6 @documentencoding UTF-8
7 @settitle GNU Guix Reference Manual
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25 Copyright @copyright{} 2012-2022 Ludovic Courtès@*
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110 Permission is granted to copy, distribute and/or modify this document
111 under the terms of the GNU Free Documentation License, Version 1.3 or
112 any later version published by the Free Software Foundation; with no
113 Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A
114 copy of the license is included in the section entitled ``GNU Free
115 Documentation License''.
118 @dircategory System administration
120 * Guix: (guix). Manage installed software and system configuration.
121 * guix package: (guix)Invoking guix package. Installing, removing, and upgrading packages.
122 * guix gc: (guix)Invoking guix gc. Reclaiming unused disk space.
123 * guix pull: (guix)Invoking guix pull. Update the list of available packages.
124 * guix system: (guix)Invoking guix system. Manage the operating system configuration.
125 * guix deploy: (guix)Invoking guix deploy. Manage operating system configurations for remote hosts.
128 @dircategory Software development
130 * guix shell: (guix)Invoking guix shell. Creating software environments.
131 * guix environment: (guix)Invoking guix environment. Building development environments with Guix.
132 * guix build: (guix)Invoking guix build. Building packages.
133 * guix pack: (guix)Invoking guix pack. Creating binary bundles.
137 @title GNU Guix Reference Manual
138 @subtitle Using the GNU Guix Functional Package Manager
139 @author The GNU Guix Developers
142 @vskip 0pt plus 1filll
143 Edition @value{EDITION} @*
151 @c *********************************************************************
155 This document describes GNU Guix version @value{VERSION}, a functional
156 package management tool written for the GNU system.
158 @c TRANSLATORS: You can replace the following paragraph with information on
159 @c how to join your own translation team and how to report issues with the
161 This manual is also available in Simplified Chinese (@pxref{Top,,, guix.zh_CN,
162 GNU Guix参考手册}), French (@pxref{Top,,, guix.fr, Manuel de référence de GNU
163 Guix}), German (@pxref{Top,,, guix.de, Referenzhandbuch zu GNU Guix}),
164 Spanish (@pxref{Top,,, guix.es, Manual de referencia de GNU Guix}), and
165 Russian (@pxref{Top,,, guix.ru, Руководство GNU Guix}). If you
166 would like to translate it in your native language, consider joining
167 @uref{https://translate.fedoraproject.org/projects/guix/documentation-manual,
168 Weblate} (@pxref{Translating Guix}).
171 * Introduction:: What is Guix about?
172 * Installation:: Installing Guix.
173 * System Installation:: Installing the whole operating system.
174 * System Troubleshooting Tips:: When things don't go as planned.
175 * Getting Started:: Your first steps.
176 * Package Management:: Package installation, upgrade, etc.
177 * Channels:: Customizing the package collection.
178 * Development:: Guix-aided software development.
179 * Programming Interface:: Using Guix in Scheme.
180 * Utilities:: Package management commands.
181 * Foreign Architectures:: Build for foreign architectures.
182 * System Configuration:: Configuring the operating system.
183 * Home Configuration:: Configuring the home environment.
184 * Documentation:: Browsing software user manuals.
185 * Installing Debugging Files:: Feeding the debugger.
186 * Using TeX and LaTeX:: Typesetting.
187 * Security Updates:: Deploying security fixes quickly.
188 * Bootstrapping:: GNU/Linux built from scratch.
189 * Porting:: Targeting another platform or kernel.
190 * Contributing:: Your help needed!
192 * Acknowledgments:: Thanks!
193 * GNU Free Documentation License:: The license of this manual.
194 * Concept Index:: Concepts.
195 * Programming Index:: Data types, functions, and variables.
198 --- The Detailed Node Listing ---
202 * Managing Software the Guix Way:: What's special.
203 * GNU Distribution:: The packages and tools.
207 * Binary Installation:: Getting Guix running in no time!
208 * Requirements:: Software needed to build and run Guix.
209 * Running the Test Suite:: Testing Guix.
210 * Setting Up the Daemon:: Preparing the build daemon's environment.
211 * Invoking guix-daemon:: Running the build daemon.
212 * Application Setup:: Application-specific setup.
213 * Upgrading Guix:: Upgrading Guix and its build daemon.
215 Setting Up the Daemon
217 * Build Environment Setup:: Preparing the isolated build environment.
218 * Daemon Offload Setup:: Offloading builds to remote machines.
219 * SELinux Support:: Using an SELinux policy for the daemon.
223 * Limitations:: What you can expect.
224 * Hardware Considerations:: Supported hardware.
225 * USB Stick and DVD Installation:: Preparing the installation medium.
226 * Preparing for Installation:: Networking, partitioning, etc.
227 * Guided Graphical Installation:: Easy graphical installation.
228 * Manual Installation:: Manual installation for wizards.
229 * After System Installation:: When installation succeeded.
230 * Installing Guix in a VM:: Guix System playground.
231 * Building the Installation Image:: How this comes to be.
233 System Troubleshooting Tips
235 * Chrooting into an existing system:: Fixing things from a chroot
239 * Keyboard Layout and Networking and Partitioning:: Initial setup.
240 * Proceeding with the Installation:: Installing.
244 * Features:: How Guix will make your life brighter.
245 * Invoking guix package:: Package installation, removal, etc.
246 * Substitutes:: Downloading pre-built binaries.
247 * Packages with Multiple Outputs:: Single source package, multiple outputs.
248 * Invoking guix gc:: Running the garbage collector.
249 * Invoking guix pull:: Fetching the latest Guix and distribution.
250 * Invoking guix time-machine:: Running an older revision of Guix.
251 * Inferiors:: Interacting with another revision of Guix.
252 * Invoking guix describe:: Display information about your Guix revision.
253 * Invoking guix archive:: Exporting and importing store files.
257 * Official Substitute Servers:: One particular source of substitutes.
258 * Substitute Server Authorization:: How to enable or disable substitutes.
259 * Getting Substitutes from Other Servers:: Substitute diversity.
260 * Substitute Authentication:: How Guix verifies substitutes.
261 * Proxy Settings:: How to get substitutes via proxy.
262 * Substitution Failure:: What happens when substitution fails.
263 * On Trusting Binaries:: How can you trust that binary blob?
267 * Specifying Additional Channels:: Extending the package collection.
268 * Using a Custom Guix Channel:: Using a customized Guix.
269 * Replicating Guix:: Running the @emph{exact same} Guix.
270 * Channel Authentication:: How Guix verifies what it fetches.
271 * Channels with Substitutes:: Using channels with available substitutes.
272 * Creating a Channel:: How to write your custom channel.
273 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
274 * Declaring Channel Dependencies:: How to depend on other channels.
275 * Specifying Channel Authorizations:: Defining channel authors authorizations.
276 * Primary URL:: Distinguishing mirror to original.
277 * Writing Channel News:: Communicating information to channel's users.
281 * Invoking guix shell:: Spawning one-off software environments.
282 * Invoking guix environment:: Setting up development environments.
283 * Invoking guix pack:: Creating software bundles.
284 * The GCC toolchain:: Working with languages supported by GCC.
285 * Invoking guix git authenticate:: Authenticating Git repositories.
287 Programming Interface
289 * Package Modules:: Packages from the programmer's viewpoint.
290 * Defining Packages:: Defining new packages.
291 * Defining Package Variants:: Customizing packages.
292 * Writing Manifests:: The bill of materials of your environment.
293 * Build Systems:: Specifying how packages are built.
294 * Build Phases:: Phases of the build process of a package.
295 * Build Utilities:: Helpers for your package definitions and more.
296 * Search Paths:: Declaring search path environment variables.
297 * The Store:: Manipulating the package store.
298 * Derivations:: Low-level interface to package derivations.
299 * The Store Monad:: Purely functional interface to the store.
300 * G-Expressions:: Manipulating build expressions.
301 * Invoking guix repl:: Programming Guix in Guile.
302 * Using Guix Interactively:: Fine-grain interaction at the REPL.
306 * package Reference:: The package data type.
307 * origin Reference:: The origin data type.
311 * Invoking guix build:: Building packages from the command line.
312 * Invoking guix edit:: Editing package definitions.
313 * Invoking guix download:: Downloading a file and printing its hash.
314 * Invoking guix hash:: Computing the cryptographic hash of a file.
315 * Invoking guix import:: Importing package definitions.
316 * Invoking guix refresh:: Updating package definitions.
317 * Invoking guix style:: Styling package definitions.
318 * Invoking guix lint:: Finding errors in package definitions.
319 * Invoking guix size:: Profiling disk usage.
320 * Invoking guix graph:: Visualizing the graph of packages.
321 * Invoking guix publish:: Sharing substitutes.
322 * Invoking guix challenge:: Challenging substitute servers.
323 * Invoking guix copy:: Copying to and from a remote store.
324 * Invoking guix container:: Process isolation.
325 * Invoking guix weather:: Assessing substitute availability.
326 * Invoking guix processes:: Listing client processes.
328 Invoking @command{guix build}
330 * Common Build Options:: Build options for most commands.
331 * Package Transformation Options:: Creating variants of packages.
332 * Additional Build Options:: Options specific to 'guix build'.
333 * Debugging Build Failures:: Real life packaging experience.
335 Foreign Architectures
336 * Cross-Compilation:: Cross-compiling for another architecture.
337 * Native Builds:: Targeting another architecture through native builds.
341 * Using the Configuration System:: Customizing your GNU system.
342 * operating-system Reference:: Detail of operating-system declarations.
343 * File Systems:: Configuring file system mounts.
344 * Mapped Devices:: Block device extra processing.
345 * Swap Space:: Backing RAM with disk space.
346 * User Accounts:: Specifying user accounts.
347 * Keyboard Layout:: How the system interprets key strokes.
348 * Locales:: Language and cultural convention settings.
349 * Services:: Specifying system services.
350 * Setuid Programs:: Programs running with elevated privileges.
351 * X.509 Certificates:: Authenticating HTTPS servers.
352 * Name Service Switch:: Configuring libc's name service switch.
353 * Initial RAM Disk:: Linux-Libre bootstrapping.
354 * Bootloader Configuration:: Configuring the boot loader.
355 * Invoking guix system:: Instantiating a system configuration.
356 * Invoking guix deploy:: Deploying a system configuration to a remote host.
357 * Running Guix in a VM:: How to run Guix System in a virtual machine.
358 * Defining Services:: Adding new service definitions.
360 Home Environment Configuration
362 * Invoking guix home:: Instantiating a home environment configuration.
366 * Base Services:: Essential system services.
367 * Scheduled Job Execution:: The mcron service.
368 * Log Rotation:: The rottlog service.
369 * Networking Setup:: Setting up network interfaces.
370 * Networking Services:: Firewall, SSH daemon, etc.
371 * Unattended Upgrades:: Automated system upgrades.
372 * X Window:: Graphical display.
373 * Printing Services:: Local and remote printer support.
374 * Desktop Services:: D-Bus and desktop services.
375 * Sound Services:: ALSA and Pulseaudio services.
376 * Database Services:: SQL databases, key-value stores, etc.
377 * Mail Services:: IMAP, POP3, SMTP, and all that.
378 * Messaging Services:: Messaging services.
379 * Telephony Services:: Telephony services.
380 * Monitoring Services:: Monitoring services.
381 * Kerberos Services:: Kerberos services.
382 * LDAP Services:: LDAP services.
383 * Web Services:: Web servers.
384 * Certificate Services:: TLS certificates via Let's Encrypt.
385 * DNS Services:: DNS daemons.
386 * VPN Services:: VPN daemons.
387 * Network File System:: NFS related services.
388 * Continuous Integration:: Cuirass and Laminar services.
389 * Power Management Services:: Extending battery life.
390 * Audio Services:: The MPD.
391 * Virtualization Services:: Virtualization services.
392 * Version Control Services:: Providing remote access to Git repositories.
393 * Game Services:: Game servers.
394 * PAM Mount Service:: Service to mount volumes when logging in.
395 * Guix Services:: Services relating specifically to Guix.
396 * Linux Services:: Services tied to the Linux kernel.
397 * Hurd Services:: Services specific for a Hurd System.
398 * Miscellaneous Services:: Other services.
402 * Service Composition:: The model for composing services.
403 * Service Types and Services:: Types and services.
404 * Service Reference:: API reference.
405 * Shepherd Services:: A particular type of service.
406 * Complex Configurations:: Defining bindings for complex configurations.
408 Installing Debugging Files
410 * Separate Debug Info:: Installing 'debug' outputs.
411 * Rebuilding Debug Info:: Building missing debug info.
415 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
416 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
421 @c *********************************************************************
423 @chapter Introduction
426 GNU Guix@footnote{``Guix'' is pronounced like ``geeks'', or ``ɡiːks''
427 using the international phonetic alphabet (IPA).} is a package
428 management tool for and distribution of the GNU system.
429 Guix makes it easy for unprivileged
430 users to install, upgrade, or remove software packages, to roll back to a
431 previous package set, to build packages from source, and generally
432 assists with the creation and maintenance of software environments.
435 @cindex GuixSD, now Guix System
436 @cindex Guix System Distribution, now Guix System
437 You can install GNU@tie{}Guix on top of an existing GNU/Linux system where it
438 complements the available tools without interference (@pxref{Installation}),
439 or you can use it as a standalone operating system distribution,
440 @dfn{Guix@tie{}System}@footnote{We used to refer to Guix System as ``Guix
441 System Distribution'' or ``GuixSD''. We now consider it makes more sense to
442 group everything under the ``Guix'' banner since, after all, Guix System is
443 readily available through the @command{guix system} command, even if you're
444 using a different distro underneath!}. @xref{GNU Distribution}.
447 * Managing Software the Guix Way:: What's special.
448 * GNU Distribution:: The packages and tools.
451 @node Managing Software the Guix Way
452 @section Managing Software the Guix Way
454 @cindex user interfaces
455 Guix provides a command-line package management interface
456 (@pxref{Package Management}), tools to help with software development
457 (@pxref{Development}), command-line utilities for more advanced usage
458 (@pxref{Utilities}), as well as Scheme programming interfaces
459 (@pxref{Programming Interface}).
461 Its @dfn{build daemon} is responsible for building packages on behalf of
462 users (@pxref{Setting Up the Daemon}) and for downloading pre-built
463 binaries from authorized sources (@pxref{Substitutes}).
465 @cindex extensibility of the distribution
466 @cindex customization, of packages
467 Guix includes package definitions for many GNU and non-GNU packages, all
468 of which @uref{https://www.gnu.org/philosophy/free-sw.html, respect the
469 user's computing freedom}. It is @emph{extensible}: users can write
470 their own package definitions (@pxref{Defining Packages}) and make them
471 available as independent package modules (@pxref{Package Modules}). It
472 is also @emph{customizable}: users can @emph{derive} specialized package
473 definitions from existing ones, including from the command line
474 (@pxref{Package Transformation Options}).
476 @cindex functional package management
478 Under the hood, Guix implements the @dfn{functional package management}
479 discipline pioneered by Nix (@pxref{Acknowledgments}).
480 In Guix, the package build and installation process is seen
481 as a @emph{function}, in the mathematical sense. That function takes inputs,
482 such as build scripts, a compiler, and libraries, and
483 returns an installed package. As a pure function, its result depends
484 solely on its inputs---for instance, it cannot refer to software or
485 scripts that were not explicitly passed as inputs. A build function
486 always produces the same result when passed a given set of inputs. It
487 cannot alter the environment of the running system in
488 any way; for instance, it cannot create, modify, or delete files outside
489 of its build and installation directories. This is achieved by running
490 build processes in isolated environments (or @dfn{containers}), where only their
491 explicit inputs are visible.
494 The result of package build functions is @dfn{cached} in the file
495 system, in a special directory called @dfn{the store} (@pxref{The
496 Store}). Each package is installed in a directory of its own in the
497 store---by default under @file{/gnu/store}. The directory name contains
498 a hash of all the inputs used to build that package; thus, changing an
499 input yields a different directory name.
501 This approach is the foundation for the salient features of Guix: support
502 for transactional package upgrade and rollback, per-user installation, and
503 garbage collection of packages (@pxref{Features}).
506 @node GNU Distribution
507 @section GNU Distribution
510 Guix comes with a distribution of the GNU system consisting entirely of
511 free software@footnote{The term ``free'' here refers to the
512 @url{https://www.gnu.org/philosophy/free-sw.html,freedom provided to
513 users of that software}.}. The
514 distribution can be installed on its own (@pxref{System Installation}),
515 but it is also possible to install Guix as a package manager on top of
516 an installed GNU/Linux system (@pxref{Installation}). When we need to
517 distinguish between the two, we refer to the standalone distribution as
520 The distribution provides core GNU packages such as GNU libc, GCC, and
521 Binutils, as well as many GNU and non-GNU applications. The complete
522 list of available packages can be browsed
523 @url{https://www.gnu.org/software/guix/packages,on-line} or by
524 running @command{guix package} (@pxref{Invoking guix package}):
527 guix package --list-available
530 Our goal is to provide a practical 100% free software distribution of
531 Linux-based and other variants of GNU, with a focus on the promotion and
532 tight integration of GNU components, and an emphasis on programs and
533 tools that help users exert that freedom.
535 Packages are currently available on the following platforms:
540 Intel/AMD @code{x86_64} architecture, Linux-Libre kernel.
543 Intel 32-bit architecture (IA32), Linux-Libre kernel.
546 ARMv7-A architecture with hard float, Thumb-2 and NEON,
547 using the EABI hard-float application binary interface (ABI),
548 and Linux-Libre kernel.
551 little-endian 64-bit ARMv8-A processors, Linux-Libre kernel.
554 @uref{https://hurd.gnu.org, GNU/Hurd} on the Intel 32-bit architecture
557 This configuration is experimental and under development. The easiest
558 way for you to give it a try is by setting up an instance of
559 @code{hurd-vm-service-type} on your GNU/Linux machine
560 (@pxref{transparent-emulation-qemu, @code{hurd-vm-service-type}}).
561 @xref{Contributing}, on how to help!
563 @item mips64el-linux (unsupported)
564 little-endian 64-bit MIPS processors, specifically the Loongson series,
565 n32 ABI, and Linux-Libre kernel. This configuration is no longer fully
566 supported; in particular, there is no ongoing work to ensure that this
567 architecture still works. Should someone decide they wish to revive this
568 architecture then the code is still available.
570 @item powerpc-linux (unsupported)
571 big-endian 32-bit PowerPC processors, specifically the PowerPC G4 with
572 AltiVec support, and Linux-Libre kernel. This configuration is not
573 fully supported and there is no ongoing work to ensure this architecture
576 @item powerpc64le-linux
577 little-endian 64-bit Power ISA processors, Linux-Libre kernel. This
578 includes POWER9 systems such as the
579 @uref{https://www.fsf.org/news/talos-ii-mainboard-and-talos-ii-lite-mainboard-now-fsf-certified-to-respect-your-freedom,
580 RYF Talos II mainboard}. This platform is available as a "technology
581 preview": although it is supported, substitutes are not yet available
582 from the build farm (@pxref{Substitutes}), and some packages may fail to
583 build (@pxref{Tracking Bugs and Patches}). That said, the Guix
584 community is actively working on improving this support, and now is a
585 great time to try it and get involved!
588 little-endian 64-bit RISC-V processors, specifically RV64GC, and
589 Linux-Libre kernel. This playform is available as a "technology preview":
590 although it is supported, substitutes are not yet available from the
591 build farm (@pxref{Substitutes}), and some packages may fail to build
592 (@pxref{Tracking Bugs and Patches}). That said, the Guix community is
593 actively working on improving this support, and now is a great time to
594 try it and get involved!
598 With Guix@tie{}System, you @emph{declare} all aspects of the operating system
599 configuration and Guix takes care of instantiating the configuration in a
600 transactional, reproducible, and stateless fashion (@pxref{System
601 Configuration}). Guix System uses the Linux-libre kernel, the Shepherd
602 initialization system (@pxref{Introduction,,, shepherd, The GNU Shepherd
603 Manual}), the well-known GNU utilities and tool chain, as well as the
604 graphical environment or system services of your choice.
606 Guix System is available on all the above platforms except
607 @code{mips64el-linux}, @code{powerpc-linux}, @code{powerpc64le-linux} and
608 @code{riscv64-linux}.
611 For information on porting to other architectures or kernels,
614 Building this distribution is a cooperative effort, and you are invited
615 to join! @xref{Contributing}, for information about how you can help.
618 @c *********************************************************************
620 @chapter Installation
622 @cindex installing Guix
625 We recommend the use of this
626 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
627 shell installer script} to install Guix on top of a running GNU/Linux system,
628 thereafter called a @dfn{foreign distro}.@footnote{This section is concerned
629 with the installation of the package manager, which can be done on top of a
630 running GNU/Linux system. If, instead, you want to install the complete GNU
631 operating system, @pxref{System Installation}.} The script automates the
632 download, installation, and initial configuration of Guix. It should be run
636 @cindex foreign distro
637 @cindex directories related to foreign distro
638 When installed on a foreign distro, GNU@tie{}Guix complements the available
639 tools without interference. Its data lives exclusively in two directories,
640 usually @file{/gnu/store} and @file{/var/guix}; other files on your system,
641 such as @file{/etc}, are left untouched.
643 Once installed, Guix can be updated by running @command{guix pull}
644 (@pxref{Invoking guix pull}).
646 If you prefer to perform the installation steps manually or want to tweak
647 them, you may find the following subsections useful. They describe the
648 software requirements of Guix, as well as how to install it manually and get
652 * Binary Installation:: Getting Guix running in no time!
653 * Requirements:: Software needed to build and run Guix.
654 * Running the Test Suite:: Testing Guix.
655 * Setting Up the Daemon:: Preparing the build daemon's environment.
656 * Invoking guix-daemon:: Running the build daemon.
657 * Application Setup:: Application-specific setup.
658 * Upgrading Guix:: Upgrading Guix and its build daemon.
661 @node Binary Installation
662 @section Binary Installation
664 @cindex installing Guix from binaries
665 @cindex installer script
666 This section describes how to install Guix on an arbitrary system from a
667 self-contained tarball providing binaries for Guix and for all its
668 dependencies. This is often quicker than installing from source, which
669 is described in the next sections. The only requirement is to have
672 @c Note duplicated from the ``Installation'' node.
674 We recommend the use of this
675 @uref{https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh,
676 shell installer script}. The script automates the download, installation, and
677 initial configuration steps described below. It should be run as the root
678 user. As root, you can thus run this:
682 wget https://git.savannah.gnu.org/cgit/guix.git/plain/etc/guix-install.sh
683 chmod +x guix-install.sh
687 If you're running Debian or a derivative such as Ubuntu, you can instead
688 install the package (it might be a version older than @value{VERSION}
689 but you can update it afterwards by running @samp{guix pull}):
692 sudo apt install guix
695 Likewise on openSUSE:
698 sudo zypper install guix
701 When you're done, @pxref{Application Setup} for extra configuration you
702 might need, and @ref{Getting Started} for your first steps!
705 Installing goes along these lines:
709 @cindex downloading Guix binary
710 Download the binary tarball from
711 @indicateurl{@value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz},
712 where @code{x86_64-linux} can be replaced with @code{i686-linux} for an
713 @code{i686} (32-bits) machine already running the kernel Linux, and so on
714 (@pxref{GNU Distribution}).
716 @c The following is somewhat duplicated in ``System Installation''.
717 Make sure to download the associated @file{.sig} file and to verify the
718 authenticity of the tarball against it, along these lines:
721 $ wget @value{BASE-URL}/guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
722 $ gpg --verify guix-binary-@value{VERSION}.x86_64-linux.tar.xz.sig
725 If that command fails because you do not have the required public key,
726 then run this command to import it:
729 $ wget '@value{OPENPGP-SIGNING-KEY-URL}' \
730 -qO - | gpg --import -
734 and rerun the @code{gpg --verify} command.
736 Take note that a warning like ``This key is not certified with a trusted
737 signature!'' is normal.
739 @c end authentication part
742 Now, you need to become the @code{root} user. Depending on your distribution,
743 you may have to run @code{su -} or @code{sudo -i}. As @code{root}, run:
747 # tar --warning=no-timestamp -xf \
748 /path/to/guix-binary-@value{VERSION}.x86_64-linux.tar.xz
749 # mv var/guix /var/ && mv gnu /
752 This creates @file{/gnu/store} (@pxref{The Store}) and @file{/var/guix}.
753 The latter contains a ready-to-use profile for @code{root} (see next
756 Do @emph{not} unpack the tarball on a working Guix system since that
757 would overwrite its own essential files.
759 The @option{--warning=no-timestamp} option makes sure GNU@tie{}tar does
760 not emit warnings about ``implausibly old time stamps'' (such
761 warnings were triggered by GNU@tie{}tar 1.26 and older; recent
763 They stem from the fact that all the
764 files in the archive have their modification time set to 1 (which
765 means January 1st, 1970). This is done on purpose to make sure the
766 archive content is independent of its creation time, thus making it
770 Make the profile available under @file{~root/.config/guix/current}, which is
771 where @command{guix pull} will install updates (@pxref{Invoking guix pull}):
774 # mkdir -p ~root/.config/guix
775 # ln -sf /var/guix/profiles/per-user/root/current-guix \
776 ~root/.config/guix/current
779 Source @file{etc/profile} to augment @env{PATH} and other relevant
780 environment variables:
783 # GUIX_PROFILE="`echo ~root`/.config/guix/current" ; \
784 source $GUIX_PROFILE/etc/profile
788 Create the group and user accounts for build users as explained below
789 (@pxref{Build Environment Setup}).
792 Run the daemon, and set it to automatically start on boot.
794 If your host distro uses the systemd init system, this can be achieved
797 @c Versions of systemd that supported symlinked service files are not
798 @c yet widely deployed, so we should suggest that users copy the service
801 @c See this thread for more information:
802 @c https://lists.gnu.org/archive/html/guix-devel/2017-01/msg01199.html
805 # cp ~root/.config/guix/current/lib/systemd/system/gnu-store.mount \
806 ~root/.config/guix/current/lib/systemd/system/guix-daemon.service \
808 # systemctl enable --now gnu-store.mount guix-daemon
811 You may also want to arrange for @command{guix gc} to run periodically:
814 # cp ~root/.config/guix/current/lib/systemd/system/guix-gc.service \
815 ~root/.config/guix/current/lib/systemd/system/guix-gc.timer \
817 # systemctl enable --now guix-gc.timer
820 You may want to edit @file{guix-gc.service} to adjust the command line
821 options to fit your needs (@pxref{Invoking guix gc}).
823 If your host distro uses the Upstart init system:
826 # initctl reload-configuration
827 # cp ~root/.config/guix/current/lib/upstart/system/guix-daemon.conf \
832 Otherwise, you can still start the daemon manually with:
835 # ~root/.config/guix/current/bin/guix-daemon \
836 --build-users-group=guixbuild
840 Make the @command{guix} command available to other users on the machine,
844 # mkdir -p /usr/local/bin
846 # ln -s /var/guix/profiles/per-user/root/current-guix/bin/guix
849 It is also a good idea to make the Info version of this manual available
853 # mkdir -p /usr/local/share/info
854 # cd /usr/local/share/info
855 # for i in /var/guix/profiles/per-user/root/current-guix/share/info/* ;
859 That way, assuming @file{/usr/local/share/info} is in the search path,
860 running @command{info guix} will open this manual (@pxref{Other Info
861 Directories,,, texinfo, GNU Texinfo}, for more details on changing the
865 @cindex substitutes, authorization thereof
866 To use substitutes from @code{@value{SUBSTITUTE-SERVER-1}},
867 @code{@value{SUBSTITUTE-SERVER-2}} or a mirror (@pxref{Substitutes}),
871 # guix archive --authorize < \
872 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
873 # guix archive --authorize < \
874 ~root/.config/guix/current/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
878 If you do not enable substitutes, Guix will end up building
879 @emph{everything} from source on your machine, making each installation
880 and upgrade very expensive. @xref{On Trusting Binaries}, for a
881 discussion of reasons why one might want do disable substitutes.
885 Each user may need to perform a few additional steps to make their Guix
886 environment ready for use, @pxref{Application Setup}.
889 Voilà, the installation is complete!
891 You can confirm that Guix is working by installing a sample package into
898 The binary installation tarball can be (re)produced and verified simply
899 by running the following command in the Guix source tree:
902 make guix-binary.@var{system}.tar.xz
906 ...@: which, in turn, runs:
909 guix pack -s @var{system} --localstatedir \
910 --profile-name=current-guix guix
913 @xref{Invoking guix pack}, for more info on this handy tool.
916 @section Requirements
918 This section lists requirements when building Guix from source. The
919 build procedure for Guix is the same as for other GNU software, and is
920 not covered here. Please see the files @file{README} and @file{INSTALL}
921 in the Guix source tree for additional details.
923 @cindex official website
924 GNU Guix is available for download from its website at
925 @url{https://www.gnu.org/software/guix/}.
927 GNU Guix depends on the following packages:
930 @item @url{https://gnu.org/software/guile/, GNU Guile}, version 3.0.x,
931 version 3.0.3 or later;
932 @item @url{https://notabug.org/cwebber/guile-gcrypt, Guile-Gcrypt}, version
935 @uref{https://gnutls.org/, GnuTLS}, specifically its Guile bindings
936 (@pxref{Guile Preparations, how to install the GnuTLS bindings for
937 Guile,, gnutls-guile, GnuTLS-Guile});
939 @uref{https://notabug.org/guile-sqlite3/guile-sqlite3, Guile-SQLite3}, version 0.1.0
941 @item @uref{https://notabug.org/guile-zlib/guile-zlib, Guile-zlib},
942 version 0.1.0 or later;
943 @item @uref{https://notabug.org/guile-lzlib/guile-lzlib, Guile-lzlib};
944 @item @uref{https://www.nongnu.org/guile-avahi/, Guile-Avahi};
946 @uref{https://gitlab.com/guile-git/guile-git, Guile-Git}, version 0.5.0
948 @item @uref{https://savannah.nongnu.org/projects/guile-json/, Guile-JSON}
950 @item @url{https://www.gnu.org/software/make/, GNU Make}.
953 The following dependencies are optional:
957 @c Note: We need at least 0.13.0 for #:nodelay.
958 Support for build offloading (@pxref{Daemon Offload Setup}) and
959 @command{guix copy} (@pxref{Invoking guix copy}) depends on
960 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH},
961 version 0.13.0 or later.
964 @uref{https://notabug.org/guile-zstd/guile-zstd, Guile-zstd}, for zstd
965 compression and decompression in @command{guix publish} and for
966 substitutes (@pxref{Invoking guix publish}).
969 @uref{https://ngyro.com/software/guile-semver.html, Guile-Semver} for
970 the @code{crate} importer (@pxref{Invoking guix import}).
973 @uref{https://www.nongnu.org/guile-lib/doc/ref/htmlprag/, Guile-Lib} for
974 the @code{go} importer (@pxref{Invoking guix import}) and for some of
975 the ``updaters'' (@pxref{Invoking guix refresh}).
978 When @url{http://www.bzip.org, libbz2} is available,
979 @command{guix-daemon} can use it to compress build logs.
982 Unless @option{--disable-daemon} was passed to @command{configure}, the
983 following packages are also needed:
986 @item @url{https://gnupg.org/, GNU libgcrypt};
987 @item @url{https://sqlite.org, SQLite 3};
988 @item @url{https://gcc.gnu.org, GCC's g++}, with support for the
992 @cindex state directory
993 When configuring Guix on a system that already has a Guix installation,
994 be sure to specify the same state directory as the existing installation
995 using the @option{--localstatedir} option of the @command{configure}
996 script (@pxref{Directory Variables, @code{localstatedir},, standards,
997 GNU Coding Standards}). Usually, this @var{localstatedir} option is
998 set to the value @file{/var}. The @command{configure} script protects
999 against unintended misconfiguration of @var{localstatedir} so you do not
1000 inadvertently corrupt your store (@pxref{The Store}).
1002 @node Running the Test Suite
1003 @section Running the Test Suite
1006 After a successful @command{configure} and @code{make} run, it is a good
1007 idea to run the test suite. It can help catch issues with the setup or
1008 environment, or bugs in Guix itself---and really, reporting test
1009 failures is a good way to help improve the software. To run the test
1016 Test cases can run in parallel: you can use the @code{-j} option of
1017 GNU@tie{}make to speed things up. The first run may take a few minutes
1018 on a recent machine; subsequent runs will be faster because the store
1019 that is created for test purposes will already have various things in
1022 It is also possible to run a subset of the tests by defining the
1023 @code{TESTS} makefile variable as in this example:
1026 make check TESTS="tests/store.scm tests/cpio.scm"
1029 By default, tests results are displayed at a file level. In order to
1030 see the details of every individual test cases, it is possible to define
1031 the @code{SCM_LOG_DRIVER_FLAGS} makefile variable as in this example:
1034 make check TESTS="tests/base64.scm" SCM_LOG_DRIVER_FLAGS="--brief=no"
1037 The underlying SRFI 64 custom Automake test driver used for the 'check'
1038 test suite (located at @file{build-aux/test-driver.scm}) also allows
1039 selecting which test cases to run at a finer level, via its
1040 @option{--select} and @option{--exclude} options. Here's an example, to
1041 run all the test cases from the @file{tests/packages.scm} test file
1042 whose names start with ``transaction-upgrade-entry'':
1045 export SCM_LOG_DRIVER_FLAGS="--select=^transaction-upgrade-entry"
1046 make check TESTS="tests/packages.scm"
1049 Those wishing to inspect the results of failed tests directly from the
1050 command line can add the @option{--errors-only=yes} option to the
1051 @code{SCM_LOG_DRIVER_FLAGS} makefile variable and set the @code{VERBOSE}
1052 Automake makefile variable, as in:
1055 make check SCM_LOG_DRIVER_FLAGS="--brief=no --errors-only=yes" VERBOSE=1
1058 The @option{--show-duration=yes} option can be used to print the
1059 duration of the individual test cases, when used in combination with
1060 @option{--brief=no}:
1063 make check SCM_LOG_DRIVER_FLAGS="--brief=no --show-duration=yes"
1066 @xref{Parallel Test Harness,,,automake,GNU Automake} for more
1067 information about the Automake Parallel Test Harness.
1069 Upon failure, please email @email{bug-guix@@gnu.org} and attach the
1070 @file{test-suite.log} file. Please specify the Guix version being used
1071 as well as version numbers of the dependencies (@pxref{Requirements}) in
1074 Guix also comes with a whole-system test suite that tests complete
1075 Guix System instances. It can only run on systems where
1076 Guix is already installed, using:
1083 or, again, by defining @code{TESTS} to select a subset of tests to run:
1086 make check-system TESTS="basic mcron"
1089 These system tests are defined in the @code{(gnu tests @dots{})}
1090 modules. They work by running the operating systems under test with
1091 lightweight instrumentation in a virtual machine (VM). They can be
1092 computationally intensive or rather cheap, depending on whether
1093 substitutes are available for their dependencies (@pxref{Substitutes}).
1094 Some of them require a lot of storage space to hold VM images.
1096 Again in case of test failures, please send @email{bug-guix@@gnu.org}
1099 @node Setting Up the Daemon
1100 @section Setting Up the Daemon
1103 Operations such as building a package or running the garbage collector
1104 are all performed by a specialized process, the @dfn{build daemon}, on
1105 behalf of clients. Only the daemon may access the store and its
1106 associated database. Thus, any operation that manipulates the store
1107 goes through the daemon. For instance, command-line tools such as
1108 @command{guix package} and @command{guix build} communicate with the
1109 daemon (@i{via} remote procedure calls) to instruct it what to do.
1111 The following sections explain how to prepare the build daemon's
1112 environment. See also @ref{Substitutes}, for information on how to allow
1113 the daemon to download pre-built binaries.
1116 * Build Environment Setup:: Preparing the isolated build environment.
1117 * Daemon Offload Setup:: Offloading builds to remote machines.
1118 * SELinux Support:: Using an SELinux policy for the daemon.
1121 @node Build Environment Setup
1122 @subsection Build Environment Setup
1124 @cindex build environment
1125 In a standard multi-user setup, Guix and its daemon---the
1126 @command{guix-daemon} program---are installed by the system
1127 administrator; @file{/gnu/store} is owned by @code{root} and
1128 @command{guix-daemon} runs as @code{root}. Unprivileged users may use
1129 Guix tools to build packages or otherwise access the store, and the
1130 daemon will do it on their behalf, ensuring that the store is kept in a
1131 consistent state, and allowing built packages to be shared among users.
1134 When @command{guix-daemon} runs as @code{root}, you may not want package
1135 build processes themselves to run as @code{root} too, for obvious
1136 security reasons. To avoid that, a special pool of @dfn{build users}
1137 should be created for use by build processes started by the daemon.
1138 These build users need not have a shell and a home directory: they will
1139 just be used when the daemon drops @code{root} privileges in build
1140 processes. Having several such users allows the daemon to launch
1141 distinct build processes under separate UIDs, which guarantees that they
1142 do not interfere with each other---an essential feature since builds are
1143 regarded as pure functions (@pxref{Introduction}).
1145 On a GNU/Linux system, a build user pool may be created like this (using
1146 Bash syntax and the @code{shadow} commands):
1148 @c See https://lists.gnu.org/archive/html/bug-guix/2013-01/msg00239.html
1149 @c for why `-G' is needed.
1151 # groupadd --system guixbuild
1152 # for i in $(seq -w 1 10);
1154 useradd -g guixbuild -G guixbuild \
1155 -d /var/empty -s $(which nologin) \
1156 -c "Guix build user $i" --system \
1162 The number of build users determines how many build jobs may run in
1163 parallel, as specified by the @option{--max-jobs} option
1164 (@pxref{Invoking guix-daemon, @option{--max-jobs}}). To use
1165 @command{guix system vm} and related commands, you may need to add the
1166 build users to the @code{kvm} group so they can access @file{/dev/kvm},
1167 using @code{-G guixbuild,kvm} instead of @code{-G guixbuild}
1168 (@pxref{Invoking guix system}).
1170 The @code{guix-daemon} program may then be run as @code{root} with the
1171 following command@footnote{If your machine uses the systemd init system,
1172 copying the @file{@var{prefix}/lib/systemd/system/guix-daemon.service}
1173 file to @file{/etc/systemd/system} will ensure that
1174 @command{guix-daemon} is automatically started. Similarly, if your
1175 machine uses the Upstart init system, copy the
1176 @file{@var{prefix}/lib/upstart/system/guix-daemon.conf}
1177 file to @file{/etc/init}.}:
1180 # guix-daemon --build-users-group=guixbuild
1185 This way, the daemon starts build processes in a chroot, under one of
1186 the @code{guixbuilder} users. On GNU/Linux, by default, the chroot
1187 environment contains nothing but:
1189 @c Keep this list in sync with libstore/build.cc! -----------------------
1192 a minimal @code{/dev} directory, created mostly independently from the
1193 host @code{/dev}@footnote{``Mostly'', because while the set of files
1194 that appear in the chroot's @code{/dev} is fixed, most of these files
1195 can only be created if the host has them.};
1198 the @code{/proc} directory; it only shows the processes of the container
1199 since a separate PID name space is used;
1202 @file{/etc/passwd} with an entry for the current user and an entry for
1206 @file{/etc/group} with an entry for the user's group;
1209 @file{/etc/hosts} with an entry that maps @code{localhost} to
1213 a writable @file{/tmp} directory.
1216 The chroot does not contain a @file{/home} directory, and the @env{HOME}
1217 environment variable is set to the non-existent
1218 @file{/homeless-shelter}. This helps to highlight inappropriate uses of
1219 @env{HOME} in the build scripts of packages.
1221 You can influence the directory where the daemon stores build trees
1222 @i{via} the @env{TMPDIR} environment variable. However, the build tree
1223 within the chroot is always called @file{/tmp/guix-build-@var{name}.drv-0},
1224 where @var{name} is the derivation name---e.g., @code{coreutils-8.24}.
1225 This way, the value of @env{TMPDIR} does not leak inside build
1226 environments, which avoids discrepancies in cases where build processes
1227 capture the name of their build tree.
1231 The daemon also honors the @env{http_proxy} and @env{https_proxy}
1232 environment variables for HTTP and HTTPS downloads it performs, be it
1233 for fixed-output derivations (@pxref{Derivations}) or for substitutes
1234 (@pxref{Substitutes}).
1236 If you are installing Guix as an unprivileged user, it is still possible
1237 to run @command{guix-daemon} provided you pass @option{--disable-chroot}.
