28629 Flag which, when set to @samp{#t}, will make cgit omit the standard
28630 header on all pages.
28632 Defaults to @samp{#f}.
28636 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
28637 A list of subdirectories inside of @code{repository-directory}, relative
28638 to it, that should loaded as Git repositories. An empty list means that
28639 all subdirectories will be loaded.
28641 Defaults to @samp{()}.
28645 @deftypevr {@code{cgit-configuration} parameter} file-object readme
28646 Text which will be used as default value for @code{cgit-repo-readme}.
28648 Defaults to @samp{""}.
28652 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
28653 If set to @code{#t} and @code{repository-directory} is enabled, if any
28654 repositories are found with a suffix of @code{.git}, this suffix will be
28655 removed for the URL and name.
28657 Defaults to @samp{#f}.
28661 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
28662 Maximum number of files to consider when detecting renames.
28664 Defaults to @samp{-1}.
28668 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
28669 The way in which repositories in each section are sorted.
28671 Defaults to @samp{""}.
28675 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
28676 Text used as content for the @code{robots} meta-tag.
28678 Defaults to @samp{("noindex" "nofollow")}.
28682 @deftypevr {@code{cgit-configuration} parameter} string root-desc
28683 Text printed below the heading on the repository index page.
28685 Defaults to @samp{"a fast webinterface for the git dscm"}.
28689 @deftypevr {@code{cgit-configuration} parameter} string root-readme
28690 The content of the file specified with this option will be included
28691 verbatim below the ``about'' link on the repository index page.
28693 Defaults to @samp{""}.
28697 @deftypevr {@code{cgit-configuration} parameter} string root-title
28698 Text printed as heading on the repository index page.
28700 Defaults to @samp{""}.
28704 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
28705 If set to @samp{#t} and repository-directory is enabled,
28706 repository-directory will recurse into directories whose name starts
28707 with a period. Otherwise, repository-directory will stay away from such
28708 directories, considered as ``hidden''. Note that this does not apply to
28709 the @file{.git} directory in non-bare repos.
28711 Defaults to @samp{#f}.
28715 @deftypevr {@code{cgit-configuration} parameter} list snapshots
28716 Text which specifies the default set of snapshot formats that cgit
28717 generates links for.
28719 Defaults to @samp{()}.
28723 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
28724 Name of the directory to scan for repositories (represents
28727 Defaults to @samp{"/srv/git"}.
28731 @deftypevr {@code{cgit-configuration} parameter} string section
28732 The name of the current repository section - all repositories defined
28733 after this option will inherit the current section name.
28735 Defaults to @samp{""}.
28739 @deftypevr {@code{cgit-configuration} parameter} string section-sort
28740 Flag which, when set to @samp{1}, will sort the sections on the
28741 repository listing by name.
28743 Defaults to @samp{""}.
28747 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
28748 A number which, if defined prior to repository-directory, specifies how
28749 many path elements from each repo path to use as a default section name.
28751 Defaults to @samp{0}.
28755 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
28756 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
28759 Defaults to @samp{#f}.
28763 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
28764 Specifies a command which will be invoked to format plaintext blobs in
28767 Defaults to @samp{""}.
28771 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
28772 Specifies the number of branches to display in the repository ``summary''
28775 Defaults to @samp{10}.
28779 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
28780 Specifies the number of log entries to display in the repository
28783 Defaults to @samp{10}.
28787 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
28788 Specifies the number of tags to display in the repository ``summary''
28791 Defaults to @samp{10}.
28795 @deftypevr {@code{cgit-configuration} parameter} string strict-export
28796 Filename which, if specified, needs to be present within the repository
28797 for cgit to allow access to that repository.
28799 Defaults to @samp{""}.
28803 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
28804 URL which, if specified, will be used as root for all cgit links.
28806 Defaults to @samp{"/"}.
28810 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
28811 A list of @dfn{cgit-repo} records to use with config.
28813 Defaults to @samp{()}.
28815 Available @code{repository-cgit-configuration} fields are:
28817 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
28818 A mask of snapshot formats for this repo that cgit generates links for,
28819 restricted by the global @code{snapshots} setting.
28821 Defaults to @samp{()}.
28825 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
28826 Override the default @code{source-filter}.
28828 Defaults to @samp{""}.
28832 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
28833 The relative URL used to access the repository.
28835 Defaults to @samp{""}.
28839 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
28840 Override the default @code{about-filter}.
28842 Defaults to @samp{""}.
28846 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
28847 Flag which, when set to @samp{age}, enables date ordering in the branch
28848 ref list, and when set to @samp{name} enables ordering by branch name.
28850 Defaults to @samp{""}.
28854 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
28855 A list of URLs which can be used to clone repo.
28857 Defaults to @samp{()}.
28861 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
28862 Override the default @code{commit-filter}.
28864 Defaults to @samp{""}.
28868 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
28869 Flag which, when set to @samp{date}, enables strict date ordering in the
28870 commit log, and when set to @samp{topo} enables strict topological
28873 Defaults to @samp{""}.
28877 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
28878 The name of the default branch for this repository. If no such branch
28879 exists in the repository, the first branch name (when sorted) is used as
28880 default instead. By default branch pointed to by HEAD, or ``master'' if
28881 there is no suitable HEAD.
28883 Defaults to @samp{""}.
28887 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
28888 The value to show as repository description.
28890 Defaults to @samp{""}.
28894 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
28895 The value to show as repository homepage.
28897 Defaults to @samp{""}.
28901 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
28902 Override the default @code{email-filter}.
28904 Defaults to @samp{""}.
28908 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
28909 A flag which can be used to disable the global setting
28910 @code{enable-commit-graph?}.
28912 Defaults to @samp{disabled}.
28916 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
28917 A flag which can be used to disable the global setting
28918 @code{enable-log-filecount?}.
28920 Defaults to @samp{disabled}.
28924 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
28925 A flag which can be used to disable the global setting
28926 @code{enable-log-linecount?}.
28928 Defaults to @samp{disabled}.
28932 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
28933 Flag which, when set to @code{#t}, will make cgit display remote
28934 branches in the summary and refs views.
28936 Defaults to @samp{disabled}.
28940 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
28941 A flag which can be used to override the global setting
28942 @code{enable-subject-links?}.
28944 Defaults to @samp{disabled}.
28948 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
28949 A flag which can be used to override the global setting
28950 @code{enable-html-serving?}.
28952 Defaults to @samp{disabled}.
28956 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
28957 Flag which, when set to @code{#t}, hides the repository from the
28960 Defaults to @samp{#f}.
28964 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
28965 Flag which, when set to @samp{#t}, ignores the repository.
28967 Defaults to @samp{#f}.
28971 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
28972 URL which specifies the source of an image which will be used as a logo
28973 on this repo’s pages.
28975 Defaults to @samp{""}.
28979 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
28980 URL loaded when clicking on the cgit logo image.
28982 Defaults to @samp{""}.
28986 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
28987 Override the default @code{owner-filter}.
28989 Defaults to @samp{""}.
28993 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
28994 Text which will be used as the formatstring for a hyperlink when a
28995 submodule is printed in a directory listing. The arguments for the
28996 formatstring are the path and SHA1 of the submodule commit.
28998 Defaults to @samp{""}.
29002 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
29003 Text which will be used as the formatstring for a hyperlink when a
29004 submodule with the specified subdirectory path is printed in a directory
29007 Defaults to @samp{()}.
29011 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
29012 Override the default maximum statistics period.
29014 Defaults to @samp{""}.
29018 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
29019 The value to show as repository name.
29021 Defaults to @samp{""}.
29025 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
29026 A value used to identify the owner of the repository.
29028 Defaults to @samp{""}.
29032 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
29033 An absolute path to the repository directory.
29035 Defaults to @samp{""}.
29039 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
29040 A path (relative to repo) which specifies a file to include verbatim as
29041 the ``About'' page for this repo.
29043 Defaults to @samp{""}.
29047 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
29048 The name of the current repository section - all repositories defined
29049 after this option will inherit the current section name.
29051 Defaults to @samp{""}.
29055 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
29056 Extra options will be appended to cgitrc file.
29058 Defaults to @samp{()}.
29064 @deftypevr {@code{cgit-configuration} parameter} list extra-options
29065 Extra options will be appended to cgitrc file.
29067 Defaults to @samp{()}.
29072 @c %end of fragment
29074 However, it could be that you just want to get a @code{cgitrc} up and
29075 running. In that case, you can pass an @code{opaque-cgit-configuration}
29076 as a record to @code{cgit-service-type}. As its name indicates, an
29077 opaque configuration does not have easy reflective capabilities.
29079 Available @code{opaque-cgit-configuration} fields are:
29081 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
29085 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
29086 The contents of the @code{cgitrc}, as a string.
29089 For example, if your @code{cgitrc} is just the empty string, you
29090 could instantiate a cgit service like this:
29093 (service cgit-service-type
29094 (opaque-cgit-configuration
29098 @subsubheading Gitolite Service
29100 @cindex Gitolite service
29101 @cindex Git, hosting
29102 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
29103 repositories on a central server.
29105 Gitolite can handle multiple repositories and users, and supports flexible
29106 configuration of the permissions for the users on the repositories.
29108 The following example will configure Gitolite using the default @code{git}
29109 user, and the provided SSH public key.
29112 (service gitolite-service-type
29113 (gitolite-configuration
29114 (admin-pubkey (plain-file
29116 "ssh-rsa AAAA... guix@@example.com"))))
29119 Gitolite is configured through a special admin repository which you can clone,
29120 for example, if you setup Gitolite on @code{example.com}, you would run the
29121 following command to clone the admin repository.
29124 git clone git@@example.com:gitolite-admin
29127 When the Gitolite service is activated, the provided @code{admin-pubkey} will
29128 be inserted in to the @file{keydir} directory in the gitolite-admin
29129 repository. If this results in a change in the repository, it will be
29130 committed using the message ``gitolite setup by GNU Guix''.
29132 @deftp {Data Type} gitolite-configuration
29133 Data type representing the configuration for @code{gitolite-service-type}.
29136 @item @code{package} (default: @var{gitolite})
29137 Gitolite package to use.
29139 @item @code{user} (default: @var{git})
29140 User to use for Gitolite. This will be user that you use when accessing
29143 @item @code{group} (default: @var{git})
29144 Group to use for Gitolite.
29146 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
29147 Directory in which to store the Gitolite configuration and repositories.
29149 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
29150 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
29151 representing the configuration for Gitolite.
29153 @item @code{admin-pubkey} (default: @var{#f})
29154 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
29155 setup Gitolite. This will be inserted in to the @file{keydir} directory
29156 within the gitolite-admin repository.
29158 To specify the SSH key as a string, use the @code{plain-file} function.
29161 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
29167 @deftp {Data Type} gitolite-rc-file
29168 Data type representing the Gitolite RC file.
29171 @item @code{umask} (default: @code{#o0077})
29172 This controls the permissions Gitolite sets on the repositories and their
29175 A value like @code{#o0027} will give read access to the group used by Gitolite
29176 (by default: @code{git}). This is necessary when using Gitolite with software
29177 like cgit or gitweb.
29179 @item @code{git-config-keys} (default: @code{""})
29180 Gitolite allows you to set git config values using the @samp{config} keyword. This
29181 setting allows control over the config keys to accept.
29183 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
29184 Set the role names allowed to be used by users running the perms command.
29186 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
29187 This setting controls the commands and features to enable within Gitolite.
29193 @node Game Services
29194 @subsection Game Services
29196 @subsubheading The Battle for Wesnoth Service
29198 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
29199 based tactical strategy game, with several single player campaigns, and
29200 multiplayer games (both networked and local).
29202 @defvar {Scheme Variable} wesnothd-service-type
29203 Service type for the wesnothd service. Its value must be a
29204 @code{wesnothd-configuration} object. To run wesnothd in the default
29205 configuration, instantiate it as:
29208 (service wesnothd-service-type)
29212 @deftp {Data Type} wesnothd-configuration
29213 Data type representing the configuration of @command{wesnothd}.
29216 @item @code{package} (default: @code{wesnoth-server})
29217 The wesnoth server package to use.
29219 @item @code{port} (default: @code{15000})
29220 The port to bind the server to.
29225 @node PAM Mount Service
29226 @subsection PAM Mount Service
29229 The @code{(gnu services pam-mount)} module provides a service allowing
29230 users to mount volumes when they log in. It should be able to mount any
29231 volume format supported by the system.
29233 @defvar {Scheme Variable} pam-mount-service-type
29234 Service type for PAM Mount support.
29237 @deftp {Data Type} pam-mount-configuration
29238 Data type representing the configuration of PAM Mount.
29240 It takes the following parameters:
29244 The configuration rules that will be used to generate
29245 @file{/etc/security/pam_mount.conf.xml}.
29247 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
29248 Guile Reference Manual}), and the default ones don't mount anything for
29252 `((debug (@@ (enable "0")))
29253 (mntoptions (@@ (allow ,(string-join
29254 '("nosuid" "nodev" "loop"
29255 "encryption" "fsck" "nonempty"
29256 "allow_root" "allow_other")
29258 (mntoptions (@@ (require "nosuid,nodev")))
29259 (logout (@@ (wait "0")
29263 (mkmountpoint (@@ (enable "1")
29267 Some @code{volume} elements must be added to automatically mount volumes
29268 at login. Here's an example allowing the user @code{alice} to mount her
29269 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
29270 the partition where he stores his data:
29273 (define pam-mount-rules
29274 `((debug (@@ (enable "0")))
29275 (volume (@@ (user "alice")
29278 (mountpoint "/home/alice")))
29279 (volume (@@ (user "bob")
29282 (mountpoint "/home/bob/data")
29283 (options "defaults,autodefrag,compress")))
29284 (mntoptions (@@ (allow ,(string-join
29285 '("nosuid" "nodev" "loop"
29286 "encryption" "fsck" "nonempty"
29287 "allow_root" "allow_other")
29289 (mntoptions (@@ (require "nosuid,nodev")))
29290 (logout (@@ (wait "0")
29294 (mkmountpoint (@@ (enable "1")
29295 (remove "true")))))
29297 (service pam-mount-service-type
29298 (pam-mount-configuration
29299 (rules pam-mount-rules)))
29302 The complete list of possible options can be found in the man page for
29303 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
29308 @node Guix Services
29309 @subsection Guix Services
29311 @subsubheading Guix Build Coordinator
29312 The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
29313 Coordinator} aids in distributing derivation builds among machines
29314 running an @dfn{agent}. The build daemon is still used to build the
29315 derivations, but the Guix Build Coordinator manages allocating builds
29316 and working with the results.
29319 This service is considered experimental. Configuration options may be
29320 changed in a backwards-incompatible manner, and not all features have
29321 been thorougly tested.
29324 The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
29325 more connected @dfn{agent} processes. The coordinator process handles
29326 clients submitting builds, and allocating builds to agents. The agent
29327 processes talk to a build daemon to actually perform the builds, then
29328 send the results back to the coordinator.
29330 There is a script to run the coordinator component of the Guix Build
29331 Coordinator, but the Guix service uses a custom Guile script instead, to
29332 provide better integration with G-expressions used in the configuration.
29334 @defvar {Scheme Variable} guix-build-coordinator-service-type
29335 Service type for the Guix Build Coordinator. Its value must be a
29336 @code{guix-build-coordinator-configuration} object.
29339 @deftp {Data Type} guix-build-coordinator-configuration
29340 Data type representing the configuration of the Guix Build Coordinator.
29343 @item @code{package} (default: @code{guix-build-coordinator})
29344 The Guix Build Coordinator package to use.
29346 @item @code{user} (default: @code{"guix-build-coordinator"})
29347 The system user to run the service as.
29349 @item @code{group} (default: @code{"guix-build-coordinator"})
29350 The system group to run the service as.
29352 @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
29353 The URI to use for the database.
29355 @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
29356 The URI describing how to listen to requests from agent processes.
29358 @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
29359 The URI describing how to listen to requests from clients. The client
29360 API allows submitting builds and currently isn't authenticated, so take
29361 care when configuring this value.
29363 @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
29364 A G-expression for the allocation strategy to be used. This is a
29365 procedure that takes the datastore as an argument and populates the
29366 allocation plan in the database.
29368 @item @code{hooks} (default: @var{'()})
29369 An association list of hooks. These provide a way to execute arbitrary
29370 code upon certain events, like a build result being processed.
29372 @item @code{guile} (default: @code{guile-3.0-latest})
29373 The Guile package with which to run the Guix Build Coordinator.
29378 @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
29379 Service type for a Guix Build Coordinator agent. Its value must be a
29380 @code{guix-build-coordinator-agent-configuration} object.