1238 However, build processes will not be isolated from one another, and not
1239 from the rest of the system. Thus, build processes may interfere with
1240 each other, and may access programs, libraries, and other files
1241 available on the system---making it much harder to view them as
1242 @emph{pure} functions.
1245 @node Daemon Offload Setup
1246 @subsection Using the Offload Facility
1250 When desired, the build daemon can @dfn{offload} derivation builds to
1251 other machines running Guix, using the @code{offload} @dfn{build
1252 hook}@footnote{This feature is available only when
1253 @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is
1254 present.}. When that feature is enabled, a list of user-specified build
1255 machines is read from @file{/etc/guix/machines.scm}; every time a build
1256 is requested, for instance via @code{guix build}, the daemon attempts to
1257 offload it to one of the machines that satisfy the constraints of the
1258 derivation, in particular its system types---e.g., @code{x86_64-linux}.
1259 A single machine can have multiple system types, either because its
1260 architecture natively supports it, via emulation
1261 (@pxref{transparent-emulation-qemu, Transparent Emulation with QEMU}),
1262 or both. Missing prerequisites for the build are
1263 copied over SSH to the target machine, which then proceeds with the
1264 build; upon success the output(s) of the build are copied back to the
1265 initial machine. The offload facility comes with a basic scheduler that
1266 attempts to select the best machine. The best machine is chosen among
1267 the available machines based on criteria such as:
1271 The availability of a build slot. A build machine can have as many
1272 build slots (connections) as the value of the @code{parallel-builds}
1273 field of its @code{build-machine} object.
1276 Its relative speed, as defined via the @code{speed} field of its
1277 @code{build-machine} object.
1280 Its load. The normalized machine load must be lower than a threshold
1281 value, configurable via the @code{overload-threshold} field of its
1282 @code{build-machine} object.
1285 Disk space availability. More than a 100 MiB must be available.
1288 The @file{/etc/guix/machines.scm} file typically looks like this:
1291 (list (build-machine
1292 (name "eightysix.example.org")
1293 (systems (list "x86_64-linux" "i686-linux"))
1294 (host-key "ssh-ed25519 AAAAC3Nza@dots{}")
1296 (speed 2.)) ;incredibly fast!
1299 (name "armeight.example.org")
1300 (systems (list "aarch64-linux"))
1301 (host-key "ssh-rsa AAAAB3Nza@dots{}")
1304 ;; Remember 'guix offload' is spawned by
1305 ;; 'guix-daemon' as root.
1306 (private-key "/root/.ssh/identity-for-guix")))
1310 In the example above we specify a list of two build machines, one for
1311 the @code{x86_64} and @code{i686} architectures and one for the
1312 @code{aarch64} architecture.
1314 In fact, this file is---not surprisingly!---a Scheme file that is
1315 evaluated when the @code{offload} hook is started. Its return value
1316 must be a list of @code{build-machine} objects. While this example
1317 shows a fixed list of build machines, one could imagine, say, using
1318 DNS-SD to return a list of potential build machines discovered in the
1319 local network (@pxref{Introduction, Guile-Avahi,, guile-avahi, Using
1320 Avahi in Guile Scheme Programs}). The @code{build-machine} data type is
1323 @deftp {Data Type} build-machine
1324 This data type represents build machines to which the daemon may offload
1325 builds. The important fields are:
1330 The host name of the remote machine.
1333 The system types the remote machine supports---e.g., @code{(list
1334 "x86_64-linux" "i686-linux")}.
1337 The user account to use when connecting to the remote machine over SSH.
1338 Note that the SSH key pair must @emph{not} be passphrase-protected, to
1339 allow non-interactive logins.
1342 This must be the machine's SSH @dfn{public host key} in OpenSSH format.
1343 This is used to authenticate the machine when we connect to it. It is a
1344 long string that looks like this:
1347 ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org
1350 If the machine is running the OpenSSH daemon, @command{sshd}, the host
1351 key can be found in a file such as
1352 @file{/etc/ssh/ssh_host_ed25519_key.pub}.
1354 If the machine is running the SSH daemon of GNU@tie{}lsh,
1355 @command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a
1356 similar file. It can be converted to the OpenSSH format using
1357 @command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}):
1360 $ lsh-export-key --openssh < /etc/lsh/host-key.pub
1361 ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{}
1366 A number of optional fields may be specified:
1370 @item @code{port} (default: @code{22})
1371 Port number of SSH server on the machine.
1373 @item @code{private-key} (default: @file{~root/.ssh/id_rsa})
1374 The SSH private key file to use when connecting to the machine, in
1375 OpenSSH format. This key must not be protected with a passphrase.
1377 Note that the default value is the private key @emph{of the root
1378 account}. Make sure it exists if you use the default.
1380 @item @code{compression} (default: @code{"zlib@@openssh.com,zlib"})
1381 @itemx @code{compression-level} (default: @code{3})
1382 The SSH-level compression methods and compression level requested.
1384 Note that offloading relies on SSH compression to reduce bandwidth usage
1385 when transferring files to and from build machines.
1387 @item @code{daemon-socket} (default: @code{"/var/guix/daemon-socket/socket"})
1388 File name of the Unix-domain socket @command{guix-daemon} is listening
1391 @item @code{overload-threshold} (default: @code{0.6})
1392 The load threshold above which a potential offload machine is
1393 disregarded by the offload scheduler. The value roughly translates to
1394 the total processor usage of the build machine, ranging from 0.0 (0%) to
1395 1.0 (100%). It can also be disabled by setting
1396 @code{overload-threshold} to @code{#f}.
1398 @item @code{parallel-builds} (default: @code{1})
1399 The number of builds that may run in parallel on the machine.
1401 @item @code{speed} (default: @code{1.0})
1402 A ``relative speed factor''. The offload scheduler will tend to prefer
1403 machines with a higher speed factor.
1405 @item @code{features} (default: @code{'()})
1406 A list of strings denoting specific features supported by the machine.
1407 An example is @code{"kvm"} for machines that have the KVM Linux modules
1408 and corresponding hardware support. Derivations can request features by
1409 name, and they will be scheduled on matching build machines.
1414 The @command{guix} command must be in the search path on the build
1415 machines. You can check whether this is the case by running:
1418 ssh build-machine guix repl --version
1421 There is one last thing to do once @file{machines.scm} is in place. As
1422 explained above, when offloading, files are transferred back and forth
1423 between the machine stores. For this to work, you first need to
1424 generate a key pair on each machine to allow the daemon to export signed
1425 archives of files from the store (@pxref{Invoking guix archive}):
1428 # guix archive --generate-key
1432 Each build machine must authorize the key of the master machine so that
1433 it accepts store items it receives from the master:
1436 # guix archive --authorize < master-public-key.txt
1440 Likewise, the master machine must authorize the key of each build machine.
1442 All the fuss with keys is here to express pairwise mutual trust
1443 relations between the master and the build machines. Concretely, when
1444 the master receives files from a build machine (and @i{vice versa}), its
1445 build daemon can make sure they are genuine, have not been tampered
1446 with, and that they are signed by an authorized key.
1448 @cindex offload test
1449 To test whether your setup is operational, run this command on the
1456 This will attempt to connect to each of the build machines specified in
1457 @file{/etc/guix/machines.scm}, make sure Guix is
1458 available on each machine, attempt to export to the machine and import
1459 from it, and report any error in the process.
1461 If you want to test a different machine file, just specify it on the
1465 # guix offload test machines-qualif.scm
1468 Last, you can test the subset of the machines whose name matches a
1469 regular expression like this:
1472 # guix offload test machines.scm '\.gnu\.org$'
1475 @cindex offload status
1476 To display the current load of all build hosts, run this command on the
1480 # guix offload status
1484 @node SELinux Support
1485 @subsection SELinux Support
1487 @cindex SELinux, daemon policy
1488 @cindex mandatory access control, SELinux
1489 @cindex security, guix-daemon
1490 Guix includes an SELinux policy file at @file{etc/guix-daemon.cil} that
1491 can be installed on a system where SELinux is enabled, in order to label
1492 Guix files and to specify the expected behavior of the daemon. Since
1493 Guix System does not provide an SELinux base policy, the daemon policy cannot
1494 be used on Guix System.
1496 @subsubsection Installing the SELinux policy
1497 @cindex SELinux, policy installation
1498 To install the policy run this command as root:
1501 semodule -i etc/guix-daemon.cil
1504 Then relabel the file system with @code{restorecon} or by a different
1505 mechanism provided by your system.
1507 Once the policy is installed, the file system has been relabeled, and
1508 the daemon has been restarted, it should be running in the
1509 @code{guix_daemon_t} context. You can confirm this with the following
1513 ps -Zax | grep guix-daemon
1516 Monitor the SELinux log files as you run a command like @code{guix build
1517 hello} to convince yourself that SELinux permits all necessary
1520 @subsubsection Limitations
1521 @cindex SELinux, limitations
1523 This policy is not perfect. Here is a list of limitations or quirks
1524 that should be considered when deploying the provided SELinux policy for
1529 @code{guix_daemon_socket_t} isn’t actually used. None of the socket
1530 operations involve contexts that have anything to do with
1531 @code{guix_daemon_socket_t}. It doesn’t hurt to have this unused label,
1532 but it would be preferable to define socket rules for only this label.
1535 @code{guix gc} cannot access arbitrary links to profiles. By design,
1536 the file label of the destination of a symlink is independent of the
1537 file label of the link itself. Although all profiles under
1538 $localstatedir are labelled, the links to these profiles inherit the
1539 label of the directory they are in. For links in the user’s home
1540 directory this will be @code{user_home_t}. But for links from the root
1541 user’s home directory, or @file{/tmp}, or the HTTP server’s working
1542 directory, etc, this won’t work. @code{guix gc} would be prevented from
1543 reading and following these links.
1546 The daemon’s feature to listen for TCP connections might no longer work.
1547 This might require extra rules, because SELinux treats network sockets
1548 differently from files.
1551 Currently all files with a name matching the regular expression
1552 @code{/gnu/store/.+-(guix-.+|profile)/bin/guix-daemon} are assigned the
1553 label @code{guix_daemon_exec_t}; this means that @emph{any} file with
1554 that name in any profile would be permitted to run in the
1555 @code{guix_daemon_t} domain. This is not ideal. An attacker could
1556 build a package that provides this executable and convince a user to
1557 install and run it, which lifts it into the @code{guix_daemon_t} domain.
1558 At that point SELinux could not prevent it from accessing files that are
1559 allowed for processes in that domain.
1561 You will need to relabel the store directory after all upgrades to
1562 @file{guix-daemon}, such as after running @code{guix pull}. Assuming the
1563 store is in @file{/gnu}, you can do this with @code{restorecon -vR /gnu},
1564 or by other means provided by your operating system.
1566 We could generate a much more restrictive policy at installation time,
1567 so that only the @emph{exact} file name of the currently installed
1568 @code{guix-daemon} executable would be labelled with
1569 @code{guix_daemon_exec_t}, instead of using a broad regular expression.
1570 The downside is that root would have to install or upgrade the policy at
1571 installation time whenever the Guix package that provides the
1572 effectively running @code{guix-daemon} executable is upgraded.
1575 @node Invoking guix-daemon
1576 @section Invoking @command{guix-daemon}
1578 The @command{guix-daemon} program implements all the functionality to
1579 access the store. This includes launching build processes, running the
1580 garbage collector, querying the availability of a build result, etc. It
1581 is normally run as @code{root} like this:
1584 # guix-daemon --build-users-group=guixbuild
1587 @cindex socket activation, for @command{guix-daemon}
1588 This daemon can also be started following the systemd ``socket
1589 activation'' protocol (@pxref{Service De- and Constructors,
1590 @code{make-systemd-constructor},, shepherd, The GNU Shepherd Manual}).
1592 For details on how to set it up, @pxref{Setting Up the Daemon}.
1595 @cindex container, build environment
1596 @cindex build environment
1597 @cindex reproducible builds
1598 By default, @command{guix-daemon} launches build processes under
1599 different UIDs, taken from the build group specified with
1600 @option{--build-users-group}. In addition, each build process is run in a
1601 chroot environment that only contains the subset of the store that the
1602 build process depends on, as specified by its derivation
1603 (@pxref{Programming Interface, derivation}), plus a set of specific
1604 system directories. By default, the latter contains @file{/dev} and
1605 @file{/dev/pts}. Furthermore, on GNU/Linux, the build environment is a
1606 @dfn{container}: in addition to having its own file system tree, it has
1607 a separate mount name space, its own PID name space, network name space,
1608 etc. This helps achieve reproducible builds (@pxref{Features}).
1610 When the daemon performs a build on behalf of the user, it creates a
1611 build directory under @file{/tmp} or under the directory specified by
1612 its @env{TMPDIR} environment variable. This directory is shared with
1613 the container for the duration of the build, though within the container,
1614 the build tree is always called @file{/tmp/guix-build-@var{name}.drv-0}.
1616 The build directory is automatically deleted upon completion, unless the
1617 build failed and the client specified @option{--keep-failed}
1618 (@pxref{Common Build Options, @option{--keep-failed}}).
1620 The daemon listens for connections and spawns one sub-process for each session
1621 started by a client (one of the @command{guix} sub-commands). The
1622 @command{guix processes} command allows you to get an overview of the activity
1623 on your system by viewing each of the active sessions and clients.
1624 @xref{Invoking guix processes}, for more information.
1626 The following command-line options are supported:
1629 @item --build-users-group=@var{group}
1630 Take users from @var{group} to run build processes (@pxref{Setting Up
1631 the Daemon, build users}).
1633 @item --no-substitutes
1635 Do not use substitutes for build products. That is, always build things
1636 locally instead of allowing downloads of pre-built binaries
1637 (@pxref{Substitutes}).
1639 When the daemon runs with @option{--no-substitutes}, clients can still
1640 explicitly enable substitution @i{via} the @code{set-build-options}
1641 remote procedure call (@pxref{The Store}).
1643 @anchor{daemon-substitute-urls}
1644 @item --substitute-urls=@var{urls}
1645 Consider @var{urls} the default whitespace-separated list of substitute
1646 source URLs. When this option is omitted,
1647 @indicateurl{@value{SUBSTITUTE-URLS}} is used.
1649 This means that substitutes may be downloaded from @var{urls}, as long
1650 as they are signed by a trusted signature (@pxref{Substitutes}).
1652 @xref{Getting Substitutes from Other Servers}, for more information on
1653 how to configure the daemon to get substitutes from other servers.
1657 Do not use offload builds to other machines (@pxref{Daemon Offload
1658 Setup}). That is, always build things locally instead of offloading
1659 builds to remote machines.
1661 @item --cache-failures
1662 Cache build failures. By default, only successful builds are cached.
1664 When this option is used, @command{guix gc --list-failures} can be used
1665 to query the set of store items marked as failed; @command{guix gc
1666 --clear-failures} removes store items from the set of cached failures.
1667 @xref{Invoking guix gc}.
1669 @item --cores=@var{n}
1671 Use @var{n} CPU cores to build each derivation; @code{0} means as many
1674 The default value is @code{0}, but it may be overridden by clients, such
1675 as the @option{--cores} option of @command{guix build} (@pxref{Invoking
1678 The effect is to define the @env{NIX_BUILD_CORES} environment variable
1679 in the build process, which can then use it to exploit internal
1680 parallelism---for instance, by running @code{make -j$NIX_BUILD_CORES}.
1682 @item --max-jobs=@var{n}
1684 Allow at most @var{n} build jobs in parallel. The default value is
1685 @code{1}. Setting it to @code{0} means that no builds will be performed
1686 locally; instead, the daemon will offload builds (@pxref{Daemon Offload
1687 Setup}), or simply fail.
1689 @item --max-silent-time=@var{seconds}
1690 When the build or substitution process remains silent for more than
1691 @var{seconds}, terminate it and report a build failure.
1693 The default value is @code{0}, which disables the timeout.
1695 The value specified here can be overridden by clients (@pxref{Common
1696 Build Options, @option{--max-silent-time}}).
1698 @item --timeout=@var{seconds}
1699 Likewise, when the build or substitution process lasts for more than
1700 @var{seconds}, terminate it and report a build failure.
1702 The default value is @code{0}, which disables the timeout.
1704 The value specified here can be overridden by clients (@pxref{Common
1705 Build Options, @option{--timeout}}).
1707 @item --rounds=@var{N}
1708 Build each derivation @var{n} times in a row, and raise an error if
1709 consecutive build results are not bit-for-bit identical. Note that this
1710 setting can be overridden by clients such as @command{guix build}
1711 (@pxref{Invoking guix build}).
1713 When used in conjunction with @option{--keep-failed}, the differing
1714 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
1715 This makes it easy to look for differences between the two results.
1718 Produce debugging output.
1720 This is useful to debug daemon start-up issues, but then it may be
1721 overridden by clients, for example the @option{--verbosity} option of
1722 @command{guix build} (@pxref{Invoking guix build}).
1724 @item --chroot-directory=@var{dir}
1725 Add @var{dir} to the build chroot.
1727 Doing this may change the result of build processes---for instance if
1728 they use optional dependencies found in @var{dir} when it is available,
1729 and not otherwise. For that reason, it is not recommended to do so.
1730 Instead, make sure that each derivation declares all the inputs that it
1733 @item --disable-chroot
1734 Disable chroot builds.
1736 Using this option is not recommended since, again, it would allow build
1737 processes to gain access to undeclared dependencies. It is necessary,
1738 though, when @command{guix-daemon} is running under an unprivileged user
1741 @item --log-compression=@var{type}
1742 Compress build logs according to @var{type}, one of @code{gzip},
1743 @code{bzip2}, or @code{none}.
1745 Unless @option{--lose-logs} is used, all the build logs are kept in the
1746 @var{localstatedir}. To save space, the daemon automatically compresses
1747 them with gzip by default.
1749 @item --discover[=yes|no]
1750 Whether to discover substitute servers on the local network using mDNS
1753 This feature is still experimental. However, here are a few
1758 It might be faster/less expensive than fetching from remote servers;
1760 There are no security risks, only genuine substitutes will be used
1761 (@pxref{Substitute Authentication});
1763 An attacker advertising @command{guix publish} on your LAN cannot serve
1764 you malicious binaries, but they can learn what software you’re
1767 Servers may serve substitute over HTTP, unencrypted, so anyone on the
1768 LAN can see what software you’re installing.
1771 It is also possible to enable or disable substitute server discovery at
1772 run-time by running:
1775 herd discover guix-daemon on
1776 herd discover guix-daemon off
1779 @item --disable-deduplication
1780 @cindex deduplication
1781 Disable automatic file ``deduplication'' in the store.
1783 By default, files added to the store are automatically ``deduplicated'':
1784 if a newly added file is identical to another one found in the store,
1785 the daemon makes the new file a hard link to the other file. This can
1786 noticeably reduce disk usage, at the expense of slightly increased
1787 input/output load at the end of a build process. This option disables
1790 @item --gc-keep-outputs[=yes|no]
1791 Tell whether the garbage collector (GC) must keep outputs of live
1795 @cindex garbage collector roots
1796 When set to @code{yes}, the GC will keep the outputs of any live
1797 derivation available in the store---the @file{.drv} files. The default
1798 is @code{no}, meaning that derivation outputs are kept only if they are
1799 reachable from a GC root. @xref{Invoking guix gc}, for more on GC
1802 @item --gc-keep-derivations[=yes|no]
1803 Tell whether the garbage collector (GC) must keep derivations
1804 corresponding to live outputs.
1806 When set to @code{yes}, as is the case by default, the GC keeps
1807 derivations---i.e., @file{.drv} files---as long as at least one of their
1808 outputs is live. This allows users to keep track of the origins of
1809 items in their store. Setting it to @code{no} saves a bit of disk
1812 In this way, setting @option{--gc-keep-derivations} to @code{yes} causes
1813 liveness to flow from outputs to derivations, and setting
1814 @option{--gc-keep-outputs} to @code{yes} causes liveness to flow from
1815 derivations to outputs. When both are set to @code{yes}, the effect is
1816 to keep all the build prerequisites (the sources, compiler, libraries,
1817 and other build-time tools) of live objects in the store, regardless of
1818 whether these prerequisites are reachable from a GC root. This is
1819 convenient for developers since it saves rebuilds or downloads.
1821 @item --impersonate-linux-2.6
1822 On Linux-based systems, impersonate Linux 2.6. This means that the
1823 kernel's @command{uname} system call will report 2.6 as the release number.
1825 This might be helpful to build programs that (usually wrongfully) depend
1826 on the kernel version number.
1829 Do not keep build logs. By default they are kept under
1830 @file{@var{localstatedir}/guix/log}.
1832 @item --system=@var{system}
1833 Assume @var{system} as the current system type. By default it is the
1834 architecture/kernel pair found at configure time, such as
1835 @code{x86_64-linux}.
1837 @item --listen=@var{endpoint}
1838 Listen for connections on @var{endpoint}. @var{endpoint} is interpreted
1839 as the file name of a Unix-domain socket if it starts with
1840 @code{/} (slash sign). Otherwise, @var{endpoint} is interpreted as a
1841 host name or host name and port to listen to. Here are a few examples:
1844 @item --listen=/gnu/var/daemon
1845 Listen for connections on the @file{/gnu/var/daemon} Unix-domain socket,
1846 creating it if needed.
1848 @item --listen=localhost
1849 @cindex daemon, remote access
1850 @cindex remote access to the daemon
1851 @cindex daemon, cluster setup
1852 @cindex clusters, daemon setup
1853 Listen for TCP connections on the network interface corresponding to
1854 @code{localhost}, on port 44146.
1856 @item --listen=128.0.0.42:1234
1857 Listen for TCP connections on the network interface corresponding to
1858 @code{128.0.0.42}, on port 1234.
1861 This option can be repeated multiple times, in which case
1862 @command{guix-daemon} accepts connections on all the specified
1863 endpoints. Users can tell client commands what endpoint to connect to
1864 by setting the @env{GUIX_DAEMON_SOCKET} environment variable
1865 (@pxref{The Store, @env{GUIX_DAEMON_SOCKET}}).
1868 The daemon protocol is @emph{unauthenticated and unencrypted}. Using
1869 @option{--listen=@var{host}} is suitable on local networks, such as
1870 clusters, where only trusted nodes may connect to the build daemon. In
1871 other cases where remote access to the daemon is needed, we recommend
1872 using Unix-domain sockets along with SSH.
1875 When @option{--listen} is omitted, @command{guix-daemon} listens for
1876 connections on the Unix-domain socket located at
1877 @file{@var{localstatedir}/guix/daemon-socket/socket}.
1881 @node Application Setup
1882 @section Application Setup
1884 @cindex foreign distro
1885 When using Guix on top of GNU/Linux distribution other than Guix System---a
1886 so-called @dfn{foreign distro}---a few additional steps are needed to
1887 get everything in place. Here are some of them.
1891 @anchor{locales-and-locpath}
1892 @cindex locales, when not on Guix System
1894 @vindex GUIX_LOCPATH
1895 Packages installed @i{via} Guix will not use the locale data of the
1896 host system. Instead, you must first install one of the locale packages
1897 available with Guix and then define the @env{GUIX_LOCPATH} environment
1901 $ guix install glibc-locales
1902 $ export GUIX_LOCPATH=$HOME/.guix-profile/lib/locale
1905 Note that the @code{glibc-locales} package contains data for all the
1906 locales supported by the GNU@tie{}libc and weighs in at around
1907 930@tie{}MiB@footnote{The size of the @code{glibc-locales} package is
1908 reduced down to about 213@tie{}MiB with store deduplication and further
1909 down to about 67@tie{}MiB when using a zstd-compressed Btrfs file
1910 system.}. If you only need a few locales, you can define your custom
1911 locales package via the @code{make-glibc-utf8-locales} procedure from
1912 the @code{(gnu packages base)} module. The following example defines a
1913 package containing the various Canadian UTF-8 locales known to the
1914 GNU@tie{}libc, that weighs around 14@tie{}MiB:
1917 (use-modules (gnu packages base))
1919 (define my-glibc-locales
1920 (make-glibc-utf8-locales
1922 #:locales (list "en_CA" "fr_CA" "ik_CA" "iu_CA" "shs_CA")
1923 #:name "glibc-canadian-utf8-locales"))
1926 The @env{GUIX_LOCPATH} variable plays a role similar to @env{LOCPATH}
1927 (@pxref{Locale Names, @env{LOCPATH},, libc, The GNU C Library Reference
1928 Manual}). There are two important differences though:
1932 @env{GUIX_LOCPATH} is honored only by the libc in Guix, and not by the libc
1933 provided by foreign distros. Thus, using @env{GUIX_LOCPATH} allows you
1934 to make sure the programs of the foreign distro will not end up loading
1935 incompatible locale data.
1938 libc suffixes each entry of @env{GUIX_LOCPATH} with @code{/X.Y}, where
1939 @code{X.Y} is the libc version---e.g., @code{2.22}. This means that,
1940 should your Guix profile contain a mixture of programs linked against
1941 different libc version, each libc version will only try to load locale
1942 data in the right format.
1945 This is important because the locale data format used by different libc
1946 versions may be incompatible.
1948 @subsection Name Service Switch
1950 @cindex name service switch, glibc
1951 @cindex NSS (name service switch), glibc
1952 @cindex nscd (name service caching daemon)
1953 @cindex name service caching daemon (nscd)
1954 When using Guix on a foreign distro, we @emph{strongly recommend} that
1955 the system run the GNU C library's @dfn{name service cache daemon},
1956 @command{nscd}, which should be listening on the
1957 @file{/var/run/nscd/socket} socket. Failing to do that, applications
1958 installed with Guix may fail to look up host names or user accounts, or
1959 may even crash. The next paragraphs explain why.
1961 @cindex @file{nsswitch.conf}
1962 The GNU C library implements a @dfn{name service switch} (NSS), which is
1963 an extensible mechanism for ``name lookups'' in general: host name
1964 resolution, user accounts, and more (@pxref{Name Service Switch,,, libc,
1965 The GNU C Library Reference Manual}).
1967 @cindex Network information service (NIS)
1968 @cindex NIS (Network information service)
1969 Being extensible, the NSS supports @dfn{plugins}, which provide new name
1970 lookup implementations: for example, the @code{nss-mdns} plugin allow
1971 resolution of @code{.local} host names, the @code{nis} plugin allows
1972 user account lookup using the Network information service (NIS), and so
1973 on. These extra ``lookup services'' are configured system-wide in
1974 @file{/etc/nsswitch.conf}, and all the programs running on the system
1975 honor those settings (@pxref{NSS Configuration File,,, libc, The GNU C
1978 When they perform a name lookup---for instance by calling the
1979 @code{getaddrinfo} function in C---applications first try to connect to
1980 the nscd; on success, nscd performs name lookups on their behalf. If
1981 the nscd is not running, then they perform the name lookup by
1982 themselves, by loading the name lookup services into their own address
1983 space and running it. These name lookup services---the
1984 @file{libnss_*.so} files---are @code{dlopen}'d, but they may come from
1985 the host system's C library, rather than from the C library the
1986 application is linked against (the C library coming from Guix).
1988 And this is where the problem is: if your application is linked against
1989 Guix's C library (say, glibc 2.24) and tries to load NSS plugins from
1990 another C library (say, @code{libnss_mdns.so} for glibc 2.22), it will
1991 likely crash or have its name lookups fail unexpectedly.
1993 Running @command{nscd} on the system, among other advantages, eliminates
1994 this binary incompatibility problem because those @code{libnss_*.so}
1995 files are loaded in the @command{nscd} process, not in applications
1998 @subsection X11 Fonts
2001 The majority of graphical applications use Fontconfig to locate and load
2002 fonts and perform X11-client-side rendering. The @code{fontconfig}
2003 package in Guix looks for fonts in @file{$HOME/.guix-profile} by
2004 default. Thus, to allow graphical applications installed with Guix to
2005 display fonts, you have to install fonts with Guix as well. Essential
2006 font packages include @code{font-ghostscript}, @code{font-dejavu}, and
2007 @code{font-gnu-freefont}.
2009 @cindex @code{fc-cache}
2011 Once you have installed or removed fonts, or when you notice an
2012 application that does not find fonts, you may need to install Fontconfig
2013 and to force an update of its font cache by running:
2016 guix install fontconfig
2020 To display text written in Chinese languages, Japanese, or Korean in
2021 graphical applications, consider installing
2022 @code{font-adobe-source-han-sans} or @code{font-wqy-zenhei}. The former
2023 has multiple outputs, one per language family (@pxref{Packages with
2024 Multiple Outputs}). For instance, the following command installs fonts
2025 for Chinese languages:
2028 guix install font-adobe-source-han-sans:cn
2031 @cindex @code{xterm}
2032 Older programs such as @command{xterm} do not use Fontconfig and instead
2033 rely on server-side font rendering. Such programs require to specify a
2034 full name of a font using XLFD (X Logical Font Description), like this:
2037 -*-dejavu sans-medium-r-normal-*-*-100-*-*-*-*-*-1
2040 To be able to use such full names for the TrueType fonts installed in
2041 your Guix profile, you need to extend the font path of the X server:
2043 @c Note: 'xset' does not accept symlinks so the trick below arranges to
2044 @c get at the real directory. See <https://bugs.gnu.org/30655>.
2046 xset +fp $(dirname $(readlink -f ~/.guix-profile/share/fonts/truetype/fonts.dir))
2049 @cindex @code{xlsfonts}
2050 After that, you can run @code{xlsfonts} (from @code{xlsfonts} package)
2051 to make sure your TrueType fonts are listed there.
2054 @subsection X.509 Certificates
2056 @cindex @code{nss-certs}
2057 The @code{nss-certs} package provides X.509 certificates, which allow
2058 programs to authenticate Web servers accessed over HTTPS.
2060 When using Guix on a foreign distro, you can install this package and
2061 define the relevant environment variables so that packages know where to
2062 look for certificates. @xref{X.509 Certificates}, for detailed
2065 @subsection Emacs Packages
2067 @cindex @code{emacs}
2068 When you install Emacs packages with Guix, the Elisp files are placed
2069 under the @file{share/emacs/site-lisp/} directory of the profile in
2070 which they are installed. The Elisp libraries are made available to
2071 Emacs through the @env{EMACSLOADPATH} environment variable, which is
2072 set when installing Emacs itself.
2074 Additionally, autoload definitions are automatically evaluated at the
2075 initialization of Emacs, by the Guix-specific
2076 @code{guix-emacs-autoload-packages} procedure. If, for some reason, you
2077 want to avoid auto-loading the Emacs packages installed with Guix, you
2078 can do so by running Emacs with the @option{--no-site-file} option
2079 (@pxref{Init File,,, emacs, The GNU Emacs Manual}).
2082 @node Upgrading Guix
2083 @section Upgrading Guix
2085 @cindex Upgrading Guix, on a foreign distro
2087 To upgrade Guix, run:
2093 @xref{Invoking guix pull}, for more information.
2095 @cindex upgrading Guix for the root user, on a foreign distro
2096 @cindex upgrading the Guix daemon, on a foreign distro
2097 @cindex @command{guix pull} for the root user, on a foreign distro
2099 On a foreign distro, you can upgrade the build daemon by running:
2106 followed by (assuming your distro uses the systemd service management
2110 systemctl restart guix-daemon.service
2113 On Guix System, upgrading the daemon is achieved by reconfiguring the
2114 system (@pxref{Invoking guix system, @code{guix system reconfigure}}).
2118 @c *********************************************************************
2119 @node System Installation
2120 @chapter System Installation
2122 @cindex installing Guix System
2123 @cindex Guix System, installation
2124 This section explains how to install Guix System
2125 on a machine. Guix, as a package manager, can
2126 also be installed on top of a running GNU/Linux system,
2127 @pxref{Installation}.
2131 @c This paragraph is for people reading this from tty2 of the
2132 @c installation image.
2133 You are reading this documentation with an Info reader. For details on
2134 how to use it, hit the @key{RET} key (``return'' or ``enter'') on the
2135 link that follows: @pxref{Top, Info reader,, info-stnd, Stand-alone GNU
2136 Info}. Hit @kbd{l} afterwards to come back here.
2138 Alternatively, run @command{info info} in another tty to keep the manual
2144 * Limitations:: What you can expect.
2145 * Hardware Considerations:: Supported hardware.
2146 * USB Stick and DVD Installation:: Preparing the installation medium.
2147 * Preparing for Installation:: Networking, partitioning, etc.
2148 * Guided Graphical Installation:: Easy graphical installation.
2149 * Manual Installation:: Manual installation for wizards.
2150 * After System Installation:: When installation succeeded.
2151 * Installing Guix in a VM:: Guix System playground.
2152 * Building the Installation Image:: How this comes to be.
2156 @section Limitations
2158 We consider Guix System to be ready for a wide range of ``desktop'' and server
2159 use cases. The reliability guarantees it provides---transactional upgrades
2160 and rollbacks, reproducibility---make it a solid foundation.
2162 Nevertheless, before you proceed with the installation, be aware of the
2163 following noteworthy limitations applicable to version @value{VERSION}:
2167 More and more system services are provided (@pxref{Services}), but some
2171 GNOME, Xfce, LXDE, and Enlightenment are available (@pxref{Desktop Services}),
2172 as well as a number of X11 window managers. However, KDE is currently
2176 More than a disclaimer, this is an invitation to report issues (and success
2177 stories!), and to join us in improving it. @xref{Contributing}, for more
2181 @node Hardware Considerations
2182 @section Hardware Considerations
2184 @cindex hardware support on Guix System
2185 GNU@tie{}Guix focuses on respecting the user's computing freedom. It
2186 builds around the kernel Linux-libre, which means that only hardware for
2187 which free software drivers and firmware exist is supported. Nowadays,
2188 a wide range of off-the-shelf hardware is supported on
2189 GNU/Linux-libre---from keyboards to graphics cards to scanners and
2190 Ethernet controllers. Unfortunately, there are still areas where
2191 hardware vendors deny users control over their own computing, and such
2192 hardware is not supported on Guix System.
2194 @cindex WiFi, hardware support
2195 One of the main areas where free drivers or firmware are lacking is WiFi
2196 devices. WiFi devices known to work include those using Atheros chips
2197 (AR9271 and AR7010), which corresponds to the @code{ath9k} Linux-libre
2198 driver, and those using Broadcom/AirForce chips (BCM43xx with
2199 Wireless-Core Revision 5), which corresponds to the @code{b43-open}
2200 Linux-libre driver. Free firmware exists for both and is available
2201 out-of-the-box on Guix System, as part of @code{%base-firmware}
2202 (@pxref{operating-system Reference, @code{firmware}}).
2204 @cindex RYF, Respects Your Freedom
2205 The @uref{https://www.fsf.org/, Free Software Foundation} runs
2206 @uref{https://www.fsf.org/ryf, @dfn{Respects Your Freedom}} (RYF), a
2207 certification program for hardware products that respect your freedom
2208 and your privacy and ensure that you have control over your device. We
2209 encourage you to check the list of RYF-certified devices.
2211 Another useful resource is the @uref{https://www.h-node.org/, H-Node}
2212 web site. It contains a catalog of hardware devices with information
2213 about their support in GNU/Linux.
2216 @node USB Stick and DVD Installation
2217 @section USB Stick and DVD Installation
2219 An ISO-9660 installation image that can be written to a USB stick or
2220 burnt to a DVD can be downloaded from
2221 @indicateurl{@value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso},
2222 where you can replace @code{x86_64-linux} with one of:
2226 for a GNU/Linux system on Intel/AMD-compatible 64-bit CPUs;
2229 for a 32-bit GNU/Linux system on Intel-compatible CPUs.
2232 @c start duplication of authentication part from ``Binary Installation''
2233 Make sure to download the associated @file{.sig} file and to verify the
2234 authenticity of the image against it, along these lines:
2237 $ wget @value{BASE-URL}/guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
2238 $ gpg --verify guix-system-install-@value{VERSION}.x86_64-linux.iso.sig
2241 If that command fails because you do not have the required public key,
2242 then run this command to import it:
2245 $ wget @value{OPENPGP-SIGNING-KEY-URL} \
2246 -qO - | gpg --import -
2250 and rerun the @code{gpg --verify} command.
2252 Take note that a warning like ``This key is not certified with a trusted
2253 signature!'' is normal.
2257 This image contains the tools necessary for an installation.
2258 It is meant to be copied @emph{as is} to a large-enough USB stick or DVD.
2260 @unnumberedsubsec Copying to a USB Stick
2262 Insert a USB stick of 1@tie{}GiB or more into your machine, and determine
2263 its device name. Assuming that the USB stick is known as @file{/dev/sdX},
2264 copy the image with:
2267 dd if=guix-system-install-@value{VERSION}.x86_64-linux.iso of=/dev/sdX status=progress
2271 Access to @file{/dev/sdX} usually requires root privileges.
2273 @unnumberedsubsec Burning on a DVD
2275 Insert a blank DVD into your machine, and determine
2276 its device name. Assuming that the DVD drive is known as @file{/dev/srX},
2277 copy the image with:
2280 growisofs -dvd-compat -Z /dev/srX=guix-system-install-@value{VERSION}.x86_64-linux.iso
2283 Access to @file{/dev/srX} usually requires root privileges.
2285 @unnumberedsubsec Booting
2287 Once this is done, you should be able to reboot the system and boot from
2288 the USB stick or DVD@. The latter usually requires you to get in the
2289 BIOS or UEFI boot menu, where you can choose to boot from the USB stick.
2290 In order to boot from Libreboot, switch to the command mode by pressing
2291 the @kbd{c} key and type @command{search_grub usb}.
2293 @xref{Installing Guix in a VM}, if, instead, you would like to install
2294 Guix System in a virtual machine (VM).
2297 @node Preparing for Installation
2298 @section Preparing for Installation
2300 Once you have booted, you can use the guided graphical installer, which makes
2301 it easy to get started (@pxref{Guided Graphical Installation}). Alternatively,
2302 if you are already familiar with GNU/Linux and if you want more control than
2303 what the graphical installer provides, you can choose the ``manual''
2304 installation process (@pxref{Manual Installation}).
2306 The graphical installer is available on TTY1. You can obtain root shells on
2307 TTYs 3 to 6 by hitting @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, etc. TTY2 shows
2308 this documentation and you can reach it with @kbd{ctrl-alt-f2}. Documentation
2309 is browsable using the Info reader commands (@pxref{Top,,, info-stnd,
2310 Stand-alone GNU Info}). The installation system runs the GPM mouse daemon,
2311 which allows you to select text with the left mouse button and to paste it
2312 with the middle button.
2315 Installation requires access to the Internet so that any missing
2316 dependencies of your system configuration can be downloaded. See the
2317 ``Networking'' section below.
2320 @node Guided Graphical Installation
2321 @section Guided Graphical Installation
2323 The graphical installer is a text-based user interface. It will guide you,
2324 with dialog boxes, through the steps needed to install GNU@tie{}Guix System.
2326 The first dialog boxes allow you to set up the system as you use it during the
2327 installation: you can choose the language, keyboard layout, and set up
2328 networking, which will be used during the installation. The image below shows
2329 the networking dialog.
2331 @image{images/installer-network,5in,, networking setup with the graphical installer}
2333 Later steps allow you to partition your hard disk, as shown in the image
2334 below, to choose whether or not to use encrypted file systems, to enter the
2335 host name and root password, and to create an additional account, among other
2338 @image{images/installer-partitions,5in,, partitioning with the graphical installer}
2340 Note that, at any time, the installer allows you to exit the current
2341 installation step and resume at a previous step, as show in the image below.
2343 @image{images/installer-resume,5in,, resuming the installation process}
2345 Once you're done, the installer produces an operating system configuration and
2346 displays it (@pxref{Using the Configuration System}). At that point you can
2347 hit ``OK'' and installation will proceed. On success, you can reboot into the
2348 new system and enjoy. @xref{After System Installation}, for what's next!
2351 @node Manual Installation
2352 @section Manual Installation
2354 This section describes how you would ``manually'' install GNU@tie{}Guix System
2355 on your machine. This option requires familiarity with GNU/Linux, with the
2356 shell, and with common administration tools. If you think this is not for
2357 you, consider using the guided graphical installer (@pxref{Guided Graphical
2360 The installation system provides root shells on TTYs 3 to 6; press
2361 @kbd{ctrl-alt-f3}, @kbd{ctrl-alt-f4}, and so on to reach them. It includes
2362 many common tools needed to install the system, but is also a full-blown
2363 Guix System. This means that you can install additional packages, should you
2364 need it, using @command{guix package} (@pxref{Invoking guix package}).
2367 * Keyboard Layout and Networking and Partitioning:: Initial setup.
2368 * Proceeding with the Installation:: Installing.
2371 @node Keyboard Layout and Networking and Partitioning
2372 @subsection Keyboard Layout, Networking, and Partitioning
2374 Before you can install the system, you may want to adjust the keyboard layout,
2375 set up networking, and partition your target hard disk. This section will
2376 guide you through this.
2378 @subsubsection Keyboard Layout
2380 @cindex keyboard layout
2381 The installation image uses the US qwerty keyboard layout. If you want
2382 to change it, you can use the @command{loadkeys} command. For example,
2383 the following command selects the Dvorak keyboard layout:
2389 See the files under @file{/run/current-system/profile/share/keymaps} for
2390 a list of available keyboard layouts. Run @command{man loadkeys} for
2393 @anchor{manual-installation-networking}
2394 @subsubsection Networking
2396 Run the following command to see what your network interfaces are called:
2403 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2409 @c https://cgit.freedesktop.org/systemd/systemd/tree/src/udev/udev-builtin-net_id.c#n20
2410 Wired interfaces have a name starting with @samp{e}; for example, the
2411 interface corresponding to the first on-board Ethernet controller is
2412 called @samp{eno1}. Wireless interfaces have a name starting with
2413 @samp{w}, like @samp{w1p2s0}.
2416 @item Wired connection
2417 To configure a wired network run the following command, substituting
2418 @var{interface} with the name of the wired interface you want to use.
2421 ifconfig @var{interface} up
2425 @dots{} or, using the GNU/Linux-specific @command{ip} command:
2428 ip link set @var{interface} up
2431 @item Wireless connection
2434 To configure wireless networking, you can create a configuration file
2435 for the @command{wpa_supplicant} configuration tool (its location is not
2436 important) using one of the available text editors such as
2440 nano wpa_supplicant.conf
2443 As an example, the following stanza can go to this file and will work
2444 for many wireless networks, provided you give the actual SSID and
2445 passphrase for the network you are connecting to:
2449 ssid="@var{my-ssid}"
2451 psk="the network's secret passphrase"
2455 Start the wireless service and run it in the background with the
2456 following command (substitute @var{interface} with the name of the
2457 network interface you want to use):
2460 wpa_supplicant -c wpa_supplicant.conf -i @var{interface} -B
2463 Run @command{man wpa_supplicant} for more information.
2467 At this point, you need to acquire an IP address. On a network where IP
2468 addresses are automatically assigned @i{via} DHCP, you can run:
2471 dhclient -v @var{interface}
2474 Try to ping a server to see if networking is up and running:
2480 Setting up network access is almost always a requirement because the
2481 image does not contain all the software and tools that may be needed.
2483 @cindex proxy, during system installation
2484 If you need HTTP and HTTPS access to go through a proxy, run the
2488 herd set-http-proxy guix-daemon @var{URL}
2492 where @var{URL} is the proxy URL, for example
2493 @code{http://example.org:8118}.
2495 @cindex installing over SSH
2496 If you want to, you can continue the installation remotely by starting
2500 herd start ssh-daemon
2503 Make sure to either set a password with @command{passwd}, or configure
2504 OpenSSH public key authentication before logging in.
2506 @subsubsection Disk Partitioning
2508 Unless this has already been done, the next step is to partition, and
2509 then format the target partition(s).
2511 The installation image includes several partitioning tools, including
2512 Parted (@pxref{Overview,,, parted, GNU Parted User Manual}),
2513 @command{fdisk}, and @command{cfdisk}. Run it and set up your disk with
2514 the partition layout you want:
2520 If your disk uses the GUID Partition Table (GPT) format and you plan to
2521 install BIOS-based GRUB (which is the default), make sure a BIOS Boot
2522 Partition is available (@pxref{BIOS installation,,, grub, GNU GRUB
2525 @cindex EFI, installation
2526 @cindex UEFI, installation
2527 @cindex ESP, EFI system partition
2528 If you instead wish to use EFI-based GRUB, a FAT32 @dfn{EFI System Partition}
2529 (ESP) is required. This partition can be mounted at @file{/boot/efi} for
2530 instance and must have the @code{esp} flag set. E.g., for @command{parted}:
2533 parted /dev/sda set 1 esp on
2537 @vindex grub-bootloader
2538 @vindex grub-efi-bootloader
2539 Unsure whether to use EFI- or BIOS-based GRUB? If the directory
2540 @file{/sys/firmware/efi} exists in the installation image, then you should
2541 probably perform an EFI installation, using @code{grub-efi-bootloader}.
2542 Otherwise you should use the BIOS-based GRUB, known as
2543 @code{grub-bootloader}. @xref{Bootloader Configuration}, for more info on
2547 Once you are done partitioning the target hard disk drive, you have to
2548 create a file system on the relevant partition(s)@footnote{Currently
2549 Guix System only supports ext4, btrfs, JFS, F2FS, and XFS file systems. In
2550 particular, code that reads file system UUIDs and labels only works for these
2551 file system types.}. For the ESP, if you have one and assuming it is
2552 @file{/dev/sda1}, run:
2555 mkfs.fat -F32 /dev/sda1
2558 For the root file system, ext4 is the most widely used format. Other
2559 file systems, such as Btrfs, support compression, which is reported to
2560 nicely complement file deduplication that the daemon performs
2561 independently of the file system (@pxref{Invoking guix-daemon,
2564 Preferably, assign file systems a label so that you can easily and
2565 reliably refer to them in @code{file-system} declarations (@pxref{File
2566 Systems}). This is typically done using the @code{-L} option of
2567 @command{mkfs.ext4} and related commands. So, assuming the target root
2568 partition lives at @file{/dev/sda2}, a file system with the label
2569 @code{my-root} can be created with:
2572 mkfs.ext4 -L my-root /dev/sda2
2575 @cindex encrypted disk
2576 If you are instead planning to encrypt the root partition, you can use
2577 the Cryptsetup/LUKS utilities to do that (see @inlinefmtifelse{html,
2578 @uref{https://linux.die.net/man/8/cryptsetup, @code{man cryptsetup}},
2579 @code{man cryptsetup}} for more information).
2582 Note that GRUB can unlock LUKS2 devices since version 2.06, but only
2583 supports the PBKDF2 key derivation function, which is not the default
2584 for @command{cryptsetup luksFormat}. You can check which key derivation
2585 function is being used by a device by running @command{cryptsetup
2586 luksDump @var{device}}, and looking for the PBKDF field of your
2590 Assuming you want to store the root partition on @file{/dev/sda2}, the
2591 command sequence to format it as a LUKS2 partition would be along these
2595 cryptsetup luksFormat --type luks2 --pbkdf pbkdf2 /dev/sda2
2596 cryptsetup open /dev/sda2 my-partition
2597 mkfs.ext4 -L my-root /dev/mapper/my-partition
2600 Once that is done, mount the target file system under @file{/mnt}
2601 with a command like (again, assuming @code{my-root} is the label of the
2605 mount LABEL=my-root /mnt
2608 Also mount any other file systems you would like to use on the target
2609 system relative to this path. If you have opted for @file{/boot/efi} as an
2610 EFI mount point for example, mount it at @file{/mnt/boot/efi} now so it is
2611 found by @code{guix system init} afterwards.
2613 Finally, if you plan to use one or more swap partitions (@pxref{Swap
2614 Space}), make sure to initialize them with @command{mkswap}. Assuming
2615 you have one swap partition on @file{/dev/sda3}, you would run:
2622 Alternatively, you may use a swap file. For example, assuming that in
2623 the new system you want to use the file @file{/swapfile} as a swap file,
2624 you would run@footnote{This example will work for many types of file
2625 systems (e.g., ext4). However, for copy-on-write file systems (e.g.,
2626 btrfs), the required steps may be different. For details, see the
2627 manual pages for @command{mkswap} and @command{swapon}.}:
2630 # This is 10 GiB of swap space. Adjust "count" to change the size.
2631 dd if=/dev/zero of=/mnt/swapfile bs=1MiB count=10240
2632 # For security, make the file readable and writable only by root.
2633 chmod 600 /mnt/swapfile
2634 mkswap /mnt/swapfile
2635 swapon /mnt/swapfile
2638 Note that if you have encrypted the root partition and created a swap
2639 file in its file system as described above, then the encryption also
2640 protects the swap file, just like any other file in that file system.
2642 @node Proceeding with the Installation
2643 @subsection Proceeding with the Installation
2645 With the target partitions ready and the target root mounted on
2646 @file{/mnt}, we're ready to go. First, run:
2649 herd start cow-store /mnt
2652 This makes @file{/gnu/store} copy-on-write, such that packages added to it
2653 during the installation phase are written to the target disk on @file{/mnt}
2654 rather than kept in memory. This is necessary because the first phase of
2655 the @command{guix system init} command (see below) entails downloads or
2656 builds to @file{/gnu/store} which, initially, is an in-memory file system.
2658 Next, you have to edit a file and
2659 provide the declaration of the operating system to be installed. To
2660 that end, the installation system comes with three text editors. We
2661 recommend GNU nano (@pxref{Top,,, nano, GNU nano Manual}), which
2662 supports syntax highlighting and parentheses matching; other editors
2663 include mg (an Emacs clone), and
2664 nvi (a clone of the original BSD @command{vi} editor).
2665 We strongly recommend storing that file on the target root file system, say,
2666 as @file{/mnt/etc/config.scm}. Failing to do that, you will have lost your
2667 configuration file once you have rebooted into the newly-installed system.
2669 @xref{Using the Configuration System}, for an overview of the
2670 configuration file. The example configurations discussed in that
2671 section are available under @file{/etc/configuration} in the
2672 installation image. Thus, to get started with a system configuration
2673 providing a graphical display server (a ``desktop'' system), you can run
2674 something along these lines:
2678 # cp /etc/configuration/desktop.scm /mnt/etc/config.scm
2679 # nano /mnt/etc/config.scm
2682 You should pay attention to what your configuration file contains, and
2687 Make sure the @code{bootloader-configuration} form refers to the targets
2688 you want to install GRUB on. It should mention @code{grub-bootloader}
2689 if you are installing GRUB in the legacy way, or
2690 @code{grub-efi-bootloader} for newer UEFI systems. For legacy systems,
2691 the @code{targets} field contain the names of the devices, like
2692 @code{(list "/dev/sda")}; for UEFI systems it names the paths to mounted
2693 EFI partitions, like @code{(list "/boot/efi")}; do make sure the paths
2694 are currently mounted and a @code{file-system} entry is specified in
2698 Be sure that your file system labels match the value of their respective
2699 @code{device} fields in your @code{file-system} configuration, assuming
2700 your @code{file-system} configuration uses the @code{file-system-label}
2701 procedure in its @code{device} field.
2704 If there are encrypted or RAID partitions, make sure to add a
2705 @code{mapped-devices} field to describe them (@pxref{Mapped Devices}).
2708 Once you are done preparing the configuration file, the new system must
2709 be initialized (remember that the target root file system is mounted
2713 guix system init /mnt/etc/config.scm /mnt
2717 This copies all the necessary files and installs GRUB on
2718 @file{/dev/sdX}, unless you pass the @option{--no-bootloader} option. For
2719 more information, @pxref{Invoking guix system}. This command may trigger
2720 downloads or builds of missing packages, which can take some time.
2722 Once that command has completed---and hopefully succeeded!---you can run
2723 @command{reboot} and boot into the new system. The @code{root} password
2724 in the new system is initially empty; other users' passwords need to be
2725 initialized by running the @command{passwd} command as @code{root},
2726 unless your configuration specifies otherwise
2727 (@pxref{user-account-password, user account passwords}).
2728 @xref{After System Installation}, for what's next!
2731 @node After System Installation
2732 @section After System Installation
2734 Success, you've now booted into Guix System! From then on, you can update the
2735 system whenever you want by running, say:
2739 sudo guix system reconfigure /etc/config.scm
2743 This builds a new system generation with the latest packages and services
2744 (@pxref{Invoking guix system}). We recommend doing that regularly so that
2745 your system includes the latest security updates (@pxref{Security Updates}).
2747 @c See <https://lists.gnu.org/archive/html/guix-devel/2019-01/msg00268.html>.
2749 @cindex sudo vs. @command{guix pull}
2750 Note that @command{sudo guix} runs your user's @command{guix} command and
2751 @emph{not} root's, because @command{sudo} leaves @env{PATH} unchanged. To
2752 explicitly run root's @command{guix}, type @command{sudo -i guix @dots{}}.
2754 The difference matters here, because @command{guix pull} updates
2755 the @command{guix} command and package definitions only for the user it is run
2756 as. This means that if you choose to use @command{guix system reconfigure} in
2757 root's login shell, you'll need to @command{guix pull} separately.
2760 Now, @pxref{Getting Started}, and
2761 join us on @code{#guix} on the Libera Chat IRC network or on
2762 @email{guix-devel@@gnu.org} to share your experience!
2765 @node Installing Guix in a VM
2766 @section Installing Guix in a Virtual Machine
2768 @cindex virtual machine, Guix System installation
2769 @cindex virtual private server (VPS)
2770 @cindex VPS (virtual private server)
2771 If you'd like to install Guix System in a virtual machine (VM) or on a
2772 virtual private server (VPS) rather than on your beloved machine, this
2775 To boot a @uref{https://qemu.org/,QEMU} VM for installing Guix System in a
2776 disk image, follow these steps:
2780 First, retrieve and decompress the Guix system installation image as
2781 described previously (@pxref{USB Stick and DVD Installation}).
2784 Create a disk image that will hold the installed system. To make a
2785 qcow2-formatted disk image, use the @command{qemu-img} command:
2788 qemu-img create -f qcow2 guix-system.img 50G
2791 The resulting file will be much smaller than 50 GB (typically less than
2792 1 MB), but it will grow as the virtualized storage device is filled up.
2795 Boot the USB installation image in an VM:
2798 qemu-system-x86_64 -m 1024 -smp 1 -enable-kvm \
2799 -nic user,model=virtio-net-pci -boot menu=on,order=d \
2800 -drive file=guix-system.img \
2801 -drive media=cdrom,file=guix-system-install-@value{VERSION}.@var{system}.iso
2804 @code{-enable-kvm} is optional, but significantly improves performance,
2805 @pxref{Running Guix in a VM}.
2808 You're now root in the VM, proceed with the installation process.
2809 @xref{Preparing for Installation}, and follow the instructions.
2812 Once installation is complete, you can boot the system that's on your
2813 @file{guix-system.img} image. @xref{Running Guix in a VM}, for how to do
2816 @node Building the Installation Image
2817 @section Building the Installation Image
2819 @cindex installation image
2820 The installation image described above was built using the @command{guix
2821 system} command, specifically:
2824 guix system image -t iso9660 gnu/system/install.scm
2827 Have a look at @file{gnu/system/install.scm} in the source tree,
2828 and see also @ref{Invoking guix system} for more information
2829 about the installation image.
2831 @section Building the Installation Image for ARM Boards
2833 Many ARM boards require a specific variant of the
2834 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot} bootloader.
2836 If you build a disk image and the bootloader is not available otherwise
2837 (on another boot drive etc), it's advisable to build an image that
2838 includes the bootloader, specifically:
2841 guix system image --system=armhf-linux -e '((@@ (gnu system install) os-with-u-boot) (@@ (gnu system install) installation-os) "A20-OLinuXino-Lime2")'
2844 @code{A20-OLinuXino-Lime2} is the name of the board. If you specify an invalid
2845 board, a list of possible boards will be printed.
2847 @c *********************************************************************
2848 @cindex troubleshooting, guix system
2849 @cindex guix system troubleshooting
2850 @node System Troubleshooting Tips
2851 @chapter System Troubleshooting Tips
2853 Guix System allows rebooting into a previous generation should the last
2854 one be malfunctioning, which makes it quite robust against being broken
2855 irreversibly. This feature depends on GRUB being correctly functioning
2856 though, which means that if for whatever reasons your GRUB installation
2857 becomes corrupted during a system reconfiguration, you may not be able
2858 to easily boot into a previous generation. A technique that can be used
2859 in this case is to @i{chroot} into your broken system and reconfigure it
2860 from there. Such technique is explained below.
2862 @cindex chroot, guix system
2863 @cindex chrooting, guix system
2864 @cindex repairing GRUB, via chroot
2865 @node Chrooting into an existing system
2866 @section Chrooting into an existing system
2868 This section details how to @i{chroot} to an already installed Guix
2869 System with the aim of reconfiguring it, for example to fix a broken
2870 GRUB installation. The process is similar to how it would be done on
2871 other GNU/Linux systems, but there are some Guix System particularities
2872 such as the daemon and profiles that make it worthy of explaining here.
2876 Obtain a bootable image of Guix System. It is recommended the latest
2877 development snapshot so the kernel and the tools used are at least as as
2878 new as those of your installed system; it can be retrieved from the
2879 @url{https://ci.guix.gnu.org/search/latest/ISO-9660?query=spec:images+status:success+system:x86_64-linux+image.iso,
2880 https://ci.guix.gnu.org} URL. Follow the @pxref{USB Stick and DVD
2881 Installation} section for copying it to a bootable media.
2884 Boot the image, and proceed with the graphical text-based installer
2885 until your network is configured. Alternatively, you could configure
2886 the network manually by following the
2887 @ref{manual-installation-networking} section. If you get the error
2888 @samp{RTNETLINK answers: Operation not possible due to RF-kill}, try
2889 @samp{rfkill list} followed by @samp{rfkill unblock 0}, where @samp{0}
2890 is your device identifier (ID).
2893 Switch to a virtual console (tty) if you haven't already by pressing
2894 simultaneously the @kbd{Control + Alt + F4} keys. Mount your file
2895 system at @file{/mnt}. Assuming your root partition is
2896 @file{/dev/sda2}, you would do:
2899 mount /dev/sda2 /mnt
2903 Mount special block devices and Linux-specific directories:
2906 mount --bind /proc /mnt/proc
2907 mount --bind /sys /mnt/sys
2908 mount --bind /dev /mnt/dev
2911 If your system is EFI-based, you must also mount the ESP partition.
2912 Assuming it is @file{/dev/sda1}, you can do so with:
2915 mount /dev/sda1 /mnt/boot/efi
2919 Enter your system via chroot:
2926 Source your @var{user} profile to setup the environment, where
2927 @var{user} is the user name used for the Guix System you are attempting
2931 source /home/@var{user}/.guix-profile/etc/profile
2934 To ensure you are working with the Guix revision you normally would as
2935 your normal user, also source your current Guix profile:
2938 source /home/@var{user}/.config/guix/current/etc/profile
2942 Start a minimal @command{guix-daemon} in the background:
2945 guix-daemon --build-users-group=guixbuild --disable-chroot &
2949 Edit your Guix System configuration if needed, then reconfigure with:
2952 guix system reconfigure your-config.scm
2956 Finally, you should be good to reboot the system to test your fix.
2960 @c *********************************************************************
2961 @node Getting Started
2962 @chapter Getting Started
2964 Presumably, you've reached this section because either you have
2965 installed Guix on top of another distribution (@pxref{Installation}), or
2966 you've installed the standalone Guix System (@pxref{System
2967 Installation}). It's time for you to get started using Guix and this
2968 section aims to help you do that and give you a feel of what it's like.
2970 Guix is about installing software, so probably the first thing you'll
2971 want to do is to actually look for software. Let's say you're looking
2972 for a text editor, you can run:
2975 guix search text editor
2978 This command shows you a number of matching @dfn{packages}, each time
2979 showing the package's name, version, a description, and additional info.
2980 Once you've found out the one you want to use, let's say Emacs (ah ha!),
2981 you can go ahead and install it (run this command as a regular user,
2982 @emph{no need for root privileges}!):
2989 You've installed your first package, congrats! The package is now
2990 visible in your default @dfn{profile}, @file{$HOME/.guix-profile}---a
2991 profile is a directory containing installed packages.
2992 In the process, you've
2993 probably noticed that Guix downloaded pre-built binaries; or, if you
2994 explicitly chose to @emph{not} use pre-built binaries, then probably
2995 Guix is still building software (@pxref{Substitutes}, for more info).
2997 Unless you're using Guix System, the @command{guix install} command must
2998 have printed this hint:
3001 hint: Consider setting the necessary environment variables by running:
3003 GUIX_PROFILE="$HOME/.guix-profile"
3004 . "$GUIX_PROFILE/etc/profile"
3006 Alternately, see `guix package --search-paths -p "$HOME/.guix-profile"'.
3009 Indeed, you must now tell your shell where @command{emacs} and other
3010 programs installed with Guix are to be found. Pasting the two lines
3011 above will do just that: it will add
3012 @code{$HOME/.guix-profile/bin}---which is where the installed package
3013 is---to the @code{PATH} environment variable. You can paste these two
3014 lines in your shell so they take effect right away, but more importantly
3015 you should add them to @file{~/.bash_profile} (or equivalent file if you
3016 do not use Bash) so that environment variables are set next time you
3017 spawn a shell. You only need to do this once and other search paths
3018 environment variables will be taken care of similarly---e.g., if you
3019 eventually install @code{python} and Python libraries,
3020 @env{GUIX_PYTHONPATH} will be defined.
3022 You can go on installing packages at your will. To list installed
3026 guix package --list-installed
3029 To remove a package, you would unsurprisingly run @command{guix remove}.
3030 A distinguishing feature is the ability to @dfn{roll back} any operation
3031 you made---installation, removal, upgrade---by simply typing:
3034 guix package --roll-back
3037 This is because each operation is in fact a @dfn{transaction} that
3038 creates a new @dfn{generation}. These generations and the difference
3039 between them can be displayed by running:
3042 guix package --list-generations
3045 Now you know the basics of package management!
3047 @quotation Going further
3048 @xref{Package Management}, for more about package management. You may
3049 like @dfn{declarative} package management with @command{guix package
3050 --manifest}, managing separate @dfn{profiles} with @option{--profile},
3051 deleting old generations, collecting garbage, and other nifty features
3052 that will come in handy as you become more familiar with Guix. If you
3053 are a developer, @pxref{Development} for additional tools. And if
3054 you're curious, @pxref{Features}, to peek under the hood.
3057 Once you've installed a set of packages, you will want to periodically
3058 @emph{upgrade} them to the latest and greatest version. To do that, you
3059 will first pull the latest revision of Guix and its package collection:
3065 The end result is a new @command{guix} command, under
3066 @file{~/.config/guix/current/bin}. Unless you're on Guix System, the
3067 first time you run @command{guix pull}, be sure to follow the hint that
3068 the command prints and, similar to what we saw above, paste these two
3069 lines in your terminal and @file{.bash_profile}:
3072 GUIX_PROFILE="$HOME/.config/guix/current"
3073 . "$GUIX_PROFILE/etc/profile"
3077 You must also instruct your shell to point to this new @command{guix}:
3083 At this point, you're running a brand new Guix. You can thus go ahead
3084 and actually upgrade all the packages you previously installed:
3090 As you run this command, you will see that binaries are downloaded (or
3091 perhaps some packages are built), and eventually you end up with the
3092 upgraded packages. Should one of these upgraded packages not be to your
3093 liking, remember you can always roll back!
3095 You can display the exact revision of Guix you're currently using by
3102 The information it displays is @emph{all it takes to reproduce the exact
3103 same Guix}, be it at a different point in time or on a different
3106 @quotation Going further
3107 @xref{Invoking guix pull}, for more information. @xref{Channels}, on
3108 how to specify additional @dfn{channels} to pull packages from, how to
3109 replicate Guix, and more. You may also find @command{time-machine}
3110 handy (@pxref{Invoking guix time-machine}).
3113 If you installed Guix System, one of the first things you'll want to do
3114 is to upgrade your system. Once you've run @command{guix pull} to get
3115 the latest Guix, you can upgrade the system like this:
3118 sudo guix system reconfigure /etc/config.scm
3121 Upon completion, the system runs the latest versions of its software
3122 packages. When you eventually reboot, you'll notice a sub-menu in the
3123 bootloader that reads ``Old system generations'': it's what allows you
3124 to boot @emph{an older generation of your system}, should the latest
3125 generation be ``broken'' or otherwise unsatisfying. Just like for
3126 packages, you can always @emph{roll back} to a previous generation
3127 @emph{of the whole system}:
3130 sudo guix system roll-back
3133 There are many things you'll probably want to tweak on your system:
3134 adding new user accounts, adding new system services, fiddling with the
3135 configuration of those services, etc. The system configuration is
3136 @emph{entirely} described in the @file{/etc/config.scm} file.
3137 @xref{Using the Configuration System}, to learn how to change it.
3139 Now you know enough to get started!
3141 @quotation Resources
3142 The rest of this manual provides a reference for all things Guix. Here
3143 are some additional resources you may find useful:
3147 @xref{Top,,, guix-cookbook, The GNU Guix Cookbook}, for a list of
3148 ``how-to'' style of recipes for a variety of applications.
3151 The @uref{https://guix.gnu.org/guix-refcard.pdf, GNU Guix Reference
3152 Card} lists in two pages most of the commands and options you'll ever
3156 The web site contains @uref{https://guix.gnu.org/en/videos/,
3157 instructional videos} covering topics such as everyday use of Guix, how
3158 to get help, and how to become a contributor.
3161 @xref{Documentation}, to learn how to access documentation on your
3165 We hope you will enjoy Guix as much as the community enjoys building it!
3168 @c *********************************************************************
3169 @node Package Management
3170 @chapter Package Management
3173 The purpose of GNU Guix is to allow users to easily install, upgrade, and
3174 remove software packages, without having to know about their build
3175 procedures or dependencies. Guix also goes beyond this obvious set of
3178 This chapter describes the main features of Guix, as well as the
3179 package management tools it provides. Along with the command-line
3180 interface described below (@pxref{Invoking guix package, @code{guix
3181 package}}), you may also use the Emacs-Guix interface (@pxref{Top,,,
3182 emacs-guix, The Emacs-Guix Reference Manual}), after installing
3183 @code{emacs-guix} package (run @kbd{M-x guix-help} command to start
3187 guix install emacs-guix
3191 * Features:: How Guix will make your life brighter.
3192 * Invoking guix package:: Package installation, removal, etc.
3193 * Substitutes:: Downloading pre-built binaries.
3194 * Packages with Multiple Outputs:: Single source package, multiple outputs.
3195 * Invoking guix gc:: Running the garbage collector.
3196 * Invoking guix pull:: Fetching the latest Guix and distribution.
3197 * Invoking guix time-machine:: Running an older revision of Guix.
3198 * Inferiors:: Interacting with another revision of Guix.
3199 * Invoking guix describe:: Display information about your Guix revision.
3200 * Invoking guix archive:: Exporting and importing store files.
3206 Here we assume you've already made your first steps with Guix
3207 (@pxref{Getting Started}) and would like to get an overview about what's
3208 going on under the hood.
3210 When using Guix, each package ends up in the @dfn{package store}, in its
3211 own directory---something that resembles
3212 @file{/gnu/store/xxx-package-1.2}, where @code{xxx} is a base32 string.
3214 Instead of referring to these directories, users have their own
3215 @dfn{profile}, which points to the packages that they actually want to
3216 use. These profiles are stored within each user's home directory, at
3217 @code{$HOME/.guix-profile}.
3219 For example, @code{alice} installs GCC 4.7.2. As a result,
3220 @file{/home/alice/.guix-profile/bin/gcc} points to
3221 @file{/gnu/store/@dots{}-gcc-4.7.2/bin/gcc}. Now, on the same machine,
3222 @code{bob} had already installed GCC 4.8.0. The profile of @code{bob}
3223 simply continues to point to
3224 @file{/gnu/store/@dots{}-gcc-4.8.0/bin/gcc}---i.e., both versions of GCC
3225 coexist on the same system without any interference.
3227 The @command{guix package} command is the central tool to manage
3228 packages (@pxref{Invoking guix package}). It operates on the per-user
3229 profiles, and can be used @emph{with normal user privileges}.
3231 @cindex transactions
3232 The command provides the obvious install, remove, and upgrade
3233 operations. Each invocation is actually a @emph{transaction}: either
3234 the specified operation succeeds, or nothing happens. Thus, if the
3235 @command{guix package} process is terminated during the transaction,
3236 or if a power outage occurs during the transaction, then the user's
3237 profile remains in its previous state, and remains usable.
3239 In addition, any package transaction may be @emph{rolled back}. So, if,
3240 for example, an upgrade installs a new version of a package that turns
3241 out to have a serious bug, users may roll back to the previous instance
3242 of their profile, which was known to work well. Similarly, the global
3243 system configuration on Guix is subject to
3244 transactional upgrades and roll-back
3245 (@pxref{Using the Configuration System}).
3247 All packages in the package store may be @emph{garbage-collected}.
3248 Guix can determine which packages are still referenced by user
3249 profiles, and remove those that are provably no longer referenced
3250 (@pxref{Invoking guix gc}). Users may also explicitly remove old
3251 generations of their profile so that the packages they refer to can be
3254 @cindex reproducibility
3255 @cindex reproducible builds
3256 Guix takes a @dfn{purely functional} approach to package
3257 management, as described in the introduction (@pxref{Introduction}).
3258 Each @file{/gnu/store} package directory name contains a hash of all the
3259 inputs that were used to build that package---compiler, libraries, build
3260 scripts, etc. This direct correspondence allows users to make sure a
3261 given package installation matches the current state of their
3262 distribution. It also helps maximize @dfn{build reproducibility}:
3263 thanks to the isolated build environments that are used, a given build
3264 is likely to yield bit-identical files when performed on different
3265 machines (@pxref{Invoking guix-daemon, container}).
3268 This foundation allows Guix to support @dfn{transparent binary/source
3269 deployment}. When a pre-built binary for a @file{/gnu/store} item is
3270 available from an external source---a @dfn{substitute}, Guix just
3271 downloads it and unpacks it;
3272 otherwise, it builds the package from source, locally
3273 (@pxref{Substitutes}). Because build results are usually bit-for-bit
3274 reproducible, users do not have to trust servers that provide
3275 substitutes: they can force a local build and @emph{challenge} providers
3276 (@pxref{Invoking guix challenge}).
3278 Control over the build environment is a feature that is also useful for
3279 developers. The @command{guix shell} command allows developers of
3280 a package to quickly set up the right development environment for their
3281 package, without having to manually install the dependencies of the
3282 package into their profile (@pxref{Invoking guix shell}).
3284 @cindex replication, of software environments
3285 @cindex provenance tracking, of software artifacts
3286 All of Guix and its package definitions is version-controlled, and
3287 @command{guix pull} allows you to ``travel in time'' on the history of Guix
3288 itself (@pxref{Invoking guix pull}). This makes it possible to replicate a
3289 Guix instance on a different machine or at a later point in time, which in
3290 turn allows you to @emph{replicate complete software environments}, while
3291 retaining precise @dfn{provenance tracking} of the software.
3293 @node Invoking guix package
3294 @section Invoking @command{guix package}
3296 @cindex installing packages
3297 @cindex removing packages
3298 @cindex package installation
3299 @cindex package removal
3301 The @command{guix package} command is the tool that allows users to
3302 install, upgrade, and remove packages, as well as rolling back to
3303 previous configurations. These operations work on a user
3304 @dfn{profile}---a directory of installed packages. Each user has a
3305 default profile in @file{$HOME/.guix-profile}.
3306 The command operates only on the user's own profile,
3307 and works with normal user privileges (@pxref{Features}). Its syntax
3311 guix package @var{options}
3314 @cindex transactions
3315 Primarily, @var{options} specifies the operations to be performed during
3316 the transaction. Upon completion, a new profile is created, but
3317 previous @dfn{generations} of the profile remain available, should the user
3320 For example, to remove @code{lua} and install @code{guile} and
3321 @code{guile-cairo} in a single transaction:
3324 guix package -r lua -i guile guile-cairo
3327 @cindex aliases, for @command{guix package}
3328 For your convenience, we also provide the following aliases:
3332 @command{guix search} is an alias for @command{guix package -s},
3334 @command{guix install} is an alias for @command{guix package -i},
3336 @command{guix remove} is an alias for @command{guix package -r},
3338 @command{guix upgrade} is an alias for @command{guix package -u},
3340 and @command{guix show} is an alias for @command{guix package --show=}.
3343 These aliases are less expressive than @command{guix package} and provide
3344 fewer options, so in some cases you'll probably want to use @command{guix
3347 @command{guix package} also supports a @dfn{declarative approach}
3348 whereby the user specifies the exact set of packages to be available and
3349 passes it @i{via} the @option{--manifest} option
3350 (@pxref{profile-manifest, @option{--manifest}}).
3353 For each user, a symlink to the user's default profile is automatically
3354 created in @file{$HOME/.guix-profile}. This symlink always points to the
3355 current generation of the user's default profile. Thus, users can add
3356 @file{$HOME/.guix-profile/bin} to their @env{PATH} environment
3357 variable, and so on.
3358 @cindex search paths
3359 If you are not using Guix System, consider adding the
3360 following lines to your @file{~/.bash_profile} (@pxref{Bash Startup
3361 Files,,, bash, The GNU Bash Reference Manual}) so that newly-spawned
3362 shells get all the right environment variable definitions:
3365 GUIX_PROFILE="$HOME/.guix-profile" ; \
3366 source "$GUIX_PROFILE/etc/profile"
3369 In a multi-user setup, user profiles are stored in a place registered as
3370 a @dfn{garbage-collector root}, which @file{$HOME/.guix-profile} points
3371 to (@pxref{Invoking guix gc}). That directory is normally
3372 @code{@var{localstatedir}/guix/profiles/per-user/@var{user}}, where
3373 @var{localstatedir} is the value passed to @code{configure} as
3374 @option{--localstatedir}, and @var{user} is the user name. The
3375 @file{per-user} directory is created when @command{guix-daemon} is
3376 started, and the @var{user} sub-directory is created by @command{guix
3379 The @var{options} can be among the following:
3383 @item --install=@var{package} @dots{}
3384 @itemx -i @var{package} @dots{}
3385 Install the specified @var{package}s.
3387 Each @var{package} may specify either a simple package name, such as
3388 @code{guile}, or a package name followed by an at-sign and version number,
3389 such as @code{guile@@1.8.8} or simply @code{guile@@1.8} (in the latter
3390 case, the newest version prefixed by @code{1.8} is selected).
3392 If no version number is specified, the
3393 newest available version will be selected. In addition, @var{package}
3394 may contain a colon, followed by the name of one of the outputs of the
3395 package, as in @code{gcc:doc} or @code{binutils@@2.22:lib}
3396 (@pxref{Packages with Multiple Outputs}). Packages with a corresponding
3397 name (and optionally version) are searched for among the GNU
3398 distribution modules (@pxref{Package Modules}).
3400 @cindex propagated inputs
3401 Sometimes packages have @dfn{propagated inputs}: these are dependencies
3402 that automatically get installed along with the required package
3403 (@pxref{package-propagated-inputs, @code{propagated-inputs} in
3404 @code{package} objects}, for information about propagated inputs in
3405 package definitions).
3407 @anchor{package-cmd-propagated-inputs}
3408 An example is the GNU MPC library: its C header files refer to those of
3409 the GNU MPFR library, which in turn refer to those of the GMP library.
3410 Thus, when installing MPC, the MPFR and GMP libraries also get installed
3411 in the profile; removing MPC also removes MPFR and GMP---unless they had
3412 also been explicitly installed by the user.
3414 Besides, packages sometimes rely on the definition of environment
3415 variables for their search paths (see explanation of
3416 @option{--search-paths} below). Any missing or possibly incorrect
3417 environment variable definitions are reported here.
3419 @item --install-from-expression=@var{exp}
3421 Install the package @var{exp} evaluates to.
3423 @var{exp} must be a Scheme expression that evaluates to a
3424 @code{<package>} object. This option is notably useful to disambiguate
3425 between same-named variants of a package, with expressions such as
3426 @code{(@@ (gnu packages base) guile-final)}.
3428 Note that this option installs the first output of the specified
3429 package, which may be insufficient when needing a specific output of a
3430 multiple-output package.
3432 @item --install-from-file=@var{file}
3433 @itemx -f @var{file}
3434 Install the package that the code within @var{file} evaluates to.
3436 As an example, @var{file} might contain a definition like this
3437 (@pxref{Defining Packages}):
3440 @include package-hello.scm
3443 Developers may find it useful to include such a @file{guix.scm} file
3444 in the root of their project source tree that can be used to test
3445 development snapshots and create reproducible development environments
3446 (@pxref{Invoking guix shell}).
3448 The @var{file} may also contain a JSON representation of one or more
3449 package definitions. Running @code{guix package -f} on
3450 @file{hello.json} with the following contents would result in installing
3451 the package @code{greeter} after building @code{myhello}:
3454 @verbatiminclude package-hello.json
3457 @item --remove=@var{package} @dots{}
3458 @itemx -r @var{package} @dots{}
3459 Remove the specified @var{package}s.
3461 As for @option{--install}, each @var{package} may specify a version number
3462 and/or output name in addition to the package name. For instance,
3463 @samp{-r glibc:debug} would remove the @code{debug} output of
3466 @item --upgrade[=@var{regexp} @dots{}]
3467 @itemx -u [@var{regexp} @dots{}]
3468 @cindex upgrading packages
3469 Upgrade all the installed packages. If one or more @var{regexp}s are
3470 specified, upgrade only installed packages whose name matches a
3471 @var{regexp}. Also see the @option{--do-not-upgrade} option below.
3473 Note that this upgrades package to the latest version of packages found
3474 in the distribution currently installed. To update your distribution,
3475 you should regularly run @command{guix pull} (@pxref{Invoking guix
3478 @cindex package transformations, upgrades
3479 When upgrading, package transformations that were originally applied
3480 when creating the profile are automatically re-applied (@pxref{Package
3481 Transformation Options}). For example, assume you first installed Emacs
3482 from the tip of its development branch with:
3485 guix install emacs-next --with-branch=emacs-next=master
3488 Next time you run @command{guix upgrade}, Guix will again pull the tip
3489 of the Emacs development branch and build @code{emacs-next} from that
3492 Note that transformation options such as @option{--with-branch} and
3493 @option{--with-source} depend on external state; it is up to you to
3494 ensure that they work as expected. You can also discard a
3495 transformations that apply to a package by running:
3498 guix install @var{package}
3501 @item --do-not-upgrade[=@var{regexp} @dots{}]
3502 When used together with the @option{--upgrade} option, do @emph{not}
3503 upgrade any packages whose name matches a @var{regexp}. For example, to
3504 upgrade all packages in the current profile except those containing the
3505 substring ``emacs'':
3508 $ guix package --upgrade . --do-not-upgrade emacs
3511 @item @anchor{profile-manifest}--manifest=@var{file}
3512 @itemx -m @var{file}
3513 @cindex profile declaration
3514 @cindex profile manifest
3515 Create a new generation of the profile from the manifest object
3516 returned by the Scheme code in @var{file}. This option can be repeated
3517 several times, in which case the manifests are concatenated.
3519 This allows you to @emph{declare} the profile's contents rather than
3520 constructing it through a sequence of @option{--install} and similar
3521 commands. The advantage is that @var{file} can be put under version
3522 control, copied to different machines to reproduce the same profile, and
3525 @var{file} must return a @dfn{manifest} object, which is roughly a list
3528 @findex packages->manifest
3530 (use-package-modules guile emacs)
3535 ;; Use a specific package output.
3536 (list guile-2.0 "debug")))
3539 @xref{Writing Manifests}, for information on how to write a manifest.
3540 @xref{export-manifest, @option{--export-manifest}}, to learn how to
3541 obtain a manifest file from an existing profile.
3544 @cindex rolling back
3545 @cindex undoing transactions
3546 @cindex transactions, undoing
3547 Roll back to the previous @dfn{generation} of the profile---i.e., undo
3548 the last transaction.
3550 When combined with options such as @option{--install}, roll back occurs
3551 before any other actions.
3553 When rolling back from the first generation that actually contains
3554 installed packages, the profile is made to point to the @dfn{zeroth
3555 generation}, which contains no files apart from its own metadata.
3557 After having rolled back, installing, removing, or upgrading packages
3558 overwrites previous future generations. Thus, the history of the
3559 generations in a profile is always linear.
3561 @item --switch-generation=@var{pattern}
3562 @itemx -S @var{pattern}
3564 Switch to a particular generation defined by @var{pattern}.
3566 @var{pattern} may be either a generation number or a number prefixed
3567 with ``+'' or ``-''. The latter means: move forward/backward by a
3568 specified number of generations. For example, if you want to return to
3569 the latest generation after @option{--roll-back}, use
3570 @option{--switch-generation=+1}.