29383 @deftp {Data Type} guix-build-coordinator-agent-configuration
29384 Data type representing the configuration a Guix Build Coordinator agent.
29387 @item @code{package} (default: @code{guix-build-coordinator})
29388 The Guix Build Coordinator package to use.
29390 @item @code{user} (default: @code{"guix-build-coordinator-agent"})
29391 The system user to run the service as.
29393 @item @code{coordinator} (default: @code{"http://localhost:8745"})
29394 The URI to use when connecting to the coordinator.
29397 The UUID of the agent. This should be generated by the coordinator
29398 process, stored in the coordinator database, and used by the intended
29401 @item @code{password} (default: @code{#f})
29402 The password to use when connecting to the coordinator. A file to read
29403 the password from can also be specified, and this is more secure.
29405 @item @code{password-file} (default: @code{#f})
29406 A file containing the password to use when connecting to the
29409 @item @code{systems} (default: @code{#f})
29410 The systems for which this agent should fetch builds. The agent process
29411 will use the current system it's running on as the default.
29413 @item @code{max-parallel-builds} (default: @code{1})
29414 The number of builds to perform in parallel.
29416 @item @code{derivation-substitute-urls} (default: @code{#f})
29417 URLs from which to attempt to fetch substitutes for derivations, if the
29418 derivations aren't already available.
29420 @item @code{non-derivation-substitute-urls} (default: @code{#f})
29421 URLs from which to attempt to fetch substitutes for build inputs, if the
29422 input store items aren't already available.
29427 The Guix Build Coordinator package contains a script to query an
29428 instance of the Guix Data Service for derivations to build, and then
29429 submit builds for those derivations to the coordinator. The service
29430 type below assists in running this script. This is an additional tool
29431 that may be useful when building derivations contained within an
29432 instance of the Guix Data Service.
29434 @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
29435 Service type for the
29436 guix-build-coordinator-queue-builds-from-guix-data-service script. Its
29437 value must be a @code{guix-build-coordinator-queue-builds-configuration}
29441 @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
29442 Data type representing the options to the queue builds from guix data
29446 @item @code{package} (default: @code{guix-build-coordinator})
29447 The Guix Build Coordinator package to use.
29449 @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
29450 The system user to run the service as.
29452 @item @code{coordinator} (default: @code{"http://localhost:8745"})
29453 The URI to use when connecting to the coordinator.
29455 @item @code{systems} (default: @code{#f})
29456 The systems for which to fetch derivations to build.
29458 @item @code{systems-and-targets} (default: @code{#f})
29459 An association list of system and target pairs for which to fetch
29460 derivations to build.
29462 @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
29463 The Guix Data Service instance from which to query to find out about
29464 derivations to build.
29466 @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
29467 A file to record which commits have been processed, to avoid needlessly
29468 processing them again if the service is restarted.
29473 @subsubheading Guix Data Service
29474 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
29475 and provides data about GNU Guix. This includes information about
29476 packages, derivations and lint warnings.
29478 The data is stored in a PostgreSQL database, and available through a web
29481 @defvar {Scheme Variable} guix-data-service-type
29482 Service type for the Guix Data Service. Its value must be a
29483 @code{guix-data-service-configuration} object. The service optionally
29484 extends the getmail service, as the guix-commits mailing list is used to
29485 find out about changes in the Guix git repository.
29488 @deftp {Data Type} guix-data-service-configuration
29489 Data type representing the configuration of the Guix Data Service.
29492 @item @code{package} (default: @code{guix-data-service})
29493 The Guix Data Service package to use.
29495 @item @code{user} (default: @code{"guix-data-service"})
29496 The system user to run the service as.
29498 @item @code{group} (default: @code{"guix-data-service"})
29499 The system group to run the service as.
29501 @item @code{port} (default: @code{8765})
29502 The port to bind the web service to.
29504 @item @code{host} (default: @code{"127.0.0.1"})
29505 The host to bind the web service to.
29507 @item @code{getmail-idle-mailboxes} (default: @code{#f})
29508 If set, this is the list of mailboxes that the getmail service will be
29509 configured to listen to.
29511 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
29512 If set, this is the @code{getmail-retriever-configuration} object with
29513 which to configure getmail to fetch mail from the guix-commits mailing
29516 @item @code{extra-options} (default: @var{'()})
29517 Extra command line options for @code{guix-data-service}.
29519 @item @code{extra-process-jobs-options} (default: @var{'()})
29520 Extra command line options for @code{guix-data-service-process-jobs}.
29525 @node Linux Services
29526 @subsection Linux Services
29529 @cindex out of memory killer
29531 @cindex early out of memory daemon
29532 @subsubheading Early OOM Service
29534 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
29535 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
29536 space and provides a more responsive and configurable alternative to the
29537 in-kernel OOM killer. It is useful to prevent the system from becoming
29538 unresponsive when it runs out of memory.
29540 @deffn {Scheme Variable} earlyoom-service-type
29541 The service type for running @command{earlyoom}, the Early OOM daemon.
29542 Its value must be a @code{earlyoom-configuration} object, described
29543 below. The service can be instantiated in its default configuration
29547 (service earlyoom-service-type)
29551 @deftp {Data Type} earlyoom-configuration
29552 This is the configuration record for the @code{earlyoom-service-type}.
29555 @item @code{earlyoom} (default: @var{earlyoom})
29556 The Earlyoom package to use.
29558 @item @code{minimum-available-memory} (default: @code{10})
29559 The threshold for the minimum @emph{available} memory, in percentages.
29561 @item @code{minimum-free-swap} (default: @code{10})
29562 The threshold for the minimum free swap memory, in percentages.
29564 @item @code{prefer-regexp} (default: @code{#f})
29565 A regular expression (as a string) to match the names of the processes
29566 that should be preferably killed.
29568 @item @code{avoid-regexp} (default: @code{#f})
29569 A regular expression (as a string) to match the names of the processes
29570 that should @emph{not} be killed.
29572 @item @code{memory-report-interval} (default: @code{0})
29573 The interval in seconds at which a memory report is printed. It is
29574 disabled by default.
29576 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
29577 A boolean indicating whether the positive adjustments set in
29578 @file{/proc/*/oom_score_adj} should be ignored.
29580 @item @code{show-debug-messages?} (default: @code{#f})
29581 A boolean indicating whether debug messages should be printed. The logs
29582 are saved at @file{/var/log/earlyoom.log}.
29584 @item @code{send-notification-command} (default: @code{#f})
29585 This can be used to provide a custom command used for sending
29591 @cindex kernel module loader
29592 @subsubheading Kernel Module Loader Service
29594 The kernel module loader service allows one to load loadable kernel
29595 modules at boot. This is especially useful for modules that don't
29596 autoload and need to be manually loaded, as it's the case with
29599 @deffn {Scheme Variable} kernel-module-loader-service-type
29600 The service type for loading loadable kernel modules at boot with
29601 @command{modprobe}. Its value must be a list of strings representing
29602 module names. For example loading the drivers provided by
29603 @code{ddcci-driver-linux}, in debugging mode by passing some module
29604 parameters, can be done as follow:
29607 (use-modules (gnu) (gnu services))
29608 (use-package-modules linux)
29609 (use-service-modules linux)
29611 (define ddcci-config
29612 (plain-file "ddcci.conf"
29613 "options ddcci dyndbg delay=120"))
29617 (services (cons* (service kernel-module-loader-service-type
29618 '("ddcci" "ddcci_backlight"))
29619 (simple-service 'ddcci-config etc-service-type
29620 (list `("modprobe.d/ddcci.conf"
29623 (kernel-loadable-modules (list ddcci-driver-linux)))
29628 @cindex compressed swap
29629 @cindex Compressed RAM-based block devices
29630 @subsubheading Zram Device Service
29632 The Zram device service provides a compressed swap device in system
29633 memory. The Linux Kernel documentation has more information about
29634 @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
29637 @deffn {Scheme Variable} zram-device-service-type
29638 This service creates the zram block device, formats it as swap and
29639 enables it as a swap device. The service's value is a
29640 @code{zram-device-configuration} record.
29642 @deftp {Data Type} zram-device-configuration
29643 This is the data type representing the configuration for the zram-device
29647 @item @code{size} (default @code{"1G"})
29648 This is the amount of space you wish to provide for the zram device. It
29649 accepts a string and can be a number of bytes or use a suffix, eg.:
29650 @code{"512M"} or @code{1024000}.
29651 @item @code{compression-algorithm} (default @code{'lzo})
29652 This is the compression algorithm you wish to use. It is difficult to
29653 list all the possible compression options, but common ones supported by
29654 Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
29655 @item @code{memory-limit} (default @code{0})
29656 This is the maximum amount of memory which the zram device can use.
29657 Setting it to '0' disables the limit. While it is generally expected
29658 that compression will be 2:1, it is possible that uncompressable data
29659 can be written to swap and this is a method to limit how much memory can
29660 be used. It accepts a string and can be a number of bytes or use a
29661 suffix, eg.: @code{"2G"}.
29662 @item @code{priority} (default @code{-1})
29663 This is the priority of the swap device created from the zram device.
29664 @code{swapon} accepts values between -1 and 32767, with higher values
29665 indicating higher priority. Higher priority swap will generally be used
29672 @node Hurd Services
29673 @subsection Hurd Services
29675 @defvr {Scheme Variable} hurd-console-service-type
29676 This service starts the fancy @code{VGA} console client on the Hurd.
29678 The service's value is a @code{hurd-console-configuration} record.
29681 @deftp {Data Type} hurd-console-configuration
29682 This is the data type representing the configuration for the
29683 hurd-console-service.
29686 @item @code{hurd} (default: @var{hurd})
29687 The Hurd package to use.
29691 @defvr {Scheme Variable} hurd-getty-service-type
29692 This service starts a tty using the Hurd @code{getty} program.
29694 The service's value is a @code{hurd-getty-configuration} record.
29697 @deftp {Data Type} hurd-getty-configuration
29698 This is the data type representing the configuration for the
29699 hurd-getty-service.
29702 @item @code{hurd} (default: @var{hurd})
29703 The Hurd package to use.
29706 The name of the console this Getty runs on---e.g., @code{"tty1"}.
29708 @item @code{baud-rate} (default: @code{38400})
29709 An integer specifying the baud rate of the tty.
29714 @node Miscellaneous Services
29715 @subsection Miscellaneous Services
29717 @cindex fingerprint
29718 @subsubheading Fingerprint Service
29720 The @code{(gnu services authentication)} module provides a DBus service to
29721 read and identify fingerprints via a fingerprint sensor.
29723 @defvr {Scheme Variable} fprintd-service-type
29724 The service type for @command{fprintd}, which provides the fingerprint
29725 reading capability.
29728 (service fprintd-service-type)
29733 @subsubheading System Control Service
29735 The @code{(gnu services sysctl)} provides a service to configure kernel
29736 parameters at boot.
29738 @defvr {Scheme Variable} sysctl-service-type
29739 The service type for @command{sysctl}, which modifies kernel parameters
29740 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
29744 (service sysctl-service-type
29745 (sysctl-configuration
29746 (settings '(("net.ipv4.ip_forward" . "1")))))
29750 @deftp {Data Type} sysctl-configuration
29751 The data type representing the configuration of @command{sysctl}.
29754 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
29755 The @command{sysctl} executable to use.
29757 @item @code{settings} (default: @code{'()})
29758 An association list specifies kernel parameters and their values.
29763 @subsubheading PC/SC Smart Card Daemon Service
29765 The @code{(gnu services security-token)} module provides the following service
29766 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
29767 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
29768 manager that coordinates communications with smart card readers, smart cards
29769 and cryptographic tokens that are connected to the system.
29771 @defvr {Scheme Variable} pcscd-service-type
29772 Service type for the @command{pcscd} service. Its value must be a
29773 @code{pcscd-configuration} object. To run pcscd in the default
29774 configuration, instantiate it as:
29777 (service pcscd-service-type)
29781 @deftp {Data Type} pcscd-configuration
29782 The data type representing the configuration of @command{pcscd}.
29785 @item @code{pcsc-lite} (default: @code{pcsc-lite})
29786 The pcsc-lite package that provides pcscd.
29787 @item @code{usb-drivers} (default: @code{(list ccid)})
29788 List of packages that provide USB drivers to pcscd. Drivers are expected to be
29789 under @file{pcsc/drivers} in the store directory of the package.
29794 @subsubheading Lirc Service
29796 The @code{(gnu services lirc)} module provides the following service.
29798 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
29799 [#:device #f] [#:driver #f] [#:config-file #f] @
29800 [#:extra-options '()]
29801 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
29802 decodes infrared signals from remote controls.
29804 Optionally, @var{device}, @var{driver} and @var{config-file}
29805 (configuration file name) may be specified. See @command{lircd} manual
29808 Finally, @var{extra-options} is a list of additional command-line options
29809 passed to @command{lircd}.
29813 @subsubheading Spice Service
29815 The @code{(gnu services spice)} module provides the following service.
29817 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
29818 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
29819 that enables sharing the clipboard with a vm and setting the guest display
29820 resolution when the graphical console window resizes.
29823 @cindex inputattach
29824 @subsubheading inputattach Service
29826 @cindex tablet input, for Xorg
29827 @cindex touchscreen input, for Xorg
29828 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
29829 use input devices such as Wacom tablets, touchscreens, or joysticks with the
29830 Xorg display server.
29832 @deffn {Scheme Variable} inputattach-service-type
29833 Type of a service that runs @command{inputattach} on a device and
29834 dispatches events from it.
29837 @deftp {Data Type} inputattach-configuration
29839 @item @code{device-type} (default: @code{"wacom"})
29840 The type of device to connect to. Run @command{inputattach --help}, from the
29841 @code{inputattach} package, to see the list of supported device types.
29843 @item @code{device} (default: @code{"/dev/ttyS0"})
29844 The device file to connect to the device.
29846 @item @code{baud-rate} (default: @code{#f})
29847 Baud rate to use for the serial connection.
29848 Should be a number or @code{#f}.
29850 @item @code{log-file} (default: @code{#f})
29851 If true, this must be the name of a file to log messages to.
29855 @subsubheading Dictionary Service
29857 The @code{(gnu services dict)} module provides the following service:
29859 @defvr {Scheme Variable} dicod-service-type
29860 This is the type of the service that runs the @command{dicod} daemon, an
29861 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
29864 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
29865 Return a service that runs the @command{dicod} daemon, an implementation
29866 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
29868 The optional @var{config} argument specifies the configuration for
29869 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
29870 default it serves the GNU Collaborative International Dictionary of English.
29872 You can add @command{open localhost} to your @file{~/.dico} file to make
29873 @code{localhost} the default server for @command{dico} client
29874 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
29877 @deftp {Data Type} dicod-configuration
29878 Data type representing the configuration of dicod.
29881 @item @code{dico} (default: @var{dico})
29882 Package object of the GNU Dico dictionary server.
29884 @item @code{interfaces} (default: @var{'("localhost")})
29885 This is the list of IP addresses and ports and possibly socket file
29886 names to listen to (@pxref{Server Settings, @code{listen} directive,,
29887 dico, GNU Dico Manual}).
29889 @item @code{handlers} (default: @var{'()})
29890 List of @code{<dicod-handler>} objects denoting handlers (module instances).
29892 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
29893 List of @code{<dicod-database>} objects denoting dictionaries to be served.
29897 @deftp {Data Type} dicod-handler
29898 Data type representing a dictionary handler (module instance).
29902 Name of the handler (module instance).
29904 @item @code{module} (default: @var{#f})
29905 Name of the dicod module of the handler (instance). If it is @code{#f},
29906 the module has the same name as the handler.
29907 (@pxref{Modules,,, dico, GNU Dico Manual}).
29909 @item @code{options}
29910 List of strings or gexps representing the arguments for the module handler
29914 @deftp {Data Type} dicod-database
29915 Data type representing a dictionary database.
29919 Name of the database, will be used in DICT commands.
29921 @item @code{handler}
29922 Name of the dicod handler (module instance) used by this database
29923 (@pxref{Handlers,,, dico, GNU Dico Manual}).
29925 @item @code{complex?} (default: @var{#f})
29926 Whether the database configuration complex. The complex configuration
29927 will need a corresponding @code{<dicod-handler>} object, otherwise not.
29929 @item @code{options}
29930 List of strings or gexps representing the arguments for the database
29931 (@pxref{Databases,,, dico, GNU Dico Manual}).