3572 The difference between @option{--roll-back} and
3573 @option{--switch-generation=-1} is that @option{--switch-generation} will
3574 not make a zeroth generation, so if a specified generation does not
3575 exist, the current generation will not be changed.
3577 @item --search-paths[=@var{kind}]
3578 @cindex search paths
3579 Report environment variable definitions, in Bash syntax, that may be
3580 needed in order to use the set of installed packages. These environment
3581 variables are used to specify @dfn{search paths} for files used by some
3582 of the installed packages.
3584 For example, GCC needs the @env{CPATH} and @env{LIBRARY_PATH}
3585 environment variables to be defined so it can look for headers and
3586 libraries in the user's profile (@pxref{Environment Variables,,, gcc,
3587 Using the GNU Compiler Collection (GCC)}). If GCC and, say, the C
3588 library are installed in the profile, then @option{--search-paths} will
3589 suggest setting these variables to @file{@var{profile}/include} and
3590 @file{@var{profile}/lib}, respectively (@pxref{Search Paths}, for info
3591 on search path specifications associated with packages.)
3593 The typical use case is to define these environment variables in the
3597 $ eval $(guix package --search-paths)
3600 @var{kind} may be one of @code{exact}, @code{prefix}, or @code{suffix},
3601 meaning that the returned environment variable definitions will either
3602 be exact settings, or prefixes or suffixes of the current value of these
3603 variables. When omitted, @var{kind} defaults to @code{exact}.
3605 This option can also be used to compute the @emph{combined} search paths
3606 of several profiles. Consider this example:
3609 $ guix package -p foo -i guile
3610 $ guix package -p bar -i guile-json
3611 $ guix package -p foo -p bar --search-paths
3614 The last command above reports about the @env{GUILE_LOAD_PATH}
3615 variable, even though, taken individually, neither @file{foo} nor
3616 @file{bar} would lead to that recommendation.
3619 @cindex profile, choosing
3620 @item --profile=@var{profile}
3621 @itemx -p @var{profile}
3622 Use @var{profile} instead of the user's default profile.
3624 @var{profile} must be the name of a file that will be created upon
3625 completion. Concretely, @var{profile} will be a mere symbolic link
3626 (``symlink'') pointing to the actual profile where packages are
3630 $ guix install hello -p ~/code/my-profile
3632 $ ~/code/my-profile/bin/hello
3636 All it takes to get rid of the profile is to remove this symlink and its
3637 siblings that point to specific generations:
3640 $ rm ~/code/my-profile ~/code/my-profile-*-link
3643 @item --list-profiles
3644 List all the user's profiles:
3647 $ guix package --list-profiles
3648 /home/charlie/.guix-profile
3649 /home/charlie/code/my-profile
3650 /home/charlie/code/devel-profile
3651 /home/charlie/tmp/test
3654 When running as root, list all the profiles of all the users.
3656 @cindex collisions, in a profile
3657 @cindex colliding packages in profiles
3658 @cindex profile collisions
3659 @item --allow-collisions
3660 Allow colliding packages in the new profile. Use at your own risk!
3662 By default, @command{guix package} reports as an error @dfn{collisions}
3663 in the profile. Collisions happen when two or more different versions
3664 or variants of a given package end up in the profile.
3667 Use the bootstrap Guile to build the profile. This option is only
3668 useful to distribution developers.
3672 In addition to these actions, @command{guix package} supports the
3673 following options to query the current state of a profile, or the
3674 availability of packages:
3678 @item --search=@var{regexp}
3679 @itemx -s @var{regexp}
3680 @anchor{guix-search}
3681 @cindex searching for packages
3682 List the available packages whose name, synopsis, or description matches
3683 @var{regexp} (in a case-insensitive fashion), sorted by relevance.
3684 Print all the metadata of matching packages in
3685 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils,
3686 GNU recutils manual}).
3688 This allows specific fields to be extracted using the @command{recsel}
3689 command, for instance:
3692 $ guix package -s malloc | recsel -p name,version,relevance
3706 Similarly, to show the name of all the packages available under the
3707 terms of the GNU@tie{}LGPL version 3:
3710 $ guix package -s "" | recsel -p name -e 'license ~ "LGPL 3"'
3717 It is also possible to refine search results using several @code{-s} flags to
3718 @command{guix package}, or several arguments to @command{guix search}. For
3719 example, the following command returns a list of board games (this time using
3720 the @command{guix search} alias):
3723 $ guix search '\<board\>' game | recsel -p name
3728 If we were to omit @code{-s game}, we would also get software packages
3729 that deal with printed circuit boards; removing the angle brackets
3730 around @code{board} would further add packages that have to do with
3733 And now for a more elaborate example. The following command searches
3734 for cryptographic libraries, filters out Haskell, Perl, Python, and Ruby
3735 libraries, and prints the name and synopsis of the matching packages:
3738 $ guix search crypto library | \
3739 recsel -e '! (name ~ "^(ghc|perl|python|ruby)")' -p name,synopsis
3743 @xref{Selection Expressions,,, recutils, GNU recutils manual}, for more
3744 information on @dfn{selection expressions} for @code{recsel -e}.
3746 @item --show=@var{package}
3747 Show details about @var{package}, taken from the list of available packages, in
3748 @code{recutils} format (@pxref{Top, GNU recutils databases,, recutils, GNU
3752 $ guix package --show=guile | recsel -p name,version
3764 You may also specify the full name of a package to only get details about a
3765 specific version of it (this time using the @command{guix show} alias):
3767 $ guix show guile@@3.0.5 | recsel -p name,version
3772 @item --list-installed[=@var{regexp}]
3773 @itemx -I [@var{regexp}]
3774 List the currently installed packages in the specified profile, with the
3775 most recently installed packages shown last. When @var{regexp} is
3776 specified, list only installed packages whose name matches @var{regexp}.
3778 For each installed package, print the following items, separated by
3779 tabs: the package name, its version string, the part of the package that
3780 is installed (for instance, @code{out} for the default output,
3781 @code{include} for its headers, etc.), and the path of this package in
3784 @item --list-available[=@var{regexp}]
3785 @itemx -A [@var{regexp}]
3786 List packages currently available in the distribution for this system
3787 (@pxref{GNU Distribution}). When @var{regexp} is specified, list only
3788 available packages whose name matches @var{regexp}.
3790 For each package, print the following items separated by tabs: its name,
3791 its version string, the parts of the package (@pxref{Packages with
3792 Multiple Outputs}), and the source location of its definition.
3794 @item --list-generations[=@var{pattern}]
3795 @itemx -l [@var{pattern}]
3797 Return a list of generations along with their creation dates; for each
3798 generation, show the installed packages, with the most recently
3799 installed packages shown last. Note that the zeroth generation is never
3802 For each installed package, print the following items, separated by
3803 tabs: the name of a package, its version string, the part of the package
3804 that is installed (@pxref{Packages with Multiple Outputs}), and the
3805 location of this package in the store.
3807 When @var{pattern} is used, the command returns only matching
3808 generations. Valid patterns include:
3811 @item @emph{Integers and comma-separated integers}. Both patterns denote
3812 generation numbers. For instance, @option{--list-generations=1} returns
3815 And @option{--list-generations=1,8,2} outputs three generations in the
3816 specified order. Neither spaces nor trailing commas are allowed.
3818 @item @emph{Ranges}. @option{--list-generations=2..9} prints the
3819 specified generations and everything in between. Note that the start of
3820 a range must be smaller than its end.
3822 It is also possible to omit the endpoint. For example,
3823 @option{--list-generations=2..}, returns all generations starting from the
3826 @item @emph{Durations}. You can also get the last @emph{N}@tie{}days, weeks,
3827 or months by passing an integer along with the first letter of the
3828 duration. For example, @option{--list-generations=20d} lists generations
3829 that are up to 20 days old.
3832 @item --delete-generations[=@var{pattern}]
3833 @itemx -d [@var{pattern}]
3834 When @var{pattern} is omitted, delete all generations except the current
3837 This command accepts the same patterns as @option{--list-generations}.
3838 When @var{pattern} is specified, delete the matching generations. When
3839 @var{pattern} specifies a duration, generations @emph{older} than the
3840 specified duration match. For instance, @option{--delete-generations=1m}
3841 deletes generations that are more than one month old.
3843 If the current generation matches, it is @emph{not} deleted. Also, the
3844 zeroth generation is never deleted.
3846 Note that deleting generations prevents rolling back to them.
3847 Consequently, this command must be used with care.
3849 @cindex manifest, exporting
3850 @anchor{export-manifest}
3851 @item --export-manifest
3852 Write to standard output a manifest suitable for @option{--manifest}
3853 corresponding to the chosen profile(s).
3855 This option is meant to help you migrate from the ``imperative''
3856 operating mode---running @command{guix install}, @command{guix upgrade},
3857 etc.---to the declarative mode that @option{--manifest} offers.
3859 Be aware that the resulting manifest @emph{approximates} what your
3860 profile actually contains; for instance, depending on how your profile
3861 was created, it can refer to packages or package versions that are not
3862 exactly what you specified.
3864 Keep in mind that a manifest is purely symbolic: it only contains
3865 package names and possibly versions, and their meaning varies over time.
3866 If you wish to ``pin'' channels to the revisions that were used to build
3867 the profile(s), see @option{--export-channels} below.
3869 @cindex pinning, channel revisions of a profile
3870 @item --export-channels
3871 Write to standard output the list of channels used by the chosen
3872 profile(s), in a format suitable for @command{guix pull --channels} or
3873 @command{guix time-machine --channels} (@pxref{Channels}).
3875 Together with @option{--export-manifest}, this option provides
3876 information allowing you to replicate the current profile
3877 (@pxref{Replicating Guix}).
3879 However, note that the output of this command @emph{approximates} what
3880 was actually used to build this profile. In particular, a single
3881 profile might have been built from several different revisions of the
3882 same channel. In that case, @option{--export-manifest} chooses the last
3883 one and writes the list of other revisions in a comment. If you really
3884 need to pick packages from different channel revisions, you can use
3885 inferiors in your manifest to do so (@pxref{Inferiors}).
3887 Together with @option{--export-manifest}, this is a good starting point
3888 if you are willing to migrate from the ``imperative'' model to the fully
3889 declarative model consisting of a manifest file along with a channels
3890 file pinning the exact channel revision(s) you want.
3893 Finally, since @command{guix package} may actually start build
3894 processes, it supports all the common build options (@pxref{Common Build
3895 Options}). It also supports package transformation options, such as
3896 @option{--with-source}, and preserves them across upgrades
3897 (@pxref{Package Transformation Options}).
3900 @section Substitutes
3903 @cindex pre-built binaries
3904 Guix supports transparent source/binary deployment, which means that it
3905 can either build things locally, or download pre-built items from a
3906 server, or both. We call these pre-built items @dfn{substitutes}---they
3907 are substitutes for local build results. In many cases, downloading a
3908 substitute is much faster than building things locally.
3910 Substitutes can be anything resulting from a derivation build
3911 (@pxref{Derivations}). Of course, in the common case, they are
3912 pre-built package binaries, but source tarballs, for instance, which
3913 also result from derivation builds, can be available as substitutes.
3916 * Official Substitute Servers:: One particular source of substitutes.
3917 * Substitute Server Authorization:: How to enable or disable substitutes.
3918 * Getting Substitutes from Other Servers:: Substitute diversity.
3919 * Substitute Authentication:: How Guix verifies substitutes.
3920 * Proxy Settings:: How to get substitutes via proxy.
3921 * Substitution Failure:: What happens when substitution fails.
3922 * On Trusting Binaries:: How can you trust that binary blob?
3925 @node Official Substitute Servers
3926 @subsection Official Substitute Servers
3929 @code{@value{SUBSTITUTE-SERVER-1}} and
3930 @code{@value{SUBSTITUTE-SERVER-2}} are both front-ends to official build
3931 farms that build packages from Guix continuously for some architectures,
3932 and make them available as substitutes. These are the default source of
3933 substitutes; which can be overridden by passing the
3934 @option{--substitute-urls} option either to @command{guix-daemon}
3935 (@pxref{daemon-substitute-urls,, @code{guix-daemon --substitute-urls}})
3936 or to client tools such as @command{guix package}
3937 (@pxref{client-substitute-urls,, client @option{--substitute-urls}
3940 Substitute URLs can be either HTTP or HTTPS.
3941 HTTPS is recommended because communications are encrypted; conversely,
3942 using HTTP makes all communications visible to an eavesdropper, who
3943 could use the information gathered to determine, for instance, whether
3944 your system has unpatched security vulnerabilities.
3946 Substitutes from the official build farms are enabled by default when
3947 using Guix System (@pxref{GNU Distribution}). However,
3948 they are disabled by default when using Guix on a foreign distribution,
3949 unless you have explicitly enabled them via one of the recommended
3950 installation steps (@pxref{Installation}). The following paragraphs
3951 describe how to enable or disable substitutes for the official build
3952 farm; the same procedure can also be used to enable substitutes for any
3953 other substitute server.
3955 @node Substitute Server Authorization
3956 @subsection Substitute Server Authorization
3959 @cindex substitutes, authorization thereof
3960 @cindex access control list (ACL), for substitutes
3961 @cindex ACL (access control list), for substitutes
3962 To allow Guix to download substitutes from @code{@value{SUBSTITUTE-SERVER-1}}, @code{@value{SUBSTITUTE-SERVER-2}} or a mirror, you
3963 must add the relevant public key to the access control list (ACL) of archive
3964 imports, using the @command{guix archive} command (@pxref{Invoking guix
3965 archive}). Doing so implies that you trust the substitute server to not
3966 be compromised and to serve genuine substitutes.
3969 If you are using Guix System, you can skip this section: Guix System
3970 authorizes substitutes from @code{@value{SUBSTITUTE-SERVER-1}} and
3971 @code{@value{SUBSTITUTE-SERVER-2}} by default.
3974 The public keys for each of the project maintained substitute servers
3975 are installed along with Guix, in @code{@var{prefix}/share/guix/}, where
3976 @var{prefix} is the installation prefix of Guix. If you installed Guix
3977 from source, make sure you checked the GPG signature of
3978 @file{guix-@value{VERSION}.tar.gz}, which contains this public key file.
3979 Then, you can run something like this:
3982 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-1}.pub
3983 # guix archive --authorize < @var{prefix}/share/guix/@value{SUBSTITUTE-SERVER-2}.pub
3986 Once this is in place, the output of a command like @code{guix build}
3987 should change from something like:
3990 $ guix build emacs --dry-run
3991 The following derivations would be built:
3992 /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv
3993 /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv
3994 /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-1.0.27.1.tar.bz2.drv
3995 /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv
4003 $ guix build emacs --dry-run
4004 112.3 MB would be downloaded:
4005 /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3
4006 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d
4007 /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16
4008 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7
4013 The text changed from ``The following derivations would be built'' to
4014 ``112.3 MB would be downloaded''. This indicates that substitutes from
4015 the configured substitute servers are usable and will be downloaded,
4016 when possible, for future builds.
4018 @cindex substitutes, how to disable
4019 The substitute mechanism can be disabled globally by running
4020 @code{guix-daemon} with @option{--no-substitutes} (@pxref{Invoking
4021 guix-daemon}). It can also be disabled temporarily by passing the
4022 @option{--no-substitutes} option to @command{guix package},
4023 @command{guix build}, and other command-line tools.
4025 @node Getting Substitutes from Other Servers
4026 @subsection Getting Substitutes from Other Servers
4028 @cindex substitute servers, adding more
4029 Guix can look up and fetch substitutes from several servers. This is
4030 useful when you are using packages from additional channels for which
4031 the official server does not have substitutes but another server
4032 provides them. Another situation where this is useful is when you would
4033 prefer to download from your organization's substitute server, resorting
4034 to the official server only as a fallback or dismissing it altogether.
4036 You can give Guix a list of substitute server URLs and it will check
4037 them in the specified order. You also need to explicitly authorize the
4038 public keys of substitute servers to instruct Guix to accept the
4039 substitutes they sign.
4041 On Guix System, this is achieved by modifying the configuration of the
4042 @code{guix} service. Since the @code{guix} service is part of the
4043 default lists of services, @code{%base-services} and
4044 @code{%desktop-services}, you can use @code{modify-services} to change
4045 its configuration and add the URLs and substitute keys that you want
4046 (@pxref{Service Reference, @code{modify-services}}).
4048 As an example, suppose you want to fetch substitutes from
4049 @code{guix.example.org} and to authorize the signing key of that server,
4050 in addition to the default @code{@value{SUBSTITUTE-SERVER-1}} and
4051 @code{@value{SUBSTITUTE-SERVER-2}}. The resulting operating system
4052 configuration will look something like:
4058 ;; Assume we're starting from '%desktop-services'. Replace it
4059 ;; with the list of services you're actually using.
4060 (modify-services %desktop-services
4061 (guix-service-type config =>
4065 (append (list "https://guix.example.org")
4066 %default-substitute-urls))
4068 (append (list (local-file "./key.pub"))
4069 %default-authorized-guix-keys)))))))
4072 This assumes that the file @file{key.pub} contains the signing key of
4073 @code{guix.example.org}. With this change in place in your operating
4074 system configuration file (say @file{/etc/config.scm}), you can
4075 reconfigure and restart the @code{guix-daemon} service or reboot so the
4076 changes take effect:
4079 $ sudo guix system reconfigure /etc/config.scm
4080 $ sudo herd restart guix-daemon
4083 If you're running Guix on a ``foreign distro'', you would instead take
4084 the following steps to get substitutes from additional servers:
4088 Edit the service configuration file for @code{guix-daemon}; when using
4089 systemd, this is normally
4090 @file{/etc/systemd/system/guix-daemon.service}. Add the
4091 @option{--substitute-urls} option on the @command{guix-daemon} command
4092 line and list the URLs of interest (@pxref{daemon-substitute-urls,
4093 @code{guix-daemon --substitute-urls}}):
4096 @dots{} --substitute-urls='https://guix.example.org @value{SUBSTITUTE-URLS}'
4100 Restart the daemon. For systemd, it goes like this:
4103 systemctl daemon-reload
4104 systemctl restart guix-daemon.service
4108 Authorize the key of the new server (@pxref{Invoking guix archive}):
4111 guix archive --authorize < key.pub
4114 Again this assumes @file{key.pub} contains the public key that
4115 @code{guix.example.org} uses to sign substitutes.
4118 Now you're all set! Substitutes will be preferably taken from
4119 @code{https://guix.example.org}, using
4120 @code{@value{SUBSTITUTE-SERVER-1}} then
4121 @code{@value{SUBSTITUTE-SERVER-2}} as fallback options. Of course you
4122 can list as many substitute servers as you like, with the caveat that
4123 substitute lookup can be slowed down if too many servers need to be
4126 Note that there are also situations where one may want to add the URL of
4127 a substitute server @emph{without} authorizing its key.
4128 @xref{Substitute Authentication}, to understand this fine point.
4130 @node Substitute Authentication
4131 @subsection Substitute Authentication
4133 @cindex digital signatures
4134 Guix detects and raises an error when attempting to use a substitute
4135 that has been tampered with. Likewise, it ignores substitutes that are
4136 not signed, or that are not signed by one of the keys listed in the ACL.
4138 There is one exception though: if an unauthorized server provides
4139 substitutes that are @emph{bit-for-bit identical} to those provided by
4140 an authorized server, then the unauthorized server becomes eligible for
4141 downloads. For example, assume we have chosen two substitute servers
4145 --substitute-urls="https://a.example.org https://b.example.org"
4149 @cindex reproducible builds
4150 If the ACL contains only the key for @samp{b.example.org}, and if
4151 @samp{a.example.org} happens to serve the @emph{exact same} substitutes,
4152 then Guix will download substitutes from @samp{a.example.org} because it
4153 comes first in the list and can be considered a mirror of
4154 @samp{b.example.org}. In practice, independent build machines usually
4155 produce the same binaries, thanks to bit-reproducible builds (see
4158 When using HTTPS, the server's X.509 certificate is @emph{not} validated
4159 (in other words, the server is not authenticated), contrary to what
4160 HTTPS clients such as Web browsers usually do. This is because Guix
4161 authenticates substitute information itself, as explained above, which
4162 is what we care about (whereas X.509 certificates are about
4163 authenticating bindings between domain names and public keys).
4165 @node Proxy Settings
4166 @subsection Proxy Settings
4170 Substitutes are downloaded over HTTP or HTTPS@. The @env{http_proxy} and
4171 @env{https_proxy} environment variables can be set in the environment of
4172 @command{guix-daemon} and are honored for downloads of substitutes.
4173 Note that the value of those environment variables in the environment
4174 where @command{guix build}, @command{guix package}, and other client
4175 commands are run has @emph{absolutely no effect}.
4177 @node Substitution Failure
4178 @subsection Substitution Failure
4180 Even when a substitute for a derivation is available, sometimes the
4181 substitution attempt will fail. This can happen for a variety of
4182 reasons: the substitute server might be offline, the substitute may
4183 recently have been deleted, the connection might have been interrupted,
4186 When substitutes are enabled and a substitute for a derivation is
4187 available, but the substitution attempt fails, Guix will attempt to
4188 build the derivation locally depending on whether or not
4189 @option{--fallback} was given (@pxref{fallback-option,, common build
4190 option @option{--fallback}}). Specifically, if @option{--fallback} was
4191 omitted, then no local build will be performed, and the derivation is
4192 considered to have failed. However, if @option{--fallback} was given,
4193 then Guix will attempt to build the derivation locally, and the success
4194 or failure of the derivation depends on the success or failure of the
4195 local build. Note that when substitutes are disabled or no substitute
4196 is available for the derivation in question, a local build will
4197 @emph{always} be performed, regardless of whether or not
4198 @option{--fallback} was given.
4200 To get an idea of how many substitutes are available right now, you can
4201 try running the @command{guix weather} command (@pxref{Invoking guix
4202 weather}). This command provides statistics on the substitutes provided
4205 @node On Trusting Binaries
4206 @subsection On Trusting Binaries
4208 @cindex trust, of pre-built binaries
4209 Today, each individual's control over their own computing is at the
4210 mercy of institutions, corporations, and groups with enough power and
4211 determination to subvert the computing infrastructure and exploit its
4212 weaknesses. While using substitutes can be convenient, we encourage
4213 users to also build on their own, or even run their own build farm, such
4214 that the project run substitute servers are less of an interesting
4215 target. One way to help is by publishing the software you build using
4216 @command{guix publish} so that others have one more choice of server to
4217 download substitutes from (@pxref{Invoking guix publish}).
4219 Guix has the foundations to maximize build reproducibility
4220 (@pxref{Features}). In most cases, independent builds of a given
4221 package or derivation should yield bit-identical results. Thus, through
4222 a diverse set of independent package builds, we can strengthen the
4223 integrity of our systems. The @command{guix challenge} command aims to
4224 help users assess substitute servers, and to assist developers in
4225 finding out about non-deterministic package builds (@pxref{Invoking guix
4226 challenge}). Similarly, the @option{--check} option of @command{guix
4227 build} allows users to check whether previously-installed substitutes
4228 are genuine by rebuilding them locally (@pxref{build-check,
4229 @command{guix build --check}}).
4231 In the future, we want Guix to have support to publish and retrieve
4232 binaries to/from other users, in a peer-to-peer fashion. If you would
4233 like to discuss this project, join us on @email{guix-devel@@gnu.org}.
4235 @node Packages with Multiple Outputs
4236 @section Packages with Multiple Outputs
4238 @cindex multiple-output packages
4239 @cindex package outputs
4242 Often, packages defined in Guix have a single @dfn{output}---i.e., the
4243 source package leads to exactly one directory in the store. When running
4244 @command{guix install glibc}, one installs the default output of the
4245 GNU libc package; the default output is called @code{out}, but its name
4246 can be omitted as shown in this command. In this particular case, the
4247 default output of @code{glibc} contains all the C header files, shared
4248 libraries, static libraries, Info documentation, and other supporting
4251 Sometimes it is more appropriate to separate the various types of files
4252 produced from a single source package into separate outputs. For
4253 instance, the GLib C library (used by GTK+ and related packages)
4254 installs more than 20 MiB of reference documentation as HTML pages.
4255 To save space for users who do not need it, the documentation goes to a
4256 separate output, called @code{doc}. To install the main GLib output,
4257 which contains everything but the documentation, one would run:
4263 @cindex documentation
4264 The command to install its documentation is:
4267 guix install glib:doc
4270 Some packages install programs with different ``dependency footprints''.
4271 For instance, the WordNet package installs both command-line tools and
4272 graphical user interfaces (GUIs). The former depend solely on the C
4273 library, whereas the latter depend on Tcl/Tk and the underlying X
4274 libraries. In this case, we leave the command-line tools in the default
4275 output, whereas the GUIs are in a separate output. This allows users
4276 who do not need the GUIs to save space. The @command{guix size} command
4277 can help find out about such situations (@pxref{Invoking guix size}).
4278 @command{guix graph} can also be helpful (@pxref{Invoking guix graph}).
4280 There are several such multiple-output packages in the GNU distribution.
4281 Other conventional output names include @code{lib} for libraries and
4282 possibly header files, @code{bin} for stand-alone programs, and
4283 @code{debug} for debugging information (@pxref{Installing Debugging
4284 Files}). The outputs of a packages are listed in the third column of
4285 the output of @command{guix package --list-available} (@pxref{Invoking
4289 @node Invoking guix gc
4290 @section Invoking @command{guix gc}
4292 @cindex garbage collector
4294 Packages that are installed, but not used, may be @dfn{garbage-collected}.
4295 The @command{guix gc} command allows users to explicitly run the garbage
4296 collector to reclaim space from the @file{/gnu/store} directory. It is
4297 the @emph{only} way to remove files from @file{/gnu/store}---removing
4298 files or directories manually may break it beyond repair!
4301 @cindex garbage collector roots
4302 The garbage collector has a set of known @dfn{roots}: any file under
4303 @file{/gnu/store} reachable from a root is considered @dfn{live} and
4304 cannot be deleted; any other file is considered @dfn{dead} and may be
4305 deleted. The set of garbage collector roots (``GC roots'' for short)
4306 includes default user profiles; by default, the symlinks under
4307 @file{/var/guix/gcroots} represent these GC roots. New GC roots can be
4308 added with @command{guix build --root}, for example (@pxref{Invoking
4309 guix build}). The @command{guix gc --list-roots} command lists them.
4311 Prior to running @code{guix gc --collect-garbage} to make space, it is
4312 often useful to remove old generations from user profiles; that way, old
4313 package builds referenced by those generations can be reclaimed. This
4314 is achieved by running @code{guix package --delete-generations}
4315 (@pxref{Invoking guix package}).
4317 Our recommendation is to run a garbage collection periodically, or when
4318 you are short on disk space. For instance, to guarantee that at least
4319 5@tie{}GB are available on your disk, simply run:
4325 It is perfectly safe to run as a non-interactive periodic job
4326 (@pxref{Scheduled Job Execution}, for how to set up such a job).
4327 Running @command{guix gc} with no arguments will collect as
4328 much garbage as it can, but that is often inconvenient: you may find
4329 yourself having to rebuild or re-download software that is ``dead'' from
4330 the GC viewpoint but that is necessary to build other pieces of
4331 software---e.g., the compiler tool chain.
4333 The @command{guix gc} command has three modes of operation: it can be
4334 used to garbage-collect any dead files (the default), to delete specific
4335 files (the @option{--delete} option), to print garbage-collector
4336 information, or for more advanced queries. The garbage collection
4337 options are as follows:
4340 @item --collect-garbage[=@var{min}]
4341 @itemx -C [@var{min}]
4342 Collect garbage---i.e., unreachable @file{/gnu/store} files and
4343 sub-directories. This is the default operation when no option is
4346 When @var{min} is given, stop once @var{min} bytes have been collected.
4347 @var{min} may be a number of bytes, or it may include a unit as a
4348 suffix, such as @code{MiB} for mebibytes and @code{GB} for gigabytes
4349 (@pxref{Block size, size specifications,, coreutils, GNU Coreutils}).
4351 When @var{min} is omitted, collect all the garbage.
4353 @item --free-space=@var{free}
4354 @itemx -F @var{free}
4355 Collect garbage until @var{free} space is available under
4356 @file{/gnu/store}, if possible; @var{free} denotes storage space, such
4357 as @code{500MiB}, as described above.
4359 When @var{free} or more is already available in @file{/gnu/store}, do
4360 nothing and exit immediately.
4362 @item --delete-generations[=@var{duration}]
4363 @itemx -d [@var{duration}]
4364 Before starting the garbage collection process, delete all the generations
4365 older than @var{duration}, for all the user profiles and home environment
4366 generations; when run as root, this
4367 applies to all the profiles @emph{of all the users}.
4369 For example, this command deletes all the generations of all your profiles
4370 that are older than 2 months (except generations that are current), and then
4371 proceeds to free space until at least 10 GiB are available:
4374 guix gc -d 2m -F 10G
4379 Attempt to delete all the store files and directories specified as
4380 arguments. This fails if some of the files are not in the store, or if
4381 they are still live.
4383 @item --list-failures
4384 List store items corresponding to cached build failures.
4386 This prints nothing unless the daemon was started with
4387 @option{--cache-failures} (@pxref{Invoking guix-daemon,
4388 @option{--cache-failures}}).
4391 List the GC roots owned by the user; when run as root, list @emph{all} the GC
4395 List store items in use by currently running processes. These store
4396 items are effectively considered GC roots: they cannot be deleted.
4398 @item --clear-failures
4399 Remove the specified store items from the failed-build cache.
4401 Again, this option only makes sense when the daemon is started with
4402 @option{--cache-failures}. Otherwise, it does nothing.
4405 Show the list of dead files and directories still present in the
4406 store---i.e., files and directories no longer reachable from any root.
4409 Show the list of live store files and directories.
4413 In addition, the references among existing store files can be queried:
4419 @cindex package dependencies
4420 List the references (respectively, the referrers) of store files given
4426 List the requisites of the store files passed as arguments. Requisites
4427 include the store files themselves, their references, and the references
4428 of these, recursively. In other words, the returned list is the
4429 @dfn{transitive closure} of the store files.
4431 @xref{Invoking guix size}, for a tool to profile the size of the closure
4432 of an element. @xref{Invoking guix graph}, for a tool to visualize
4433 the graph of references.
4437 Return the derivation(s) leading to the given store items
4438 (@pxref{Derivations}).
4440 For example, this command:
4443 guix gc --derivers $(guix package -I ^emacs$ | cut -f4)
4447 returns the @file{.drv} file(s) leading to the @code{emacs} package
4448 installed in your profile.
4450 Note that there may be zero matching @file{.drv} files, for instance
4451 because these files have been garbage-collected. There can also be more
4452 than one matching @file{.drv} due to fixed-output derivations.
4455 Lastly, the following options allow you to check the integrity of the
4456 store and to control disk usage.
4460 @item --verify[=@var{options}]
4461 @cindex integrity, of the store
4462 @cindex integrity checking
4463 Verify the integrity of the store.
4465 By default, make sure that all the store items marked as valid in the
4466 database of the daemon actually exist in @file{/gnu/store}.
4468 When provided, @var{options} must be a comma-separated list containing one
4469 or more of @code{contents} and @code{repair}.
4471 When passing @option{--verify=contents}, the daemon computes the
4472 content hash of each store item and compares it against its hash in the
4473 database. Hash mismatches are reported as data corruptions. Because it
4474 traverses @emph{all the files in the store}, this command can take a
4475 long time, especially on systems with a slow disk drive.
4477 @cindex repairing the store
4478 @cindex corruption, recovering from
4479 Using @option{--verify=repair} or @option{--verify=contents,repair}
4480 causes the daemon to try to repair corrupt store items by fetching
4481 substitutes for them (@pxref{Substitutes}). Because repairing is not
4482 atomic, and thus potentially dangerous, it is available only to the
4483 system administrator. A lightweight alternative, when you know exactly
4484 which items in the store are corrupt, is @command{guix build --repair}
4485 (@pxref{Invoking guix build}).
4488 @cindex deduplication
4489 Optimize the store by hard-linking identical files---this is
4490 @dfn{deduplication}.
4492 The daemon performs deduplication after each successful build or archive
4493 import, unless it was started with @option{--disable-deduplication}
4494 (@pxref{Invoking guix-daemon, @option{--disable-deduplication}}). Thus,
4495 this option is primarily useful when the daemon was running with
4496 @option{--disable-deduplication}.
4500 @node Invoking guix pull
4501 @section Invoking @command{guix pull}
4503 @cindex upgrading Guix
4504 @cindex updating Guix
4505 @cindex @command{guix pull}
4507 @cindex security, @command{guix pull}
4508 @cindex authenticity, of code obtained with @command{guix pull}
4509 Packages are installed or upgraded to the latest version available in
4510 the distribution currently available on your local machine. To update
4511 that distribution, along with the Guix tools, you must run @command{guix
4512 pull}: the command downloads the latest Guix source code and package
4513 descriptions, and deploys it. Source code is downloaded from a
4514 @uref{https://git-scm.com, Git} repository, by default the official
4515 GNU@tie{}Guix repository, though this can be customized. @command{guix
4516 pull} ensures that the code it downloads is @emph{authentic} by
4517 verifying that commits are signed by Guix developers.
4519 Specifically, @command{guix pull} downloads code from the @dfn{channels}
4520 (@pxref{Channels}) specified by one of the followings, in this order:
4524 the @option{--channels} option;
4526 the user's @file{~/.config/guix/channels.scm} file;
4528 the system-wide @file{/etc/guix/channels.scm} file;
4530 the built-in default channels specified in the @code{%default-channels}
4534 On completion, @command{guix package} will use packages and package
4535 versions from this just-retrieved copy of Guix. Not only that, but all
4536 the Guix commands and Scheme modules will also be taken from that latest
4537 version. New @command{guix} sub-commands added by the update also
4540 Any user can update their Guix copy using @command{guix pull}, and the
4541 effect is limited to the user who ran @command{guix pull}. For
4542 instance, when user @code{root} runs @command{guix pull}, this has no
4543 effect on the version of Guix that user @code{alice} sees, and vice
4546 The result of running @command{guix pull} is a @dfn{profile} available
4547 under @file{~/.config/guix/current} containing the latest Guix. Thus,
4548 make sure to add it to the beginning of your search path so that you use
4549 the latest version, and similarly for the Info manual
4550 (@pxref{Documentation}):
4553 export PATH="$HOME/.config/guix/current/bin:$PATH"
4554 export INFOPATH="$HOME/.config/guix/current/share/info:$INFOPATH"
4557 The @option{--list-generations} or @option{-l} option lists past generations
4558 produced by @command{guix pull}, along with details about their provenance:
4562 Generation 1 Jun 10 2018 00:18:18
4564 repository URL: https://git.savannah.gnu.org/git/guix.git
4565 branch: origin/master
4566 commit: 65956ad3526ba09e1f7a40722c96c6ef7c0936fe
4568 Generation 2 Jun 11 2018 11:02:49
4570 repository URL: https://git.savannah.gnu.org/git/guix.git
4571 branch: origin/master
4572 commit: e0cc7f669bec22c37481dd03a7941c7d11a64f1d
4574 Generation 3 Jun 13 2018 23:31:07 (current)
4576 repository URL: https://git.savannah.gnu.org/git/guix.git
4577 branch: origin/master
4578 commit: 844cc1c8f394f03b404c5bb3aee086922373490c
4581 @xref{Invoking guix describe, @command{guix describe}}, for other ways to
4582 describe the current status of Guix.
4584 This @code{~/.config/guix/current} profile works exactly like the profiles
4585 created by @command{guix package} (@pxref{Invoking guix package}). That
4586 is, you can list generations, roll back to the previous
4587 generation---i.e., the previous Guix---and so on:
4590 $ guix pull --roll-back
4591 switched from generation 3 to 2
4592 $ guix pull --delete-generations=1
4593 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4596 You can also use @command{guix package} (@pxref{Invoking guix package})
4597 to manage the profile by naming it explicitly:
4599 $ guix package -p ~/.config/guix/current --roll-back
4600 switched from generation 3 to 2
4601 $ guix package -p ~/.config/guix/current --delete-generations=1
4602 deleting /var/guix/profiles/per-user/charlie/current-guix-1-link
4605 The @command{guix pull} command is usually invoked with no arguments,
4606 but it supports the following options:
4609 @item --url=@var{url}
4610 @itemx --commit=@var{commit}
4611 @itemx --branch=@var{branch}
4612 Download code for the @code{guix} channel from the specified @var{url}, at the
4613 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4614 string), or @var{branch}.
4616 @cindex @file{channels.scm}, configuration file
4617 @cindex configuration file for channels
4618 These options are provided for convenience, but you can also specify your
4619 configuration in the @file{~/.config/guix/channels.scm} file or using the
4620 @option{--channels} option (see below).
4622 @item --channels=@var{file}
4623 @itemx -C @var{file}
4624 Read the list of channels from @var{file} instead of
4625 @file{~/.config/guix/channels.scm} or @file{/etc/guix/channels.scm}.
4626 @var{file} must contain Scheme code that
4627 evaluates to a list of channel objects. @xref{Channels}, for more
4630 @cindex channel news
4633 Display news written by channel authors for their users for changes made
4634 since the previous generation (@pxref{Channels, Writing Channel News}).
4635 When @option{--details} is passed, additionally display new and upgraded
4638 You can view that information for previous generations with
4639 @command{guix pull -l}.
4641 @item --list-generations[=@var{pattern}]
4642 @itemx -l [@var{pattern}]
4643 List all the generations of @file{~/.config/guix/current} or, if @var{pattern}
4644 is provided, the subset of generations that match @var{pattern}.
4645 The syntax of @var{pattern} is the same as with @code{guix package
4646 --list-generations} (@pxref{Invoking guix package}).
4648 By default, this prints information about the channels used in each
4649 revision as well as the corresponding news entries. If you pass
4650 @option{--details}, it will also print the list of packages added and
4651 upgraded in each generation compared to the previous one.
4654 Instruct @option{--list-generations} or @option{--news} to display more
4655 information about the differences between subsequent generations---see
4659 @cindex rolling back
4660 @cindex undoing transactions
4661 @cindex transactions, undoing
4662 Roll back to the previous @dfn{generation} of @file{~/.config/guix/current}---i.e.,
4663 undo the last transaction.
4665 @item --switch-generation=@var{pattern}
4666 @itemx -S @var{pattern}
4668 Switch to a particular generation defined by @var{pattern}.
4670 @var{pattern} may be either a generation number or a number prefixed
4671 with ``+'' or ``-''. The latter means: move forward/backward by a
4672 specified number of generations. For example, if you want to return to
4673 the latest generation after @option{--roll-back}, use
4674 @option{--switch-generation=+1}.
4676 @item --delete-generations[=@var{pattern}]
4677 @itemx -d [@var{pattern}]
4678 When @var{pattern} is omitted, delete all generations except the current
4681 This command accepts the same patterns as @option{--list-generations}.
4682 When @var{pattern} is specified, delete the matching generations. When
4683 @var{pattern} specifies a duration, generations @emph{older} than the
4684 specified duration match. For instance, @option{--delete-generations=1m}
4685 deletes generations that are more than one month old.
4687 If the current generation matches, it is @emph{not} deleted.
4689 Note that deleting generations prevents rolling back to them.
4690 Consequently, this command must be used with care.
4692 @xref{Invoking guix describe}, for a way to display information about the
4693 current generation only.
4695 @item --profile=@var{profile}
4696 @itemx -p @var{profile}
4697 Use @var{profile} instead of @file{~/.config/guix/current}.
4701 Show which channel commit(s) would be used and what would be built or
4702 substituted but do not actually do it.
4704 @item --allow-downgrades
4705 Allow pulling older or unrelated revisions of channels than those
4708 @cindex downgrade attacks, protection against
4709 By default, @command{guix pull} protects against so-called ``downgrade
4710 attacks'' whereby the Git repository of a channel would be reset to an
4711 earlier or unrelated revision of itself, potentially leading you to
4712 install older, known-vulnerable versions of software packages.
4715 Make sure you understand its security implications before using
4716 @option{--allow-downgrades}.
4719 @item --disable-authentication
4720 Allow pulling channel code without authenticating it.
4722 @cindex authentication, of channel code
4723 By default, @command{guix pull} authenticates code downloaded from
4724 channels by verifying that its commits are signed by authorized
4725 developers, and raises an error if this is not the case. This option
4726 instructs it to not perform any such verification.