29935 @defvr {Scheme Variable} %dicod-database:gcide
29936 A @code{<dicod-database>} object serving the GNU Collaborative International
29937 Dictionary of English using the @code{gcide} package.
29940 The following is an example @code{dicod-service} configuration.
29943 (dicod-service #:config
29944 (dicod-configuration
29945 (handlers (list (dicod-handler
29949 (list #~(string-append "dbdir=" #$wordnet))))))
29950 (databases (list (dicod-database
29953 (handler "wordnet")
29954 (options '("database=wn")))
29955 %dicod-database:gcide))))
29959 @subsubheading Docker Service
29961 The @code{(gnu services docker)} module provides the following services.
29963 @defvr {Scheme Variable} docker-service-type
29965 This is the type of the service that runs @url{https://www.docker.com,Docker},
29966 a daemon that can execute application bundles (sometimes referred to as
29967 ``containers'') in isolated environments.
29971 @deftp {Data Type} docker-configuration
29972 This is the data type representing the configuration of Docker and Containerd.
29976 @item @code{package} (default: @code{docker})
29977 The Docker daemon package to use.
29979 @item @code{package} (default: @code{docker-cli})
29980 The Docker client package to use.
29982 @item @code{containerd} (default: @var{containerd})
29983 The Containerd package to use.
29985 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
29986 The Docker user-land networking proxy package to use.
29988 @item @code{enable-proxy?} (default @code{#t})
29989 Enable or disable the use of the Docker user-land networking proxy.
29991 @item @code{debug?} (default @code{#f})
29992 Enable or disable debug output.
29994 @item @code{enable-iptables?} (default @code{#t})
29995 Enable or disable the addition of iptables rules.
30000 @cindex Singularity, container service
30001 @defvr {Scheme Variable} singularity-service-type
30002 This is the type of the service that allows you to run
30003 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
30004 create and run application bundles (aka. ``containers''). The value for this
30005 service is the Singularity package to use.
30007 The service does not install a daemon; instead, it installs helper programs as
30008 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
30009 @command{singularity run} and similar commands.
30013 @subsubheading Auditd Service
30015 The @code{(gnu services auditd)} module provides the following service.
30017 @defvr {Scheme Variable} auditd-service-type
30019 This is the type of the service that runs
30020 @url{https://people.redhat.com/sgrubb/audit/,auditd},
30021 a daemon that tracks security-relevant information on your system.
30023 Examples of things that can be tracked:
30033 Failed login attempts
30040 @command{auditctl} from the @code{audit} package can be used in order
30041 to add or remove events to be tracked (until the next reboot).
30042 In order to permanently track events, put the command line arguments
30043 of auditctl into a file called @code{audit.rules} in the configuration
30044 directory (see below).
30045 @command{aureport} from the @code{audit} package can be used in order
30046 to view a report of all recorded events.
30047 The audit daemon by default logs into the file
30048 @file{/var/log/audit.log}.
30052 @deftp {Data Type} auditd-configuration
30053 This is the data type representing the configuration of auditd.
30057 @item @code{audit} (default: @code{audit})
30058 The audit package to use.
30060 @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
30061 The directory containing the configuration file for the audit package, which
30062 must be named @code{auditd.conf}, and optionally some audit rules to
30063 instantiate on startup.
30069 @subsubheading R-Shiny service
30071 The @code{(gnu services science)} module provides the following service.
30073 @defvr {Scheme Variable} rshiny-service-type
30075 This is a type of service which is used to run a webapp created with
30076 @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
30077 variable and runs the provided script to call @code{runApp}.
30079 @deftp {Data Type} rshiny-configuration
30080 This is the data type representing the configuration of rshiny.
30084 @item @code{package} (default: @code{r-shiny})
30085 The package to use.
30087 @item @code{binary} (defaunlt @code{"rshiny"})
30088 The name of the binary or shell script located at @code{package/bin/} to
30089 run when the service is run.
30091 The common way to create this file is as follows:
30095 (let* ((out (assoc-ref %outputs "out"))
30096 (targetdir (string-append out "/share/" ,name))
30097 (app (string-append out "/bin/" ,name))
30098 (Rbin (string-append (assoc-ref %build-inputs "r-min")
30101 (mkdir-p (string-append out "/bin"))
30102 (call-with-output-file app
30108 runApp(launch.browser=0, port=4202)~%\n"
30117 @subsubheading Nix service
30119 The @code{(gnu services nix)} module provides the following service.
30121 @defvr {Scheme Variable} nix-service-type
30123 This is the type of the service that runs build daemon of the
30124 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
30128 (use-modules (gnu))
30129 (use-service-modules nix)
30130 (use-package-modules package-management)
30134 (packages (append (list nix)
30137 (services (append (list (service nix-service-type))
30141 After @command{guix system reconfigure} configure Nix for your user:
30144 @item Add a Nix channel and update it. See
30145 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
30147 @item Create a symlink to your profile and activate Nix profile:
30151 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
30152 $ source /run/current-system/profile/etc/profile.d/nix.sh
30157 @deftp {Data Type} nix-configuration
30158 This data type represents the configuration of the Nix daemon.
30161 @item @code{nix} (default: @code{nix})
30162 The Nix package to use.
30164 @item @code{sandbox} (default: @code{#t})
30165 Specifies whether builds are sandboxed by default.
30167 @item @code{build-sandbox-items} (default: @code{'()})
30168 This is a list of strings or objects appended to the
30169 @code{build-sandbox-items} field of the configuration file.
30171 @item @code{extra-config} (default: @code{'()})
30172 This is a list of strings or objects appended to the configuration file.
30173 It is used to pass extra text to be added verbatim to the configuration
30176 @item @code{extra-options} (default: @code{'()})
30177 Extra command line options for @code{nix-service-type}.
30181 @node Setuid Programs
30182 @section Setuid Programs
30184 @cindex setuid programs
30185 Some programs need to run with ``root'' privileges, even when they are
30186 launched by unprivileged users. A notorious example is the
30187 @command{passwd} program, which users can run to change their
30188 password, and which needs to access the @file{/etc/passwd} and
30189 @file{/etc/shadow} files---something normally restricted to root, for
30190 obvious security reasons. To address that, these executables are
30191 @dfn{setuid-root}, meaning that they always run with root privileges
30192 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
30193 for more info about the setuid mechanism).
30195 The store itself @emph{cannot} contain setuid programs: that would be a
30196 security issue since any user on the system can write derivations that
30197 populate the store (@pxref{The Store}). Thus, a different mechanism is
30198 used: instead of changing the setuid bit directly on files that are in
30199 the store, we let the system administrator @emph{declare} which programs
30200 should be setuid root.
30202 The @code{setuid-programs} field of an @code{operating-system}
30203 declaration contains a list of G-expressions denoting the names of
30204 programs to be setuid-root (@pxref{Using the Configuration System}).
30205 For instance, the @command{passwd} program, which is part of the Shadow
30206 package, can be designated by this G-expression (@pxref{G-Expressions}):
30209 #~(string-append #$shadow "/bin/passwd")
30212 A default set of setuid programs is defined by the
30213 @code{%setuid-programs} variable of the @code{(gnu system)} module.
30215 @defvr {Scheme Variable} %setuid-programs
30216 A list of G-expressions denoting common programs that are setuid-root.
30218 The list includes commands such as @command{passwd}, @command{ping},
30219 @command{su}, and @command{sudo}.
30222 Under the hood, the actual setuid programs are created in the
30223 @file{/run/setuid-programs} directory at system activation time. The
30224 files in this directory refer to the ``real'' binaries, which are in the
30227 @node X.509 Certificates
30228 @section X.509 Certificates
30230 @cindex HTTPS, certificates
30231 @cindex X.509 certificates
30233 Web servers available over HTTPS (that is, HTTP over the transport-layer
30234 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
30235 that the client can then use to @emph{authenticate} the server. To do
30236 that, clients verify that the server's certificate is signed by a
30237 so-called @dfn{certificate authority} (CA). But to verify the CA's
30238 signature, clients must have first acquired the CA's certificate.
30240 Web browsers such as GNU@tie{}IceCat include their own set of CA
30241 certificates, such that they are able to verify CA signatures
30244 However, most other programs that can talk HTTPS---@command{wget},
30245 @command{git}, @command{w3m}, etc.---need to be told where CA
30246 certificates can be found.
30248 @cindex @code{nss-certs}
30249 In Guix, this is done by adding a package that provides certificates
30250 to the @code{packages} field of the @code{operating-system} declaration
30251 (@pxref{operating-system Reference}). Guix includes one such package,
30252 @code{nss-certs}, which is a set of CA certificates provided as part of
30253 Mozilla's Network Security Services.
30255 Note that it is @emph{not} part of @code{%base-packages}, so you need to
30256 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
30257 most applications and libraries look for certificates by default, points
30258 to the certificates installed globally.
30260 Unprivileged users, including users of Guix on a foreign distro,
30261 can also install their own certificate package in
30262 their profile. A number of environment variables need to be defined so
30263 that applications and libraries know where to find them. Namely, the
30264 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
30265 variables. Some applications add their own environment variables; for
30266 instance, the Git version control system honors the certificate bundle
30267 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
30268 would typically run something like:
30271 guix install nss-certs
30272 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
30273 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
30274 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
30277 As another example, R requires the @env{CURL_CA_BUNDLE} environment
30278 variable to point to a certificate bundle, so you would have to run
30279 something like this:
30282 guix install nss-certs
30283 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
30286 For other applications you may want to look up the required environment
30287 variable in the relevant documentation.
30290 @node Name Service Switch
30291 @section Name Service Switch
30293 @cindex name service switch
30295 The @code{(gnu system nss)} module provides bindings to the
30296 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
30297 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
30298 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
30299 extended with new ``name'' lookup methods for system databases, which
30300 includes host names, service names, user accounts, and more (@pxref{Name
30301 Service Switch, System Databases and Name Service Switch,, libc, The GNU
30302 C Library Reference Manual}).
30304 The NSS configuration specifies, for each system database, which lookup
30305 method is to be used, and how the various methods are chained
30306 together---for instance, under which circumstances NSS should try the
30307 next method in the list. The NSS configuration is given in the
30308 @code{name-service-switch} field of @code{operating-system} declarations
30309 (@pxref{operating-system Reference, @code{name-service-switch}}).
30312 @cindex .local, host name lookup
30313 As an example, the declaration below configures the NSS to use the
30314 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
30315 back-end}, which supports host name lookups over multicast DNS (mDNS)
30316 for host names ending in @code{.local}:
30319 (name-service-switch
30320 (hosts (list %files ;first, check /etc/hosts
30322 ;; If the above did not succeed, try
30323 ;; with 'mdns_minimal'.
30325 (name "mdns_minimal")
30327 ;; 'mdns_minimal' is authoritative for
30328 ;; '.local'. When it returns "not found",
30329 ;; no need to try the next methods.
30330 (reaction (lookup-specification
30331 (not-found => return))))
30333 ;; Then fall back to DNS.
30337 ;; Finally, try with the "full" 'mdns'.
30342 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
30343 contains this configuration, so you will not have to type it if all you
30344 want is to have @code{.local} host lookup working.
30346 Note that, in this case, in addition to setting the
30347 @code{name-service-switch} of the @code{operating-system} declaration,
30348 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
30349 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
30350 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
30351 to the name service cache daemon (@pxref{Base Services,
30352 @code{nscd-service}}).
30354 For convenience, the following variables provide typical NSS
30357 @defvr {Scheme Variable} %default-nss
30358 This is the default name service switch configuration, a
30359 @code{name-service-switch} object.
30362 @defvr {Scheme Variable} %mdns-host-lookup-nss
30363 This is the name service switch configuration with support for host name
30364 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
30367 The reference for name service switch configuration is given below. It
30368 is a direct mapping of the configuration file format of the C library , so
30369 please refer to the C library manual for more information (@pxref{NSS
30370 Configuration File,,, libc, The GNU C Library Reference Manual}).
30371 Compared to the configuration file format of libc NSS, it has the advantage
30372 not only of adding this warm parenthetic feel that we like, but also
30373 static checks: you will know about syntax errors and typos as soon as you
30374 run @command{guix system}.
30376 @deftp {Data Type} name-service-switch
30378 This is the data type representation the configuration of libc's name
30379 service switch (NSS). Each field below represents one of the supported
30396 The system databases handled by the NSS. Each of these fields must be a
30397 list of @code{<name-service>} objects (see below).
30401 @deftp {Data Type} name-service
30403 This is the data type representing an actual name service and the
30404 associated lookup action.
30408 A string denoting the name service (@pxref{Services in the NSS
30409 configuration,,, libc, The GNU C Library Reference Manual}).
30411 Note that name services listed here must be visible to nscd. This is
30412 achieved by passing the @code{#:name-services} argument to
30413 @code{nscd-service} the list of packages providing the needed name
30414 services (@pxref{Base Services, @code{nscd-service}}).
30417 An action specified using the @code{lookup-specification} macro
30418 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
30419 Reference Manual}). For example:
30422 (lookup-specification (unavailable => continue)
30423 (success => return))
30428 @node Initial RAM Disk
30429 @section Initial RAM Disk
30432 @cindex initial RAM disk
30433 For bootstrapping purposes, the Linux-Libre kernel is passed an
30434 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
30435 root file system as well as an initialization script. The latter is
30436 responsible for mounting the real root file system, and for loading any
30437 kernel modules that may be needed to achieve that.
30439 The @code{initrd-modules} field of an @code{operating-system}
30440 declaration allows you to specify Linux-libre kernel modules that must
30441 be available in the initrd. In particular, this is where you would list
30442 modules needed to actually drive the hard disk where your root partition
30443 is---although the default value of @code{initrd-modules} should cover
30444 most use cases. For example, assuming you need the @code{megaraid_sas}
30445 module in addition to the default modules to be able to access your root
30446 file system, you would write:
30451 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
30454 @defvr {Scheme Variable} %base-initrd-modules
30455 This is the list of kernel modules included in the initrd by default.
30458 Furthermore, if you need lower-level customization, the @code{initrd}
30459 field of an @code{operating-system} declaration allows
30460 you to specify which initrd you would like to use. The @code{(gnu
30461 system linux-initrd)} module provides three ways to build an initrd: the
30462 high-level @code{base-initrd} procedure and the low-level
30463 @code{raw-initrd} and @code{expression->initrd} procedures.
30465 The @code{base-initrd} procedure is intended to cover most common uses.
30466 For example, if you want to add a bunch of kernel modules to be loaded
30467 at boot time, you can define the @code{initrd} field of the operating
30468 system declaration like this:
30471 (initrd (lambda (file-systems . rest)
30472 ;; Create a standard initrd but set up networking
30473 ;; with the parameters QEMU expects by default.
30474 (apply base-initrd file-systems
30475 #:qemu-networking? #t
30479 The @code{base-initrd} procedure also handles common use cases that
30480 involves using the system as a QEMU guest, or as a ``live'' system with
30481 volatile root file system.
30483 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
30484 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
30485 such as trying to guess which kernel modules and packages should be included
30486 to the initrd. An example use of @code{raw-initrd} is when a user has
30487 a custom Linux kernel configuration and default kernel modules included by
30488 @code{base-initrd} are not available.
30490 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
30491 honors several options passed on the Linux kernel command line
30492 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
30493 @code{-append} option of QEMU), notably:
30496 @item --load=@var{boot}
30497 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
30498 program, once it has mounted the root file system.
30500 Guix uses this option to yield control to a boot program that runs the
30501 service activation programs and then spawns the GNU@tie{}Shepherd, the
30502 initialization system.
30504 @item --root=@var{root}
30505 Mount @var{root} as the root file system. @var{root} can be a device
30506 name like @code{/dev/sda1}, a file system label, or a file system UUID.
30507 When unspecified, the device name from the root file system of the
30508 operating system declaration is used.
30510 @item --system=@var{system}
30511 Have @file{/run/booted-system} and @file{/run/current-system} point to
30514 @item modprobe.blacklist=@var{modules}@dots{}
30515 @cindex module, black-listing
30516 @cindex black list, of kernel modules
30517 Instruct the initial RAM disk as well as the @command{modprobe} command
30518 (from the kmod package) to refuse to load @var{modules}. @var{modules}
30519 must be a comma-separated list of module names---e.g.,
30520 @code{usbkbd,9pnet}.
30523 Start a read-eval-print loop (REPL) from the initial RAM disk before it
30524 tries to load kernel modules and to mount the root file system. Our
30525 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
30526 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
30527 Manual}, for more information on Guile's REPL.
30531 Now that you know all the features that initial RAM disks produced by
30532 @code{base-initrd} and @code{raw-initrd} provide,
30533 here is how to use it and customize it further.
30536 @cindex initial RAM disk
30537 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
30538 [#:linux-modules '()] [#:mapped-devices '()] @
30539 [#:keyboard-layout #f] @
30540 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
30541 Return a derivation that builds a raw initrd. @var{file-systems} is
30542 a list of file systems to be mounted by the initrd, possibly in addition to
30543 the root file system specified on the kernel command line via @option{--root}.
30544 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
30545 @var{mapped-devices} is a list of device mappings to realize before
30546 @var{file-systems} are mounted (@pxref{Mapped Devices}).
30547 @var{helper-packages} is a list of packages to be copied in the initrd. It may
30548 include @code{e2fsck/static} or other packages needed by the initrd to check
30549 the root file system.
30551 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
30552 the desired console keyboard layout. This is done before @var{mapped-devices}
30553 are set up and before @var{file-systems} are mounted such that, should the
30554 user need to enter a passphrase or use the REPL, this happens using the
30555 intended keyboard layout.
30557 When @var{qemu-networking?} is true, set up networking with the standard QEMU
30558 parameters. When @var{virtio?} is true, load additional modules so that the
30559 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
30561 When @var{volatile-root?} is true, the root file system is writable but any changes
30565 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
30566 [#:mapped-devices '()] [#:keyboard-layout #f] @
30567 [#:qemu-networking? #f] [#:volatile-root? #f] @
30568 [#:linux-modules '()]
30569 Return as a file-like object a generic initrd, with kernel
30570 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
30571 mounted by the initrd, possibly in addition to the root file system specified
30572 on the kernel command line via @option{--root}. @var{mapped-devices} is a list of device
30573 mappings to realize before @var{file-systems} are mounted.
30575 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
30576 the desired console keyboard layout. This is done before @var{mapped-devices}
30577 are set up and before @var{file-systems} are mounted such that, should the
30578 user need to enter a passphrase or use the REPL, this happens using the
30579 intended keyboard layout.
30581 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
30583 The initrd is automatically populated with all the kernel modules necessary
30584 for @var{file-systems} and for the given options. Additional kernel
30585 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
30586 loaded at boot time in the order in which they appear.
30589 Needless to say, the initrds we produce and use embed a
30590 statically-linked Guile, and the initialization program is a Guile
30591 program. That gives a lot of flexibility. The
30592 @code{expression->initrd} procedure builds such an initrd, given the
30593 program to run in that initrd.
30595 @deffn {Scheme Procedure} expression->initrd @var{exp} @
30596 [#:guile %guile-3.0-static-stripped] [#:name "guile-initrd"]
30597 Return as a file-like object a Linux initrd (a gzipped cpio archive)
30598 containing @var{guile} and that evaluates @var{exp}, a G-expression,
30599 upon booting. All the derivations referenced by @var{exp} are
30600 automatically copied to the initrd.
30603 @node Bootloader Configuration
30604 @section Bootloader Configuration
30607 @cindex boot loader
30609 The operating system supports multiple bootloaders. The bootloader is
30610 configured using @code{bootloader-configuration} declaration. All the
30611 fields of this structure are bootloader agnostic except for one field,
30612 @code{bootloader} that indicates the bootloader to be configured and
30615 Some of the bootloaders do not honor every field of
30616 @code{bootloader-configuration}. For instance, the extlinux
30617 bootloader does not support themes and thus ignores the @code{theme}
30620 @deftp {Data Type} bootloader-configuration
30621 The type of a bootloader configuration declaration.
30625 @item @code{bootloader}
30626 @cindex EFI, bootloader
30627 @cindex UEFI, bootloader
30628 @cindex BIOS, bootloader
30629 The bootloader to use, as a @code{bootloader} object. For now
30630 @code{grub-bootloader}, @code{grub-efi-bootloader},
30631 @code{grub-efi-netboot-bootloader}, @code{extlinux-bootloader} and
30632 @code{u-boot-bootloader} are supported.
30634 @cindex ARM, bootloaders
30635 @cindex AArch64, bootloaders
30636 Available bootloaders are described in @code{(gnu bootloader @dots{})}
30637 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
30638 of bootloaders for a wide range of ARM and AArch64 systems, using the
30639 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
30641 @vindex grub-efi-bootloader
30642 @code{grub-efi-bootloader} allows to boot on modern systems using the
30643 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
30644 use if the installation image contains a @file{/sys/firmware/efi} directory
30645 when you boot it on your system.
30647 @vindex grub-bootloader
30648 @code{grub-bootloader} allows you to boot in particular Intel-based machines
30649 in ``legacy'' BIOS mode.
30651 @vindex grub-efi-netboot-bootloader
30652 @code{grub-efi-netboot-bootloader} allows you to boot your system over network
30653 through TFTP. In combination with an NFS root file system this allows you to
30654 build a diskless Guix system.
30656 The installation of the @code{grub-efi-netboot-bootloader} generates the content
30657 of the TFTP root directory at @code{target}
30658 (@pxref{Bootloader Configuration, @code{target}}), to be served by a TFTP server.
30659 You may want to mount your TFTP server directory onto @code{target} to move the
30660 required files to the TFTP server automatically.
30662 If you plan to use an NFS root file system as well (actually if you mount the
30663 store from an NFS share), then the TFTP server needs to serve the file
30664 @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
30665 image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
30666 initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
30667 files from the store will be accessed by GRUB through TFTP with their normal
30668 store path, for example as
30669 @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
30671 Two symlinks are created to make this possible. The first symlink is
30672 @code{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
30673 @file{../../../boot/grub/grub.cfg},
30674 where @code{target} may be @file{/boot}. In this case the link is not leaving
30675 the served TFTP root directory, but otherwise it does. The second link is
30676 @code{target}@file{/gnu/store} and points to @file{../gnu/store}. This link
30677 is leaving the served TFTP root directory.
30679 The assumption behind all this is that you have an NFS server exporting the root
30680 file system for your Guix system, and additionally a TFTP server exporting your
30681 @code{target} directory—usually @file{/boot}—from that same root file system for
30682 your Guix system. In this constellation the symlinks will work.
30684 For other constellations you will have to program your own bootloader installer,
30685 which then takes care to make necessary files from the store accessible through
30686 TFTP, for example by copying them into the TFTP root directory at @code{target}.
30688 It is important to note that symlinks pointing outside the TFTP root directory
30689 may need to be allowed in the configuration of your TFTP server. Further the
30690 store link exposes the whole store through TFTP. Both points need to be
30691 considered carefully for security aspects.
30693 Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
30694 NFS servers, you also need a properly configured DHCP server to make the booting
30695 over netboot possible. For all this we can currently only recommend you to look
30696 for instructions about @acronym{PXE, Preboot eXecution Environment}.
30698 @item @code{target}
30699 This is a string denoting the target onto which to install the
30702 The interpretation depends on the bootloader in question. For
30703 @code{grub-bootloader}, for example, it should be a device name understood by
30704 the bootloader @command{installer} command, such as @code{/dev/sda} or
30705 @code{(hd0)} (@pxref{Invoking grub-install,,, grub, GNU GRUB Manual}). For
30706 @code{grub-efi-bootloader}, it should be the mount point of the EFI file
30707 system, usually @file{/boot/efi}. For @code{grub-efi-netboot-bootloader},
30708 @code{target} should be the mount point corresponding to the TFTP root
30709 directory of your TFTP server.
30711 @item @code{menu-entries} (default: @code{()})
30712 A possibly empty list of @code{menu-entry} objects (see below), denoting
30713 entries to appear in the bootloader menu, in addition to the current
30714 system entry and the entry pointing to previous system generations.
30716 @item @code{default-entry} (default: @code{0})
30717 The index of the default boot menu entry. Index 0 is for the entry of the
30720 @item @code{timeout} (default: @code{5})
30721 The number of seconds to wait for keyboard input before booting. Set to
30722 0 to boot immediately, and to -1 to wait indefinitely.
30724 @cindex keyboard layout, for the bootloader
30725 @item @code{keyboard-layout} (default: @code{#f})
30726 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
30727 layout, usually US@tie{}English (``qwerty'').
30729 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
30733 This option is currently ignored by bootloaders other than @code{grub} and
30737 @item @code{theme} (default: @var{#f})
30738 The bootloader theme object describing the theme to use. If no theme
30739 is provided, some bootloaders might use a default theme, that's true
30742 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
30743 The output terminals used for the bootloader boot menu, as a list of
30744 symbols. GRUB accepts the values: @code{console}, @code{serial},
30745 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
30746 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
30747 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
30748 configuration,,, grub,GNU GRUB manual}).
30750 @item @code{terminal-inputs} (default: @code{'()})
30751 The input terminals used for the bootloader boot menu, as a list of
30752 symbols. For GRUB, the default is the native platform terminal as
30753 determined at run-time. GRUB accepts the values: @code{console},
30754 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
30755 @code{usb_keyboard}. This field corresponds to the GRUB variable
30756 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
30759 @item @code{serial-unit} (default: @code{#f})
30760 The serial unit used by the bootloader, as an integer from 0 to 3.
30761 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
30762 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
30764 @item @code{serial-speed} (default: @code{#f})
30765 The speed of the serial interface, as an integer. For GRUB, the
30766 default value is chosen at run-time; currently GRUB chooses
30767 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
30774 Should you want to list additional boot menu entries @i{via} the
30775 @code{menu-entries} field above, you will need to create them with the
30776 @code{menu-entry} form. For example, imagine you want to be able to
30777 boot another distro (hard to imagine!), you can define a menu entry
30782 (label "The Other Distro")
30783 (linux "/boot/old/vmlinux-2.6.32")
30784 (linux-arguments '("root=/dev/sda2"))
30785 (initrd "/boot/old/initrd"))
30790 @deftp {Data Type} menu-entry
30791 The type of an entry in the bootloader menu.
30796 The label to show in the menu---e.g., @code{"GNU"}.
30798 @item @code{linux} (default: @code{#f})
30799 The Linux kernel image to boot, for example:
30802 (file-append linux-libre "/bzImage")
30805 For GRUB, it is also possible to specify a device explicitly in the
30806 file path using GRUB's device naming convention (@pxref{Naming
30807 convention,,, grub, GNU GRUB manual}), for example:
30810 "(hd0,msdos1)/boot/vmlinuz"
30813 If the device is specified explicitly as above, then the @code{device}
30814 field is ignored entirely.
30816 @item @code{linux-arguments} (default: @code{()})
30817 The list of extra Linux kernel command-line arguments---e.g.,
30818 @code{("console=ttyS0")}.
30820 @item @code{initrd} (default: @code{#f})
30821 A G-Expression or string denoting the file name of the initial RAM disk
30822 to use (@pxref{G-Expressions}).
30824 @item @code{device} (default: @code{#f})
30825 The device where the kernel and initrd are to be found---i.e., for GRUB,
30826 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
30828 This may be a file system label (a string), a file system UUID (a
30829 bytevector, @pxref{File Systems}), or @code{#f}, in which case
30830 the bootloader will search the device containing the file specified by
30831 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
30832 must @emph{not} be an OS device name such as @file{/dev/sda1}.
30834 @item @code{multiboot-kernel} (default: @code{#f})
30835 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
30836 manual}). When this field is set, a Multiboot menu-entry is generated.
30840 (file-append mach "/boot/gnumach")
30843 @item @code{multiboot-arguments} (default: @code{()})
30844 The list of extra command-line arguments for the multiboot-kernel.
30846 @item @code{multiboot-modules} (default: @code{()})
30847 The list of commands for loading Multiboot modules. For example:
30850 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
30852 (list (file-append libc "/lib/ld.so.1") "exec"
30862 @c FIXME: Write documentation once it's stable.
30863 For now only GRUB has theme support. GRUB themes are created using
30864 the @code{grub-theme} form, which is not fully documented yet.
30866 @deftp {Data Type} grub-theme
30867 Data type representing the configuration of the GRUB theme.
30870 @item @code{gfxmode} (default: @code{'("auto")})
30871 The GRUB @code{gfxmode} to set (a list of screen resolution strings,
30872 @pxref{gfxmode,,, grub, GNU GRUB manual}).
30876 @deffn {Scheme Procedure} grub-theme
30877 Return the default GRUB theme used by the operating system if no
30878 @code{theme} field is specified in @code{bootloader-configuration}
30881 It comes with a fancy background image displaying the GNU and Guix
30885 For example, to override the default resolution, you may use something
30890 (bootloader-configuration
30893 (inherit (grub-theme))
30894 (gfxmode '("1024x786x32" "auto"))))))
30897 @node Invoking guix system
30898 @section Invoking @code{guix system}
30900 Once you have written an operating system declaration as seen in the
30901 previous section, it can be @dfn{instantiated} using the @command{guix
30902 system} command. The synopsis is:
30905 guix system @var{options}@dots{} @var{action} @var{file}
30908 @var{file} must be the name of a file containing an
30909 @code{operating-system} declaration. @var{action} specifies how the
30910 operating system is instantiated. Currently the following values are
30915 Display available service type definitions that match the given regular
30916 expressions, sorted by relevance:
30922 $ guix system search console
30923 name: console-fonts
30924 location: gnu/services/base.scm:806:2
30925 extends: shepherd-root
30926 description: Install the given fonts on the specified ttys (fonts are per
30927 + virtual console on GNU/Linux). The value of this service is a list of
30928 + tty/font pairs. The font can be the name of a font provided by the `kbd'
30929 + package or any valid argument to `setfont', as in this example:
30931 + '(("tty1" . "LatGrkCyr-8x16")
30932 + ("tty2" . (file-append
30934 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
30935 + ("tty3" . (file-append
30937 + "/share/consolefonts/ter-132n"))) ; for HDPI
30941 location: gnu/services/base.scm:1190:2
30942 extends: shepherd-root
30943 description: Provide console login using the `mingetty' program.
30947 location: gnu/services/base.scm:860:2
30949 description: Provide a console log-in service as specified by its
30950 + configuration value, a `login-configuration' object.
30956 As for @command{guix package --search}, the result is written in
30957 @code{recutils} format, which makes it easy to filter the output
30958 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
30961 Build the operating system described in @var{file}, activate it, and
30962 switch to it@footnote{This action (and the related actions
30963 @code{switch-generation} and @code{roll-back}) are usable only on
30964 systems already running Guix System.}.
30967 @c The paragraph below refers to the problem discussed at
30968 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
30969 It is highly recommended to run @command{guix pull} once before you run
30970 @command{guix system reconfigure} for the first time (@pxref{Invoking
30971 guix pull}). Failing to do that you would see an older version of Guix
30972 once @command{reconfigure} has completed.
30975 This effects all the configuration specified in @var{file}: user
30976 accounts, system services, global package list, setuid programs, etc.
30977 The command starts system services specified in @var{file} that are not
30978 currently running; if a service is currently running this command will
30979 arrange for it to be upgraded the next time it is stopped (e.g.@: by
30980 @code{herd stop X} or @code{herd restart X}).
30982 This command creates a new generation whose number is one greater than
30983 the current generation (as reported by @command{guix system
30984 list-generations}). If that generation already exists, it will be
30985 overwritten. This behavior mirrors that of @command{guix package}
30986 (@pxref{Invoking guix package}).
30988 It also adds a bootloader menu entry for the new OS configuration,
30989 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
30990 entries for older configurations to a submenu, allowing you to choose
30991 an older system generation at boot time should you need it.
30993 @cindex provenance tracking, of the operating system
30994 Upon completion, the new system is deployed under
30995 @file{/run/current-system}. This directory contains @dfn{provenance
30996 meta-data}: the list of channels in use (@pxref{Channels}) and
30997 @var{file} itself, when available. You can view it by running:
31000 guix system describe
31003 This information is useful should you later want to inspect how this
31004 particular generation was built. In fact, assuming @var{file} is
31005 self-contained, you can later rebuild generation @var{n} of your
31006 operating system with:
31009 guix time-machine \
31010 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
31011 system reconfigure \
31012 /var/guix/profiles/system-@var{n}-link/configuration.scm
31015 You can think of it as some sort of built-in version control! Your
31016 system is not just a binary artifact: @emph{it carries its own source}.
31017 @xref{Service Reference, @code{provenance-service-type}}, for more
31018 information on provenance tracking.
31020 By default, @command{reconfigure} @emph{prevents you from downgrading
31021 your system}, which could (re)introduce security vulnerabilities and
31022 also cause problems with ``stateful'' services such as database
31023 management systems. You can override that behavior by passing
31024 @option{--allow-downgrades}.
31026 @item switch-generation
31027 @cindex generations
31028 Switch to an existing system generation. This action atomically
31029 switches the system profile to the specified system generation. It
31030 also rearranges the system's existing bootloader menu entries. It
31031 makes the menu entry for the specified system generation the default,
31032 and it moves the entries for the other generations to a submenu, if
31033 supported by the bootloader being used. The next time the system
31034 boots, it will use the specified system generation.
31036 The bootloader itself is not being reinstalled when using this
31037 command. Thus, the installed bootloader is used with an updated
31038 configuration file.