4729 Make sure you understand its security implications before using
4730 @option{--disable-authentication}.
4733 @item --system=@var{system}
4734 @itemx -s @var{system}
4735 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
4736 the system type of the build host.
4739 Use the bootstrap Guile to build the latest Guix. This option is only
4740 useful to Guix developers.
4743 The @dfn{channel} mechanism allows you to instruct @command{guix pull} which
4744 repository and branch to pull from, as well as @emph{additional} repositories
4745 containing package modules that should be deployed. @xref{Channels}, for more
4748 In addition, @command{guix pull} supports all the common build options
4749 (@pxref{Common Build Options}).
4751 @node Invoking guix time-machine
4752 @section Invoking @command{guix time-machine}
4754 @cindex @command{guix time-machine}
4755 @cindex pinning, channels
4756 @cindex replicating Guix
4757 @cindex reproducibility, of Guix
4759 The @command{guix time-machine} command provides access to other
4760 revisions of Guix, for example to install older versions of packages,
4761 or to reproduce a computation in an identical environment. The revision
4762 of Guix to be used is defined by a commit or by a channel
4763 description file created by @command{guix describe}
4764 (@pxref{Invoking guix describe}).
4766 The general syntax is:
4769 guix time-machine @var{options}@dots{} -- @var{command} @var {arg}@dots{}
4772 where @var{command} and @var{arg}@dots{} are passed unmodified to the
4773 @command{guix} command of the specified revision. The @var{options} that define
4774 this revision are the same as for @command{guix pull} (@pxref{Invoking guix pull}):
4777 @item --url=@var{url}
4778 @itemx --commit=@var{commit}
4779 @itemx --branch=@var{branch}
4780 Use the @code{guix} channel from the specified @var{url}, at the
4781 given @var{commit} (a valid Git commit ID represented as a hexadecimal
4782 string), or @var{branch}.
4784 @item --channels=@var{file}
4785 @itemx -C @var{file}
4786 Read the list of channels from @var{file}. @var{file} must contain
4787 Scheme code that evaluates to a list of channel objects.
4788 @xref{Channels} for more information.
4791 As for @command{guix pull}, the absence of any options means that the
4792 latest commit on the master branch will be used. The command
4795 guix time-machine -- build hello
4798 will thus build the package @code{hello} as defined in the master branch,
4799 which is in general a newer revision of Guix than you have installed.
4800 Time travel works in both directions!
4802 Note that @command{guix time-machine} can trigger builds of channels and
4803 their dependencies, and these are controlled by the standard build
4804 options (@pxref{Common Build Options}).
4809 @c TODO: Remove this once we're more confident about API stability.
4811 The functionality described here is a ``technology preview'' as of version
4812 @value{VERSION}. As such, the interface is subject to change.
4816 @cindex composition of Guix revisions
4817 Sometimes you might need to mix packages from the revision of Guix you're
4818 currently running with packages available in a different revision of Guix.
4819 Guix @dfn{inferiors} allow you to achieve that by composing different Guix
4820 revisions in arbitrary ways.
4822 @cindex inferior packages
4823 Technically, an ``inferior'' is essentially a separate Guix process connected
4824 to your main Guix process through a REPL (@pxref{Invoking guix repl}). The
4825 @code{(guix inferior)} module allows you to create inferiors and to
4826 communicate with them. It also provides a high-level interface to browse and
4827 manipulate the packages that an inferior provides---@dfn{inferior packages}.
4829 When combined with channels (@pxref{Channels}), inferiors provide a simple way
4830 to interact with a separate revision of Guix. For example, let's assume you
4831 want to install in your profile the current @code{guile} package, along with
4832 the @code{guile-json} as it existed in an older revision of Guix---perhaps
4833 because the newer @code{guile-json} has an incompatible API and you want to
4834 run your code against the old API@. To do that, you could write a manifest for
4835 use by @code{guix package --manifest} (@pxref{Writing Manifests}); in that
4836 manifest, you would create an inferior for that old Guix revision you care
4837 about, and you would look up the @code{guile-json} package in the inferior:
4840 (use-modules (guix inferior) (guix channels)
4841 (srfi srfi-1)) ;for 'first'
4844 ;; This is the old revision from which we want to
4845 ;; extract guile-json.
4848 (url "https://git.savannah.gnu.org/git/guix.git")
4850 "65956ad3526ba09e1f7a40722c96c6ef7c0936fe"))))
4853 ;; An inferior representing the above revision.
4854 (inferior-for-channels channels))
4856 ;; Now create a manifest with the current "guile" package
4857 ;; and the old "guile-json" package.
4859 (list (first (lookup-inferior-packages inferior "guile-json"))
4860 (specification->package "guile")))
4863 On its first run, @command{guix package --manifest} might have to build the
4864 channel you specified before it can create the inferior; subsequent runs will
4865 be much faster because the Guix revision will be cached.
4867 The @code{(guix inferior)} module provides the following procedures to open an
4870 @deffn {Scheme Procedure} inferior-for-channels @var{channels} @
4871 [#:cache-directory] [#:ttl]
4872 Return an inferior for @var{channels}, a list of channels. Use the cache at
4873 @var{cache-directory}, where entries can be reclaimed after @var{ttl} seconds.
4874 This procedure opens a new connection to the build daemon.
4876 As a side effect, this procedure may build or substitute binaries for
4877 @var{channels}, which can take time.
4880 @deffn {Scheme Procedure} open-inferior @var{directory} @
4881 [#:command "bin/guix"]
4882 Open the inferior Guix in @var{directory}, running
4883 @code{@var{directory}/@var{command} repl} or equivalent. Return @code{#f} if
4884 the inferior could not be launched.
4887 @cindex inferior packages
4888 The procedures listed below allow you to obtain and manipulate inferior
4891 @deffn {Scheme Procedure} inferior-packages @var{inferior}
4892 Return the list of packages known to @var{inferior}.
4895 @deffn {Scheme Procedure} lookup-inferior-packages @var{inferior} @var{name} @
4897 Return the sorted list of inferior packages matching @var{name} in
4898 @var{inferior}, with highest version numbers first. If @var{version} is true,
4899 return only packages with a version number prefixed by @var{version}.
4902 @deffn {Scheme Procedure} inferior-package? @var{obj}
4903 Return true if @var{obj} is an inferior package.
4906 @deffn {Scheme Procedure} inferior-package-name @var{package}
4907 @deffnx {Scheme Procedure} inferior-package-version @var{package}
4908 @deffnx {Scheme Procedure} inferior-package-synopsis @var{package}
4909 @deffnx {Scheme Procedure} inferior-package-description @var{package}
4910 @deffnx {Scheme Procedure} inferior-package-home-page @var{package}
4911 @deffnx {Scheme Procedure} inferior-package-location @var{package}
4912 @deffnx {Scheme Procedure} inferior-package-inputs @var{package}
4913 @deffnx {Scheme Procedure} inferior-package-native-inputs @var{package}
4914 @deffnx {Scheme Procedure} inferior-package-propagated-inputs @var{package}
4915 @deffnx {Scheme Procedure} inferior-package-transitive-propagated-inputs @var{package}
4916 @deffnx {Scheme Procedure} inferior-package-native-search-paths @var{package}
4917 @deffnx {Scheme Procedure} inferior-package-transitive-native-search-paths @var{package}
4918 @deffnx {Scheme Procedure} inferior-package-search-paths @var{package}
4919 These procedures are the counterpart of package record accessors
4920 (@pxref{package Reference}). Most of them work by querying the inferior
4921 @var{package} comes from, so the inferior must still be live when you call
4925 Inferior packages can be used transparently like any other package or
4926 file-like object in G-expressions (@pxref{G-Expressions}). They are also
4927 transparently handled by the @code{packages->manifest} procedure, which is
4928 commonly used in manifests (@pxref{Invoking guix package, the
4929 @option{--manifest} option of @command{guix package}}). Thus you can insert
4930 an inferior package pretty much anywhere you would insert a regular package:
4931 in manifests, in the @code{packages} field of your @code{operating-system}
4932 declaration, and so on.
4934 @node Invoking guix describe
4935 @section Invoking @command{guix describe}
4937 @cindex reproducibility
4938 @cindex replicating Guix
4939 Often you may want to answer questions like: ``Which revision of Guix am I
4940 using?'' or ``Which channels am I using?'' This is useful information in many
4941 situations: if you want to @emph{replicate} an environment on a different
4942 machine or user account, if you want to report a bug or to determine what
4943 change in the channels you are using caused it, or if you want to record your
4944 system state for reproducibility purposes. The @command{guix describe}
4945 command answers these questions.
4947 When run from a @command{guix pull}ed @command{guix}, @command{guix describe}
4948 displays the channel(s) that it was built from, including their repository URL
4949 and commit IDs (@pxref{Channels}):
4953 Generation 10 Sep 03 2018 17:32:44 (current)
4955 repository URL: https://git.savannah.gnu.org/git/guix.git
4957 commit: e0fa68c7718fffd33d81af415279d6ddb518f727
4960 If you're familiar with the Git version control system, this is similar in
4961 spirit to @command{git describe}; the output is also similar to that of
4962 @command{guix pull --list-generations}, but limited to the current generation
4963 (@pxref{Invoking guix pull, the @option{--list-generations} option}). Because
4964 the Git commit ID shown above unambiguously refers to a snapshot of Guix, this
4965 information is all it takes to describe the revision of Guix you're using, and
4966 also to replicate it.
4968 To make it easier to replicate Guix, @command{guix describe} can also be asked
4969 to return a list of channels instead of the human-readable description above:
4972 $ guix describe -f channels
4975 (url "https://git.savannah.gnu.org/git/guix.git")
4977 "e0fa68c7718fffd33d81af415279d6ddb518f727")
4979 (make-channel-introduction
4980 "9edb3f66fd807b096b48283debdcddccfea34bad"
4981 (openpgp-fingerprint
4982 "BBB0 2DDF 2CEA F6A8 0D1D E643 A2A0 6DF2 A33A 54FA")))))
4986 You can save this to a file and feed it to @command{guix pull -C} on some
4987 other machine or at a later point in time, which will instantiate @emph{this
4988 exact Guix revision} (@pxref{Invoking guix pull, the @option{-C} option}).
4989 From there on, since you're able to deploy the same revision of Guix, you can
4990 just as well @emph{replicate a complete software environment}. We humbly
4991 think that this is @emph{awesome}, and we hope you'll like it too!
4993 The details of the options supported by @command{guix describe} are as
4997 @item --format=@var{format}
4998 @itemx -f @var{format}
4999 Produce output in the specified @var{format}, one of:
5003 produce human-readable output;
5005 produce a list of channel specifications that can be passed to @command{guix
5006 pull -C} or installed as @file{~/.config/guix/channels.scm} (@pxref{Invoking
5008 @item channels-sans-intro
5009 like @code{channels}, but omit the @code{introduction} field; use it to
5010 produce a channel specification suitable for Guix version 1.1.0 or
5011 earlier---the @code{introduction} field has to do with channel
5012 authentication (@pxref{Channels, Channel Authentication}) and is not
5013 supported by these older versions;
5016 produce a list of channel specifications in JSON format;
5018 produce a list of channel specifications in Recutils format.
5021 @item --list-formats
5022 Display available formats for @option{--format} option.
5024 @item --profile=@var{profile}
5025 @itemx -p @var{profile}
5026 Display information about @var{profile}.
5029 @node Invoking guix archive
5030 @section Invoking @command{guix archive}
5032 @cindex @command{guix archive}
5034 The @command{guix archive} command allows users to @dfn{export} files
5035 from the store into a single archive, and to later @dfn{import} them on
5036 a machine that runs Guix.
5037 In particular, it allows store files to be transferred from one machine
5038 to the store on another machine.
5041 If you're looking for a way to produce archives in a format suitable for
5042 tools other than Guix, @pxref{Invoking guix pack}.
5045 @cindex exporting store items
5046 To export store files as an archive to standard output, run:
5049 guix archive --export @var{options} @var{specifications}...
5052 @var{specifications} may be either store file names or package
5053 specifications, as for @command{guix package} (@pxref{Invoking guix
5054 package}). For instance, the following command creates an archive
5055 containing the @code{gui} output of the @code{git} package and the main
5056 output of @code{emacs}:
5059 guix archive --export git:gui /gnu/store/...-emacs-24.3 > great.nar
5062 If the specified packages are not built yet, @command{guix archive}
5063 automatically builds them. The build process may be controlled with the
5064 common build options (@pxref{Common Build Options}).
5066 To transfer the @code{emacs} package to a machine connected over SSH,
5070 guix archive --export -r emacs | ssh the-machine guix archive --import
5074 Similarly, a complete user profile may be transferred from one machine
5075 to another like this:
5078 guix archive --export -r $(readlink -f ~/.guix-profile) | \
5079 ssh the-machine guix archive --import
5083 However, note that, in both examples, all of @code{emacs} and the
5084 profile as well as all of their dependencies are transferred (due to
5085 @option{-r}), regardless of what is already available in the store on
5086 the target machine. The @option{--missing} option can help figure out
5087 which items are missing from the target store. The @command{guix copy}
5088 command simplifies and optimizes this whole process, so this is probably
5089 what you should use in this case (@pxref{Invoking guix copy}).
5091 @cindex nar, archive format
5092 @cindex normalized archive (nar)
5093 @cindex nar bundle, archive format
5094 Each store item is written in the @dfn{normalized archive} or @dfn{nar}
5095 format (described below), and the output of @command{guix archive
5096 --export} (and input of @command{guix archive --import}) is a @dfn{nar
5100 comparable in spirit to `tar', but with differences
5101 that make it more appropriate for our purposes. First, rather than
5102 recording all Unix metadata for each file, the nar format only mentions
5103 the file type (regular, directory, or symbolic link); Unix permissions
5104 and owner/group are dismissed. Second, the order in which directory
5105 entries are stored always follows the order of file names according to
5106 the C locale collation order. This makes archive production fully
5109 That nar bundle format is essentially the concatenation of zero or more
5110 nars along with metadata for each store item it contains: its file name,
5111 references, corresponding derivation, and a digital signature.
5113 When exporting, the daemon digitally signs the contents of the archive,
5114 and that digital signature is appended. When importing, the daemon
5115 verifies the signature and rejects the import in case of an invalid
5116 signature or if the signing key is not authorized.
5117 @c FIXME: Add xref to daemon doc about signatures.
5119 The main options are:
5123 Export the specified store files or packages (see below). Write the
5124 resulting archive to the standard output.
5126 Dependencies are @emph{not} included in the output, unless
5127 @option{--recursive} is passed.
5131 When combined with @option{--export}, this instructs @command{guix archive}
5132 to include dependencies of the given items in the archive. Thus, the
5133 resulting archive is self-contained: it contains the closure of the
5134 exported store items.
5137 Read an archive from the standard input, and import the files listed
5138 therein into the store. Abort if the archive has an invalid digital
5139 signature, or if it is signed by a public key not among the authorized
5140 keys (see @option{--authorize} below).
5143 Read a list of store file names from the standard input, one per line,
5144 and write on the standard output the subset of these files missing from
5147 @item --generate-key[=@var{parameters}]
5148 @cindex signing, archives
5149 Generate a new key pair for the daemon. This is a prerequisite before
5150 archives can be exported with @option{--export}. This
5151 operation is usually instantaneous but it can take time if the system's
5152 entropy pool needs to be refilled. On Guix System,
5153 @code{guix-service-type} takes care of generating this key pair the
5156 The generated key pair is typically stored under @file{/etc/guix}, in
5157 @file{signing-key.pub} (public key) and @file{signing-key.sec} (private
5158 key, which must be kept secret). When @var{parameters} is omitted,
5159 an ECDSA key using the Ed25519 curve is generated, or, for Libgcrypt
5160 versions before 1.6.0, it is a 4096-bit RSA key.
5161 Alternatively, @var{parameters} can specify
5162 @code{genkey} parameters suitable for Libgcrypt (@pxref{General
5163 public-key related Functions, @code{gcry_pk_genkey},, gcrypt, The
5164 Libgcrypt Reference Manual}).
5167 @cindex authorizing, archives
5168 Authorize imports signed by the public key passed on standard input.
5169 The public key must be in ``s-expression advanced format''---i.e., the
5170 same format as the @file{signing-key.pub} file.
5172 The list of authorized keys is kept in the human-editable file
5173 @file{/etc/guix/acl}. The file contains
5174 @url{https://people.csail.mit.edu/rivest/Sexp.txt, ``advanced-format
5175 s-expressions''} and is structured as an access-control list in the
5176 @url{https://theworld.com/~cme/spki.txt, Simple Public-Key Infrastructure
5179 @item --extract=@var{directory}
5180 @itemx -x @var{directory}
5181 Read a single-item archive as served by substitute servers
5182 (@pxref{Substitutes}) and extract it to @var{directory}. This is a
5183 low-level operation needed in only very narrow use cases; see below.
5185 For example, the following command extracts the substitute for Emacs
5186 served by @code{@value{SUBSTITUTE-SERVER-1}} to @file{/tmp/emacs}:
5190 https://@value{SUBSTITUTE-SERVER-1}/nar/gzip/@dots{}-emacs-24.5 \
5191 | gunzip | guix archive -x /tmp/emacs
5194 Single-item archives are different from multiple-item archives produced
5195 by @command{guix archive --export}; they contain a single store item,
5196 and they do @emph{not} embed a signature. Thus this operation does
5197 @emph{no} signature verification and its output should be considered
5200 The primary purpose of this operation is to facilitate inspection of
5201 archive contents coming from possibly untrusted substitute servers
5202 (@pxref{Invoking guix challenge}).
5206 Read a single-item archive as served by substitute servers
5207 (@pxref{Substitutes}) and print the list of files it contains, as in
5212 https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-emacs-26.3 \
5213 | lzip -d | guix archive -t
5218 @c *********************************************************************
5223 @cindex @file{channels.scm}, configuration file
5224 @cindex configuration file for channels
5225 @cindex @command{guix pull}, configuration file
5226 @cindex configuration of @command{guix pull}
5227 Guix and its package collection are updated by running @command{guix pull}
5228 (@pxref{Invoking guix pull}). By default @command{guix pull} downloads and
5229 deploys Guix itself from the official GNU@tie{}Guix repository. This can be
5230 customized by defining @dfn{channels} in the
5231 @file{~/.config/guix/channels.scm} file. A channel specifies a URL and branch
5232 of a Git repository to be deployed, and @command{guix pull} can be instructed
5233 to pull from one or more channels. In other words, channels can be used
5234 to @emph{customize} and to @emph{extend} Guix, as we will see below.
5235 Guix is able to take into account security concerns and deal with authenticated
5239 * Specifying Additional Channels:: Extending the package collection.
5240 * Using a Custom Guix Channel:: Using a customized Guix.
5241 * Replicating Guix:: Running the @emph{exact same} Guix.
5242 * Channel Authentication:: How Guix verifies what it fetches.
5243 * Channels with Substitutes:: Using channels with available substitutes.
5244 * Creating a Channel:: How to write your custom channel.
5245 * Package Modules in a Sub-directory:: Specifying the channel's package modules location.
5246 * Declaring Channel Dependencies:: How to depend on other channels.
5247 * Specifying Channel Authorizations:: Defining channel authors authorizations.
5248 * Primary URL:: Distinguishing mirror to original.
5249 * Writing Channel News:: Communicating information to channel's users.
5252 @node Specifying Additional Channels
5253 @section Specifying Additional Channels
5255 @cindex extending the package collection (channels)
5256 @cindex variant packages (channels)
5257 You can specify @emph{additional channels} to pull from. To use a channel, write
5258 @code{~/.config/guix/channels.scm} to instruct @command{guix pull} to pull from it
5259 @emph{in addition} to the default Guix channel(s):
5261 @vindex %default-channels
5263 ;; Add variant packages to those Guix provides.
5265 (name 'variant-packages)
5266 (url "https://example.org/variant-packages.git"))
5271 Note that the snippet above is (as always!)@: Scheme code; we use @code{cons} to
5272 add a channel the list of channels that the variable @code{%default-channels}
5273 is bound to (@pxref{Pairs, @code{cons} and lists,, guile, GNU Guile Reference
5274 Manual}). With this file in place, @command{guix pull} builds not only Guix
5275 but also the package modules from your own repository. The result in
5276 @file{~/.config/guix/current} is the union of Guix with your own package
5281 Generation 19 Aug 27 2018 16:20:48
5283 repository URL: https://git.savannah.gnu.org/git/guix.git
5285 commit: d894ab8e9bfabcefa6c49d9ba2e834dd5a73a300
5286 variant-packages dd3df5e
5287 repository URL: https://example.org/variant-packages.git
5289 commit: dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb
5293 The output of @command{guix describe} above shows that we're now running
5294 Generation@tie{}19 and that it includes
5295 both Guix and packages from the @code{variant-personal-packages} channel
5296 (@pxref{Invoking guix describe}).
5298 @node Using a Custom Guix Channel
5299 @section Using a Custom Guix Channel
5301 The channel called @code{guix} specifies where Guix itself---its command-line
5302 tools as well as its package collection---should be downloaded. For instance,
5303 suppose you want to update from another copy of the Guix repository at
5304 @code{example.org}, and specifically the @code{super-hacks} branch, you can
5305 write in @code{~/.config/guix/channels.scm} this specification:
5308 ;; Tell 'guix pull' to use another repo.
5311 (url "https://example.org/another-guix.git")
5312 (branch "super-hacks")))
5316 From there on, @command{guix pull} will fetch code from the @code{super-hacks}
5317 branch of the repository at @code{example.org}. The authentication concern is
5318 addressed below (@pxref{Channel Authentication}).
5320 @node Replicating Guix
5321 @section Replicating Guix
5323 @cindex pinning, channels
5324 @cindex replicating Guix
5325 @cindex reproducibility, of Guix
5326 The @command{guix describe} command shows precisely which commits were
5327 used to build the instance of Guix we're using (@pxref{Invoking guix
5328 describe}). We can replicate this instance on another machine or at a
5329 different point in time by providing a channel specification ``pinned''
5330 to these commits that looks like this:
5333 ;; Deploy specific commits of my channels of interest.
5336 (url "https://git.savannah.gnu.org/git/guix.git")
5337 (commit "6298c3ffd9654d3231a6f25390b056483e8f407c"))
5339 (name 'variant-packages)
5340 (url "https://example.org/variant-packages.git")
5341 (commit "dd3df5e2c8818760a8fc0bd699e55d3b69fef2bb")))
5344 To obtain this pinned channel specification, the easiest way is to run
5345 @command{guix describe} and to save its output in the @code{channels}
5346 format in a file, like so:
5349 guix describe -f channels > channels.scm
5352 The resulting @file{channels.scm} file can be passed to the @option{-C}
5353 option of @command{guix pull} (@pxref{Invoking guix pull}) or
5354 @command{guix time-machine} (@pxref{Invoking guix time-machine}), as in
5358 guix time-machine -C channels.scm -- shell python -- python3
5361 Given the @file{channels.scm} file, the command above will always fetch
5362 the @emph{exact same Guix instance}, then use that instance to run the
5363 exact same Python (@pxref{Invoking guix shell}). On any machine, at any
5364 time, it ends up running the exact same binaries, bit for bit.
5367 Pinned channels address a problem similar to ``lock files'' as
5368 implemented by some deployment tools---they let you pin and reproduce a
5369 set of packages. In the case of Guix though, you are effectively
5370 pinning the entire package set as defined at the given channel commits;
5371 in fact, you are pinning all of Guix, including its core modules and
5372 command-line tools. You're also getting strong guarantees that you are,
5373 indeed, obtaining the exact same software.
5375 This gives you super powers, allowing you to track the provenance of binary
5376 artifacts with very fine grain, and to reproduce software environments at
5377 will---some sort of ``meta reproducibility'' capabilities, if you will.
5378 @xref{Inferiors}, for another way to take advantage of these super powers.
5380 @node Channel Authentication
5381 @section Channel Authentication
5383 @anchor{channel-authentication}
5384 @cindex authentication, of channel code
5385 The @command{guix pull} and @command{guix time-machine} commands
5386 @dfn{authenticate} the code retrieved from channels: they make sure each
5387 commit that is fetched is signed by an authorized developer. The goal
5388 is to protect from unauthorized modifications to the channel that would
5389 lead users to run malicious code.
5391 As a user, you must provide a @dfn{channel introduction} in your
5392 channels file so that Guix knows how to authenticate its first commit.
5393 A channel specification, including its introduction, looks something
5398 (name 'some-channel)
5399 (url "https://example.org/some-channel.git")
5401 (make-channel-introduction
5402 "6f0d8cc0d88abb59c324b2990bfee2876016bb86"
5403 (openpgp-fingerprint
5404 "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5407 The specification above shows the name and URL of the channel. The call
5408 to @code{make-channel-introduction} above specifies that authentication
5409 of this channel starts at commit @code{6f0d8cc@dots{}}, which is signed
5410 by the OpenPGP key with fingerprint @code{CABB A931@dots{}}.
5412 For the main channel, called @code{guix}, you automatically get that
5413 information from your Guix installation. For other channels, include
5414 the channel introduction provided by the channel authors in your
5415 @file{channels.scm} file. Make sure you retrieve the channel
5416 introduction from a trusted source since that is the root of your trust.
5418 If you're curious about the authentication mechanics, read on!
5420 @node Channels with Substitutes
5421 @section Channels with Substitutes
5423 When running @command{guix pull}, Guix will first compile the
5424 definitions of every available package. This is an expensive operation
5425 for which substitutes (@pxref{Substitutes}) may be available. The
5426 following snippet in @file{channels.scm} will ensure that @command{guix
5427 pull} uses the latest commit with available substitutes for the package
5428 definitions: this is done by querying the continuous integration
5429 server at @url{https://ci.guix.gnu.org}.
5432 (use-modules (guix ci))
5434 (list (channel-with-substitutes-available
5435 %default-guix-channel
5436 "https://ci.guix.gnu.org"))
5439 Note that this does not mean that all the packages that you will
5440 install after running @command{guix pull} will have available
5441 substitutes. It only ensures that @command{guix pull} will not try to
5442 compile package definitions. This is particularly useful when using
5443 machines with limited resources.
5445 @node Creating a Channel
5446 @section Creating a Channel
5448 @cindex personal packages (channels)
5449 @cindex channels, for personal packages
5450 Let's say you have a bunch of custom package variants or personal packages
5451 that you think would make little sense to contribute to the Guix project, but
5452 would like to have these packages transparently available to you at the
5453 command line. You would first write modules containing those package
5454 definitions (@pxref{Package Modules}), maintain them in a Git repository, and
5455 then you and anyone else can use it as an additional channel to get packages
5458 @c What follows stems from discussions at
5459 @c <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=22629#134> as well as
5460 @c earlier discussions on guix-devel@gnu.org.
5462 Before you, dear user, shout---``woow this is @emph{soooo coool}!''---and
5463 publish your personal channel to the world, we would like to share a few words
5468 Before publishing a channel, please consider contributing your package
5469 definitions to Guix proper (@pxref{Contributing}). Guix as a project is open
5470 to free software of all sorts, and packages in Guix proper are readily
5471 available to all Guix users and benefit from the project's quality assurance
5475 When you maintain package definitions outside Guix, we, Guix developers,
5476 consider that @emph{the compatibility burden is on you}. Remember that
5477 package modules and package definitions are just Scheme code that uses various
5478 programming interfaces (APIs). We want to remain free to change these APIs to
5479 keep improving Guix, possibly in ways that break your channel. We never
5480 change APIs gratuitously, but we will @emph{not} commit to freezing APIs
5484 Corollary: if you're using an external channel and that channel breaks, please
5485 @emph{report the issue to the channel authors}, not to the Guix project.
5488 You've been warned! Having said this, we believe external channels are a
5489 practical way to exert your freedom to augment Guix' package collection and to
5490 share your improvements, which are basic tenets of
5491 @uref{https://www.gnu.org/philosophy/free-sw.html, free software}. Please
5492 email us at @email{guix-devel@@gnu.org} if you'd like to discuss this.
5495 To create a channel, create a Git repository containing your own package
5496 modules and make it available. The repository can contain anything, but a
5497 useful channel will contain Guile modules that export packages. Once you
5498 start using a channel, Guix will behave as if the root directory of that
5499 channel's Git repository has been added to the Guile load path (@pxref{Load
5500 Paths,,, guile, GNU Guile Reference Manual}). For example, if your channel
5501 contains a file at @file{my-packages/my-tools.scm} that defines a Guile
5502 module, then the module will be available under the name @code{(my-packages
5503 my-tools)}, and you will be able to use it like any other module
5504 (@pxref{Modules,,, guile, GNU Guile Reference Manual}).
5506 As a channel author, consider bundling authentication material with your
5507 channel so that users can authenticate it. @xref{Channel
5508 Authentication}, and @ref{Specifying Channel Authorizations}, for info
5512 @node Package Modules in a Sub-directory
5513 @section Package Modules in a Sub-directory
5515 @cindex subdirectory, channels
5516 As a channel author, you may want to keep your channel modules in a
5517 sub-directory. If your modules are in the sub-directory @file{guix}, you must
5518 add a meta-data file @file{.guix-channel} that contains:
5526 @node Declaring Channel Dependencies
5527 @section Declaring Channel Dependencies
5529 @cindex dependencies, channels
5530 @cindex meta-data, channels
5531 Channel authors may decide to augment a package collection provided by other
5532 channels. They can declare their channel to be dependent on other channels in
5533 a meta-data file @file{.guix-channel}, which is to be placed in the root of
5534 the channel repository.
5536 The meta-data file should contain a simple S-expression like this:
5543 (name some-collection)
5544 (url "https://example.org/first-collection.git")
5546 ;; The 'introduction' bit below is optional: you would
5547 ;; provide it for dependencies that can be authenticated.
5549 (channel-introduction
5551 (commit "a8883b58dc82e167c96506cf05095f37c2c2c6cd")
5552 (signer "CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"))))
5554 (name some-other-collection)
5555 (url "https://example.org/second-collection.git")
5556 (branch "testing"))))
5559 In the above example this channel is declared to depend on two other channels,
5560 which will both be fetched automatically. The modules provided by the channel
5561 will be compiled in an environment where the modules of all these declared
5562 channels are available.
5564 For the sake of reliability and maintainability, you should avoid dependencies
5565 on channels that you don't control, and you should aim to keep the number of
5566 dependencies to a minimum.
5568 @node Specifying Channel Authorizations
5569 @section Specifying Channel Authorizations
5571 @cindex channel authorizations
5572 @anchor{channel-authorizations}
5573 As we saw above, Guix ensures the source code it pulls from channels
5574 comes from authorized developers. As a channel author, you need to
5575 specify the list of authorized developers in the
5576 @file{.guix-authorizations} file in the channel's Git repository. The
5577 authentication rule is simple: each commit must be signed by a key
5578 listed in the @file{.guix-authorizations} file of its parent
5579 commit(s)@footnote{Git commits form a @dfn{directed acyclic graph}
5580 (DAG). Each commit can have zero or more parents; ``regular'' commits
5581 have one parent and merge commits have two parent commits. Read
5582 @uref{https://eagain.net/articles/git-for-computer-scientists/, @i{Git
5583 for Computer Scientists}} for a great overview.} The
5584 @file{.guix-authorizations} file looks like this:
5587 ;; Example '.guix-authorizations' file.
5590 (version 0) ;current file format version
5592 (("AD17 A21E F8AE D8F1 CC02 DBD9 F8AE D8F1 765C 61E3"
5594 ("2A39 3FFF 68F4 EF7A 3D29 12AF 68F4 EF7A 22FB B2D5"
5596 ("CABB A931 C0FF EEC6 900D 0CFB 090B 1199 3D9A EBB5"
5600 Each fingerprint is followed by optional key/value pairs, as in the
5601 example above. Currently these key/value pairs are ignored.
5603 This authentication rule creates a chicken-and-egg issue: how do we
5604 authenticate the first commit? Related to that: how do we deal with
5605 channels whose repository history contains unsigned commits and lack
5606 @file{.guix-authorizations}? And how do we fork existing channels?
5608 @cindex channel introduction
5609 Channel introductions answer these questions by describing the first
5610 commit of a channel that should be authenticated. The first time a
5611 channel is fetched with @command{guix pull} or @command{guix
5612 time-machine}, the command looks up the introductory commit and verifies
5613 that it is signed by the specified OpenPGP key. From then on, it
5614 authenticates commits according to the rule above. Authentication fails
5615 if the target commit is neither a descendant nor an ancestor of the
5616 introductory commit.
5618 Additionally, your channel must provide all the OpenPGP keys that were
5619 ever mentioned in @file{.guix-authorizations}, stored as @file{.key}
5620 files, which can be either binary or ``ASCII-armored''. By default,
5621 those @file{.key} files are searched for in the branch named
5622 @code{keyring} but you can specify a different branch name in
5623 @code{.guix-channel} like so:
5628 (keyring-reference "my-keyring-branch"))
5631 To summarize, as the author of a channel, there are three things you have
5632 to do to allow users to authenticate your code:
5636 Export the OpenPGP keys of past and present committers with @command{gpg
5637 --export} and store them in @file{.key} files, by default in a branch
5638 named @code{keyring} (we recommend making it an @dfn{orphan branch}).
5641 Introduce an initial @file{.guix-authorizations} in the channel's
5642 repository. Do that in a signed commit (@pxref{Commit Access}, for
5643 information on how to sign Git commits.)
5646 Advertise the channel introduction, for instance on your channel's web
5647 page. The channel introduction, as we saw above, is the commit/key
5648 pair---i.e., the commit that introduced @file{.guix-authorizations}, and
5649 the fingerprint of the OpenPGP used to sign it.
5652 Before pushing to your public Git repository, you can run @command{guix
5653 git-authenticate} to verify that you did sign all the commits you are
5654 about to push with an authorized key:
5657 guix git authenticate @var{commit} @var{signer}
5661 where @var{commit} and @var{signer} are your channel introduction.
5662 @xref{Invoking guix git authenticate}, for details.
5664 Publishing a signed channel requires discipline: any mistake, such as an
5665 unsigned commit or a commit signed by an unauthorized key, will prevent
5666 users from pulling from your channel---well, that's the whole point of
5667 authentication! Pay attention to merges in particular: merge commits
5668 are considered authentic if and only if they are signed by a key present
5669 in the @file{.guix-authorizations} file of @emph{both} branches.
5672 @section Primary URL
5674 @cindex primary URL, channels
5675 Channel authors can indicate the primary URL of their channel's Git
5676 repository in the @file{.guix-channel} file, like so:
5681 (url "https://example.org/guix.git"))
5684 This allows @command{guix pull} to determine whether it is pulling code
5685 from a mirror of the channel; when that is the case, it warns the user
5686 that the mirror might be stale and displays the primary URL@. That way,
5687 users cannot be tricked into fetching code from a stale mirror that does
5688 not receive security updates.
5690 This feature only makes sense for authenticated repositories, such as
5691 the official @code{guix} channel, for which @command{guix pull} ensures
5692 the code it fetches is authentic.
5694 @node Writing Channel News
5695 @section Writing Channel News
5697 @cindex news, for channels
5698 Channel authors may occasionally want to communicate to their users
5699 information about important changes in the channel. You'd send them all
5700 an email, but that's not convenient.
5702 Instead, channels can provide a @dfn{news file}; when the channel users
5703 run @command{guix pull}, that news file is automatically read and
5704 @command{guix pull --news} can display the announcements that correspond
5705 to the new commits that have been pulled, if any.
5707 To do that, channel authors must first declare the name of the news file
5708 in their @file{.guix-channel} file:
5713 (news-file "etc/news.txt"))
5716 The news file itself, @file{etc/news.txt} in this example, must look
5717 something like this:
5722 (entry (tag "the-bug-fix")
5723 (title (en "Fixed terrible bug")
5725 (body (en "@@emph@{Good news@}! It's fixed!")
5726 (eo "Certe ĝi pli bone funkcias nun!")))
5727 (entry (commit "bdcabe815cd28144a2d2b4bc3c5057b051fa9906")
5728 (title (en "Added a great package")
5729 (ca "Què vol dir guix?"))
5730 (body (en "Don't miss the @@code@{hello@} package!"))))
5733 While the news file is using the Scheme syntax, avoid naming it with a
5734 @file{.scm} extension or else it will get picked up when building the
5735 channel and yield an error since it is not a valid module.
5736 Alternatively, you can move the channel module to a subdirectory and
5737 store the news file in another directory.
5739 The file consists of a list of @dfn{news entries}. Each entry is
5740 associated with a commit or tag: it describes changes made in this
5741 commit, possibly in preceding commits as well. Users see entries only
5742 the first time they obtain the commit the entry refers to.
5744 The @code{title} field should be a one-line summary while @code{body}
5745 can be arbitrarily long, and both can contain Texinfo markup
5746 (@pxref{Overview,,, texinfo, GNU Texinfo}). Both the title and body are
5747 a list of language tag/message tuples, which allows @command{guix pull}
5748 to display news in the language that corresponds to the user's locale.
5750 If you want to translate news using a gettext-based workflow, you can
5751 extract translatable strings with @command{xgettext} (@pxref{xgettext
5752 Invocation,,, gettext, GNU Gettext Utilities}). For example, assuming
5753 you write news entries in English first, the command below creates a PO
5754 file containing the strings to translate:
5757 xgettext -o news.po -l scheme -ken etc/news.txt
5760 To sum up, yes, you could use your channel as a blog. But beware, this
5761 is @emph{not quite} what your users might expect.
5763 @c *********************************************************************
5765 @chapter Development
5767 @cindex software development
5768 If you are a software developer, Guix provides tools that you should find
5769 helpful---independently of the language you're developing in. This is what
5770 this chapter is about.
5772 The @command{guix shell} command provides a convenient way to set up
5773 one-off software environments, be it for development purposes or to run
5774 a command without installing it in your profile. The @command{guix
5775 pack} command allows you to create @dfn{application bundles} that can be
5776 easily distributed to users who do not run Guix.
5779 * Invoking guix shell:: Spawning one-off software environments.
5780 * Invoking guix environment:: Setting up development environments.
5781 * Invoking guix pack:: Creating software bundles.
5782 * The GCC toolchain:: Working with languages supported by GCC.
5783 * Invoking guix git authenticate:: Authenticating Git repositories.
5786 @node Invoking guix shell
5787 @section Invoking @command{guix shell}
5789 @cindex reproducible build environments
5790 @cindex development environments
5791 @cindex @command{guix environment}
5792 @cindex environment, package build environment
5793 The purpose of @command{guix shell} is to make it easy to create one-off
5794 software environments, without changing one's profile. It is typically
5795 used to create development environments; it is also a convenient way to
5796 run applications without ``polluting'' your profile.
5799 The @command{guix shell} command was recently introduced to supersede
5800 @command{guix environment} (@pxref{Invoking guix environment}). If you
5801 are familiar with @command{guix environment}, you will notice that it is
5802 similar but also---we hope!---more convenient.
5805 The general syntax is:
5808 guix shell [@var{options}] [@var{package}@dots{}]
5811 The following example creates an environment containing Python and NumPy,
5812 building or downloading any missing package, and runs the
5813 @command{python3} command in that environment:
5816 guix shell python python-numpy -- python3
5819 Development environments can be created as in the example below, which
5820 spawns an interactive shell containing all the dependencies and
5821 environment variables needed to work on Inkscape:
5824 guix shell --development inkscape
5827 Exiting the shell places the user back in the original environment
5828 before @command{guix shell} was invoked. The next garbage collection
5829 (@pxref{Invoking guix gc}) may clean up packages that were installed in
5830 the environment and that are no longer used outside of it.
5832 As an added convenience, @command{guix shell} will try to do what you
5833 mean when it is invoked interactively without any other arguments
5840 If it finds a @file{manifest.scm} in the current working directory or
5841 any of its parents, it uses this manifest as though it was given via @code{--manifest}.
5842 Likewise, if it finds a @file{guix.scm} in the same directories, it uses
5843 it to build a development profile as though both @code{--development}
5844 and @code{--file} were present.
5845 In either case, the file will only be loaded if the directory it
5846 resides in is listed in
5847 @file{~/.config/guix/shell-authorized-directories}.