31040 The target generation can be specified explicitly by its generation
31041 number. For example, the following invocation would switch to system
31045 guix system switch-generation 7
31048 The target generation can also be specified relative to the current
31049 generation with the form @code{+N} or @code{-N}, where @code{+3} means
31050 ``3 generations ahead of the current generation,'' and @code{-1} means
31051 ``1 generation prior to the current generation.'' When specifying a
31052 negative value such as @code{-1}, you must precede it with @code{--} to
31053 prevent it from being parsed as an option. For example:
31056 guix system switch-generation -- -1
31059 Currently, the effect of invoking this action is @emph{only} to switch
31060 the system profile to an existing generation and rearrange the
31061 bootloader menu entries. To actually start using the target system
31062 generation, you must reboot after running this action. In the future,
31063 it will be updated to do the same things as @command{reconfigure},
31064 like activating and deactivating services.
31066 This action will fail if the specified generation does not exist.
31069 @cindex rolling back
31070 Switch to the preceding system generation. The next time the system
31071 boots, it will use the preceding system generation. This is the inverse
31072 of @command{reconfigure}, and it is exactly the same as invoking
31073 @command{switch-generation} with an argument of @code{-1}.
31075 Currently, as with @command{switch-generation}, you must reboot after
31076 running this action to actually start using the preceding system
31079 @item delete-generations
31080 @cindex deleting system generations
31081 @cindex saving space
31082 Delete system generations, making them candidates for garbage collection
31083 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
31086 This works in the same way as @samp{guix package --delete-generations}
31087 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
31088 arguments, all system generations but the current one are deleted:
31091 guix system delete-generations
31094 You can also select the generations you want to delete. The example below
31095 deletes all the system generations that are more than two month old:
31098 guix system delete-generations 2m
31101 Running this command automatically reinstalls the bootloader with an updated
31102 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
31103 longer lists the generations that have been deleted.
31106 Build the derivation of the operating system, which includes all the
31107 configuration files and programs needed to boot and run the system.
31108 This action does not actually install anything.
31111 Populate the given directory with all the files necessary to run the
31112 operating system specified in @var{file}. This is useful for first-time
31113 installations of Guix System. For instance:
31116 guix system init my-os-config.scm /mnt
31119 copies to @file{/mnt} all the store items required by the configuration
31120 specified in @file{my-os-config.scm}. This includes configuration
31121 files, packages, and so on. It also creates other essential files
31122 needed for the system to operate correctly---e.g., the @file{/etc},
31123 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
31125 This command also installs bootloader on the target specified in
31126 @file{my-os-config}, unless the @option{--no-bootloader} option was
31130 @cindex virtual machine
31132 @anchor{guix system vm}
31133 Build a virtual machine that contains the operating system declared in
31134 @var{file}, and return a script to run that virtual machine (VM).
31137 The @code{vm} action and others below
31138 can use KVM support in the Linux-libre kernel. Specifically, if the
31139 machine has hardware virtualization support, the corresponding
31140 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
31141 must exist and be readable and writable by the user and by the
31142 build users of the daemon (@pxref{Build Environment Setup}).
31145 Arguments given to the script are passed to QEMU as in the example
31146 below, which enables networking and requests 1@tie{}GiB of RAM for the
31150 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -net user,model=virtio-net-pci
31153 The VM shares its store with the host system.
31155 Additional file systems can be shared between the host and the VM using
31156 the @option{--share} and @option{--expose} command-line options: the former
31157 specifies a directory to be shared with write access, while the latter
31158 provides read-only access to the shared directory.
31160 The example below creates a VM in which the user's home directory is
31161 accessible read-only, and where the @file{/exchange} directory is a
31162 read-write mapping of @file{$HOME/tmp} on the host:
31165 guix system vm my-config.scm \
31166 --expose=$HOME --share=$HOME/tmp=/exchange
31169 On GNU/Linux, the default is to boot directly to the kernel; this has
31170 the advantage of requiring only a very tiny root disk image since the
31171 store of the host can then be mounted.
31173 The @option{--full-boot} option forces a complete boot sequence, starting
31174 with the bootloader. This requires more disk space since a root image
31175 containing at least the kernel, initrd, and bootloader data files must
31176 be created. The @option{--image-size} option can be used to specify the
31179 @cindex System images, creation in various formats
31180 @cindex Creating system images in various formats
31183 @itemx docker-image
31184 Return a virtual machine, disk image, or Docker image of the operating
31185 system declared in @var{file} that stands alone. By default,
31186 @command{guix system} estimates the size of the image needed to store
31187 the system, but you can use the @option{--image-size} option to specify
31188 a value. Docker images are built to contain exactly what they need, so
31189 the @option{--image-size} option is ignored in the case of
31190 @code{docker-image}.
31192 @cindex disk-image, creating disk images
31193 The @code{disk-image} command can produce various image types. The
31194 image type can be selected using the @option{--image-type} option. It
31195 defaults to @code{raw}. When its value is @code{iso9660}, the
31196 @option{--label} option can be used to specify a volume ID with
31197 @code{disk-image}. By default, the root file system of a disk image is
31198 mounted non-volatile; the @option{--volatile} option can be provided to
31199 make it volatile instead. When using @code{disk-image}, the bootloader
31200 installed on the generated image is taken from the provided
31201 @code{operating-system} definition. The following example demonstrates
31202 how to generate an image that uses the @code{grub-efi-bootloader}
31203 bootloader and boot it with QEMU:
31206 image=$(guix system disk-image --image-type=qcow2 \
31207 gnu/system/examples/lightweight-desktop.tmpl)
31208 cp $image /tmp/my-image.qcow2
31209 chmod +w /tmp/my-image.qcow2
31210 qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
31211 -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
31214 When using the @code{raw} image type, a raw disk image is produced; it
31215 can be copied as is to a USB stick, for instance. Assuming
31216 @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
31217 the image to it using the following command:
31220 # dd if=$(guix system disk-image my-os.scm) of=/dev/sdc status=progress
31223 The @code{--list-image-types} command lists all the available image
31226 @cindex vm-image, creating virtual machine images
31227 When using @code{vm-image}, the returned image is in qcow2 format, which
31228 the QEMU emulator can efficiently use. @xref{Running Guix in a VM}, for
31229 more information on how to run the image in a virtual machine. The
31230 @code{grub-bootloader} bootloader is always used independently of what
31231 is declared in the @code{operating-system} file passed as argument.
31232 This is to make it easier to work with QEMU, which uses the SeaBIOS BIOS
31233 by default, expecting a bootloader to be installed in the Master Boot
31236 @cindex docker-image, creating docker images
31237 When using @code{docker-image}, a Docker image is produced. Guix builds
31238 the image from scratch, not from a pre-existing Docker base image. As a
31239 result, it contains @emph{exactly} what you define in the operating
31240 system configuration file. You can then load the image and launch a
31241 Docker container using commands like the following:
31244 image_id="`docker load < guix-system-docker-image.tar.gz`"
31245 container_id="`docker create $image_id`"
31246 docker start $container_id
31249 This command starts a new Docker container from the specified image. It
31250 will boot the Guix system in the usual manner, which means it will
31251 start any services you have defined in the operating system
31252 configuration. You can get an interactive shell running in the container
31253 using @command{docker exec}:
31256 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
31259 Depending on what you run in the Docker container, it
31260 may be necessary to give the container additional permissions. For
31261 example, if you intend to build software using Guix inside of the Docker
31262 container, you may need to pass the @option{--privileged} option to
31263 @code{docker create}.
31265 Last, the @option{--network} option applies to @command{guix system
31266 docker-image}: it produces an image where network is supposedly shared
31267 with the host, and thus without services like nscd or NetworkManager.
31270 Return a script to run the operating system declared in @var{file}
31271 within a container. Containers are a set of lightweight isolation
31272 mechanisms provided by the kernel Linux-libre. Containers are
31273 substantially less resource-demanding than full virtual machines since
31274 the kernel, shared objects, and other resources can be shared with the
31275 host system; this also means they provide thinner isolation.
31277 Currently, the script must be run as root in order to support more than
31278 a single user and group. The container shares its store with the host
31281 As with the @code{vm} action (@pxref{guix system vm}), additional file
31282 systems to be shared between the host and container can be specified
31283 using the @option{--share} and @option{--expose} options:
31286 guix system container my-config.scm \
31287 --expose=$HOME --share=$HOME/tmp=/exchange
31291 This option requires Linux-libre 3.19 or newer.
31296 @var{options} can contain any of the common build options (@pxref{Common
31297 Build Options}). In addition, @var{options} can contain one of the
31301 @item --expression=@var{expr}
31302 @itemx -e @var{expr}
31303 Consider the operating-system @var{expr} evaluates to.
31304 This is an alternative to specifying a file which evaluates to an
31306 This is used to generate the Guix system installer @pxref{Building the
31307 Installation Image}).
31309 @item --system=@var{system}
31310 @itemx -s @var{system}
31311 Attempt to build for @var{system} instead of the host system type.
31312 This works as per @command{guix build} (@pxref{Invoking guix build}).
31316 Return the derivation file name of the given operating system without
31319 @cindex provenance tracking, of the operating system
31320 @item --save-provenance
31321 As discussed above, @command{guix system init} and @command{guix system
31322 reconfigure} always save provenance information @i{via} a dedicated
31323 service (@pxref{Service Reference, @code{provenance-service-type}}).
31324 However, other commands don't do that by default. If you wish to, say,
31325 create a virtual machine image that contains provenance information, you
31329 guix system vm-image --save-provenance config.scm
31332 That way, the resulting image will effectively ``embed its own source''
31333 in the form of meta-data in @file{/run/current-system}. With that
31334 information, one can rebuild the image to make sure it really contains
31335 what it pretends to contain; or they could use that to derive a variant
31338 @item --image-type=@var{type}
31339 @itemx -t @var{type}
31340 For the @code{disk-image} action, create an image with given @var{type}.
31342 When this option is omitted, @command{guix system} uses the @code{raw}
31345 @cindex ISO-9660 format
31346 @cindex CD image format
31347 @cindex DVD image format
31348 @option{--image-type=iso9660} produces an ISO-9660 image, suitable
31349 for burning on CDs and DVDs.
31351 @item --image-size=@var{size}
31352 For the @code{vm-image} and @code{disk-image} actions, create an image
31353 of the given @var{size}. @var{size} may be a number of bytes, or it may
31354 include a unit as a suffix (@pxref{Block size, size specifications,,
31355 coreutils, GNU Coreutils}).
31357 When this option is omitted, @command{guix system} computes an estimate
31358 of the image size as a function of the size of the system declared in
31363 For the @code{container} action, allow containers to access the host network,
31364 that is, do not create a network namespace.
31366 @item --root=@var{file}
31367 @itemx -r @var{file}
31368 Make @var{file} a symlink to the result, and register it as a garbage
31371 @item --skip-checks
31372 Skip pre-installation safety checks.
31374 By default, @command{guix system init} and @command{guix system
31375 reconfigure} perform safety checks: they make sure the file systems that
31376 appear in the @code{operating-system} declaration actually exist
31377 (@pxref{File Systems}), and that any Linux kernel modules that may be
31378 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
31379 RAM Disk}). Passing this option skips these tests altogether.
31381 @item --allow-downgrades
31382 Instruct @command{guix system reconfigure} to allow system downgrades.
31384 By default, @command{reconfigure} prevents you from downgrading your
31385 system. It achieves that by comparing the provenance info of your
31386 system (shown by @command{guix system describe}) with that of your
31387 @command{guix} command (shown by @command{guix describe}). If the
31388 commits for @command{guix} are not descendants of those used for your
31389 system, @command{guix system reconfigure} errors out. Passing
31390 @option{--allow-downgrades} allows you to bypass these checks.
31393 Make sure you understand its security implications before using
31394 @option{--allow-downgrades}.
31398 @cindex on-error strategy
31399 @cindex error strategy
31400 @item --on-error=@var{strategy}
31401 Apply @var{strategy} when an error occurs when reading @var{file}.
31402 @var{strategy} may be one of the following:
31405 @item nothing-special
31406 Report the error concisely and exit. This is the default strategy.
31409 Likewise, but also display a backtrace.
31412 Report the error and enter Guile's debugger. From there, you can run
31413 commands such as @code{,bt} to get a backtrace, @code{,locals} to
31414 display local variable values, and more generally inspect the state of the
31415 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
31416 a list of available debugging commands.
31420 Once you have built, configured, re-configured, and re-re-configured
31421 your Guix installation, you may find it useful to list the operating
31422 system generations available on disk---and that you can choose from the
31423 bootloader boot menu:
31428 Describe the current system generation: its file name, the kernel and
31429 bootloader used, etc., as well as provenance information when available.
31431 @item list-generations
31432 List a summary of each generation of the operating system available on
31433 disk, in a human-readable way. This is similar to the
31434 @option{--list-generations} option of @command{guix package}
31435 (@pxref{Invoking guix package}).
31437 Optionally, one can specify a pattern, with the same syntax that is used
31438 in @command{guix package --list-generations}, to restrict the list of
31439 generations displayed. For instance, the following command displays
31440 generations that are up to 10 days old:
31443 $ guix system list-generations 10d
31448 The @command{guix system} command has even more to offer! The following
31449 sub-commands allow you to visualize how your system services relate to
31452 @anchor{system-extension-graph}
31455 @item extension-graph
31456 Emit in Dot/Graphviz format to standard output the @dfn{service
31457 extension graph} of the operating system defined in @var{file}
31458 (@pxref{Service Composition}, for more information on service
31464 $ guix system extension-graph @var{file} | xdot -
31467 shows the extension relations among services.
31469 @anchor{system-shepherd-graph}
31470 @item shepherd-graph
31471 Emit in Dot/Graphviz format to standard output the @dfn{dependency
31472 graph} of shepherd services of the operating system defined in
31473 @var{file}. @xref{Shepherd Services}, for more information and for an
31478 @node Invoking guix deploy
31479 @section Invoking @code{guix deploy}
31481 We've already seen @code{operating-system} declarations used to manage a
31482 machine's configuration locally. Suppose you need to configure multiple
31483 machines, though---perhaps you're managing a service on the web that's
31484 comprised of several servers. @command{guix deploy} enables you to use those
31485 same @code{operating-system} declarations to manage multiple remote hosts at
31486 once as a logical ``deployment''.
31489 The functionality described in this section is still under development
31490 and is subject to change. Get in touch with us on
31491 @email{guix-devel@@gnu.org}!
31495 guix deploy @var{file}
31498 Such an invocation will deploy the machines that the code within @var{file}
31499 evaluates to. As an example, @var{file} might contain a definition like this:
31502 ;; This is a Guix deployment of a "bare bones" setup, with
31503 ;; no X11 display server, to a machine with an SSH daemon
31504 ;; listening on localhost:2222. A configuration such as this
31505 ;; may be appropriate for virtual machine with ports
31506 ;; forwarded to the host's loopback interface.
31508 (use-service-modules networking ssh)
31509 (use-package-modules bootloaders)
31513 (host-name "gnu-deployed")
31514 (timezone "Etc/UTC")
31515 (bootloader (bootloader-configuration
31516 (bootloader grub-bootloader)
31517 (target "/dev/vda")
31518 (terminal-outputs '(console))))
31519 (file-systems (cons (file-system
31521 (device "/dev/vda1")
31523 %base-file-systems))
31525 (append (list (service dhcp-client-service-type)
31526 (service openssh-service-type
31527 (openssh-configuration
31528 (permit-root-login #t)
31529 (allow-empty-passwords? #t))))
31533 (operating-system %system)
31534 (environment managed-host-environment-type)
31535 (configuration (machine-ssh-configuration
31536 (host-name "localhost")
31537 (system "x86_64-linux")
31539 (identity "./id_rsa")
31543 The file should evaluate to a list of @var{machine} objects. This example,
31544 upon being deployed, will create a new generation on the remote system
31545 realizing the @code{operating-system} declaration @code{%system}.
31546 @code{environment} and @code{configuration} specify how the machine should be
31547 provisioned---that is, how the computing resources should be created and
31548 managed. The above example does not create any resources, as a
31549 @code{'managed-host} is a machine that is already running the Guix system and
31550 available over the network. This is a particularly simple case; a more
31551 complex deployment may involve, for example, starting virtual machines through
31552 a Virtual Private Server (VPS) provider. In such a case, a different
31553 @var{environment} type would be used.
31555 Do note that you first need to generate a key pair on the coordinator machine
31556 to allow the daemon to export signed archives of files from the store
31557 (@pxref{Invoking guix archive}), though this step is automatic on Guix
31561 # guix archive --generate-key
31565 Each target machine must authorize the key of the master machine so that it
31566 accepts store items it receives from the coordinator:
31569 # guix archive --authorize < coordinator-public-key.txt
31572 @code{user}, in this example, specifies the name of the user account to log in
31573 as to perform the deployment. Its default value is @code{root}, but root
31574 login over SSH may be forbidden in some cases. To work around this,
31575 @command{guix deploy} can log in as an unprivileged user and employ
31576 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
31577 currently installed on the remote and can be invoked non-interactively as
31578 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
31579 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
31580 be accomplished with the following operating system configuration snippet:
31584 (gnu system)) ;for %sudoers-specification
31586 (define %user "username")
31591 (plain-file "sudoers"
31592 (string-append (plain-file-content %sudoers-specification)
31593 (format #f "~a ALL = NOPASSWD: ALL~%"
31598 For more information regarding the format of the @file{sudoers} file,
31599 consult @command{man sudoers}.
31601 @deftp {Data Type} machine
31602 This is the data type representing a single machine in a heterogeneous Guix
31606 @item @code{operating-system}
31607 The object of the operating system configuration to deploy.
31609 @item @code{environment}
31610 An @code{environment-type} describing how the machine should be provisioned.
31612 @item @code{configuration} (default: @code{#f})
31613 An object describing the configuration for the machine's @code{environment}.
31614 If the @code{environment} has a default configuration, @code{#f} may be used.
31615 If @code{#f} is used for an environment with no default configuration,
31616 however, an error will be thrown.
31620 @deftp {Data Type} machine-ssh-configuration
31621 This is the data type representing the SSH client parameters for a machine
31622 with an @code{environment} of @code{managed-host-environment-type}.
31625 @item @code{host-name}
31626 @item @code{build-locally?} (default: @code{#t})
31627 If false, system derivations will be built on the machine being deployed to.
31628 @item @code{system}
31629 The system type describing the architecture of the machine being deployed
31630 to---e.g., @code{"x86_64-linux"}.
31631 @item @code{authorize?} (default: @code{#t})
31632 If true, the coordinator's signing key will be added to the remote's ACL
31634 @item @code{port} (default: @code{22})
31635 @item @code{user} (default: @code{"root"})
31636 @item @code{identity} (default: @code{#f})
31637 If specified, the path to the SSH private key to use to authenticate with the
31640 @item @code{host-key} (default: @code{#f})
31641 This should be the SSH host key of the machine, which looks like this:
31644 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
31647 When @code{host-key} is @code{#f}, the server is authenticated against
31648 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
31651 @item @code{allow-downgrades?} (default: @code{#f})
31652 Whether to allow potential downgrades.
31654 Like @command{guix system reconfigure}, @command{guix deploy} compares
31655 the channel commits currently deployed on the remote host (as returned
31656 by @command{guix system describe}) to those currently in use (as
31657 returned by @command{guix describe}) to determine whether commits
31658 currently in use are descendants of those deployed. When this is not
31659 the case and @code{allow-downgrades?} is false, it raises an error.
31660 This ensures you do not accidentally downgrade remote machines.
31664 @deftp {Data Type} digital-ocean-configuration
31665 This is the data type describing the Droplet that should be created for a
31666 machine with an @code{environment} of @code{digital-ocean-environment-type}.
31669 @item @code{ssh-key}
31670 The path to the SSH private key to use to authenticate with the remote
31671 host. In the future, this field may not exist.
31673 A list of string ``tags'' that uniquely identify the machine. Must be given
31674 such that no two machines in the deployment have the same set of tags.
31675 @item @code{region}
31676 A Digital Ocean region slug, such as @code{"nyc3"}.
31678 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
31679 @item @code{enable-ipv6?}
31680 Whether or not the droplet should be created with IPv6 networking.
31684 @node Running Guix in a VM
31685 @section Running Guix in a Virtual Machine
31687 @cindex virtual machine
31688 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM image
31690 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.xz}.
31691 This image is a compressed image in QCOW format. You will first need to
31692 decompress with @command{xz -d}, and then you can pass it to an emulator such
31693 as QEMU (see below for details).
31695 This image boots the Xfce graphical environment and it contains some
31696 commonly used tools. You can install more software in the image by running
31697 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
31698 also reconfigure the system based on its initial configuration file available
31699 as @file{/run/current-system/configuration.scm} (@pxref{Using the
31700 Configuration System}).
31702 Instead of using this pre-built image, one can also build their own virtual
31703 machine image using @command{guix system vm-image} (@pxref{Invoking guix
31704 system}). The returned image is in qcow2 format, which the
31705 @uref{https://qemu.org/, QEMU emulator} can efficiently use.
31708 If you built your own image, you must copy it out of the store
31709 (@pxref{The Store}) and give yourself permission to write to the copy
31710 before you can use it. When invoking QEMU, you must choose a system
31711 emulator that is suitable for your hardware platform. Here is a minimal
31712 QEMU invocation that will boot the result of @command{guix system
31713 vm-image} on x86_64 hardware:
31716 $ qemu-system-x86_64 \
31717 -nic user,model=virtio-net-pci \
31718 -enable-kvm -m 1024 \
31719 -device virtio-blk,drive=myhd \
31720 -drive if=none,file=/tmp/qemu-image,id=myhd
31723 Here is what each of these options means:
31726 @item qemu-system-x86_64
31727 This specifies the hardware platform to emulate. This should match the
31730 @item -nic user,model=virtio-net-pci
31731 Enable the unprivileged user-mode network stack. The guest OS can
31732 access the host but not vice versa. This is the simplest way to get the
31733 guest OS online. @code{model} specifies which network device to emulate:
31734 @code{virtio-net-pci} is a special device made for virtualized operating
31735 systems and recommended for most uses. Assuming your hardware platform is
31736 x86_64, you can get a list of available NIC models by running
31737 @command{qemu-system-x86_64 -nic model=help}.
31740 If your system has hardware virtualization extensions, enabling the
31741 virtual machine support (KVM) of the Linux kernel will make things run
31744 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
31746 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
31747 which may be insufficient for some operations.
31749 @item -device virtio-blk,drive=myhd
31750 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
31751 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
31752 better performance than if it were emulating a complete disk drive. See the
31753 QEMU and KVM documentation for more info.
31755 @item -drive if=none,file=/tmp/qemu-image,id=myhd
31756 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
31757 store of the ``myhd'' drive.
31760 The default @command{run-vm.sh} script that is returned by an invocation of
31761 @command{guix system vm} does not add a @command{-nic user} flag by default.
31762 To get network access from within the vm add the @code{(dhcp-client-service)}
31763 to your system definition and start the VM using
31764 @command{`guix system vm config.scm` -nic user}. An important caveat of using
31765 @command{-nic user} for networking is that @command{ping} will not work, because
31766 it uses the ICMP protocol. You'll have to use a different command to check for
31767 network connectivity, for example @command{guix download}.
31769 @subsection Connecting Through SSH
31773 To enable SSH inside a VM you need to add an SSH server like
31774 @code{openssh-service-type} to your VM (@pxref{Networking Services,
31775 @code{openssh-service-type}}). In addition you need to forward the SSH port,
31776 22 by default, to the host. You can do this with
31779 `guix system vm config.scm` -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
31782 To connect to the VM you can run
31785 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022
31788 The @command{-p} tells @command{ssh} the port you want to connect to.
31789 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
31790 every time you modify your @command{config.scm} file and the
31791 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
31792 connection to an unknown host every time you connect.
31794 @subsection Using @command{virt-viewer} with Spice
31796 As an alternative to the default @command{qemu} graphical client you can
31797 use the @command{remote-viewer} from the @command{virt-viewer} package. To
31798 connect pass the @command{-spice port=5930,disable-ticketing} flag to
31799 @command{qemu}. See previous section for further information on how to do this.
31801 Spice also allows you to do some nice stuff like share your clipboard with your
31802 VM. To enable that you'll also have to pass the following flags to @command{qemu}:
31805 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
31806 -chardev spicevmc,name=vdagent,id=vdagent
31807 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,
31808 name=com.redhat.spice.0
31811 You'll also need to add the @code{(spice-vdagent-service)} to your
31812 system definition (@pxref{Miscellaneous Services, Spice service}).
31814 @node Defining Services
31815 @section Defining Services
31817 The previous sections show the available services and how one can combine
31818 them in an @code{operating-system} declaration. But how do we define
31819 them in the first place? And what is a service anyway?
31822 * Service Composition:: The model for composing services.
31823 * Service Types and Services:: Types and services.
31824 * Service Reference:: API reference.
31825 * Shepherd Services:: A particular type of service.
31828 @node Service Composition
31829 @subsection Service Composition
31833 Here we define a @dfn{service} as, broadly, something that extends the
31834 functionality of the operating system. Often a service is a process---a
31835 @dfn{daemon}---started when the system boots: a secure shell server, a
31836 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
31837 whose execution can be triggered by another daemon---e.g., an FTP server
31838 started by @command{inetd} or a D-Bus service activated by
31839 @command{dbus-daemon}. Occasionally, a service does not map to a
31840 daemon. For instance, the ``account'' service collects user accounts
31841 and makes sure they exist when the system runs; the ``udev'' service
31842 collects device management rules and makes them available to the eudev
31843 daemon; the @file{/etc} service populates the @file{/etc} directory
31846 @cindex service extensions
31847 Guix system services are connected by @dfn{extensions}. For instance, the
31848 secure shell service @emph{extends} the Shepherd---the
31849 initialization system, running as PID@tie{}1---by giving it the command
31850 lines to start and stop the secure shell daemon (@pxref{Networking
31851 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
31852 service by passing it its @file{.service} specification, and extends the
31853 udev service by passing it device management rules (@pxref{Desktop
31854 Services, @code{upower-service}}); the Guix daemon service extends the
31855 Shepherd by passing it the command lines to start and stop the daemon,
31856 and extends the account service by passing it a list of required build
31857 user accounts (@pxref{Base Services}).
31859 All in all, services and their ``extends'' relations form a directed
31860 acyclic graph (DAG). If we represent services as boxes and extensions
31861 as arrows, a typical system might provide something like this:
31863 @image{images/service-graph,,5in,Typical service extension graph.}
31865 @cindex system service
31866 At the bottom, we see the @dfn{system service}, which produces the
31867 directory containing everything to run and boot the system, as returned
31868 by the @command{guix system build} command. @xref{Service Reference},
31869 to learn about the other service types shown here.
31870 @xref{system-extension-graph, the @command{guix system extension-graph}
31871 command}, for information on how to generate this representation for a
31872 particular operating system definition.
31874 @cindex service types
31875 Technically, developers can define @dfn{service types} to express these
31876 relations. There can be any number of services of a given type on the
31877 system---for instance, a system running two instances of the GNU secure
31878 shell server (lsh) has two instances of @code{lsh-service-type}, with
31879 different parameters.
31881 The following section describes the programming interface for service
31882 types and services.
31884 @node Service Types and Services
31885 @subsection Service Types and Services
31887 A @dfn{service type} is a node in the DAG described above. Let us start
31888 with a simple example, the service type for the Guix build daemon
31889 (@pxref{Invoking guix-daemon}):
31892 (define guix-service-type
31896 (list (service-extension shepherd-root-service-type guix-shepherd-service)
31897 (service-extension account-service-type guix-accounts)
31898 (service-extension activation-service-type guix-activation)))
31899 (default-value (guix-configuration))))
31903 It defines three things:
31907 A name, whose sole purpose is to make inspection and debugging easier.
31910 A list of @dfn{service extensions}, where each extension designates the
31911 target service type and a procedure that, given the parameters of the
31912 service, returns a list of objects to extend the service of that type.
31914 Every service type has at least one service extension. The only
31915 exception is the @dfn{boot service type}, which is the ultimate service.
31918 Optionally, a default value for instances of this type.
31921 In this example, @code{guix-service-type} extends three services:
31924 @item shepherd-root-service-type
31925 The @code{guix-shepherd-service} procedure defines how the Shepherd
31926 service is extended. Namely, it returns a @code{<shepherd-service>}
31927 object that defines how @command{guix-daemon} is started and stopped
31928 (@pxref{Shepherd Services}).
31930 @item account-service-type
31931 This extension for this service is computed by @code{guix-accounts},
31932 which returns a list of @code{user-group} and @code{user-account}
31933 objects representing the build user accounts (@pxref{Invoking
31936 @item activation-service-type
31937 Here @code{guix-activation} is a procedure that returns a gexp, which is
31938 a code snippet to run at ``activation time''---e.g., when the service is
31942 A service of this type is instantiated like this:
31945 (service guix-service-type
31946 (guix-configuration
31948 (extra-options '("--gc-keep-derivations"))))
31951 The second argument to the @code{service} form is a value representing
31952 the parameters of this specific service instance.
31953 @xref{guix-configuration-type, @code{guix-configuration}}, for
31954 information about the @code{guix-configuration} data type. When the
31955 value is omitted, the default value specified by
31956 @code{guix-service-type} is used:
31959 (service guix-service-type)
31962 @code{guix-service-type} is quite simple because it extends other
31963 services but is not extensible itself.
31965 @c @subsubsubsection Extensible Service Types
31967 The service type for an @emph{extensible} service looks like this:
31970 (define udev-service-type
31971 (service-type (name 'udev)
31973 (list (service-extension shepherd-root-service-type
31974 udev-shepherd-service)))
31976 (compose concatenate) ;concatenate the list of rules
31977 (extend (lambda (config rules)
31979 (($ <udev-configuration> udev initial-rules)
31980 (udev-configuration
31981 (udev udev) ;the udev package to use
31982 (rules (append initial-rules rules)))))))))
31985 This is the service type for the
31986 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
31987 management daemon}. Compared to the previous example, in addition to an
31988 extension of @code{shepherd-root-service-type}, we see two new fields:
31992 This is the procedure to @dfn{compose} the list of extensions to
31993 services of this type.
31995 Services can extend the udev service by passing it lists of rules; we
31996 compose those extensions simply by concatenating them.
31999 This procedure defines how the value of the service is @dfn{extended} with
32000 the composition of the extensions.
32002 Udev extensions are composed into a list of rules, but the udev service
32003 value is itself a @code{<udev-configuration>} record. So here, we
32004 extend that record by appending the list of rules it contains to the
32005 list of contributed rules.
32008 This is a string giving an overview of the service type. The string can
32009 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
32010 @command{guix system search} command searches these strings and displays
32011 them (@pxref{Invoking guix system}).
32014 There can be only one instance of an extensible service type such as
32015 @code{udev-service-type}. If there were more, the
32016 @code{service-extension} specifications would be ambiguous.
32018 Still here? The next section provides a reference of the programming
32019 interface for services.
32021 @node Service Reference
32022 @subsection Service Reference
32024 We have seen an overview of service types (@pxref{Service Types and
32025 Services}). This section provides a reference on how to manipulate
32026 services and service types. This interface is provided by the
32027 @code{(gnu services)} module.
32029 @deffn {Scheme Procedure} service @var{type} [@var{value}]
32030 Return a new service of @var{type}, a @code{<service-type>} object (see
32031 below). @var{value} can be any object; it represents the parameters of
32032 this particular service instance.
32034 When @var{value} is omitted, the default value specified by @var{type}
32035 is used; if @var{type} does not specify a default value, an error is
32038 For instance, this:
32041 (service openssh-service-type)
32045 is equivalent to this:
32048 (service openssh-service-type
32049 (openssh-configuration))
32052 In both cases the result is an instance of @code{openssh-service-type}
32053 with the default configuration.
32056 @deffn {Scheme Procedure} service? @var{obj}
32057 Return true if @var{obj} is a service.
32060 @deffn {Scheme Procedure} service-kind @var{service}
32061 Return the type of @var{service}---i.e., a @code{<service-type>} object.
32064 @deffn {Scheme Procedure} service-value @var{service}
32065 Return the value associated with @var{service}. It represents its
32069 Here is an example of how a service is created and manipulated:
32073 (service nginx-service-type
32074 (nginx-configuration
32076 (log-directory log-directory)
32077 (run-directory run-directory)
32078 (file config-file))))
32083 (eq? (service-kind s) nginx-service-type)
32087 The @code{modify-services} form provides a handy way to change the
32088 parameters of some of the services of a list such as
32089 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
32090 evaluates to a list of services. Of course, you could always use
32091 standard list combinators such as @code{map} and @code{fold} to do that
32092 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
32093 @code{modify-services} simply provides a more concise form for this
32096 @deffn {Scheme Syntax} modify-services @var{services} @
32097 (@var{type} @var{variable} => @var{body}) @dots{}
32099 Modify the services listed in @var{services} according to the given
32100 clauses. Each clause has the form:
32103 (@var{type} @var{variable} => @var{body})
32106 where @var{type} is a service type---e.g.,
32107 @code{guix-service-type}---and @var{variable} is an identifier that is
32108 bound within the @var{body} to the service parameters---e.g., a
32109 @code{guix-configuration} instance---of the original service of that
32112 The @var{body} should evaluate to the new service parameters, which will
32113 be used to configure the new service. This new service will replace the
32114 original in the resulting list. Because a service's service parameters
32115 are created using @code{define-record-type*}, you can write a succinct
32116 @var{body} that evaluates to the new service parameters by using the
32117 @code{inherit} feature that @code{define-record-type*} provides.