5848 This provides an easy way to define, share, and enter development
5851 By default, the shell session or command runs in an @emph{augmented}
5852 environment, where the new packages are added to search path environment
5853 variables such as @code{PATH}. You can, instead, choose to create an
5854 @emph{isolated} environment containing nothing but the packages you
5855 asked for. Passing the @option{--pure} option clears environment
5856 variable definitions found in the parent environment@footnote{Be sure to
5857 use the @option{--check} option the first time you use @command{guix
5858 shell} interactively to make sure the shell does not undo the effect of
5859 @option{--pure}.}; passing @option{--container} goes one step further by
5860 spawning a @dfn{container} isolated from the rest of the system:
5863 guix shell --container emacs gcc-toolchain
5866 The command above spawns an interactive shell in a container where
5867 nothing but @code{emacs}, @code{gcc-toolchain}, and their dependencies
5868 is available. The container lacks network access and shares no files
5869 other than the current working directory with the surrounding
5870 environment. This is useful to prevent access to system-wide resources
5871 such as @file{/usr/bin} on foreign distros.
5873 This @option{--container} option can also prove useful if you wish to
5874 run a security-sensitive application, such as a web browser, in an
5875 isolated environment. For example, the command below launches
5876 Ungoogled-Chromium in an isolated environment, this time sharing network
5877 access with the host and preserving its @code{DISPLAY} environment
5878 variable, but without even sharing the current directory:
5881 guix shell --container --network --no-cwd ungoogled-chromium \
5882 --preserve='^DISPLAY$' -- chromium
5885 @vindex GUIX_ENVIRONMENT
5886 @command{guix shell} defines the @env{GUIX_ENVIRONMENT}
5887 variable in the shell it spawns; its value is the file name of the
5888 profile of this environment. This allows users to, say, define a
5889 specific prompt for development environments in their @file{.bashrc}
5890 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
5893 if [ -n "$GUIX_ENVIRONMENT" ]
5895 export PS1="\u@@\h \w [dev]\$ "
5900 ...@: or to browse the profile:
5903 $ ls "$GUIX_ENVIRONMENT/bin"
5906 The available options are summarized below.
5910 Set up the environment and check whether the shell would clobber
5911 environment variables. It's a good idea to use this option the first
5912 time you run @command{guix shell} for an interactive session to make
5913 sure your setup is correct.
5915 For example, if the shell modifies the @env{PATH} environment variable,
5916 report it since you would get a different environment than what you
5919 Such problems usually indicate that the shell startup files are
5920 unexpectedly modifying those environment variables. For example, if you
5921 are using Bash, make sure that environment variables are set or modified
5922 in @file{~/.bash_profile} and @emph{not} in @file{~/.bashrc}---the
5923 former is sourced only by log-in shells. @xref{Bash Startup Files,,,
5924 bash, The GNU Bash Reference Manual}, for details on Bash start-up
5927 @anchor{shell-development-option}
5930 Cause @command{guix shell} to include in the environment the
5931 dependencies of the following package rather than the package itself.
5932 This can be combined with other packages. For instance, the command
5933 below starts an interactive shell containing the build-time dependencies
5934 of GNU@tie{}Guile, plus Autoconf, Automake, and Libtool:
5937 guix shell -D guile autoconf automake libtool
5940 @item --expression=@var{expr}
5941 @itemx -e @var{expr}
5942 Create an environment for the package or list of packages that
5943 @var{expr} evaluates to.
5945 For example, running:
5948 guix shell -D -e '(@@ (gnu packages maths) petsc-openmpi)'
5951 starts a shell with the environment for this specific variant of the
5957 guix shell -e '(@@ (gnu) %base-packages)'
5960 starts a shell with all the base system packages available.
5962 The above commands only use the default output of the given packages.
5963 To select other outputs, two element tuples can be specified:
5966 guix shell -e '(list (@@ (gnu packages bash) bash) "include")'
5969 @xref{package-development-manifest,
5970 @code{package->development-manifest}}, for information on how to write a
5971 manifest for the development environment of a package.
5973 @item --file=@var{file}
5974 @itemx -f @var{file}
5975 Create an environment containing the package or list of packages that
5976 the code within @var{file} evaluates to.
5978 As an example, @var{file} might contain a definition like this
5979 (@pxref{Defining Packages}):
5982 @verbatiminclude environment-gdb.scm
5985 With the file above, you can enter a development environment for GDB by
5989 guix shell -D -f gdb-devel.scm
5992 @anchor{shell-manifest}
5993 @item --manifest=@var{file}
5994 @itemx -m @var{file}
5995 Create an environment for the packages contained in the manifest object
5996 returned by the Scheme code in @var{file}. This option can be repeated
5997 several times, in which case the manifests are concatenated.
5999 This is similar to the same-named option in @command{guix package}
6000 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
6003 @xref{Writing Manifests}, for information on how to write a manifest.
6004 See @option{--export-manifest} below on how to obtain a first manifest.
6006 @cindex manifest, exporting
6007 @anchor{shell-export-manifest}
6008 @item --export-manifest
6009 Write to standard output a manifest suitable for @option{--manifest}
6010 corresponding to given command-line options.
6012 This is a way to ``convert'' command-line arguments into a manifest.
6013 For example, imagine you are tired of typing long lines and would like
6014 to get a manifest equivalent to this command line:
6017 guix shell -D guile git emacs emacs-geiser emacs-geiser-guile
6020 Just add @option{--export-manifest} to the command line above:
6023 guix shell --export-manifest \
6024 -D guile git emacs emacs-geiser emacs-geiser-guile
6028 ... and you get a manifest along these lines:
6031 (concatenate-manifests
6032 (list (specifications->manifest
6036 "emacs-geiser-guile"))
6037 (package->development-manifest
6038 (specification->package "guile"))))
6041 You can store it into a file, say @file{manifest.scm}, and from there
6042 pass it to @command{guix shell} or indeed pretty much any @command{guix}
6046 guix shell -m manifest.scm
6049 Voilà, you've converted a long command line into a manifest! That
6050 conversion process honors package transformation options (@pxref{Package
6051 Transformation Options}) so it should be lossless.
6053 @item --profile=@var{profile}
6054 @itemx -p @var{profile}
6055 Create an environment containing the packages installed in @var{profile}.
6056 Use @command{guix package} (@pxref{Invoking guix package}) to create
6057 and manage profiles.
6060 Unset existing environment variables when building the new environment, except
6061 those specified with @option{--preserve} (see below). This has the effect of
6062 creating an environment in which search paths only contain package inputs.
6064 @item --preserve=@var{regexp}
6065 @itemx -E @var{regexp}
6066 When used alongside @option{--pure}, preserve the environment variables
6067 matching @var{regexp}---in other words, put them on a ``white list'' of
6068 environment variables that must be preserved. This option can be repeated
6072 guix shell --pure --preserve=^SLURM openmpi @dots{} \
6076 This example runs @command{mpirun} in a context where the only environment
6077 variables defined are @env{PATH}, environment variables whose name starts
6078 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
6081 @item --search-paths
6082 Display the environment variable definitions that make up the
6085 @item --system=@var{system}
6086 @itemx -s @var{system}
6087 Attempt to build for @var{system}---e.g., @code{i686-linux}.
6092 Run @var{command} within an isolated container. The current working
6093 directory outside the container is mapped inside the container.
6094 Additionally, unless overridden with @option{--user}, a dummy home
6095 directory is created that matches the current user's home directory, and
6096 @file{/etc/passwd} is configured accordingly.
6098 The spawned process runs as the current user outside the container. Inside
6099 the container, it has the same UID and GID as the current user, unless
6100 @option{--user} is passed (see below).
6104 For containers, share the network namespace with the host system.
6105 Containers created without this flag only have access to the loopback
6108 @item --link-profile
6110 For containers, link the environment profile to @file{~/.guix-profile}
6111 within the container and set @code{GUIX_ENVIRONMENT} to that.
6112 This is equivalent to making @file{~/.guix-profile} a symlink to the
6113 actual profile within the container.
6114 Linking will fail and abort the environment if the directory already
6115 exists, which will certainly be the case if @command{guix shell}
6116 was invoked in the user's home directory.
6118 Certain packages are configured to look in @file{~/.guix-profile} for
6119 configuration files and data;@footnote{For example, the
6120 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
6121 for additional fonts.} @option{--link-profile} allows these programs to
6122 behave as expected within the environment.
6124 @item --user=@var{user}
6125 @itemx -u @var{user}
6126 For containers, use the username @var{user} in place of the current
6127 user. The generated @file{/etc/passwd} entry within the container will
6128 contain the name @var{user}, the home directory will be
6129 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
6130 the UID and GID inside the container are 1000. @var{user}
6131 need not exist on the system.
6133 Additionally, any shared or exposed path (see @option{--share} and
6134 @option{--expose} respectively) whose target is within the current user's
6135 home directory will be remapped relative to @file{/home/USER}; this
6136 includes the automatic mapping of the current working directory.
6139 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
6141 guix shell --container --user=foo \
6142 --expose=$HOME/test \
6143 --expose=/tmp/target=$HOME/target
6146 While this will limit the leaking of user identity through home paths
6147 and each of the user fields, this is only one useful component of a
6148 broader privacy/anonymity solution---not one in and of itself.
6151 For containers, the default behavior is to share the current working
6152 directory with the isolated container and immediately change to that
6153 directory within the container. If this is undesirable,
6154 @option{--no-cwd} will cause the current working directory to @emph{not}
6155 be automatically shared and will change to the user's home directory
6156 within the container instead. See also @option{--user}.
6158 @item --expose=@var{source}[=@var{target}]
6159 @itemx --share=@var{source}[=@var{target}]
6160 For containers, @option{--expose} (resp. @option{--share}) exposes the
6161 file system @var{source} from the host system as the read-only
6162 (resp. writable) file system @var{target} within the container. If
6163 @var{target} is not specified, @var{source} is used as the target mount
6164 point in the container.
6166 The example below spawns a Guile REPL in a container in which the user's
6167 home directory is accessible read-only via the @file{/exchange}
6171 guix shell --container --expose=$HOME=/exchange guile -- guile
6174 @item --rebuild-cache
6175 @cindex caching, of profiles
6176 @cindex caching, in @command{guix shell}
6177 In most cases, @command{guix shell} caches the environment so that
6178 subsequent uses are instantaneous. Least-recently used cache entries
6179 are periodically removed. The cache is also invalidated, when using
6180 @option{--file} or @option{--manifest}, anytime the corresponding file
6183 The @option{--rebuild-cache} forces the cached environment to be
6184 refreshed. This is useful when using @option{--file} or
6185 @option{--manifest} and the @command{guix.scm} or @command{manifest.scm}
6186 file has external dependencies, or if its behavior depends, say, on
6187 environment variables.
6189 @item --root=@var{file}
6190 @itemx -r @var{file}
6191 @cindex persistent environment
6192 @cindex garbage collector root, for environments
6193 Make @var{file} a symlink to the profile for this environment, and
6194 register it as a garbage collector root.
6196 This is useful if you want to protect your environment from garbage
6197 collection, to make it ``persistent''.
6199 When this option is omitted, @command{guix shell} caches profiles so
6200 that subsequent uses of the same environment are instantaneous---this is
6201 comparable to using @option{--root} except that @command{guix shell}
6202 takes care of periodically removing the least-recently used garbage
6205 In some cases, @command{guix shell} does not cache profiles---e.g., if
6206 transformation options such as @option{--with-latest} are used. In
6207 those cases, the environment is protected from garbage collection only
6208 for the duration of the @command{guix shell} session. This means that
6209 next time you recreate the same environment, you could have to rebuild
6210 or re-download packages.
6212 @xref{Invoking guix gc}, for more on GC roots.
6215 @command{guix shell} also supports all of the common build options that
6216 @command{guix build} supports (@pxref{Common Build Options}) as well as
6217 package transformation options (@pxref{Package Transformation Options}).
6219 @node Invoking guix environment
6220 @section Invoking @command{guix environment}
6222 The purpose of @command{guix environment} is to assist in creating
6223 development environments.
6225 @quotation Deprecation warning
6226 The @command{guix environment} command is deprecated in favor of
6227 @command{guix shell}, which performs similar functions but is more
6228 convenient to use. @xref{Invoking guix shell}.
6230 Being deprecated, @command{guix environment} is slated for eventual
6231 removal, but the Guix project is committed to keeping it until May 1st,
6232 2023. Please get in touch with us at @email{guix-devel@@gnu.org} if you
6233 would like to discuss it.
6236 The general syntax is:
6239 guix environment @var{options} @var{package}@dots{}
6242 The following example spawns a new shell set up for the development of
6246 guix environment guile
6249 If the needed dependencies are not built yet, @command{guix environment}
6250 automatically builds them. The environment of the new shell is an
6251 augmented version of the environment that @command{guix environment} was
6252 run in. It contains the necessary search paths for building the given
6253 package added to the existing environment variables. To create
6254 a ``pure'' environment, in which the original environment variables have
6255 been unset, use the @option{--pure} option@footnote{Users sometimes
6256 wrongfully augment environment variables such as @env{PATH} in their
6257 @file{~/.bashrc} file. As a consequence, when @command{guix
6258 environment} launches it, Bash may read @file{~/.bashrc}, thereby
6259 introducing ``impurities'' in these environment variables. It is an
6260 error to define such environment variables in @file{.bashrc}; instead,
6261 they should be defined in @file{.bash_profile}, which is sourced only by
6262 log-in shells. @xref{Bash Startup Files,,, bash, The GNU Bash Reference
6263 Manual}, for details on Bash start-up files.}.
6265 Exiting from a Guix environment is the same as exiting from the shell,
6266 and will place the user back in the old environment before @command{guix
6267 environment} was invoked. The next garbage collection (@pxref{Invoking
6268 guix gc}) will clean up packages that were installed from within the
6269 environment and are no longer used outside of it.
6271 @vindex GUIX_ENVIRONMENT
6272 @command{guix environment} defines the @env{GUIX_ENVIRONMENT}
6273 variable in the shell it spawns; its value is the file name of the
6274 profile of this environment. This allows users to, say, define a
6275 specific prompt for development environments in their @file{.bashrc}
6276 (@pxref{Bash Startup Files,,, bash, The GNU Bash Reference Manual}):
6279 if [ -n "$GUIX_ENVIRONMENT" ]
6281 export PS1="\u@@\h \w [dev]\$ "
6286 ...@: or to browse the profile:
6289 $ ls "$GUIX_ENVIRONMENT/bin"
6292 Additionally, more than one package may be specified, in which case the
6293 union of the inputs for the given packages are used. For example, the
6294 command below spawns a shell where all of the dependencies of both Guile
6295 and Emacs are available:
6298 guix environment guile emacs
6301 Sometimes an interactive shell session is not desired. An arbitrary
6302 command may be invoked by placing the @code{--} token to separate the
6303 command from the rest of the arguments:
6306 guix environment guile -- make -j4
6309 In other situations, it is more convenient to specify the list of
6310 packages needed in the environment. For example, the following command
6311 runs @command{python} from an environment containing Python@tie{}3 and
6315 guix environment --ad-hoc python-numpy python -- python3
6318 Furthermore, one might want the dependencies of a package and also some
6319 additional packages that are not build-time or runtime dependencies, but
6320 are useful when developing nonetheless. Because of this, the
6321 @option{--ad-hoc} flag is positional. Packages appearing before
6322 @option{--ad-hoc} are interpreted as packages whose dependencies will be
6323 added to the environment. Packages appearing after are interpreted as
6324 packages that will be added to the environment directly. For example,
6325 the following command creates a Guix development environment that
6326 additionally includes Git and strace:
6329 guix environment --pure guix --ad-hoc git strace
6333 Sometimes it is desirable to isolate the environment as much as
6334 possible, for maximal purity and reproducibility. In particular, when
6335 using Guix on a host distro that is not Guix System, it is desirable to
6336 prevent access to @file{/usr/bin} and other system-wide resources from
6337 the development environment. For example, the following command spawns
6338 a Guile REPL in a ``container'' where only the store and the current
6339 working directory are mounted:
6342 guix environment --ad-hoc --container guile -- guile
6346 The @option{--container} option requires Linux-libre 3.19 or newer.
6349 @cindex certificates
6350 Another typical use case for containers is to run security-sensitive
6351 applications such as a web browser. To run Eolie, we must expose and
6352 share some files and directories; we include @code{nss-certs} and expose
6353 @file{/etc/ssl/certs/} for HTTPS authentication; finally we preserve the
6354 @env{DISPLAY} environment variable since containerized graphical
6355 applications won't display without it.
6358 guix environment --preserve='^DISPLAY$' --container --network \
6359 --expose=/etc/machine-id \
6360 --expose=/etc/ssl/certs/ \
6361 --share=$HOME/.local/share/eolie/=$HOME/.local/share/eolie/ \
6362 --ad-hoc eolie nss-certs dbus -- eolie
6365 The available options are summarized below.
6369 Set up the environment and check whether the shell would clobber
6370 environment variables. @xref{Invoking guix shell, @option{--check}},
6373 @item --root=@var{file}
6374 @itemx -r @var{file}
6375 @cindex persistent environment
6376 @cindex garbage collector root, for environments
6377 Make @var{file} a symlink to the profile for this environment, and
6378 register it as a garbage collector root.
6380 This is useful if you want to protect your environment from garbage
6381 collection, to make it ``persistent''.
6383 When this option is omitted, the environment is protected from garbage
6384 collection only for the duration of the @command{guix environment}
6385 session. This means that next time you recreate the same environment,
6386 you could have to rebuild or re-download packages. @xref{Invoking guix
6387 gc}, for more on GC roots.
6389 @item --expression=@var{expr}
6390 @itemx -e @var{expr}
6391 Create an environment for the package or list of packages that
6392 @var{expr} evaluates to.
6394 For example, running:
6397 guix environment -e '(@@ (gnu packages maths) petsc-openmpi)'
6400 starts a shell with the environment for this specific variant of the
6406 guix environment --ad-hoc -e '(@@ (gnu) %base-packages)'
6409 starts a shell with all the base system packages available.
6411 The above commands only use the default output of the given packages.
6412 To select other outputs, two element tuples can be specified:
6415 guix environment --ad-hoc -e '(list (@@ (gnu packages bash) bash) "include")'
6418 @item --load=@var{file}
6419 @itemx -l @var{file}
6420 Create an environment for the package or list of packages that the code
6421 within @var{file} evaluates to.
6423 As an example, @var{file} might contain a definition like this
6424 (@pxref{Defining Packages}):
6427 @verbatiminclude environment-gdb.scm
6430 @item --manifest=@var{file}
6431 @itemx -m @var{file}
6432 Create an environment for the packages contained in the manifest object
6433 returned by the Scheme code in @var{file}. This option can be repeated
6434 several times, in which case the manifests are concatenated.
6436 This is similar to the same-named option in @command{guix package}
6437 (@pxref{profile-manifest, @option{--manifest}}) and uses the same
6440 @xref{shell-export-manifest, @command{guix shell --export-manifest}},
6441 for information on how to ``convert'' command-line options into a
6445 Include all specified packages in the resulting environment, as if an
6446 @i{ad hoc} package were defined with them as inputs. This option is
6447 useful for quickly creating an environment without having to write a
6448 package expression to contain the desired inputs.
6450 For instance, the command:
6453 guix environment --ad-hoc guile guile-sdl -- guile
6456 runs @command{guile} in an environment where Guile and Guile-SDL are
6459 Note that this example implicitly asks for the default output of
6460 @code{guile} and @code{guile-sdl}, but it is possible to ask for a
6461 specific output---e.g., @code{glib:bin} asks for the @code{bin} output
6462 of @code{glib} (@pxref{Packages with Multiple Outputs}).
6464 This option may be composed with the default behavior of @command{guix
6465 environment}. Packages appearing before @option{--ad-hoc} are
6466 interpreted as packages whose dependencies will be added to the
6467 environment, the default behavior. Packages appearing after are
6468 interpreted as packages that will be added to the environment directly.
6470 @item --profile=@var{profile}
6471 @itemx -p @var{profile}
6472 Create an environment containing the packages installed in @var{profile}.
6473 Use @command{guix package} (@pxref{Invoking guix package}) to create
6474 and manage profiles.
6477 Unset existing environment variables when building the new environment, except
6478 those specified with @option{--preserve} (see below). This has the effect of
6479 creating an environment in which search paths only contain package inputs.
6481 @item --preserve=@var{regexp}
6482 @itemx -E @var{regexp}
6483 When used alongside @option{--pure}, preserve the environment variables
6484 matching @var{regexp}---in other words, put them on a ``white list'' of
6485 environment variables that must be preserved. This option can be repeated
6489 guix environment --pure --preserve=^SLURM --ad-hoc openmpi @dots{} \
6493 This example runs @command{mpirun} in a context where the only environment
6494 variables defined are @env{PATH}, environment variables whose name starts
6495 with @samp{SLURM}, as well as the usual ``precious'' variables (@env{HOME},
6498 @item --search-paths
6499 Display the environment variable definitions that make up the
6502 @item --system=@var{system}
6503 @itemx -s @var{system}
6504 Attempt to build for @var{system}---e.g., @code{i686-linux}.
6509 Run @var{command} within an isolated container. The current working
6510 directory outside the container is mapped inside the container.
6511 Additionally, unless overridden with @option{--user}, a dummy home
6512 directory is created that matches the current user's home directory, and
6513 @file{/etc/passwd} is configured accordingly.
6515 The spawned process runs as the current user outside the container. Inside
6516 the container, it has the same UID and GID as the current user, unless
6517 @option{--user} is passed (see below).
6521 For containers, share the network namespace with the host system.
6522 Containers created without this flag only have access to the loopback
6525 @item --link-profile
6527 For containers, link the environment profile to @file{~/.guix-profile}
6528 within the container and set @code{GUIX_ENVIRONMENT} to that.
6529 This is equivalent to making @file{~/.guix-profile} a symlink to the
6530 actual profile within the container.
6531 Linking will fail and abort the environment if the directory already
6532 exists, which will certainly be the case if @command{guix environment}
6533 was invoked in the user's home directory.
6535 Certain packages are configured to look in @file{~/.guix-profile} for
6536 configuration files and data;@footnote{For example, the
6537 @code{fontconfig} package inspects @file{~/.guix-profile/share/fonts}
6538 for additional fonts.} @option{--link-profile} allows these programs to
6539 behave as expected within the environment.
6541 @item --user=@var{user}
6542 @itemx -u @var{user}
6543 For containers, use the username @var{user} in place of the current
6544 user. The generated @file{/etc/passwd} entry within the container will
6545 contain the name @var{user}, the home directory will be
6546 @file{/home/@var{user}}, and no user GECOS data will be copied. Furthermore,
6547 the UID and GID inside the container are 1000. @var{user}
6548 need not exist on the system.
6550 Additionally, any shared or exposed path (see @option{--share} and
6551 @option{--expose} respectively) whose target is within the current user's
6552 home directory will be remapped relative to @file{/home/USER}; this
6553 includes the automatic mapping of the current working directory.
6556 # will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target
6558 guix environment --container --user=foo \
6559 --expose=$HOME/test \
6560 --expose=/tmp/target=$HOME/target
6563 While this will limit the leaking of user identity through home paths
6564 and each of the user fields, this is only one useful component of a
6565 broader privacy/anonymity solution---not one in and of itself.
6568 For containers, the default behavior is to share the current working
6569 directory with the isolated container and immediately change to that
6570 directory within the container. If this is undesirable,
6571 @option{--no-cwd} will cause the current working directory to @emph{not}
6572 be automatically shared and will change to the user's home directory
6573 within the container instead. See also @option{--user}.
6575 @item --expose=@var{source}[=@var{target}]
6576 @itemx --share=@var{source}[=@var{target}]
6577 For containers, @option{--expose} (resp. @option{--share}) exposes the
6578 file system @var{source} from the host system as the read-only
6579 (resp. writable) file system @var{target} within the container. If
6580 @var{target} is not specified, @var{source} is used as the target mount
6581 point in the container.
6583 The example below spawns a Guile REPL in a container in which the user's
6584 home directory is accessible read-only via the @file{/exchange}
6588 guix environment --container --expose=$HOME=/exchange --ad-hoc guile -- guile
6593 @command{guix environment}
6594 also supports all of the common build options that @command{guix
6595 build} supports (@pxref{Common Build Options}) as well as package
6596 transformation options (@pxref{Package Transformation Options}).
6598 @node Invoking guix pack
6599 @section Invoking @command{guix pack}
6601 Occasionally you want to pass software to people who are not (yet!)
6602 lucky enough to be using Guix. You'd tell them to run @command{guix
6603 package -i @var{something}}, but that's not possible in this case. This
6604 is where @command{guix pack} comes in.
6607 If you are looking for ways to exchange binaries among machines that
6608 already run Guix, @pxref{Invoking guix copy}, @ref{Invoking guix
6609 publish}, and @ref{Invoking guix archive}.
6614 @cindex application bundle
6615 @cindex software bundle
6616 The @command{guix pack} command creates a shrink-wrapped @dfn{pack} or
6617 @dfn{software bundle}: it creates a tarball or some other archive
6618 containing the binaries of the software you're interested in, and all
6619 its dependencies. The resulting archive can be used on any machine that
6620 does not have Guix, and people can run the exact same binaries as those
6621 you have with Guix. The pack itself is created in a bit-reproducible
6622 fashion, so anyone can verify that it really contains the build results
6623 that you pretend to be shipping.
6625 For example, to create a bundle containing Guile, Emacs, Geiser, and all
6626 their dependencies, you can run:
6629 $ guix pack guile emacs emacs-geiser
6631 /gnu/store/@dots{}-pack.tar.gz
6634 The result here is a tarball containing a @file{/gnu/store} directory
6635 with all the relevant packages. The resulting tarball contains a
6636 @dfn{profile} with the three packages of interest; the profile is the
6637 same as would be created by @command{guix package -i}. It is this
6638 mechanism that is used to create Guix's own standalone binary tarball
6639 (@pxref{Binary Installation}).
6641 Users of this pack would have to run
6642 @file{/gnu/store/@dots{}-profile/bin/guile} to run Guile, which you may
6643 find inconvenient. To work around it, you can create, say, a
6644 @file{/opt/gnu/bin} symlink to the profile:
6647 guix pack -S /opt/gnu/bin=bin guile emacs emacs-geiser
6651 That way, users can happily type @file{/opt/gnu/bin/guile} and enjoy.
6653 @cindex relocatable binaries, with @command{guix pack}
6654 What if the recipient of your pack does not have root privileges on
6655 their machine, and thus cannot unpack it in the root file system? In
6656 that case, you will want to use the @option{--relocatable} option (see
6657 below). This option produces @dfn{relocatable binaries}, meaning they
6658 they can be placed anywhere in the file system hierarchy: in the example
6659 above, users can unpack your tarball in their home directory and
6660 directly run @file{./opt/gnu/bin/guile}.
6662 @cindex Docker, build an image with guix pack
6663 Alternatively, you can produce a pack in the Docker image format using
6664 the following command:
6667 guix pack -f docker -S /bin=bin guile guile-readline
6671 The result is a tarball that can be passed to the @command{docker load}
6672 command, followed by @code{docker run}:
6675 docker load < @var{file}
6676 docker run -ti guile-guile-readline /bin/guile
6680 where @var{file} is the image returned by @var{guix pack}, and
6681 @code{guile-guile-readline} is its ``image tag''. See the
6682 @uref{https://docs.docker.com/engine/reference/commandline/load/, Docker
6683 documentation} for more information.
6685 @cindex Singularity, build an image with guix pack
6686 @cindex SquashFS, build an image with guix pack
6687 Yet another option is to produce a SquashFS image with the following
6691 guix pack -f squashfs bash guile emacs emacs-geiser
6695 The result is a SquashFS file system image that can either be mounted or
6696 directly be used as a file system container image with the
6697 @uref{https://www.sylabs.io/docs/, Singularity container execution
6698 environment}, using commands like @command{singularity shell} or
6699 @command{singularity exec}.
6701 Several command-line options allow you to customize your pack:
6704 @item --format=@var{format}
6705 @itemx -f @var{format}
6706 Produce a pack in the given @var{format}.
6708 The available formats are:
6712 This is the default format. It produces a tarball containing all the
6713 specified binaries and symlinks.
6716 This produces a tarball that follows the
6717 @uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md,
6718 Docker Image Specification}. The ``repository name'' as it appears in
6719 the output of the @command{docker images} command is computed from
6720 package names passed on the command line or in the manifest file.
6723 This produces a SquashFS image containing all the specified binaries and
6724 symlinks, as well as empty mount points for virtual file systems like
6728 Singularity @emph{requires} you to provide @file{/bin/sh} in the image.
6729 For that reason, @command{guix pack -f squashfs} always implies @code{-S
6730 /bin=bin}. Thus, your @command{guix pack} invocation must always start
6731 with something like:
6734 guix pack -f squashfs bash @dots{}
6737 If you forget the @code{bash} (or similar) package, @command{singularity
6738 run} and @command{singularity exec} will fail with an unhelpful ``no
6739 such file or directory'' message.
6743 This produces a Debian archive (a package with the @samp{.deb} file
6744 extension) containing all the specified binaries and symbolic links,
6745 that can be installed on top of any dpkg-based GNU(/Linux) distribution.
6746 Advanced options can be revealed via the @option{--help-deb-format}
6747 option. They allow embedding control files for more fine-grained
6748 control, such as activating specific triggers or providing a maintainer
6749 configure script to run arbitrary setup code upon installation.
6752 guix pack -f deb -C xz -S /usr/bin/hello=bin/hello hello
6756 Because archives produced with @command{guix pack} contain a collection
6757 of store items and because each @command{dpkg} package must not have
6758 conflicting files, in practice that means you likely won't be able to
6759 install more than one such archive on a given system.
6763 @command{dpkg} will assume ownership of any files contained in the pack
6764 that it does @emph{not} know about. It is unwise to install
6765 Guix-produced @samp{.deb} files on a system where @file{/gnu/store} is
6766 shared by other software, such as a Guix installation or other, non-deb
6772 @cindex relocatable binaries
6775 Produce @dfn{relocatable binaries}---i.e., binaries that can be placed
6776 anywhere in the file system hierarchy and run from there.
6778 When this option is passed once, the resulting binaries require support for
6779 @dfn{user namespaces} in the kernel Linux; when passed
6780 @emph{twice}@footnote{Here's a trick to memorize it: @code{-RR}, which adds
6781 PRoot support, can be thought of as the abbreviation of ``Really
6782 Relocatable''. Neat, isn't it?}, relocatable binaries fall to back to
6783 other techniques if user namespaces are unavailable, and essentially
6784 work anywhere---see below for the implications.
6786 For example, if you create a pack containing Bash with:
6789 guix pack -RR -S /mybin=bin bash
6793 ...@: you can copy that pack to a machine that lacks Guix, and from your
6794 home directory as a normal user, run:
6802 In that shell, if you type @code{ls /gnu/store}, you'll notice that
6803 @file{/gnu/store} shows up and contains all the dependencies of
6804 @code{bash}, even though the machine actually lacks @file{/gnu/store}
6805 altogether! That is probably the simplest way to deploy Guix-built
6806 software on a non-Guix machine.
6809 By default, relocatable binaries rely on the @dfn{user namespace} feature of
6810 the kernel Linux, which allows unprivileged users to mount or change root.
6811 Old versions of Linux did not support it, and some GNU/Linux distributions
6814 To produce relocatable binaries that work even in the absence of user
6815 namespaces, pass @option{--relocatable} or @option{-R} @emph{twice}. In that
6816 case, binaries will try user namespace support and fall back to another
6817 @dfn{execution engine} if user namespaces are not supported. The
6818 following execution engines are supported:
6822 Try user namespaces and fall back to PRoot if user namespaces are not
6823 supported (see below).
6826 Try user namespaces and fall back to Fakechroot if user namespaces are
6827 not supported (see below).
6830 Run the program through user namespaces and abort if they are not
6834 Run through PRoot. The @uref{https://proot-me.github.io/, PRoot} program
6835 provides the necessary
6836 support for file system virtualization. It achieves that by using the
6837 @code{ptrace} system call on the running program. This approach has the
6838 advantage to work without requiring special kernel support, but it incurs
6839 run-time overhead every time a system call is made.
6842 Run through Fakechroot. @uref{https://github.com/dex4er/fakechroot/,
6843 Fakechroot} virtualizes file system accesses by intercepting calls to C
6844 library functions such as @code{open}, @code{stat}, @code{exec}, and so
6845 on. Unlike PRoot, it incurs very little overhead. However, it does not
6846 always work: for example, some file system accesses made from within the
6847 C library are not intercepted, and file system accesses made @i{via}
6848 direct syscalls are not intercepted either, leading to erratic behavior.
6851 @vindex GUIX_EXECUTION_ENGINE
6852 When running a wrapped program, you can explicitly request one of the
6853 execution engines listed above by setting the
6854 @env{GUIX_EXECUTION_ENGINE} environment variable accordingly.
6857 @cindex entry point, for Docker images
6858 @item --entry-point=@var{command}
6859 Use @var{command} as the @dfn{entry point} of the resulting pack, if the pack
6860 format supports it---currently @code{docker} and @code{squashfs} (Singularity)
6861 support it. @var{command} must be relative to the profile contained in the
6864 The entry point specifies the command that tools like @code{docker run} or
6865 @code{singularity run} automatically start by default. For example, you can
6869 guix pack -f docker --entry-point=bin/guile guile
6872 The resulting pack can easily be loaded and @code{docker run} with no extra
6873 arguments will spawn @code{bin/guile}:
6876 docker load -i pack.tar.gz
6877 docker run @var{image-id}
6880 @item --expression=@var{expr}
6881 @itemx -e @var{expr}
6882 Consider the package @var{expr} evaluates to.
6884 This has the same purpose as the same-named option in @command{guix
6885 build} (@pxref{Additional Build Options, @option{--expression} in
6886 @command{guix build}}).
6888 @anchor{pack-manifest}
6889 @item --manifest=@var{file}
6890 @itemx -m @var{file}
6891 Use the packages contained in the manifest object returned by the Scheme
6892 code in @var{file}. This option can be repeated several times, in which
6893 case the manifests are concatenated.
6895 This has a similar purpose as the same-named option in @command{guix
6896 package} (@pxref{profile-manifest, @option{--manifest}}) and uses the
6897 same manifest files. It allows you to define a collection of packages
6898 once and use it both for creating profiles and for creating archives
6899 for use on machines that do not have Guix installed. Note that you can
6900 specify @emph{either} a manifest file @emph{or} a list of packages,
6903 @xref{Writing Manifests}, for information on how to write a manifest.
6904 @xref{shell-export-manifest, @command{guix shell --export-manifest}},
6905 for information on how to ``convert'' command-line options into a
6908 @item --system=@var{system}
6909 @itemx -s @var{system}
6910 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
6911 the system type of the build host.
6913 @item --target=@var{triplet}
6914 @cindex cross-compilation
6915 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
6916 as @code{"aarch64-linux-gnu"} (@pxref{Specifying target triplets, GNU
6917 configuration triplets,, autoconf, Autoconf}).
6919 @item --compression=@var{tool}
6920 @itemx -C @var{tool}
6921 Compress the resulting tarball using @var{tool}---one of @code{gzip},
6922 @code{zstd}, @code{bzip2}, @code{xz}, @code{lzip}, or @code{none} for no
6925 @item --symlink=@var{spec}
6926 @itemx -S @var{spec}
6927 Add the symlinks specified by @var{spec} to the pack. This option can
6928 appear several times.
6930 @var{spec} has the form @code{@var{source}=@var{target}}, where
6931 @var{source} is the symlink that will be created and @var{target} is the
6934 For instance, @code{-S /opt/gnu/bin=bin} creates a @file{/opt/gnu/bin}
6935 symlink pointing to the @file{bin} sub-directory of the profile.
6937 @item --save-provenance
6938 Save provenance information for the packages passed on the command line.
6939 Provenance information includes the URL and commit of the channels in use
6942 Provenance information is saved in the
6943 @file{/gnu/store/@dots{}-profile/manifest} file in the pack, along with the
6944 usual package metadata---the name and version of each package, their
6945 propagated inputs, and so on. It is useful information to the recipient of
6946 the pack, who then knows how the pack was (supposedly) obtained.
6948 This option is not enabled by default because, like timestamps, provenance
6949 information contributes nothing to the build process. In other words, there
6950 is an infinity of channel URLs and commit IDs that can lead to the same pack.
6951 Recording such ``silent'' metadata in the output thus potentially breaks the
6952 source-to-binary bitwise reproducibility property.
6954 @item --root=@var{file}
6955 @itemx -r @var{file}
6956 @cindex garbage collector root, for packs
6957 Make @var{file} a symlink to the resulting pack, and register it as a garbage
6960 @item --localstatedir
6961 @itemx --profile-name=@var{name}
6962 Include the ``local state directory'', @file{/var/guix}, in the resulting
6963 pack, and notably the @file{/var/guix/profiles/per-user/root/@var{name}}
6964 profile---by default @var{name} is @code{guix-profile}, which corresponds to
6965 @file{~root/.guix-profile}.
6967 @file{/var/guix} contains the store database (@pxref{The Store}) as well
6968 as garbage-collector roots (@pxref{Invoking guix gc}). Providing it in
6969 the pack means that the store is ``complete'' and manageable by Guix;
6970 not providing it pack means that the store is ``dead'': items cannot be
6971 added to it or removed from it after extraction of the pack.
6973 One use case for this is the Guix self-contained binary tarball
6974 (@pxref{Binary Installation}).
6978 Print the name of the derivation that builds the pack.
6981 Use the bootstrap binaries to build the pack. This option is only
6982 useful to Guix developers.
6985 In addition, @command{guix pack} supports all the common build options
6986 (@pxref{Common Build Options}) and all the package transformation
6987 options (@pxref{Package Transformation Options}).
6990 @node The GCC toolchain
6991 @section The GCC toolchain
6995 @cindex linker wrapper
6996 @cindex toolchain, for C development
6997 @cindex toolchain, for Fortran development
6999 If you need a complete toolchain for compiling and linking C or C++
7000 source code, use the @code{gcc-toolchain} package. This package
7001 provides a complete GCC toolchain for C/C++ development, including GCC
7002 itself, the GNU C Library (headers and binaries, plus debugging symbols
7003 in the @code{debug} output), Binutils, and a linker wrapper.
7005 The wrapper's purpose is to inspect the @code{-L} and @code{-l} switches
7006 passed to the linker, add corresponding @code{-rpath} arguments, and
7007 invoke the actual linker with this new set of arguments. You can instruct the
7008 wrapper to refuse to link against libraries not in the store by setting the
7009 @env{GUIX_LD_WRAPPER_ALLOW_IMPURITIES} environment variable to @code{no}.
7011 The package @code{gfortran-toolchain} provides a complete GCC toolchain
7012 for Fortran development. For other languages, please use
7013 @samp{guix search gcc toolchain} (@pxref{guix-search,, Invoking guix package}).
7016 @node Invoking guix git authenticate
7017 @section Invoking @command{guix git authenticate}
7019 The @command{guix git authenticate} command authenticates a Git checkout
7020 following the same rule as for channels (@pxref{channel-authentication,
7021 channel authentication}). That is, starting from a given commit, it
7022 ensures that all subsequent commits are signed by an OpenPGP key whose
7023 fingerprint appears in the @file{.guix-authorizations} file of its
7026 You will find this command useful if you maintain a channel. But in
7027 fact, this authentication mechanism is useful in a broader context, so
7028 you might want to use it for Git repositories that have nothing to do
7031 The general syntax is:
7034 guix git authenticate @var{commit} @var{signer} [@var{options}@dots{}]
7037 By default, this command authenticates the Git checkout in the current
7038 directory; it outputs nothing and exits with exit code zero on success
7039 and non-zero on failure. @var{commit} above denotes the first commit
7040 where authentication takes place, and @var{signer} is the OpenPGP
7041 fingerprint of public key used to sign @var{commit}. Together, they
7042 form a ``channel introduction'' (@pxref{channel-authentication, channel
7043 introduction}). The options below allow you to fine-tune the process.
7046 @item --repository=@var{directory}
7047 @itemx -r @var{directory}
7048 Open the Git repository in @var{directory} instead of the current
7051 @item --keyring=@var{reference}
7052 @itemx -k @var{reference}
7053 Load OpenPGP keyring from @var{reference}, the reference of a branch
7054 such as @code{origin/keyring} or @code{my-keyring}. The branch must
7055 contain OpenPGP public keys in @file{.key} files, either in binary form
7056 or ``ASCII-armored''. By default the keyring is loaded from the branch
7057 named @code{keyring}.
7060 Display commit signing statistics upon completion.
7062 @item --cache-key=@var{key}
7063 Previously-authenticated commits are cached in a file under
7064 @file{~/.cache/guix/authentication}. This option forces the cache to be
7065 stored in file @var{key} in that directory.