32119 @xref{Using the Configuration System}, for example usage.
32123 Next comes the programming interface for service types. This is
32124 something you want to know when writing new service definitions, but not
32125 necessarily when simply looking for ways to customize your
32126 @code{operating-system} declaration.
32128 @deftp {Data Type} service-type
32129 @cindex service type
32130 This is the representation of a @dfn{service type} (@pxref{Service Types
32135 This is a symbol, used only to simplify inspection and debugging.
32137 @item @code{extensions}
32138 A non-empty list of @code{<service-extension>} objects (see below).
32140 @item @code{compose} (default: @code{#f})
32141 If this is @code{#f}, then the service type denotes services that cannot
32142 be extended---i.e., services that do not receive ``values'' from other
32145 Otherwise, it must be a one-argument procedure. The procedure is called
32146 by @code{fold-services} and is passed a list of values collected from
32147 extensions. It may return any single value.
32149 @item @code{extend} (default: @code{#f})
32150 If this is @code{#f}, services of this type cannot be extended.
32152 Otherwise, it must be a two-argument procedure: @code{fold-services}
32153 calls it, passing it the initial value of the service as the first
32154 argument and the result of applying @code{compose} to the extension
32155 values as the second argument. It must return a value that is a valid
32156 parameter value for the service instance.
32158 @item @code{description}
32159 This is a string, possibly using Texinfo markup, describing in a couple
32160 of sentences what the service is about. This string allows users to
32161 find about the service through @command{guix system search}
32162 (@pxref{Invoking guix system}).
32164 @item @code{default-value} (default: @code{&no-default-value})
32165 The default value associated for instances of this service type. This
32166 allows users to use the @code{service} form without its second argument:
32169 (service @var{type})
32172 The returned service in this case has the default value specified by
32176 @xref{Service Types and Services}, for examples.
32179 @deffn {Scheme Procedure} service-extension @var{target-type} @
32181 Return a new extension for services of type @var{target-type}.
32182 @var{compute} must be a one-argument procedure: @code{fold-services}
32183 calls it, passing it the value associated with the service that provides
32184 the extension; it must return a valid value for the target service.
32187 @deffn {Scheme Procedure} service-extension? @var{obj}
32188 Return true if @var{obj} is a service extension.
32191 Occasionally, you might want to simply extend an existing service. This
32192 involves creating a new service type and specifying the extension of
32193 interest, which can be verbose; the @code{simple-service} procedure
32194 provides a shorthand for this.
32196 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
32197 Return a service that extends @var{target} with @var{value}. This works
32198 by creating a singleton service type @var{name}, of which the returned
32199 service is an instance.
32201 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
32205 (simple-service 'my-mcron-job mcron-service-type
32206 #~(job '(next-hour (3)) "guix gc -F 2G"))
32210 At the core of the service abstraction lies the @code{fold-services}
32211 procedure, which is responsible for ``compiling'' a list of services
32212 down to a single directory that contains everything needed to boot and
32213 run the system---the directory shown by the @command{guix system build}
32214 command (@pxref{Invoking guix system}). In essence, it propagates
32215 service extensions down the service graph, updating each node parameters
32216 on the way, until it reaches the root node.
32218 @deffn {Scheme Procedure} fold-services @var{services} @
32219 [#:target-type @var{system-service-type}]
32220 Fold @var{services} by propagating their extensions down to the root of
32221 type @var{target-type}; return the root service adjusted accordingly.
32224 Lastly, the @code{(gnu services)} module also defines several essential
32225 service types, some of which are listed below.
32227 @defvr {Scheme Variable} system-service-type
32228 This is the root of the service graph. It produces the system directory
32229 as returned by the @command{guix system build} command.
32232 @defvr {Scheme Variable} boot-service-type
32233 The type of the ``boot service'', which produces the @dfn{boot script}.
32234 The boot script is what the initial RAM disk runs when booting.
32237 @defvr {Scheme Variable} etc-service-type
32238 The type of the @file{/etc} service. This service is used to create
32239 files under @file{/etc} and can be extended by
32240 passing it name/file tuples such as:
32243 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
32246 In this example, the effect would be to add an @file{/etc/issue} file
32247 pointing to the given file.
32250 @defvr {Scheme Variable} setuid-program-service-type
32251 Type for the ``setuid-program service''. This service collects lists of
32252 executable file names, passed as gexps, and adds them to the set of
32253 setuid-root programs on the system (@pxref{Setuid Programs}).
32256 @defvr {Scheme Variable} profile-service-type
32257 Type of the service that populates the @dfn{system profile}---i.e., the
32258 programs under @file{/run/current-system/profile}. Other services can
32259 extend it by passing it lists of packages to add to the system profile.
32262 @cindex provenance tracking, of the operating system
32263 @anchor{provenance-service-type}
32264 @defvr {Scheme Variable} provenance-service-type
32265 This is the type of the service that records @dfn{provenance meta-data}
32266 in the system itself. It creates several files under
32267 @file{/run/current-system}:
32271 This is a ``channel file'' that can be passed to @command{guix pull -C}
32272 or @command{guix time-machine -C}, and which describes the channels used
32273 to build the system, if that information was available
32274 (@pxref{Channels}).
32276 @item configuration.scm
32277 This is the file that was passed as the value for this
32278 @code{provenance-service-type} service. By default, @command{guix
32279 system reconfigure} automatically passes the OS configuration file it
32280 received on the command line.
32283 This contains the same information as the two other files but in a
32284 format that is more readily processable.
32287 In general, these two pieces of information (channels and configuration
32288 file) are enough to reproduce the operating system ``from source''.
32291 This information is necessary to rebuild your operating system, but it
32292 is not always sufficient. In particular, @file{configuration.scm}
32293 itself is insufficient if it is not self-contained---if it refers to
32294 external Guile modules or to extra files. If you want
32295 @file{configuration.scm} to be self-contained, we recommend that modules
32296 or files it refers to be part of a channel.
32298 Besides, provenance meta-data is ``silent'' in the sense that it does
32299 not change the bits contained in your system, @emph{except for the
32300 meta-data bits themselves}. Two different OS configurations or sets of
32301 channels can lead to the same system, bit-for-bit; when
32302 @code{provenance-service-type} is used, these two systems will have
32303 different meta-data and thus different store file names, which makes
32304 comparison less trivial.
32307 This service is automatically added to your operating system
32308 configuration when you use @command{guix system reconfigure},
32309 @command{guix system init}, or @command{guix deploy}.
32312 @node Shepherd Services
32313 @subsection Shepherd Services
32315 @cindex shepherd services
32317 @cindex init system
32318 The @code{(gnu services shepherd)} module provides a way to define
32319 services managed by the GNU@tie{}Shepherd, which is the
32320 initialization system---the first process that is started when the
32321 system boots, also known as PID@tie{}1
32322 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
32324 Services in the Shepherd can depend on each other. For instance, the
32325 SSH daemon may need to be started after the syslog daemon has been
32326 started, which in turn can only happen once all the file systems have
32327 been mounted. The simple operating system defined earlier (@pxref{Using
32328 the Configuration System}) results in a service graph like this:
32330 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
32332 You can actually generate such a graph for any operating system
32333 definition using the @command{guix system shepherd-graph} command
32334 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
32336 The @code{%shepherd-root-service} is a service object representing
32337 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
32338 by passing it lists of @code{<shepherd-service>} objects.
32340 @deftp {Data Type} shepherd-service
32341 The data type representing a service managed by the Shepherd.
32344 @item @code{provision}
32345 This is a list of symbols denoting what the service provides.
32347 These are the names that may be passed to @command{herd start},
32348 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
32349 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
32350 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
32352 @item @code{requirement} (default: @code{'()})
32353 List of symbols denoting the Shepherd services this one depends on.
32355 @cindex one-shot services, for the Shepherd
32356 @item @code{one-shot?} (default: @code{#f})
32357 Whether this service is @dfn{one-shot}. One-shot services stop immediately
32358 after their @code{start} action has completed. @xref{Slots of services,,,
32359 shepherd, The GNU Shepherd Manual}, for more info.
32361 @item @code{respawn?} (default: @code{#t})
32362 Whether to restart the service when it stops, for instance when the
32363 underlying process dies.
32366 @itemx @code{stop} (default: @code{#~(const #f)})
32367 The @code{start} and @code{stop} fields refer to the Shepherd's
32368 facilities to start and stop processes (@pxref{Service De- and
32369 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
32370 G-expressions that get expanded in the Shepherd configuration file
32371 (@pxref{G-Expressions}).
32373 @item @code{actions} (default: @code{'()})
32374 @cindex actions, of Shepherd services
32375 This is a list of @code{shepherd-action} objects (see below) defining
32376 @dfn{actions} supported by the service, in addition to the standard
32377 @code{start} and @code{stop} actions. Actions listed here become available as
32378 @command{herd} sub-commands:
32381 herd @var{action} @var{service} [@var{arguments}@dots{}]
32384 @item @code{auto-start?} (default: @code{#t})
32385 Whether this service should be started automatically by the Shepherd. If it
32386 is @code{#f} the service has to be started manually with @code{herd start}.
32388 @item @code{documentation}
32389 A documentation string, as shown when running:
32392 herd doc @var{service-name}
32395 where @var{service-name} is one of the symbols in @code{provision}
32396 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
32398 @item @code{modules} (default: @code{%default-modules})
32399 This is the list of modules that must be in scope when @code{start} and
32400 @code{stop} are evaluated.
32405 @deftp {Data Type} shepherd-action
32406 This is the data type that defines additional actions implemented by a
32407 Shepherd service (see above).
32411 Symbol naming the action.
32413 @item documentation
32414 This is a documentation string for the action. It can be viewed by running:
32417 herd doc @var{service} action @var{action}
32421 This should be a gexp that evaluates to a procedure of at least one argument,
32422 which is the ``running value'' of the service (@pxref{Slots of services,,,
32423 shepherd, The GNU Shepherd Manual}).
32426 The following example defines an action called @code{say-hello} that kindly
32432 (documentation "Say hi!")
32433 (procedure #~(lambda (running . args)
32434 (format #t "Hello, friend! arguments: ~s\n"
32439 Assuming this action is added to the @code{example} service, then you can do:
32442 # herd say-hello example
32443 Hello, friend! arguments: ()
32444 # herd say-hello example a b c
32445 Hello, friend! arguments: ("a" "b" "c")
32448 This, as you can see, is a fairly sophisticated way to say hello.
32449 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
32453 @defvr {Scheme Variable} shepherd-root-service-type
32454 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
32456 This is the service type that extensions target when they want to create
32457 shepherd services (@pxref{Service Types and Services}, for an example).
32458 Each extension must pass a list of @code{<shepherd-service>}.
32461 @defvr {Scheme Variable} %shepherd-root-service
32462 This service represents PID@tie{}1.
32466 @node Documentation
32467 @chapter Documentation
32469 @cindex documentation, searching for
32470 @cindex searching for documentation
32471 @cindex Info, documentation format
32473 @cindex manual pages
32474 In most cases packages installed with Guix come with documentation.
32475 There are two main documentation formats: ``Info'', a browseable
32476 hypertext format used for GNU software, and ``manual pages'' (or ``man
32477 pages''), the linear documentation format traditionally found on Unix.
32478 Info manuals are accessed with the @command{info} command or with Emacs,
32479 and man pages are accessed using @command{man}.
32481 You can look for documentation of software installed on your system by
32482 keyword. For example, the following command searches for information
32483 about ``TLS'' in Info manuals:
32487 "(emacs)Network Security" -- STARTTLS
32488 "(emacs)Network Security" -- TLS
32489 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
32490 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
32495 The command below searches for the same keyword in man pages:
32499 SSL (7) - OpenSSL SSL/TLS library
32500 certtool (1) - GnuTLS certificate tool
32504 These searches are purely local to your computer so you have the
32505 guarantee that documentation you find corresponds to what you have
32506 actually installed, you can access it off-line, and your privacy is
32509 Once you have these results, you can view the relevant documentation by
32513 $ info "(gnutls)Core TLS API"
32523 Info manuals contain sections and indices as well as hyperlinks like
32524 those found in Web pages. The @command{info} reader (@pxref{Top, Info
32525 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
32526 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
32527 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
32528 Introduction}, for an introduction to Info navigation.
32530 @node Installing Debugging Files
32531 @chapter Installing Debugging Files
32533 @cindex debugging files
32534 Program binaries, as produced by the GCC compilers for instance, are
32535 typically written in the ELF format, with a section containing
32536 @dfn{debugging information}. Debugging information is what allows the
32537 debugger, GDB, to map binary code to source code; it is required to
32538 debug a compiled program in good conditions.
32540 This chapter explains how to use separate debug info when packages
32541 provide it, and how to rebuild packages with debug info when it's
32545 * Separate Debug Info:: Installing 'debug' outputs.
32546 * Rebuilding Debug Info:: Building missing debug info.
32549 @node Separate Debug Info
32550 @section Separate Debug Info
32552 The problem with debugging information is that is takes up a fair amount
32553 of disk space. For example, debugging information for the GNU C Library
32554 weighs in at more than 60 MiB. Thus, as a user, keeping all the
32555 debugging info of all the installed programs is usually not an option.
32556 Yet, space savings should not come at the cost of an impediment to
32557 debugging---especially in the GNU system, which should make it easier
32558 for users to exert their computing freedom (@pxref{GNU Distribution}).
32560 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
32561 mechanism that allows users to get the best of both worlds: debugging
32562 information can be stripped from the binaries and stored in separate
32563 files. GDB is then able to load debugging information from those files,
32564 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
32567 The GNU distribution takes advantage of this by storing debugging
32568 information in the @code{lib/debug} sub-directory of a separate package
32569 output unimaginatively called @code{debug} (@pxref{Packages with
32570 Multiple Outputs}). Users can choose to install the @code{debug} output
32571 of a package when they need it. For instance, the following command
32572 installs the debugging information for the GNU C Library and for GNU
32576 guix install glibc:debug guile:debug
32579 GDB must then be told to look for debug files in the user's profile, by
32580 setting the @code{debug-file-directory} variable (consider setting it
32581 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
32585 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
32588 From there on, GDB will pick up debugging information from the
32589 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
32591 In addition, you will most likely want GDB to be able to show the source
32592 code being debugged. To do that, you will have to unpack the source
32593 code of the package of interest (obtained with @code{guix build
32594 --source}, @pxref{Invoking guix build}), and to point GDB to that source
32595 directory using the @code{directory} command (@pxref{Source Path,
32596 @code{directory},, gdb, Debugging with GDB}).
32598 @c XXX: keep me up-to-date
32599 The @code{debug} output mechanism in Guix is implemented by the
32600 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
32601 opt-in---debugging information is available only for the packages with
32602 definitions explicitly declaring a @code{debug} output. To check
32603 whether a package has a @code{debug} output, use @command{guix package
32604 --list-available} (@pxref{Invoking guix package}).
32606 Read on for how to deal with packages lacking a @code{debug} output.
32608 @node Rebuilding Debug Info
32609 @section Rebuilding Debug Info
32611 @cindex debugging info, rebuilding
32612 As we saw above, some packages, but not all, provide debugging info in a
32613 @code{debug} output. What can you do when debugging info is missing?
32614 The @option{--with-debug-info} option provides a solution to that: it
32615 allows you to rebuild the package(s) for which debugging info is
32616 missing---and only those---and to graft those onto the application
32617 you're debugging. Thus, while it's not as fast as installing a
32618 @code{debug} output, it is relatively inexpensive.
32620 Let's illustrate that. Suppose you're experiencing a bug in Inkscape
32621 and would like to see what's going on in GLib, a library that's deep
32622 down in its dependency graph. As it turns out, GLib does not have a
32623 @code{debug} output and the backtrace GDB shows is all sadness:
32627 #0 0x00007ffff5f92190 in g_getenv ()
32628 from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
32629 #1 0x00007ffff608a7d6 in gobject_init_ctor ()
32630 from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
32631 #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
32632 env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
32633 #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
32637 To address that, you install Inkscape linked against a variant GLib that
32638 contains debug info:
32641 guix install inkscape --with-debug-info=glib
32644 This time, debugging will be a whole lot nicer:
32647 $ gdb --args sh -c 'exec inkscape'
32650 Function "g_getenv" not defined.
32651 Make breakpoint pending on future shared library load? (y or [n]) y
32652 Breakpoint 1 (g_getenv) pending.
32654 Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
32657 #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
32658 #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
32659 #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
32660 #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
32661 env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
32667 Note that there can be packages for which @option{--with-debug-info}
32668 will not have the desired effect. @xref{Package Transformation Options,
32669 @option{--with-debug-info}}, for more information.
32671 @node Security Updates
32672 @chapter Security Updates
32674 @cindex security updates
32675 @cindex security vulnerabilities
32676 Occasionally, important security vulnerabilities are discovered in software
32677 packages and must be patched. Guix developers try hard to keep track of
32678 known vulnerabilities and to apply fixes as soon as possible in the
32679 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
32680 containing only security updates). The @command{guix lint} tool helps
32681 developers find out about vulnerable versions of software packages in the
32686 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
32687 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
32688 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
32692 @xref{Invoking guix lint}, for more information.
32694 Guix follows a functional
32695 package management discipline (@pxref{Introduction}), which implies
32696 that, when a package is changed, @emph{every package that depends on it}
32697 must be rebuilt. This can significantly slow down the deployment of
32698 fixes in core packages such as libc or Bash, since basically the whole
32699 distribution would need to be rebuilt. Using pre-built binaries helps
32700 (@pxref{Substitutes}), but deployment may still take more time than
32704 To address this, Guix implements @dfn{grafts}, a mechanism that allows
32705 for fast deployment of critical updates without the costs associated
32706 with a whole-distribution rebuild. The idea is to rebuild only the
32707 package that needs to be patched, and then to ``graft'' it onto packages
32708 explicitly installed by the user and that were previously referring to
32709 the original package. The cost of grafting is typically very low, and
32710 order of magnitudes lower than a full rebuild of the dependency chain.
32712 @cindex replacements of packages, for grafts
32713 For instance, suppose a security update needs to be applied to Bash.
32714 Guix developers will provide a package definition for the ``fixed''
32715 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
32716 Packages}). Then, the original package definition is augmented with a
32717 @code{replacement} field pointing to the package containing the bug fix:
32724 (replacement bash-fixed)))
32727 From there on, any package depending directly or indirectly on Bash---as
32728 reported by @command{guix gc --requisites} (@pxref{Invoking guix
32729 gc})---that is installed is automatically ``rewritten'' to refer to
32730 @code{bash-fixed} instead of @code{bash}. This grafting process takes
32731 time proportional to the size of the package, usually less than a
32732 minute for an ``average'' package on a recent machine. Grafting is
32733 recursive: when an indirect dependency requires grafting, then grafting
32734 ``propagates'' up to the package that the user is installing.
32736 Currently, the length of the name and version of the graft and that of
32737 the package it replaces (@code{bash-fixed} and @code{bash} in the example
32738 above) must be equal. This restriction mostly comes from the fact that
32739 grafting works by patching files, including binary files, directly.
32740 Other restrictions may apply: for instance, when adding a graft to a
32741 package providing a shared library, the original shared library and its
32742 replacement must have the same @code{SONAME} and be binary-compatible.
32744 The @option{--no-grafts} command-line option allows you to forcefully
32745 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
32749 guix build bash --no-grafts
32753 returns the store file name of the original Bash, whereas:
32760 returns the store file name of the ``fixed'', replacement Bash. This
32761 allows you to distinguish between the two variants of Bash.
32763 To verify which Bash your whole profile refers to, you can run
32764 (@pxref{Invoking guix gc}):
32767 guix gc -R `readlink -f ~/.guix-profile` | grep bash
32771 @dots{} and compare the store file names that you get with those above.
32772 Likewise for a complete Guix system generation:
32775 guix gc -R `guix system build my-config.scm` | grep bash
32778 Lastly, to check which Bash running processes are using, you can use the
32779 @command{lsof} command:
32782 lsof | grep /gnu/store/.*bash
32786 @node Bootstrapping
32787 @chapter Bootstrapping
32789 @c Adapted from the ELS 2013 paper.
32791 @cindex bootstrapping
32793 Bootstrapping in our context refers to how the distribution gets built
32794 ``from nothing''. Remember that the build environment of a derivation
32795 contains nothing but its declared inputs (@pxref{Introduction}). So
32796 there's an obvious chicken-and-egg problem: how does the first package
32797 get built? How does the first compiler get compiled?
32799 It is tempting to think of this question as one that only die-hard
32800 hackers may care about. However, while the answer to that question is
32801 technical in nature, its implications are wide-ranging. How the
32802 distribution is bootstrapped defines the extent to which we, as
32803 individuals and as a collective of users and hackers, can trust the
32804 software we run. It is a central concern from the standpoint of
32805 @emph{security} and from a @emph{user freedom} viewpoint.
32807 @cindex bootstrap binaries
32808 The GNU system is primarily made of C code, with libc at its core. The
32809 GNU build system itself assumes the availability of a Bourne shell and
32810 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
32811 `grep'. Furthermore, build programs---programs that run
32812 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
32813 (@pxref{Derivations}). Consequently, to be able to build anything at
32814 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
32815 Binutils, libc, and the other packages mentioned above---the
32816 @dfn{bootstrap binaries}.
32818 These bootstrap binaries are ``taken for granted'', though we can also
32819 re-create them if needed (@pxref{Preparing to Use the Bootstrap
32823 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
32824 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
32827 @node Reduced Binary Seed Bootstrap
32828 @section The Reduced Binary Seed Bootstrap
32830 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
32831 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
32832 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
32833 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
32834 ``taken for granted.''
32836 Taking the bootstrap binaries for granted means that we consider them to
32837 be a correct and trustworthy ``seed'' for building the complete system.
32838 Therein lies a problem: the combined size of these bootstrap binaries is
32839 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
32840 or even inspecting these is next to impossible.
32842 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
32843 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
32844 Source Bootstrap'' and while we are working towards that goal it would
32845 be hyperbole to use that term for what we do now.}.
32847 The Reduced Binary Seed bootstrap removes the most critical tools---from a
32848 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
32849 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
32850 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
32851 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
32853 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
32854 C Library are built from source. From here on the more traditional
32855 bootstrap process resumes. This approach has reduced the bootstrap
32856 binaries in size to about 145MB in Guix v1.1.
32858 The next step that Guix has taken is to replace the shell and all its
32859 utilities with implementations in Guile Scheme, the @emph{Scheme-only
32860 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
32861 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
32862 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
32863 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
32864 removed are now built from source.
32866 Building the GNU System from source is currently only possibly by adding
32867 some historical GNU packages as intermediate steps@footnote{Packages
32868 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
32869 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
32870 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
32871 and GNU packages become more bootstrappable again (e.g., new releases of
32872 GNU Sed will also ship as gzipped tarballs again, as alternative to the
32873 hard to bootstrap @code{xz}-compression), this set of added packages can
32874 hopefully be reduced again.
32876 The graph below shows the resulting dependency graph for
32877 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
32878 traditional bootstrap of the rest of the Guix System.
32880 @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
32881 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
32883 The only significant binary bootstrap seeds that remain@footnote{
32884 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
32885 together with @code{mes}.} are a Scheme intepreter and a Scheme
32886 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
32887 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
32888 to get Guile running.}.
32890 This further reduction has brought down the size of the binary seed to
32891 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
32893 Work is ongoing to remove all binary blobs from our free software
32894 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
32895 is work to bring these bootstraps to the @code{arm-linux} and
32896 @code{aarch64-linux} architectures and to the Hurd.
32898 If you are interested, join us on @samp{#bootstrappable} on the Freenode
32899 IRC network or discuss on @email{bug-mes@@gnu.org} or
32900 @email{gash-devel@@nongnu.org}.
32902 @node Preparing to Use the Bootstrap Binaries
32903 @section Preparing to Use the Bootstrap Binaries
32905 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
32906 @c large image, it's hard to scroll. Oh well.
32907 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
32909 The figure above shows the very beginning of the dependency graph of the
32910 distribution, corresponding to the package definitions of the @code{(gnu
32911 packages bootstrap)} module. A similar figure can be generated with
32912 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
32915 guix graph -t derivation \
32916 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
32917 | dot -Tps > gcc.ps
32920 or, for the further Reduced Binary Seed bootstrap
32923 guix graph -t derivation \
32924 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
32925 | dot -Tps > mes.ps
32928 At this level of detail, things are
32929 slightly complex. First, Guile itself consists of an ELF executable,
32930 along with many source and compiled Scheme files that are dynamically
32931 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
32932 tarball shown in this graph. This tarball is part of Guix's ``source''
32933 distribution, and gets inserted into the store with @code{add-to-store}
32934 (@pxref{The Store}).
32936 But how do we write a derivation that unpacks this tarball and adds it
32937 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
32938 derivation---the first one that gets built---uses @code{bash} as its
32939 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
32940 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
32941 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
32942 the Guix source distribution, whose sole purpose is to allow the Guile
32943 tarball to be unpacked.
32945 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
32946 Guile that can be used to run subsequent build programs. Its first task
32947 is to download tarballs containing the other pre-built binaries---this
32948 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
32949 @code{ftp-client.scm} are used for this purpose. The
32950 @code{module-import.drv} derivations import those modules in a directory
32951 in the store, using the original layout. The
32952 @code{module-import-compiled.drv} derivations compile those modules, and
32953 write them in an output directory with the right layout. This
32954 corresponds to the @code{#:modules} argument of
32955 @code{build-expression->derivation} (@pxref{Derivations}).
32957 Finally, the various tarballs are unpacked by the derivations
32958 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
32959 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
32960 point we have a working C tool chain.
32962 @unnumberedsec Building the Build Tools
32964 Bootstrapping is complete when we have a full tool chain that does not
32965 depend on the pre-built bootstrap tools discussed above. This
32966 no-dependency requirement is verified by checking whether the files of
32967 the final tool chain contain references to the @file{/gnu/store}
32968 directories of the bootstrap inputs. The process that leads to this
32969 ``final'' tool chain is described by the package definitions found in
32970 the @code{(gnu packages commencement)} module.
32972 The @command{guix graph} command allows us to ``zoom out'' compared to
32973 the graph above, by looking at the level of package objects instead of
32974 individual derivations---remember that a package may translate to
32975 several derivations, typically one derivation to download its source,
32976 one to build the Guile modules it needs, and one to actually build the
32977 package from source. The command:
32980 guix graph -t bag \
32981 -e '(@@@@ (gnu packages commencement)
32982 glibc-final-with-bootstrap-bash)' | xdot -
32986 displays the dependency graph leading to the ``final'' C
32987 library@footnote{You may notice the @code{glibc-intermediate} label,
32988 suggesting that it is not @emph{quite} final, but as a good
32989 approximation, we will consider it final.}, depicted below.
32991 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
32993 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
32994 The first tool that gets built with the bootstrap binaries is
32995 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
32996 for all the following packages. From there Findutils and Diffutils get
32999 Then come the first-stage Binutils and GCC, built as pseudo cross
33000 tools---i.e., with @option{--target} equal to @option{--host}. They are
33001 used to build libc. Thanks to this cross-build trick, this libc is
33002 guaranteed not to hold any reference to the initial tool chain.
33004 From there the final Binutils and GCC (not shown above) are built. GCC
33005 uses @command{ld} from the final Binutils, and links programs against
33006 the just-built libc. This tool chain is used to build the other
33007 packages used by Guix and by the GNU Build System: Guile, Bash,
33010 And voilà! At this point we have the complete set of build tools that
33011 the GNU Build System expects. These are in the @code{%final-inputs}
33012 variable of the @code{(gnu packages commencement)} module, and are
33013 implicitly used by any package that uses @code{gnu-build-system}
33014 (@pxref{Build Systems, @code{gnu-build-system}}).
33017 @unnumberedsec Building the Bootstrap Binaries
33019 @cindex bootstrap binaries
33020 Because the final tool chain does not depend on the bootstrap binaries,
33021 those rarely need to be updated. Nevertheless, it is useful to have an
33022 automated way to produce them, should an update occur, and this is what
33023 the @code{(gnu packages make-bootstrap)} module provides.
33025 The following command builds the tarballs containing the bootstrap binaries
33026 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
33027 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
33028 and Guile, and a tarball containing a mixture of Coreutils and other basic
33029 command-line tools):
33032 guix build bootstrap-tarballs
33035 The generated tarballs are those that should be referred to in the
33036 @code{(gnu packages bootstrap)} module mentioned at the beginning of
33039 Still here? Then perhaps by now you've started to wonder: when do we
33040 reach a fixed point? That is an interesting question! The answer is
33041 unknown, but if you would like to investigate further (and have
33042 significant computational and storage resources to do so), then let us
33045 @unnumberedsec Reducing the Set of Bootstrap Binaries
33047 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
33048 binary code! Why is that a problem? It's a problem because these big chunks
33049 of binary code are practically non-auditable, which makes it hard to establish
33050 what source code produced them. Every unauditable binary also leaves us
33051 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
33052 paper @emph{Reflections on Trusting Trust}.
33054 This is mitigated by the fact that our bootstrap binaries were generated
33055 from an earlier Guix revision. Nevertheless it lacks the level of
33056 transparency that we get in the rest of the package dependency graph,
33057 where Guix always gives us a source-to-binary mapping. Thus, our goal
33058 is to reduce the set of bootstrap binaries to the bare minimum.
33060 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
33061 on-going projects to do that. One of these is about replacing the
33062 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
33063 of increasing complexity, which could be built from source starting from
33064 a simple and auditable assembler.
33066 Our first major achievement is the replacement of of GCC, the GNU C Library
33067 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
33068 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
33069 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
33070 bootstrapped yet and thus we inject them as binary seeds. We call this the
33071 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
33072 binaries! Also, it has eliminated the C compiler binary; i686-linux and
33073 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
33075 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
33076 also looking at any other bootstrap binaries. Your help is welcome!
33079 @chapter Porting to a New Platform
33081 As discussed above, the GNU distribution is self-contained, and
33082 self-containment is achieved by relying on pre-built ``bootstrap
33083 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
33084 operating system kernel, CPU architecture, and application binary
33085 interface (ABI). Thus, to port the distribution to a platform that is
33086 not yet supported, one must build those bootstrap binaries, and update
33087 the @code{(gnu packages bootstrap)} module to use them on that platform.
33089 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
33090 When everything goes well, and assuming the GNU tool chain supports the
33091 target platform, this can be as simple as running a command like this
33095 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
33098 For this to work, the @code{glibc-dynamic-linker} procedure in
33099 @code{(gnu packages bootstrap)} must be augmented to return the right
33100 file name for libc's dynamic linker on that platform; likewise,
33101 @code{system->linux-architecture} in @code{(gnu packages linux)} must be
33102 taught about the new platform.
33104 Once these are built, the @code{(gnu packages bootstrap)} module needs
33105 to be updated to refer to these binaries on the target platform. That
33106 is, the hashes and URLs of the bootstrap tarballs for the new platform
33107 must be added alongside those of the currently supported platforms. The
33108 bootstrap Guile tarball is treated specially: it is expected to be
33109 available locally, and @file{gnu/local.mk} has rules to download it for
33110 the supported architectures; a rule for the new platform must be added
33113 In practice, there may be some complications. First, it may be that the
33114 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
33115 above) is not recognized by all the GNU tools. Typically, glibc
33116 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
33117 configure flag (see @code{gcc.scm} for examples of how to handle this).
33118 Second, some of the required packages could fail to build for that
33119 platform. Lastly, the generated binaries could be broken for some
33122 @c *********************************************************************
33123 @include contributing.texi
33125 @c *********************************************************************
33126 @node Acknowledgments
33127 @chapter Acknowledgments
33129 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
33130 which was designed and
33131 implemented by Eelco Dolstra, with contributions from other people (see
33132 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
33133 management, and promoted unprecedented features, such as transactional
33134 package upgrades and rollbacks, per-user profiles, and referentially
33135 transparent build processes. Without this work, Guix would not exist.
33137 The Nix-based software distributions, Nixpkgs and NixOS, have also been
33138 an inspiration for Guix.
33140 GNU@tie{}Guix itself is a collective work with contributions from a
33141 number of people. See the @file{AUTHORS} file in Guix for more
33142 information on these fine people. The @file{THANKS} file lists people
33143 who have helped by reporting bugs, taking care of the infrastructure,
33144 providing artwork and themes, making suggestions, and more---thank you!
33147 @c *********************************************************************
33148 @node GNU Free Documentation License
33149 @appendix GNU Free Documentation License
33150 @cindex license, GNU Free Documentation License
33151 @include fdl-1.3.texi
33153 @c *********************************************************************
33154 @node Concept Index
33155 @unnumbered Concept Index
33158 @node Programming Index
33159 @unnumbered Programming Index
33160 @syncodeindex tp fn
33161 @syncodeindex vr fn
33166 @c Local Variables:
33167 @c ispell-local-dictionary: "american";