7067 @item --historical-authorizations=@var{file}
7068 By default, any commit whose parent commit(s) lack the
7069 @file{.guix-authorizations} file is considered inauthentic. In
7070 contrast, this option considers the authorizations in @var{file} for any
7071 commit that lacks @file{.guix-authorizations}. The format of @var{file}
7072 is the same as that of @file{.guix-authorizations}
7073 (@pxref{channel-authorizations, @file{.guix-authorizations} format}).
7077 @c *********************************************************************
7078 @node Programming Interface
7079 @chapter Programming Interface
7081 GNU Guix provides several Scheme programming interfaces (APIs) to
7082 define, build, and query packages. The first interface allows users to
7083 write high-level package definitions. These definitions refer to
7084 familiar packaging concepts, such as the name and version of a package,
7085 its build system, and its dependencies. These definitions can then be
7086 turned into concrete build actions.
7088 Build actions are performed by the Guix daemon, on behalf of users. In a
7089 standard setup, the daemon has write access to the store---the
7090 @file{/gnu/store} directory---whereas users do not. The recommended
7091 setup also has the daemon perform builds in chroots, under specific
7092 build users, to minimize interference with the rest of the system.
7095 Lower-level APIs are available to interact with the daemon and the
7096 store. To instruct the daemon to perform a build action, users actually
7097 provide it with a @dfn{derivation}. A derivation is a low-level
7098 representation of the build actions to be taken, and the environment in
7099 which they should occur---derivations are to package definitions what
7100 assembly is to C programs. The term ``derivation'' comes from the fact
7101 that build results @emph{derive} from them.
7103 This chapter describes all these APIs in turn, starting from high-level
7104 package definitions.
7107 * Package Modules:: Packages from the programmer's viewpoint.
7108 * Defining Packages:: Defining new packages.
7109 * Defining Package Variants:: Customizing packages.
7110 * Writing Manifests:: The bill of materials of your environment.
7111 * Build Systems:: Specifying how packages are built.
7112 * Build Phases:: Phases of the build process of a package.
7113 * Build Utilities:: Helpers for your package definitions and more.
7114 * Search Paths:: Declaring search path environment variables.
7115 * The Store:: Manipulating the package store.
7116 * Derivations:: Low-level interface to package derivations.
7117 * The Store Monad:: Purely functional interface to the store.
7118 * G-Expressions:: Manipulating build expressions.
7119 * Invoking guix repl:: Programming Guix in Guile
7120 * Using Guix Interactively:: Fine-grain interaction at the REPL.
7123 @node Package Modules
7124 @section Package Modules
7126 From a programming viewpoint, the package definitions of the
7127 GNU distribution are provided by Guile modules in the @code{(gnu packages
7128 @dots{})} name space@footnote{Note that packages under the @code{(gnu
7129 packages @dots{})} module name space are not necessarily ``GNU
7130 packages''. This module naming scheme follows the usual Guile module
7131 naming convention: @code{gnu} means that these modules are distributed
7132 as part of the GNU system, and @code{packages} identifies modules that
7133 define packages.} (@pxref{Modules, Guile modules,, guile, GNU Guile
7134 Reference Manual}). For instance, the @code{(gnu packages emacs)}
7135 module exports a variable named @code{emacs}, which is bound to a
7136 @code{<package>} object (@pxref{Defining Packages}).
7138 The @code{(gnu packages @dots{})} module name space is
7139 automatically scanned for packages by the command-line tools. For
7140 instance, when running @code{guix install emacs}, all the @code{(gnu
7141 packages @dots{})} modules are scanned until one that exports a package
7142 object whose name is @code{emacs} is found. This package search
7143 facility is implemented in the @code{(gnu packages)} module.
7145 @cindex customization, of packages
7146 @cindex package module search path
7147 Users can store package definitions in modules with different
7148 names---e.g., @code{(my-packages emacs)}@footnote{Note that the file
7149 name and module name must match. For instance, the @code{(my-packages
7150 emacs)} module must be stored in a @file{my-packages/emacs.scm} file
7151 relative to the load path specified with @option{--load-path} or
7152 @env{GUIX_PACKAGE_PATH}. @xref{Modules and the File System,,,
7153 guile, GNU Guile Reference Manual}, for details.}. There are two ways to make
7154 these package definitions visible to the user interfaces:
7158 By adding the directory containing your package modules to the search path
7159 with the @code{-L} flag of @command{guix package} and other commands
7160 (@pxref{Common Build Options}), or by setting the @env{GUIX_PACKAGE_PATH}
7161 environment variable described below.
7164 By defining a @dfn{channel} and configuring @command{guix pull} so that it
7165 pulls from it. A channel is essentially a Git repository containing package
7166 modules. @xref{Channels}, for more information on how to define and use
7170 @env{GUIX_PACKAGE_PATH} works similarly to other search path variables:
7172 @defvr {Environment Variable} GUIX_PACKAGE_PATH
7173 This is a colon-separated list of directories to search for additional
7174 package modules. Directories listed in this variable take precedence
7175 over the own modules of the distribution.
7178 The distribution is fully @dfn{bootstrapped} and @dfn{self-contained}:
7179 each package is built based solely on other packages in the
7180 distribution. The root of this dependency graph is a small set of
7181 @dfn{bootstrap binaries}, provided by the @code{(gnu packages
7182 bootstrap)} module. For more information on bootstrapping,
7183 @pxref{Bootstrapping}.
7185 @node Defining Packages
7186 @section Defining Packages
7188 The high-level interface to package definitions is implemented in the
7189 @code{(guix packages)} and @code{(guix build-system)} modules. As an
7190 example, the package definition, or @dfn{recipe}, for the GNU Hello
7191 package looks like this:
7194 (define-module (gnu packages hello)
7195 #:use-module (guix packages)
7196 #:use-module (guix download)
7197 #:use-module (guix build-system gnu)
7198 #:use-module (guix licenses)
7199 #:use-module (gnu packages gawk))
7201 (define-public hello
7207 (uri (string-append "mirror://gnu/hello/hello-" version
7211 "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"))))
7212 (build-system gnu-build-system)
7213 (arguments '(#:configure-flags '("--enable-silent-rules")))
7214 (inputs (list gawk))
7215 (synopsis "Hello, GNU world: An example GNU package")
7216 (description "Guess what GNU Hello prints!")
7217 (home-page "https://www.gnu.org/software/hello/")
7222 Without being a Scheme expert, the reader may have guessed the meaning
7223 of the various fields here. This expression binds the variable
7224 @code{hello} to a @code{<package>} object, which is essentially a record
7225 (@pxref{SRFI-9, Scheme records,, guile, GNU Guile Reference Manual}).
7226 This package object can be inspected using procedures found in the
7227 @code{(guix packages)} module; for instance, @code{(package-name hello)}
7228 returns---surprise!---@code{"hello"}.
7230 With luck, you may be able to import part or all of the definition of
7231 the package you are interested in from another repository, using the
7232 @code{guix import} command (@pxref{Invoking guix import}).
7234 In the example above, @code{hello} is defined in a module of its own,
7235 @code{(gnu packages hello)}. Technically, this is not strictly
7236 necessary, but it is convenient to do so: all the packages defined in
7237 modules under @code{(gnu packages @dots{})} are automatically known to
7238 the command-line tools (@pxref{Package Modules}).
7240 There are a few points worth noting in the above package definition:
7244 The @code{source} field of the package is an @code{<origin>} object
7245 (@pxref{origin Reference}, for the complete reference).
7246 Here, the @code{url-fetch} method from @code{(guix download)} is used,
7247 meaning that the source is a file to be downloaded over FTP or HTTP.
7249 The @code{mirror://gnu} prefix instructs @code{url-fetch} to use one of
7250 the GNU mirrors defined in @code{(guix download)}.
7252 The @code{sha256} field specifies the expected SHA256 hash of the file
7253 being downloaded. It is mandatory, and allows Guix to check the
7254 integrity of the file. The @code{(base32 @dots{})} form introduces the
7255 base32 representation of the hash. You can obtain this information with
7256 @code{guix download} (@pxref{Invoking guix download}) and @code{guix
7257 hash} (@pxref{Invoking guix hash}).
7260 When needed, the @code{origin} form can also have a @code{patches} field
7261 listing patches to be applied, and a @code{snippet} field giving a
7262 Scheme expression to modify the source code.
7265 @cindex GNU Build System
7266 The @code{build-system} field specifies the procedure to build the
7267 package (@pxref{Build Systems}). Here, @code{gnu-build-system}
7268 represents the familiar GNU Build System, where packages may be
7269 configured, built, and installed with the usual @code{./configure &&
7270 make && make check && make install} command sequence.
7272 When you start packaging non-trivial software, you may need tools to
7273 manipulate those build phases, manipulate files, and so on. @xref{Build
7274 Utilities}, for more on this.
7277 The @code{arguments} field specifies options for the build system
7278 (@pxref{Build Systems}). Here it is interpreted by
7279 @code{gnu-build-system} as a request run @file{configure} with the
7280 @option{--enable-silent-rules} flag.
7286 @cindex backquote (quasiquote)
7289 @cindex comma (unquote)
7292 What about these quote (@code{'}) characters? They are Scheme syntax to
7293 introduce a literal list; @code{'} is synonymous with @code{quote}.
7294 Sometimes you'll also see @code{`} (a backquote, synonymous with
7295 @code{quasiquote}) and @code{,} (a comma, synonymous with @code{unquote}).
7296 @xref{Expression Syntax, quoting,, guile, GNU Guile Reference Manual},
7297 for details. Here the value of the @code{arguments} field is a list of
7298 arguments passed to the build system down the road, as with @code{apply}
7299 (@pxref{Fly Evaluation, @code{apply},, guile, GNU Guile Reference
7302 The hash-colon (@code{#:}) sequence defines a Scheme @dfn{keyword}
7303 (@pxref{Keywords,,, guile, GNU Guile Reference Manual}), and
7304 @code{#:configure-flags} is a keyword used to pass a keyword argument
7305 to the build system (@pxref{Coding With Keywords,,, guile, GNU Guile
7309 The @code{inputs} field specifies inputs to the build process---i.e.,
7310 build-time or run-time dependencies of the package. Here, we add
7311 an input, a reference to the @code{gawk}
7312 variable; @code{gawk} is itself bound to a @code{<package>} object.
7314 Note that GCC, Coreutils, Bash, and other essential tools do not need to
7315 be specified as inputs here. Instead, @code{gnu-build-system} takes care
7316 of ensuring that they are present (@pxref{Build Systems}).
7318 However, any other dependencies need to be specified in the
7319 @code{inputs} field. Any dependency not specified here will simply be
7320 unavailable to the build process, possibly leading to a build failure.
7323 @xref{package Reference}, for a full description of possible fields.
7325 Once a package definition is in place, the
7326 package may actually be built using the @code{guix build} command-line
7327 tool (@pxref{Invoking guix build}), troubleshooting any build failures
7328 you encounter (@pxref{Debugging Build Failures}). You can easily jump back to the
7329 package definition using the @command{guix edit} command
7330 (@pxref{Invoking guix edit}).
7331 @xref{Packaging Guidelines}, for
7332 more information on how to test package definitions, and
7333 @ref{Invoking guix lint}, for information on how to check a definition
7334 for style conformance.
7335 @vindex GUIX_PACKAGE_PATH
7336 Lastly, @pxref{Channels}, for information
7337 on how to extend the distribution by adding your own package definitions
7340 Finally, updating the package definition to a new upstream version
7341 can be partly automated by the @command{guix refresh} command
7342 (@pxref{Invoking guix refresh}).
7344 Behind the scenes, a derivation corresponding to the @code{<package>}
7345 object is first computed by the @code{package-derivation} procedure.
7346 That derivation is stored in a @file{.drv} file under @file{/gnu/store}.
7347 The build actions it prescribes may then be realized by using the
7348 @code{build-derivations} procedure (@pxref{The Store}).
7350 @deffn {Scheme Procedure} package-derivation @var{store} @var{package} [@var{system}]
7351 Return the @code{<derivation>} object of @var{package} for @var{system}
7352 (@pxref{Derivations}).
7354 @var{package} must be a valid @code{<package>} object, and @var{system}
7355 must be a string denoting the target system type---e.g.,
7356 @code{"x86_64-linux"} for an x86_64 Linux-based GNU system. @var{store}
7357 must be a connection to the daemon, which operates on the store
7358 (@pxref{The Store}).
7362 @cindex cross-compilation
7363 Similarly, it is possible to compute a derivation that cross-builds a
7364 package for some other system:
7366 @deffn {Scheme Procedure} package-cross-derivation @var{store} @
7367 @var{package} @var{target} [@var{system}]
7368 Return the @code{<derivation>} object of @var{package} cross-built from
7369 @var{system} to @var{target}.
7371 @var{target} must be a valid GNU triplet denoting the target hardware
7372 and operating system, such as @code{"aarch64-linux-gnu"}
7373 (@pxref{Specifying Target Triplets,,, autoconf, Autoconf}).
7376 Once you have package definitions, you can easily define @emph{variants}
7377 of those packages. @xref{Defining Package Variants}, for more on that.
7380 * package Reference:: The package data type.
7381 * origin Reference:: The origin data type.
7385 @node package Reference
7386 @subsection @code{package} Reference
7388 This section summarizes all the options available in @code{package}
7389 declarations (@pxref{Defining Packages}).
7391 @deftp {Data Type} package
7392 This is the data type representing a package recipe.
7396 The name of the package, as a string.
7398 @item @code{version}
7399 The version of the package, as a string. @xref{Version Numbers}, for
7403 An object telling how the source code for the package should be
7404 acquired. Most of the time, this is an @code{origin} object, which
7405 denotes a file fetched from the Internet (@pxref{origin Reference}). It
7406 can also be any other ``file-like'' object such as a @code{local-file},
7407 which denotes a file from the local file system (@pxref{G-Expressions,
7408 @code{local-file}}).
7410 @item @code{build-system}
7411 The build system that should be used to build the package (@pxref{Build
7414 @item @code{arguments} (default: @code{'()})
7415 The arguments that should be passed to the build system (@pxref{Build
7416 Systems}). This is a list, typically containing sequential
7417 keyword-value pairs, as in this example:
7422 ;; several fields omitted
7424 (list #:tests? #f ;skip tests
7425 #:make-flags #~'("VERBOSE=1") ;pass flags to 'make'
7426 #:configure-flags #~'("--enable-frobbing"))))
7429 The exact set of supported keywords depends on the build system
7430 (@pxref{Build Systems}), but you will find that almost all of them honor
7431 @code{#:configure-flags}, @code{#:make-flags}, @code{#:tests?}, and
7432 @code{#:phases}. The @code{#:phases} keyword in particular lets you
7433 modify the set of build phases for your package (@pxref{Build Phases}).
7435 @item @code{inputs} (default: @code{'()})
7436 @itemx @code{native-inputs} (default: @code{'()})
7437 @itemx @code{propagated-inputs} (default: @code{'()})
7438 @cindex inputs, of packages
7439 These fields list dependencies of the package. Each element of these
7440 lists is either a package, origin, or other ``file-like object''
7441 (@pxref{G-Expressions}); to specify the output of that file-like object
7442 that should be used, pass a two-element list where the second element is
7443 the output (@pxref{Packages with Multiple Outputs}, for more on package
7444 outputs). For example, the list below specifies three inputs:
7447 (list libffi libunistring
7448 `(,glib "bin")) ;the "bin" output of GLib
7451 In the example above, the @code{"out"} output of @code{libffi} and
7452 @code{libunistring} is used.
7454 @quotation Compatibility Note
7455 Until version 1.3.0, input lists were a list of tuples,
7456 where each tuple has a label for the input (a string) as its
7457 first element, a package, origin, or derivation as its second element,
7458 and optionally the name of the output thereof that should be used, which
7459 defaults to @code{"out"}. For example, the list below is equivalent to
7460 the one above, but using the @dfn{old input style}:
7463 ;; Old input style (deprecated).
7464 `(("libffi" ,libffi)
7465 ("libunistring" ,libunistring)
7466 ("glib:bin" ,glib "bin")) ;the "bin" output of GLib
7469 This style is now deprecated; it is still supported but support will be
7470 removed in a future version. It should not be used for new package
7471 definitions. @xref{Invoking guix style}, on how to migrate to the new
7475 @cindex cross compilation, package dependencies
7476 The distinction between @code{native-inputs} and @code{inputs} is
7477 necessary when considering cross-compilation. When cross-compiling,
7478 dependencies listed in @code{inputs} are built for the @emph{target}
7479 architecture; conversely, dependencies listed in @code{native-inputs}
7480 are built for the architecture of the @emph{build} machine.
7482 @code{native-inputs} is typically used to list tools needed at
7483 build time, but not at run time, such as Autoconf, Automake, pkg-config,
7484 Gettext, or Bison. @command{guix lint} can report likely mistakes in
7485 this area (@pxref{Invoking guix lint}).
7487 @anchor{package-propagated-inputs}
7488 Lastly, @code{propagated-inputs} is similar to @code{inputs}, but the
7489 specified packages will be automatically installed to profiles
7490 (@pxref{Features, the role of profiles in Guix}) alongside the package
7491 they belong to (@pxref{package-cmd-propagated-inputs, @command{guix
7492 package}}, for information on how @command{guix package} deals with
7495 For example this is necessary when packaging a C/C++ library that needs
7496 headers of another library to compile, or when a pkg-config file refers
7497 to another one @i{via} its @code{Requires} field.
7499 Another example where @code{propagated-inputs} is useful is for languages
7500 that lack a facility to record the run-time search path akin to the
7501 @code{RUNPATH} of ELF files; this includes Guile, Python, Perl, and
7502 more. When packaging libraries written in those languages, ensure they
7503 can find library code they depend on at run time by listing run-time
7504 dependencies in @code{propagated-inputs} rather than @code{inputs}.
7506 @item @code{outputs} (default: @code{'("out")})
7507 The list of output names of the package. @xref{Packages with Multiple
7508 Outputs}, for typical uses of additional outputs.
7510 @item @code{native-search-paths} (default: @code{'()})
7511 @itemx @code{search-paths} (default: @code{'()})
7512 A list of @code{search-path-specification} objects describing
7513 search-path environment variables honored by the package. @xref{Search
7514 Paths}, for more on search path specifications.
7516 As for inputs, the distinction between @code{native-search-paths} and
7517 @code{search-paths} only matters when cross-compiling. In a
7518 cross-compilation context, @code{native-search-paths} applies
7519 exclusively to native inputs whereas @code{search-paths} applies only to
7522 Packages such as cross-compilers care about target inputs---for
7523 instance, our (modified) GCC cross-compiler has
7524 @env{CROSS_C_INCLUDE_PATH} in @code{search-paths}, which allows it to
7525 pick @file{.h} files for the target system and @emph{not} those of
7526 native inputs. For the majority of packages though, only
7527 @code{native-search-paths} makes sense.
7529 @item @code{replacement} (default: @code{#f})
7530 This must be either @code{#f} or a package object that will be used as a
7531 @dfn{replacement} for this package. @xref{Security Updates, grafts},
7534 @item @code{synopsis}
7535 A one-line description of the package.
7537 @item @code{description}
7538 A more elaborate description of the package, as a string in Texinfo
7541 @item @code{license}
7542 @cindex license, of packages
7543 The license of the package; a value from @code{(guix licenses)},
7544 or a list of such values.
7546 @item @code{home-page}
7547 The URL to the home-page of the package, as a string.
7549 @item @code{supported-systems} (default: @code{%supported-systems})
7550 The list of systems supported by the package, as strings of the form
7551 @code{architecture-kernel}, for example @code{"x86_64-linux"}.
7553 @item @code{location} (default: source location of the @code{package} form)
7554 The source location of the package. It is useful to override this when
7555 inheriting from another package, in which case this field is not
7556 automatically corrected.
7560 @deffn {Scheme Syntax} this-package
7561 When used in the @emph{lexical scope} of a package field definition, this
7562 identifier resolves to the package being defined.
7564 The example below shows how to add a package as a native input of itself when
7572 ;; When cross-compiled, Guile, for example, depends on
7573 ;; a native version of itself. Add it here.
7574 (native-inputs (if (%current-target-system)
7579 It is an error to refer to @code{this-package} outside a package definition.
7582 The following helper procedures are provided to help deal with package
7585 @deffn {Scheme Procedure} lookup-package-input @var{package} @var{name}
7586 @deffnx {Scheme Procedure} lookup-package-native-input @var{package} @var{name}
7587 @deffnx {Scheme Procedure} lookup-package-propagated-input @var{package} @var{name}
7588 @deffnx {Scheme Procedure} lookup-package-direct-input @var{package} @var{name}
7589 Look up @var{name} among @var{package}'s inputs (or native, propagated,
7590 or direct inputs). Return it if found, @code{#f} otherwise.
7592 @var{name} is the name of a package depended on. Here's how you might
7596 (use-modules (guix packages) (gnu packages base))
7598 (lookup-package-direct-input coreutils "gmp")
7599 @result{} #<package gmp@@6.2.1 @dots{}>
7602 In this example we obtain the @code{gmp} package that is among the
7603 direct inputs of @code{coreutils}.
7606 @cindex development inputs, of a package
7607 @cindex implicit inputs, of a package
7608 Sometimes you will want to obtain the list of inputs needed to
7609 @emph{develop} a package---all the inputs that are visible when the
7610 package is compiled. This is what the @code{package-development-inputs}
7613 @deffn {Scheme Procedure} package-development-inputs @var{package} @
7614 [@var{system}] [#:target #f]
7615 Return the list of inputs required by @var{package} for development
7616 purposes on @var{system}. When @var{target} is true, return the inputs
7617 needed to cross-compile @var{package} from @var{system} to
7618 @var{triplet}, where @var{triplet} is a triplet such as
7619 @code{"aarch64-linux-gnu"}.
7621 Note that the result includes both explicit inputs and implicit
7622 inputs---inputs automatically added by the build system (@pxref{Build
7623 Systems}). Let us take the @code{hello} package to illustrate that:
7626 (use-modules (gnu packages base) (guix packages))
7629 @result{} #<package hello@@2.10 gnu/packages/base.scm:79 7f585d4f6790>
7631 (package-direct-inputs hello)
7634 (package-development-inputs hello)
7635 @result{} (("source" @dots{}) ("tar" #<package tar@@1.32 @dots{}>) @dots{})
7638 In this example, @code{package-direct-inputs} returns the empty list,
7639 because @code{hello} has zero explicit dependencies. Conversely,
7640 @code{package-development-inputs} includes inputs implicitly added by
7641 @code{gnu-build-system} that are required to build @code{hello}: tar,
7642 gzip, GCC, libc, Bash, and more. To visualize it, @command{guix graph
7643 hello} would show you explicit inputs, whereas @command{guix graph -t
7644 bag hello} would include implicit inputs (@pxref{Invoking guix graph}).
7647 Because packages are regular Scheme objects that capture a complete
7648 dependency graph and associated build procedures, it is often useful to
7649 write procedures that take a package and return a modified version
7650 thereof according to some parameters. Below are a few examples.
7652 @cindex tool chain, choosing a package's tool chain
7653 @deffn {Scheme Procedure} package-with-c-toolchain @var{package} @var{toolchain}
7654 Return a variant of @var{package} that uses @var{toolchain} instead of
7655 the default GNU C/C++ toolchain. @var{toolchain} must be a list of
7656 inputs (label/package tuples) providing equivalent functionality, such
7657 as the @code{gcc-toolchain} package.
7659 The example below returns a variant of the @code{hello} package built
7660 with GCC@tie{}10.x and the rest of the GNU tool chain (Binutils and the
7661 GNU C Library) instead of the default tool chain:
7664 (let ((toolchain (specification->package "gcc-toolchain@@10")))
7665 (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
7668 The build tool chain is part of the @dfn{implicit inputs} of
7669 packages---it's usually not listed as part of the various ``inputs''
7670 fields and is instead pulled in by the build system. Consequently, this
7671 procedure works by changing the build system of @var{package} so that it
7672 pulls in @var{toolchain} instead of the defaults. @ref{Build Systems},
7673 for more on build systems.
7676 @node origin Reference
7677 @subsection @code{origin} Reference
7679 This section documents @dfn{origins}. An @code{origin} declaration
7680 specifies data that must be ``produced''---downloaded, usually---and
7681 whose content hash is known in advance. Origins are primarily used to
7682 represent the source code of packages (@pxref{Defining Packages}). For
7683 that reason, the @code{origin} form allows you to declare patches to
7684 apply to the original source code as well as code snippets to modify it.
7686 @deftp {Data Type} origin
7687 This is the data type representing a source code origin.
7691 An object containing the URI of the source. The object type depends on
7692 the @code{method} (see below). For example, when using the
7693 @var{url-fetch} method of @code{(guix download)}, the valid @code{uri}
7694 values are: a URL represented as a string, or a list thereof.
7696 @cindex fixed-output derivations, for download
7698 A monadic procedure that handles the given URI@. The procedure must
7699 accept at least three arguments: the value of the @code{uri} field and
7700 the hash algorithm and hash value specified by the @code{hash} field.
7701 It must return a store item or a derivation in the store monad
7702 (@pxref{The Store Monad}); most methods return a fixed-output derivation
7703 (@pxref{Derivations}).
7705 Commonly used methods include @code{url-fetch}, which fetches data from
7706 a URL, and @code{git-fetch}, which fetches data from a Git repository
7710 A bytevector containing the SHA-256 hash of the source. This is
7711 equivalent to providing a @code{content-hash} SHA256 object in the
7712 @code{hash} field described below.
7715 The @code{content-hash} object of the source---see below for how to use
7716 @code{content-hash}.
7718 You can obtain this information using @code{guix download}
7719 (@pxref{Invoking guix download}) or @code{guix hash} (@pxref{Invoking
7722 @item @code{file-name} (default: @code{#f})
7723 The file name under which the source code should be saved. When this is
7724 @code{#f}, a sensible default value will be used in most cases. In case
7725 the source is fetched from a URL, the file name from the URL will be
7726 used. For version control checkouts, it is recommended to provide the
7727 file name explicitly because the default is not very descriptive.
7729 @item @code{patches} (default: @code{'()})
7730 A list of file names, origins, or file-like objects (@pxref{G-Expressions,
7731 file-like objects}) pointing to patches to be applied to the source.
7733 This list of patches must be unconditional. In particular, it cannot
7734 depend on the value of @code{%current-system} or
7735 @code{%current-target-system}.
7737 @item @code{snippet} (default: @code{#f})
7738 A G-expression (@pxref{G-Expressions}) or S-expression that will be run
7739 in the source directory. This is a convenient way to modify the source,
7740 sometimes more convenient than a patch.
7742 @item @code{patch-flags} (default: @code{'("-p1")})
7743 A list of command-line flags that should be passed to the @code{patch}
7746 @item @code{patch-inputs} (default: @code{#f})
7747 Input packages or derivations to the patching process. When this is
7748 @code{#f}, the usual set of inputs necessary for patching are provided,
7749 such as GNU@tie{}Patch.
7751 @item @code{modules} (default: @code{'()})
7752 A list of Guile modules that should be loaded during the patching
7753 process and while running the code in the @code{snippet} field.
7755 @item @code{patch-guile} (default: @code{#f})
7756 The Guile package that should be used in the patching process. When
7757 this is @code{#f}, a sensible default is used.
7761 @deftp {Data Type} content-hash @var{value} [@var{algorithm}]
7762 Construct a content hash object for the given @var{algorithm}, and with
7763 @var{value} as its hash value. When @var{algorithm} is omitted, assume
7764 it is @code{sha256}.
7766 @var{value} can be a literal string, in which case it is base32-decoded,
7767 or it can be a bytevector.
7769 The following forms are all equivalent:
7772 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj")
7773 (content-hash "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"
7775 (content-hash (base32
7776 "05zxkyz9bv3j9h0xyid1rhvh3klhsmrpkf3bcs6frvlgyr2gwilj"))
7777 (content-hash (base64 "kkb+RPaP7uyMZmu4eXPVkM4BN8yhRd8BTHLslb6f/Rc=")
7781 Technically, @code{content-hash} is currently implemented as a macro.
7782 It performs sanity checks at macro-expansion time, when possible, such
7783 as ensuring that @var{value} has the right size for @var{algorithm}.
7786 As we have seen above, how exactly the data an origin refers to is
7787 retrieved is determined by its @code{method} field. The @code{(guix
7788 download)} module provides the most common method, @code{url-fetch},
7791 @deffn {Scheme Procedure} url-fetch @var{url} @var{hash-algo} @var{hash} @
7792 [name] [#:executable? #f]
7793 Return a fixed-output derivation that fetches data from @var{url} (a
7794 string, or a list of strings denoting alternate URLs), which is expected
7795 to have hash @var{hash} of type @var{hash-algo} (a symbol). By default,
7796 the file name is the base name of URL; optionally, @var{name} can
7797 specify a different file name. When @var{executable?} is true, make the
7798 downloaded file executable.
7800 When one of the URL starts with @code{mirror://}, then its host part is
7801 interpreted as the name of a mirror scheme, taken from @file{%mirror-file}.
7803 Alternatively, when URL starts with @code{file://}, return the
7804 corresponding file name in the store.
7807 Likewise, the @code{(guix git-download)} module defines the
7808 @code{git-fetch} origin method, which fetches data from a Git version
7809 control repository, and the @code{git-reference} data type to describe
7810 the repository and revision to fetch.
7812 @deffn {Scheme Procedure} git-fetch @var{ref} @var{hash-algo} @var{hash}
7813 Return a fixed-output derivation that fetches @var{ref}, a
7814 @code{<git-reference>} object. The output is expected to have recursive
7815 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7816 the file name, or a generic name if @code{#f}.
7819 @deftp {Data Type} git-reference
7820 This data type represents a Git reference for @code{git-fetch} to
7825 The URL of the Git repository to clone.
7828 This string denotes either the commit to fetch (a hexadecimal string),
7829 or the tag to fetch. You can also use a ``short'' commit ID or a
7830 @command{git describe} style identifier such as
7831 @code{v1.0.1-10-g58d7909c97}.
7833 @item @code{recursive?} (default: @code{#f})
7834 This Boolean indicates whether to recursively fetch Git sub-modules.
7837 The example below denotes the @code{v2.10} tag of the GNU@tie{}Hello
7842 (url "https://git.savannah.gnu.org/git/hello.git")
7846 This is equivalent to the reference below, which explicitly names the
7851 (url "https://git.savannah.gnu.org/git/hello.git")
7852 (commit "dc7dc56a00e48fe6f231a58f6537139fe2908fb9"))
7856 For Mercurial repositories, the module @code{(guix hg-download)} defines
7857 the @code{hg-fetch} origin method and @code{hg-reference} data type for
7858 support of the Mercurial version control system.
7860 @deffn {Scheme Procedure} hg-fetch @var{ref} @var{hash-algo} @var{hash} @
7862 Return a fixed-output derivation that fetches @var{ref}, a
7863 @code{<hg-reference>} object. The output is expected to have recursive
7864 hash @var{hash} of type @var{hash-algo} (a symbol). Use @var{name} as
7865 the file name, or a generic name if @code{#false}.
7868 @node Defining Package Variants
7869 @section Defining Package Variants
7871 @cindex customizing packages
7872 @cindex variants, of packages
7873 One of the nice things with Guix is that, given a package definition,
7874 you can easily @emph{derive} variants of that package---for a different
7875 upstream version, with different dependencies, different compilation
7876 options, and so on. Some of these custom packages can be defined
7877 straight from the command line (@pxref{Package Transformation Options}).
7878 This section describes how to define package variants in code. This can
7879 be useful in ``manifests'' (@pxref{Writing Manifests})
7880 and in your own package collection
7881 (@pxref{Creating a Channel}), among others!
7883 @cindex inherit, for package definitions
7884 As discussed earlier, packages are first-class objects in the Scheme
7885 language. The @code{(guix packages)} module provides the @code{package}
7886 construct to define new package objects (@pxref{package Reference}).
7887 The easiest way to define a package variant is using the @code{inherit}
7888 keyword together with @code{package}. This allows you to inherit from a
7889 package definition while overriding the fields you want.
7891 For example, given the @code{hello} variable, which contains a
7892 definition for the current version of GNU@tie{}Hello, here's how you
7893 would define a variant for version 2.2 (released in 2006, it's
7897 (use-modules (gnu packages base)) ;for 'hello'
7905 (uri (string-append "mirror://gnu/hello/hello-" version
7909 "0lappv4slgb5spyqbh6yl5r013zv72yqg2pcl30mginf3wdqd8k9"))))))
7912 The example above corresponds to what the @option{--with-source} package
7913 transformation option does. Essentially @code{hello-2.2} preserves all
7914 the fields of @code{hello}, except @code{version} and @code{source},
7915 which it overrides. Note that the original @code{hello} variable is
7916 still there, in the @code{(gnu packages base)} module, unchanged. When
7917 you define a custom package like this, you are really @emph{adding} a
7918 new package definition; the original one remains available.
7920 You can just as well define variants with a different set of
7921 dependencies than the original package. For example, the default
7922 @code{gdb} package depends on @code{guile}, but since that is an
7923 optional dependency, you can define a variant that removes that
7927 (use-modules (gnu packages gdb)) ;for 'gdb'
7929 (define gdb-sans-guile
7932 (inputs (modify-inputs (package-inputs gdb)
7933 (delete "guile")))))
7936 The @code{modify-inputs} form above removes the @code{"guile"} package
7937 from the @code{inputs} field of @code{gdb}. The @code{modify-inputs}
7938 macro is a helper that can prove useful anytime you want to remove, add,
7939 or replace package inputs.
7941 @deffn {Scheme Syntax} modify-inputs @var{inputs} @var{clauses}
7942 Modify the given package inputs, as returned by @code{package-inputs} & co.,
7943 according to the given clauses. Each clause must have one of the
7947 @item (delete @var{name}@dots{})
7948 Delete from the inputs packages with the given @var{name}s (strings).
7950 @item (append @var{package}@dots{})
7951 Add @var{package}s to the end of the input list.
7953 @item (prepend @var{package}@dots{})
7954 Add @var{package}s to the front of the input list.
7957 The example below removes the GMP and ACL inputs of Coreutils and adds
7958 libcap to the back of the input list:
7961 (modify-inputs (package-inputs coreutils)
7962 (delete "gmp" "acl")
7966 The example below replaces the @code{guile} package from the inputs of
7967 @code{guile-redis} with @code{guile-2.2}:
7970 (modify-inputs (package-inputs guile-redis)
7971 (replace "guile" guile-2.2))
7974 The last type of clause is @code{prepend}, to add inputs to the front of
7978 In some cases, you may find it useful to write functions
7979 (``procedures'', in Scheme parlance) that return a package based on some
7980 parameters. For example, consider the @code{luasocket} library for the
7981 Lua programming language. We want to create @code{luasocket} packages
7982 for major versions of Lua. One way to do that is to define a procedure
7983 that takes a Lua package and returns a @code{luasocket} package that
7987 (define (make-lua-socket name lua)
7988 ;; Return a luasocket package built with LUA.
7992 ;; several fields omitted
7994 (synopsis "Socket library for Lua")))
7996 (define-public lua5.1-socket
7997 (make-lua-socket "lua5.1-socket" lua-5.1))
7999 (define-public lua5.2-socket
8000 (make-lua-socket "lua5.2-socket" lua-5.2))
8003 Here we have defined packages @code{lua5.1-socket} and
8004 @code{lua5.2-socket} by calling @code{make-lua-socket} with different
8005 arguments. @xref{Procedures,,, guile, GNU Guile Reference Manual}, for
8006 more info on procedures. Having top-level public definitions for these
8007 two packages means that they can be referred to from the command line
8008 (@pxref{Package Modules}).
8010 @cindex package transformations
8011 These are pretty simple package variants. As a convenience, the
8012 @code{(guix transformations)} module provides a high-level interface
8013 that directly maps to the more sophisticated package transformation
8014 options (@pxref{Package Transformation Options}):
8016 @deffn {Scheme Procedure} options->transformation @var{opts}
8017 Return a procedure that, when passed an object to build (package,
8018 derivation, etc.), applies the transformations specified by @var{opts} and returns
8019 the resulting objects. @var{opts} must be a list of symbol/string pairs such as:
8022 ((with-branch . "guile-gcrypt=master")
8023 (without-tests . "libgcrypt"))
8026 Each symbol names a transformation and the corresponding string is an argument
8027 to that transformation.
8030 For instance, a manifest equivalent to this command:
8034 --with-branch=guile-gcrypt=master \
8035 --with-debug-info=zlib
8039 ... would look like this:
8042 (use-modules (guix transformations))
8045 ;; The package transformation procedure.
8046 (options->transformation
8047 '((with-branch . "guile-gcrypt=master")
8048 (with-debug-info . "zlib"))))
8051 (list (transform (specification->package "guix"))))
8054 @cindex input rewriting
8055 @cindex dependency graph rewriting
8056 The @code{options->transformation} procedure is convenient, but it's
8057 perhaps also not as flexible as you may like. How is it implemented?
8058 The astute reader probably noticed that most package transformation
8059 options go beyond the superficial changes shown in the first examples of
8060 this section: they involve @dfn{input rewriting}, whereby the dependency
8061 graph of a package is rewritten by replacing specific inputs by others.
8063 Dependency graph rewriting, for the purposes of swapping packages in the
8064 graph, is what the @code{package-input-rewriting} procedure in
8065 @code{(guix packages)} implements.
8067 @deffn {Scheme Procedure} package-input-rewriting @var{replacements} @
8068 [@var{rewrite-name}] [#:deep? #t]
8069 Return a procedure that, when passed a package, replaces its direct and
8070 indirect dependencies, including implicit inputs when @var{deep?} is
8071 true, according to @var{replacements}. @var{replacements} is a list of
8072 package pairs; the first element of each pair is the package to replace,
8073 and the second one is the replacement.
8075 Optionally, @var{rewrite-name} is a one-argument procedure that takes
8076 the name of a package and returns its new name after rewrite.
8080 Consider this example:
8083 (define libressl-instead-of-openssl
8084 ;; This is a procedure to replace OPENSSL by LIBRESSL,
8086 (package-input-rewriting `((,openssl . ,libressl))))
8088 (define git-with-libressl
8089 (libressl-instead-of-openssl git))
8093 Here we first define a rewriting procedure that replaces @var{openssl}
8094 with @var{libressl}. Then we use it to define a @dfn{variant} of the
8095 @var{git} package that uses @var{libressl} instead of @var{openssl}.
8096 This is exactly what the @option{--with-input} command-line option does
8097 (@pxref{Package Transformation Options, @option{--with-input}}).
8099 The following variant of @code{package-input-rewriting} can match packages to
8100 be replaced by name rather than by identity.
8102 @deffn {Scheme Procedure} package-input-rewriting/spec @var{replacements} [#:deep? #t]
8103 Return a procedure that, given a package, applies the given
8104 @var{replacements} to all the package graph, including implicit inputs
8105 unless @var{deep?} is false. @var{replacements} is a list of
8106 spec/procedures pair; each spec is a package specification such as
8107 @code{"gcc"} or @code{"guile@@2"}, and each procedure takes a matching
8108 package and returns a replacement for that package.
8111 The example above could be rewritten this way:
8114 (define libressl-instead-of-openssl
8115 ;; Replace all the packages called "openssl" with LibreSSL.
8116 (package-input-rewriting/spec `(("openssl" . ,(const libressl)))))
8119 The key difference here is that, this time, packages are matched by spec and
8120 not by identity. In other words, any package in the graph that is called
8121 @code{openssl} will be replaced.
8123 A more generic procedure to rewrite a package dependency graph is
8124 @code{package-mapping}: it supports arbitrary changes to nodes in the
8127 @deffn {Scheme Procedure} package-mapping @var{proc} [@var{cut?}] [#:deep? #f]
8128 Return a procedure that, given a package, applies @var{proc} to all the packages
8129 depended on and returns the resulting package. The procedure stops recursion
8130 when @var{cut?} returns true for a given package. When @var{deep?} is true, @var{proc} is
8131 applied to implicit inputs as well.
8134 @node Writing Manifests
8135 @section Writing Manifests
8138 @cindex bill of materials (manifests)
8139 @command{guix} commands let you specify package lists on the command
8140 line. This is convenient, but as the command line becomes longer and
8141 less trivial, it quickly becomes more convenient to have that package
8142 list in what we call a @dfn{manifest}. A manifest is some sort of a
8143 ``bill of materials'' that defines a package set. You would typically
8144 come up with a code snippet that builds the manifest, store it in a
8145 file, say @file{manifest.scm}, and then pass that file to the
8146 @option{-m} (or @option{--manifest}) option that many @command{guix}
8147 commands support. For example, here's what a manifest for a simple
8148 package set might look like:
8151 ;; Manifest for three packages.
8152 (specifications->manifest '("gcc-toolchain" "make" "git"))
8155 Once you have that manifest, you can pass it, for example, to
8156 @command{guix package} to install just those three packages to your
8157 profile (@pxref{profile-manifest, @option{-m} option of @command{guix
8161 guix package -m manifest.scm
8165 ... or you can pass it to @command{guix shell} (@pxref{shell-manifest,
8166 @command{-m} option of @command{guix shell}}) to spawn an ephemeral
8170 guix shell -m manifest.scm
8174 ... or you can pass it to @command{guix pack} in pretty much the same
8175 way (@pxref{pack-manifest, @option{-m} option of @command{guix pack}}).
8176 You can store the manifest under version control, share it with others
8177 so they can easily get set up, etc.
8179 But how do you write your first manifest? To get started, maybe you'll
8180 want to write a manifest that mirrors what you already have in a
8181 profile. Rather than start from a blank page, @command{guix package}
8182 can generate a manifest for you (@pxref{export-manifest, @command{guix
8183 package --export-manifest}}):
8186 # Write to 'manifest.scm' a manifest corresponding to the
8187 # default profile, ~/.guix-profile.
8188 guix package --export-manifest > manifest.scm
8191 Or maybe you'll want to ``translate'' command-line arguments into a
8192 manifest. In that case, @command{guix shell} can help
8193 (@pxref{shell-export-manifest, @command{guix shell --export-manifest}}):
8196 # Write a manifest for the packages specified on the command line.
8197 guix shell --export-manifest gcc-toolchain make git > manifest.scm
8200 In both cases, the @option{--export-manifest} option tries hard to
8201 generate a faithful manifest; in particular, it takes package
8202 transformation options into account (@pxref{Package Transformation
8206 Manifests are @emph{symbolic}: they refer to packages of the channels
8207 @emph{currently in use} (@pxref{Channels}). In the example above,
8208 @code{gcc-toolchain} might refer to version 11 today, but it might refer
8209 to version 13 two years from now.
8211 If you want to ``pin'' your software environment to specific package
8212 versions and variants, you need an additional piece of information: the
8213 list of channel revisions in use, as returned by @command{guix
8214 describe}. @xref{Replicating Guix}, for more information.
8217 Once you've obtained your first manifest, perhaps you'll want to
8218 customize it. Since your manifest is code, you now have access to all
8219 the Guix programming interfaces!
8221 Let's assume you want a manifest to deploy a custom variant of GDB, the
8222 GNU Debugger, that does not depend on Guile, together with another
8223 package. Building on the example seen in the previous section
8224 (@pxref{Defining Package Variants}), you can write a manifest along
8228 (use-modules (guix packages)
8229 (gnu packages gdb) ;for 'gdb'
8230 (gnu packages version-control)) ;for 'git'
8232 ;; Define a variant of GDB without a dependency on Guile.
8233 (define gdb-sans-guile
8236 (inputs (modify-inputs (package-inputs gdb)
8237 (delete "guile")))))
8239 ;; Return a manifest containing that one package plus Git.
8240 (packages->manifest (list gdb-sans-guile git))
8243 Note that in this example, the manifest directly refers to the
8244 @code{gdb} and @code{git} variables, which are bound to a @code{package}
8245 object (@pxref{package Reference}), instead of calling
8246 @code{specifications->manifest} to look up packages by name as we did
8247 before. The @code{use-modules} form at the top lets us access the core
8248 package interface (@pxref{Defining Packages}) and the modules that
8249 define @code{gdb} and @code{git} (@pxref{Package Modules}). Seamlessly,
8250 we're weaving all this together---the possibilities are endless, unleash
8253 The data type for manifests as well as supporting procedures are defined
8254 in the @code{(guix profiles)} module, which is automatically available
8255 to code passed to @option{-m}. The reference follows.
8257 @deftp {Data Type} manifest
8258 Data type representing a manifest.
8260 It currently has one field:
8264 This must be a list of @code{manifest-entry} records---see below.
8268 @deftp {Data Type} manifest-entry
8269 Data type representing a manifest entry. A manifest entry contains
8270 essential metadata: a name and version string, the object (usually a
8271 package) for that entry, the desired output (@pxref{Packages with
8272 Multiple Outputs}), and a number of optional pieces of information
8275 Most of the time, you won't build a manifest entry directly; instead,
8276 you will pass a package to @code{package->manifest-entry}, described
8277 below. In some unusual cases though, you might want to create manifest
8278 entries for things that are @emph{not} packages, as in this example:
8281 ;; Manually build a single manifest entry for a non-package object.
8282 (let ((hello (program-file "hello" #~(display "Hi!"))))
8287 (computed-file "hello-directory"
8288 #~(let ((bin (string-append #$output "/bin")))
8289 (mkdir #$output) (mkdir bin)
8291 (string-append bin "/hello")))))))
8294 The available fields are the following:
8298 @itemx @code{version}
8299 Name and version string for this entry.
8302 A package or other file-like object (@pxref{G-Expressions, file-like
8305 @item @code{output} (default: @code{"out"})
8306 Output of @code{item} to use, in case @code{item} has multiple outputs
8307 (@pxref{Packages with Multiple Outputs}).
8309 @item @code{dependencies} (default: @code{'()})
8310 List of manifest entries this entry depends on. When building a
8311 profile, dependencies are added to the profile.
8313 Typically, the propagated inputs of a package (@pxref{package Reference,
8314 @code{propagated-inputs}}) end up having a corresponding manifest entry
8315 in among the dependencies of the package's own manifest entry.
8317 @item @code{search-paths} (default: @code{'()})
8318 The list of search path specifications honored by this entry
8319 (@pxref{Search Paths}).
8321 @item @code{properties} (default: @code{'()})
8322 List of symbol/value pairs. When building a profile, those properties
8325 This can be used to piggyback additional metadata---e.g., the
8326 transformations applied to a package (@pxref{Package Transformation
8329 @item @code{parent} (default: @code{(delay #f)})
8330 A promise pointing to the ``parent'' manifest entry.
8332 This is used as a hint to provide context when reporting an error
8333 related to a manifest entry coming from a @code{dependencies} field.
8337 @deffn {Scheme Procedure} concatenate-manifests @var{lst}
8338 Concatenate the manifests listed in @var{lst} and return the resulting
8342 @c TODO: <manifest-pattern>, manifest-lookup, manifest-remove, etc.
8344 @deffn {Scheme Procedure} package->manifest-entry @var{package} @
8345 [@var{output}] [#:properties]
8346 Return a manifest entry for the @var{output} of package @var{package},
8347 where @var{output} defaults to @code{"out"}, and with the given
8348 @var{properties}. By default @var{properties} is the empty list or, if
8349 one or more package transformations were applied to @var{package}, it is
8350 an association list representing those transformations, suitable as an
8351 argument to @code{options->transformation} (@pxref{Defining Package
8352 Variants, @code{options->transformation}}).
8354 The code snippet below builds a manifest with an entry for the default
8355 output and the @code{send-email} output of the @code{git} package:
8358 (use-modules (gnu packages version-control))
8360 (manifest (list (package->manifest-entry git)
8361 (package->manifest-entry git "send-email")))
8365 @deffn {Scheme Procedure} packages->manifest @var{packages}
8366 Return a list of manifest entries, one for each item listed in
8367 @var{packages}. Elements of @var{packages} can be either package
8368 objects or package/string tuples denoting a specific output of a
8371 Using this procedure, the manifest above may be rewritten more
8375 (use-modules (gnu packages version-control))
8377 (packages->manifest (list git `(,git "send-email")))
8381 @anchor{package-development-manifest}
8382 @deffn {Scheme Procedure} package->development-manifest @var{package} @
8383 [@var{system}] [#:target]
8384 Return a manifest for the @dfn{development inputs} of @var{package} for
8385 @var{system}, optionally when cross-compiling to @var{target}.
8386 Development inputs include both explicit and implicit inputs of
8389 Like the @option{-D} option of @command{guix shell}
8390 (@pxref{shell-development-option, @command{guix shell -D}}), the
8391 resulting manifest describes the environment in which one can develop
8392 @var{package}. For example, suppose you're willing to set up a
8393 development environment for Inkscape, with the addition of Git for
8394 version control; you can describe that ``bill of materials'' with the
8398 (use-modules (gnu packages inkscape) ;for 'inkscape'
8399 (gnu packages version-control)) ;for 'git'
8401 (concatenate-manifests
8402 (list (package->development-manifest inkscape)
8403 (packages->manifest (list git))))
8406 In this example, the development manifest that
8407 @code{package->development-manifest} returns includes the compiler
8408 (GCC), the many supporting libraries (Boost, GLib, GTK, etc.), and a
8409 couple of additional development tools---these are the dependencies
8410 @command{guix show inkscape} lists.
8413 @c TODO: Move (gnu packages) interface to a section of its own.
8415 Last, the @code{(gnu packages)} module provides higher-level facilities
8416 to build manifests. In particular, it lets you look up packages by
8419 @deffn {Scheme Procedure} specifications->manifest @var{specs}
8420 Given @var{specs}, a list of specifications such as @code{"emacs@@25.2"}
8421 or @code{"guile:debug"}, return a manifest. Specs have the format that
8422 command-line tools such as @command{guix install} and @command{guix
8423 package} understand (@pxref{Invoking guix package}).
8425 As an example, it lets you rewrite the Git manifest that we saw earlier
8429 (specifications->manifest '("git" "git:send-email"))
8432 Notice that we do not need to worry about @code{use-modules}, importing
8433 the right set of modules, and referring to the right variables.
8434 Instead, we directly refer to packages in the same way as on the command
8435 line, which can often be more convenient.
8438 @c TODO: specifications->package, etc.
8442 @section Build Systems
8444 @cindex build system
8445 Each package definition specifies a @dfn{build system} and arguments for
8446 that build system (@pxref{Defining Packages}). This @code{build-system}
8447 field represents the build procedure of the package, as well as implicit
8448 dependencies of that build procedure.
8450 Build systems are @code{<build-system>} objects. The interface to
8451 create and manipulate them is provided by the @code{(guix build-system)}
8452 module, and actual build systems are exported by specific modules.
8454 @cindex bag (low-level package representation)
8455 Under the hood, build systems first compile package objects to
8456 @dfn{bags}. A @dfn{bag} is like a package, but with less
8457 ornamentation---in other words, a bag is a lower-level representation of
8458 a package, which includes all the inputs of that package, including some
8459 that were implicitly added by the build system. This intermediate
8460 representation is then compiled to a derivation (@pxref{Derivations}).
8461 The @code{package-with-c-toolchain} is an example of a way to change the
8462 implicit inputs that a package's build system pulls in (@pxref{package
8463 Reference, @code{package-with-c-toolchain}}).
8465 Build systems accept an optional list of @dfn{arguments}. In package
8466 definitions, these are passed @i{via} the @code{arguments} field
8467 (@pxref{Defining Packages}). They are typically keyword arguments
8468 (@pxref{Optional Arguments, keyword arguments in Guile,, guile, GNU
8469 Guile Reference Manual}). The value of these arguments is usually
8470 evaluated in the @dfn{build stratum}---i.e., by a Guile process launched
8471 by the daemon (@pxref{Derivations}).
8473 The main build system is @code{gnu-build-system}, which implements the
8474 standard build procedure for GNU and many other packages. It
8475 is provided by the @code{(guix build-system gnu)} module.
8477 @defvr {Scheme Variable} gnu-build-system
8478 @code{gnu-build-system} represents the GNU Build System, and variants
8479 thereof (@pxref{Configuration, configuration and makefile conventions,,
8480 standards, GNU Coding Standards}).
8482 @cindex build phases
8483 In a nutshell, packages using it are configured, built, and installed with
8484 the usual @code{./configure && make && make check && make install}
8485 command sequence. In practice, a few additional steps are often needed.
8486 All these steps are split up in separate @dfn{phases}.
8487 @xref{Build Phases}, for more info on build phases and ways to customize
8490 In addition, this build system ensures that the ``standard'' environment
8491 for GNU packages is available. This includes tools such as GCC, libc,
8492 Coreutils, Bash, Make, Diffutils, grep, and sed (see the @code{(guix
8493 build-system gnu)} module for a complete list). We call these the
8494 @dfn{implicit inputs} of a package, because package definitions do not
8495 have to mention them.
8497 This build system supports a number of keyword arguments, which can be
8498 passed @i{via} the @code{arguments} field of a package. Here are some
8499 of the main parameters:
8503 This argument specifies build-side code that evaluates to an alist of
8504 build phases. @xref{Build Phases}, for more information.
8506 @item #:configure-flags
8507 This is a list of flags (strings) passed to the @command{configure}
8508 script. @xref{Defining Packages}, for an example.
8511 This list of strings contains flags passed as arguments to
8512 @command{make} invocations in the @code{build}, @code{check}, and
8513 @code{install} phases.
8515 @item #:out-of-source?
8516 This Boolean, @code{#f} by default, indicates whether to run builds in a
8517 build directory separate from the source tree.
8519 When it is true, the @code{configure} phase creates a separate build
8520 directory, changes to that directory, and runs the @code{configure}
8521 script from there. This is useful for packages that require it, such as
8525 This Boolean, @code{#t} by default, indicates whether the @code{check}
8526 phase should run the package's test suite.
8529 This string, @code{"check"} by default, gives the name of the makefile
8530 target used by the @code{check} phase.
8532 @item #:parallel-build?
8533 @itemx #:parallel-tests?
8534 These Boolean values specify whether to build, respectively run the test
8535 suite, in parallel, with the @code{-j} flag of @command{make}. When
8536 they are true, @code{make} is passed @code{-j@var{n}}, where @var{n} is
8537 the number specified as the @option{--cores} option of
8538 @command{guix-daemon} or that of the @command{guix} client command
8539 (@pxref{Common Build Options, @option{--cores}}).
8541 @cindex RUNPATH, validation
8542 @item #:validate-runpath?
8543 This Boolean, @code{#t} by default, determines whether to ``validate''
8544 the @code{RUNPATH} of ELF binaries (@code{.so} shared libraries as well
8545 as executables) previously installed by the @code{install} phase.
8546 @xref{phase-validate-runpath, the @code{validate-runpath} phase}, for
8549 @item #:substitutable?
8550 This Boolean, @code{#t} by default, tells whether the package outputs
8551 should be substitutable---i.e., whether users should be able to obtain
8552 substitutes for them instead of building locally (@pxref{Substitutes}).
8554 @item #:allowed-references
8555 @itemx #:disallowed-references
8556 When true, these arguments must be a list of dependencies that must not
8557 appear among the references of the build results. If, upon build
8558 completion, some of these references are retained, the build process
8561 This is useful to ensure that a package does not erroneously keep a
8562 reference to some of it build-time inputs, in cases where doing so
8563 would, for example, unnecessarily increase its size (@pxref{Invoking
8567 Most other build systems support these keyword arguments.
8570 Other @code{<build-system>} objects are defined to support other
8571 conventions and tools used by free software packages. They inherit most
8572 of @code{gnu-build-system}, and differ mainly in the set of inputs
8573 implicitly added to the build process, and in the list of phases
8574 executed. Some of these build systems are listed below.
8576 @defvr {Scheme Variable} ant-build-system
8577 This variable is exported by @code{(guix build-system ant)}. It
8578 implements the build procedure for Java packages that can be built with
8579 @url{https://ant.apache.org/, Ant build tool}.
8581 It adds both @code{ant} and the @dfn{Java Development Kit} (JDK) as
8582 provided by the @code{icedtea} package to the set of inputs. Different
8583 packages can be specified with the @code{#:ant} and @code{#:jdk}
8584 parameters, respectively.
8586 When the original package does not provide a suitable Ant build file,
8587 the parameter @code{#:jar-name} can be used to generate a minimal Ant
8588 build file @file{build.xml} with tasks to build the specified jar
8589 archive. In this case the parameter @code{#:source-dir} can be used to
8590 specify the source sub-directory, defaulting to ``src''.
8592 The @code{#:main-class} parameter can be used with the minimal ant
8593 buildfile to specify the main class of the resulting jar. This makes the
8594 jar file executable. The @code{#:test-include} parameter can be used to
8595 specify the list of junit tests to run. It defaults to
8596 @code{(list "**/*Test.java")}. The @code{#:test-exclude} can be used to
8597 disable some tests. It defaults to @code{(list "**/Abstract*.java")},
8598 because abstract classes cannot be run as tests.
8600 The parameter @code{#:build-target} can be used to specify the Ant task
8601 that should be run during the @code{build} phase. By default the
8602 ``jar'' task will be run.
8606 @defvr {Scheme Variable} android-ndk-build-system
8607 @cindex Android distribution
8608 @cindex Android NDK build system
8609 This variable is exported by @code{(guix build-system android-ndk)}. It
8610 implements a build procedure for Android NDK (native development kit)
8611 packages using a Guix-specific build process.
8613 The build system assumes that packages install their public interface
8614 (header) files to the subdirectory @file{include} of the @code{out} output and
8615 their libraries to the subdirectory @file{lib} the @code{out} output.
8617 It's also assumed that the union of all the dependencies of a package
8618 has no conflicting files.
8620 For the time being, cross-compilation is not supported - so right now
8621 the libraries and header files are assumed to be host tools.
8625 @defvr {Scheme Variable} asdf-build-system/source
8626 @defvrx {Scheme Variable} asdf-build-system/sbcl
8627 @defvrx {Scheme Variable} asdf-build-system/ecl
8629 These variables, exported by @code{(guix build-system asdf)}, implement
8630 build procedures for Common Lisp packages using
8631 @url{https://common-lisp.net/project/asdf/, ``ASDF''}. ASDF is a system
8632 definition facility for Common Lisp programs and libraries.
8634 The @code{asdf-build-system/source} system installs the packages in
8635 source form, and can be loaded using any common lisp implementation, via
8636 ASDF@. The others, such as @code{asdf-build-system/sbcl}, install binary
8637 systems in the format which a particular implementation understands.
8638 These build systems can also be used to produce executable programs, or
8639 lisp images which contain a set of packages pre-loaded.
8641 The build system uses naming conventions. For binary packages, the
8642 package name should be prefixed with the lisp implementation, such as
8643 @code{sbcl-} for @code{asdf-build-system/sbcl}.
8645 Additionally, the corresponding source package should be labeled using
8646 the same convention as python packages (see @ref{Python Modules}), using
8647 the @code{cl-} prefix.
8649 In order to create executable programs and images, the build-side
8650 procedures @code{build-program} and @code{build-image} can be used.
8651 They should be called in a build phase after the
8652 @code{create-asdf-configuration} phase, so that the system which was
8653 just built can be used within the resulting image. @code{build-program}
8654 requires a list of Common Lisp expressions to be passed as the
8655 @code{#:entry-program} argument.
8657 By default, all the @file{.asd} files present in the sources are read to
8658 find system definitions. The @code{#:asd-files} parameter can be used
8659 to specify the list of @file{.asd} files to read. Furthermore, if the
8660 package defines a system for its tests in a separate file, it will be
8661 loaded before the tests are run if it is specified by the
8662 @code{#:test-asd-file} parameter. If it is not set, the files
8663 @code{<system>-tests.asd}, @code{<system>-test.asd}, @code{tests.asd},
8664 and @code{test.asd} will be tried if they exist.
8666 If for some reason the package must be named in a different way than the
8667 naming conventions suggest, or if several systems must be compiled, the
8668 @code{#:asd-systems} parameter can be used to specify the list of system
8673 @defvr {Scheme Variable} cargo-build-system
8674 @cindex Rust programming language
8675 @cindex Cargo (Rust build system)
8676 This variable is exported by @code{(guix build-system cargo)}. It
8677 supports builds of packages using Cargo, the build tool of the
8678 @uref{https://www.rust-lang.org, Rust programming language}.
8680 It adds @code{rustc} and @code{cargo} to the set of inputs.
8681 A different Rust package can be specified with the @code{#:rust} parameter.
8683 Regular cargo dependencies should be added to the package definition similarly
8684 to other packages; those needed only at build time to native-inputs, others to
8685 inputs. If you need to add source-only crates then you should add them to via
8686 the @code{#:cargo-inputs} parameter as a list of name and spec pairs, where the
8687 spec can be a package or a source definition. Note that the spec must
8688 evaluate to a path to a gzipped tarball which includes a @code{Cargo.toml}
8689 file at its root, or it will be ignored. Similarly, cargo dev-dependencies
8690 should be added to the package definition via the
8691 @code{#:cargo-development-inputs} parameter.
8693 In its @code{configure} phase, this build system will make any source inputs
8694 specified in the @code{#:cargo-inputs} and @code{#:cargo-development-inputs}
8695 parameters available to cargo. It will also remove an included
8696 @code{Cargo.lock} file to be recreated by @code{cargo} during the
8697 @code{build} phase. The @code{package} phase will run @code{cargo package}
8698 to create a source crate for future use. The @code{install} phase installs
8699 the binaries defined by the crate. Unless @code{install-source? #f} is
8700 defined it will also install a source crate repository of itself and unpacked
8701 sources, to ease in future hacking on rust packages.
8704 @defvr {Scheme Variable} chicken-build-system
8705 This variable is exported by @code{(guix build-system chicken)}. It
8706 builds @uref{https://call-cc.org/, CHICKEN Scheme} modules, also called
8707 ``eggs'' or ``extensions''. CHICKEN generates C source code, which then
8708 gets compiled by a C compiler, in this case GCC.
8710 This build system adds @code{chicken} to the package inputs, as well as
8711 the packages of @code{gnu-build-system}.
8713 The build system can't (yet) deduce the egg's name automatically, so just like
8714 with @code{go-build-system} and its @code{#:import-path}, you should define
8715 @code{#:egg-name} in the package's @code{arguments} field.
8717 For example, if you are packaging the @code{srfi-1} egg:
8720 (arguments '(#:egg-name "srfi-1"))
8723 Egg dependencies must be defined in @code{propagated-inputs}, not @code{inputs}
8724 because CHICKEN doesn't embed absolute references in compiled eggs.
8725 Test dependencies should go to @code{native-inputs}, as usual.
8728 @defvr {Scheme Variable} copy-build-system
8729 This variable is exported by @code{(guix build-system copy)}. It
8730 supports builds of simple packages that don't require much compiling,
8731 mostly just moving files around.
8733 It adds much of the @code{gnu-build-system} packages to the set of
8734 inputs. Because of this, the @code{copy-build-system} does not require
8735 all the boilerplate code often needed for the
8736 @code{trivial-build-system}.
8738 To further simplify the file installation process, an
8739 @code{#:install-plan} argument is exposed to let the packager specify
8740 which files go where. The install plan is a list of @code{(@var{source}
8741 @var{target} [@var{filters}])}. @var{filters} are optional.
8744 @item When @var{source} matches a file or directory without trailing slash, install it to @var{target}.
8746 @item If @var{target} has a trailing slash, install @var{source} basename beneath @var{target}.
8747 @item Otherwise install @var{source} as @var{target}.
8750 @item When @var{source} is a directory with a trailing slash, or when @var{filters} are used,
8751 the trailing slash of @var{target} is implied with the same meaning
8754 @item Without @var{filters}, install the full @var{source} @emph{content} to @var{target}.
8755 @item With @var{filters} among @code{#:include}, @code{#:include-regexp}, @code{#:exclude},
8756 @code{#:exclude-regexp}, only select files are installed depending on
8757 the filters. Each filters is specified by a list of strings.
8759 @item With @code{#:include}, install all the files which the path suffix matches
8760 at least one of the elements in the given list.
8761 @item With @code{#:include-regexp}, install all the files which the
8762 subpaths match at least one of the regular expressions in the given
8764 @item The @code{#:exclude} and @code{#:exclude-regexp} filters
8765 are the complement of their inclusion counterpart. Without @code{#:include} flags,
8766 install all files but those matching the exclusion filters.
8767 If both inclusions and exclusions are specified, the exclusions are done
8768 on top of the inclusions.
8771 In all cases, the paths relative to @var{source} are preserved within
8778 @item @code{("foo/bar" "share/my-app/")}: Install @file{bar} to @file{share/my-app/bar}.
8779 @item @code{("foo/bar" "share/my-app/baz")}: Install @file{bar} to @file{share/my-app/baz}.
8780 @item @code{("foo/" "share/my-app")}: Install the content of @file{foo} inside @file{share/my-app},
8781 e.g., install @file{foo/sub/file} to @file{share/my-app/sub/file}.
8782 @item @code{("foo/" "share/my-app" #:include ("sub/file"))}: Install only @file{foo/sub/file} to
8783 @file{share/my-app/sub/file}.
8784 @item @code{("foo/sub" "share/my-app" #:include ("file"))}: Install @file{foo/sub/file} to
8785 @file{share/my-app/file}.
8790 @cindex Clojure (programming language)
8791 @cindex simple Clojure build system
8792 @defvr {Scheme Variable} clojure-build-system
8793 This variable is exported by @code{(guix build-system clojure)}. It implements
8794 a simple build procedure for @uref{https://clojure.org/, Clojure} packages
8795 using plain old @code{compile} in Clojure. Cross-compilation is not supported
8798 It adds @code{clojure}, @code{icedtea} and @code{zip} to the set of inputs.
8799 Different packages can be specified with the @code{#:clojure}, @code{#:jdk} and
8800 @code{#:zip} parameters, respectively.
8802 A list of source directories, test directories and jar names can be specified
8803 with the @code{#:source-dirs}, @code{#:test-dirs} and @code{#:jar-names}
8804 parameters, respectively. Compile directory and main class can be specified
8805 with the @code{#:compile-dir} and @code{#:main-class} parameters, respectively.
8806 Other parameters are documented below.
8808 This build system is an extension of @code{ant-build-system}, but with the
8809 following phases changed:
8814 This phase calls @code{compile} in Clojure to compile source files and runs
8815 @command{jar} to create jars from both source files and compiled files
8816 according to the include list and exclude list specified in
8817 @code{#:aot-include} and @code{#:aot-exclude}, respectively. The exclude list
8818 has priority over the include list. These lists consist of symbols
8819 representing Clojure libraries or the special keyword @code{#:all} representing
8820 all Clojure libraries found under the source directories. The parameter
8821 @code{#:omit-source?} decides if source should be included into the jars.
8824 This phase runs tests according to the include list and exclude list specified
8825 in @code{#:test-include} and @code{#:test-exclude}, respectively. Their
8826 meanings are analogous to that of @code{#:aot-include} and
8827 @code{#:aot-exclude}, except that the special keyword @code{#:all} now
8828 stands for all Clojure libraries found under the test directories. The
8829 parameter @code{#:tests?} decides if tests should be run.
8832 This phase installs all jars built previously.
8835 Apart from the above, this build system also contains an additional phase:
8840 This phase installs all top-level files with base name matching
8841 @code{%doc-regex}. A different regex can be specified with the
8842 @code{#:doc-regex} parameter. All files (recursively) inside the documentation
8843 directories specified in @code{#:doc-dirs} are installed as well.
8847 @defvr {Scheme Variable} cmake-build-system
8848 This variable is exported by @code{(guix build-system cmake)}. It
8849 implements the build procedure for packages using the
8850 @url{https://www.cmake.org, CMake build tool}.
8852 It automatically adds the @code{cmake} package to the set of inputs.
8853 Which package is used can be specified with the @code{#:cmake}
8856 The @code{#:configure-flags} parameter is taken as a list of flags
8857 passed to the @command{cmake} command. The @code{#:build-type}
8858 parameter specifies in abstract terms the flags passed to the compiler;
8859 it defaults to @code{"RelWithDebInfo"} (short for ``release mode with
8860 debugging information''), which roughly means that code is compiled with
8861 @code{-O2 -g}, as is the case for Autoconf-based packages by default.
8864 @defvr {Scheme Variable} dune-build-system
8865 This variable is exported by @code{(guix build-system dune)}. It
8866 supports builds of packages using @uref{https://dune.build/, Dune}, a build
8867 tool for the OCaml programming language. It is implemented as an extension
8868 of the @code{ocaml-build-system} which is described below. As such, the
8869 @code{#:ocaml} and @code{#:findlib} parameters can be passed to this build
8872 It automatically adds the @code{dune} package to the set of inputs.
8873 Which package is used can be specified with the @code{#:dune}
8876 There is no @code{configure} phase because dune packages typically don't
8877 need to be configured. The @code{#:build-flags} parameter is taken as a
8878 list of flags passed to the @code{dune} command during the build.
8880 The @code{#:jbuild?} parameter can be passed to use the @code{jbuild}
8881 command instead of the more recent @code{dune} command while building
8882 a package. Its default value is @code{#f}.
8884 The @code{#:package} parameter can be passed to specify a package name, which
8885 is useful when a package contains multiple packages and you want to build
8886 only one of them. This is equivalent to passing the @code{-p} argument to
8891 @defvr {Scheme variable} elm-build-system
8892 This variable is exported by @code{(guix build-system elm)}. It implements a
8893 build procedure for @url{https://elm-lang.org, Elm} packages similar to
8896 The build system adds an Elm compiler package to the set of inputs. The
8897 default compiler package (currently @code{elm-sans-reactor}) can be overridden
8898 using the @code{#:elm} argument. Additionally, Elm packages needed by the
8899 build system itself are added as implicit inputs if they are not already
8900 present: to suppress this behavior, use the
8901 @code{#:implicit-elm-package-inputs?} argument, which is primarily useful for
8904 The @code{"dependencies"} and @code{"test-dependencies"} in an Elm package's
8905 @file{elm.json} file correspond to @code{propagated-inputs} and @code{inputs},
8908 Elm requires a particular structure for package names: @pxref{Elm Packages}
8909 for more details, including utilities provided by @code{(guix build-system
8912 There are currently a few noteworthy limitations to @code{elm-build-system}:
8916 The build system is focused on @dfn{packages} in the Elm sense of the word:
8917 Elm @dfn{projects} which declare @code{@{ "type": "package" @}} in their
8918 @file{elm.json} files. Using @code{elm-build-system} to build Elm
8919 @dfn{applications} (which declare @code{@{ "type": "application" @}}) is
8920 possible, but requires ad-hoc modifications to the build phases. For
8921 examples, see the definitions of the @code{elm-todomvc} example application and
8922 the @code{elm} package itself (because the front-end for the
8923 @samp{elm reactor} command is an Elm application).
8926 Elm supports multiple versions of a package coexisting simultaneously under
8927 @env{ELM_HOME}, but this does not yet work well with @code{elm-build-system}.
8928 This limitation primarily affects Elm applications, because they specify
8929 exact versions for their dependencies, whereas Elm packages specify supported
8930 version ranges. As a workaround, the example applications mentioned above use
8931 the @code{patch-application-dependencies} procedure provided by
8932 @code{(guix build elm-build-system)} to rewrite their @file{elm.json} files to
8933 refer to the package versions actually present in the build environment.
8934 Alternatively, Guix package transformations (@pxref{Defining Package
8935 Variants}) could be used to rewrite an application's entire dependency graph.
8938 We are not yet able to run tests for Elm projects because neither
8939 @url{https://github.com/mpizenberg/elm-test-rs, @command{elm-test-rs}} nor the
8940 Node.js-based @url{https://github.com/rtfeldman/node-test-runner,
8941 @command{elm-test}} runner has been packaged for Guix yet.
8945 @defvr {Scheme Variable} go-build-system
8946 This variable is exported by @code{(guix build-system go)}. It
8947 implements a build procedure for Go packages using the standard
8948 @url{https://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies,
8949 Go build mechanisms}.
8951 The user is expected to provide a value for the key @code{#:import-path}
8952 and, in some cases, @code{#:unpack-path}. The
8953 @url{https://golang.org/doc/code.html#ImportPaths, import path}
8954 corresponds to the file system path expected by the package's build
8955 scripts and any referring packages, and provides a unique way to
8956 refer to a Go package. It is typically based on a combination of the
8957 package source code's remote URI and file system hierarchy structure. In
8958 some cases, you will need to unpack the package's source code to a
8959 different directory structure than the one indicated by the import path,
8960 and @code{#:unpack-path} should be used in such cases.
8962 Packages that provide Go libraries should install their source code into
8963 the built output. The key @code{#:install-source?}, which defaults to
8964 @code{#t}, controls whether or not the source code is installed. It can
8965 be set to @code{#f} for packages that only provide executable files.
8967 Packages can be cross-built, and if a specific architecture or operating
8968 system is desired then the keywords @code{#:goarch} and @code{#:goos}
8969 can be used to force the package to be built for that architecture and
8970 operating system. The combinations known to Go can be found
8971 @url{"https://golang.org/doc/install/source#environment", in their
8975 @defvr {Scheme Variable} glib-or-gtk-build-system
8976 This variable is exported by @code{(guix build-system glib-or-gtk)}. It
8977 is intended for use with packages making use of GLib or GTK+.
8979 This build system adds the following two phases to the ones defined by
8980 @code{gnu-build-system}:
8983 @item glib-or-gtk-wrap
8984 The phase @code{glib-or-gtk-wrap} ensures that programs in
8985 @file{bin/} are able to find GLib ``schemas'' and
8986 @uref{https://developer.gnome.org/gtk3/stable/gtk-running.html, GTK+
8987 modules}. This is achieved by wrapping the programs in launch scripts
8988 that appropriately set the @env{XDG_DATA_DIRS} and @env{GTK_PATH}
8989 environment variables.
8991 It is possible to exclude specific package outputs from that wrapping
8992 process by listing their names in the
8993 @code{#:glib-or-gtk-wrap-excluded-outputs} parameter. This is useful
8994 when an output is known not to contain any GLib or GTK+ binaries, and
8995 where wrapping would gratuitously add a dependency of that output on
8998 @item glib-or-gtk-compile-schemas
8999 The phase @code{glib-or-gtk-compile-schemas} makes sure that all
9000 @uref{https://developer.gnome.org/gio/stable/glib-compile-schemas.html,
9001 GSettings schemas} of GLib are compiled. Compilation is performed by the
9002 @command{glib-compile-schemas} program. It is provided by the package
9003 @code{glib:bin} which is automatically imported by the build system.
9004 The @code{glib} package providing @command{glib-compile-schemas} can be
9005 specified with the @code{#:glib} parameter.
9008 Both phases are executed after the @code{install} phase.
9011 @defvr {Scheme Variable} guile-build-system
9012 This build system is for Guile packages that consist exclusively of Scheme
9013 code and that are so lean that they don't even have a makefile, let alone a
9014 @file{configure} script. It compiles Scheme code using @command{guild
9015 compile} (@pxref{Compilation,,, guile, GNU Guile Reference Manual}) and
9016 installs the @file{.scm} and @file{.go} files in the right place. It also
9017 installs documentation.
9019 This build system supports cross-compilation by using the
9020 @option{--target} option of @samp{guild compile}.
9022 Packages built with @code{guile-build-system} must provide a Guile package in
9023 their @code{native-inputs} field.
9026 @defvr {Scheme Variable} julia-build-system
9027 This variable is exported by @code{(guix build-system julia)}. It
9028 implements the build procedure used by @uref{https://julialang.org/,
9029 julia} packages, which essentially is similar to running @samp{julia -e
9030 'using Pkg; Pkg.add(package)'} in an environment where
9031 @env{JULIA_LOAD_PATH} contains the paths to all Julia package inputs.
9032 Tests are run by calling @code{/test/runtests.jl}.
9034 The Julia package name and uuid is read from the file
9035 @file{Project.toml}. These values can be overridden by passing the
9036 argument @code{#:julia-package-name} (which must be correctly
9037 capitalized) or @code{#:julia-package-uuid}.
9039 Julia packages usually manage their binary dependencies via
9040 @code{JLLWrappers.jl}, a Julia package that creates a module (named
9041 after the wrapped library followed by @code{_jll.jl}.
9043 To add the binary path @code{_jll.jl} packages, you need to patch the
9044 files under @file{src/wrappers/}, replacing the call to the macro
9045 @code{JLLWrappers.@@generate_wrapper_header}, adding as a second
9046 argument containing the store path the binary.
9048 As an example, in the MbedTLS Julia package, we add a build phase
9049 (@pxref{Build Phases}) to insert the absolute file name of the wrapped
9053 (add-after 'unpack 'override-binary-path
9054 (lambda* (#:key inputs #:allow-other-keys)
9055 (for-each (lambda (wrapper)
9056 (substitute* wrapper
9057 (("generate_wrapper_header.*")
9059 "generate_wrapper_header(\"MbedTLS\", \""
9060 (assoc-ref inputs "mbedtls-apache") "\")\n"))))
9061 ;; There's a Julia file for each platform, override them all.
9062 (find-files "src/wrappers/" "\\.jl$"))))
9065 Some older packages that aren't using @file{Project.toml} yet, will
9066 require this file to be created, too. It is internally done if the
9067 arguments @code{#:julia-package-name} and @code{#:julia-package-uuid}
9071 @defvr {Scheme Variable} maven-build-system
9072 This variable is exported by @code{(guix build-system maven)}. It implements
9073 a build procedure for @uref{https://maven.apache.org, Maven} packages. Maven
9074 is a dependency and lifecycle management tool for Java. A user of Maven
9075 specifies dependencies and plugins in a @file{pom.xml} file that Maven reads.
9076 When Maven does not have one of the dependencies or plugins in its repository,
9077 it will download them and use them to build the package.
9079 The maven build system ensures that maven will not try to download any
9080 dependency by running in offline mode. Maven will fail if a dependency is
9081 missing. Before running Maven, the @file{pom.xml} (and subprojects) are
9082 modified to specify the version of dependencies and plugins that match the
9083 versions available in the guix build environment. Dependencies and plugins
9084 must be installed in the fake maven repository at @file{lib/m2}, and are
9085 symlinked into a proper repository before maven is run. Maven is instructed
9086 to use that repository for the build and installs built artifacts there.
9087 Changed files are copied to the @file{lib/m2} directory of the package output.
9089 You can specify a @file{pom.xml} file with the @code{#:pom-file} argument,
9090 or let the build system use the default @file{pom.xml} file in the sources.
9092 In case you need to specify a dependency's version manually, you can use the
9093 @code{#:local-packages} argument. It takes an association list where the key
9094 is the groupId of the package and its value is an association list where the
9095 key is the artifactId of the package and its value is the version you want to
9096 override in the @file{pom.xml}.
9098 Some packages use dependencies or plugins that are not useful at runtime nor
9099 at build time in Guix. You can alter the @file{pom.xml} file to remove them
9100 using the @code{#:exclude} argument. Its value is an association list where
9101 the key is the groupId of the plugin or dependency you want to remove, and
9102 the value is a list of artifactId you want to remove.
9104 You can override the default @code{jdk} and @code{maven} packages with the
9105 corresponding argument, @code{#:jdk} and @code{#:maven}.
9107 The @code{#:maven-plugins} argument is a list of maven plugins used during
9108 the build, with the same format as the @code{inputs} fields of the package
9109 declaration. Its default value is @code{(default-maven-plugins)} which is
9113 @defvr {Scheme Variable} minetest-mod-build-system
9114 This variable is exported by @code{(guix build-system minetest)}. It
9115 implements a build procedure for @uref{https://www.minetest.net, Minetest}
9116 mods, which consists of copying Lua code, images and other resources to
9117 the location Minetest searches for mods. The build system also minimises
9118 PNG images and verifies that Minetest can load the mod without errors.
9121 @defvr {Scheme Variable} minify-build-system
9122 This variable is exported by @code{(guix build-system minify)}. It
9123 implements a minification procedure for simple JavaScript packages.
9125 It adds @code{uglify-js} to the set of inputs and uses it to compress
9126 all JavaScript files in the @file{src} directory. A different minifier
9127 package can be specified with the @code{#:uglify-js} parameter, but it
9128 is expected that the package writes the minified code to the standard
9131 When the input JavaScript files are not all located in the @file{src}
9132 directory, the parameter @code{#:javascript-files} can be used to
9133 specify a list of file names to feed to the minifier.
9136 @defvr {Scheme Variable} ocaml-build-system
9137 This variable is exported by @code{(guix build-system ocaml)}. It implements
9138 a build procedure for @uref{https://ocaml.org, OCaml} packages, which consists
9139 of choosing the correct set of commands to run for each package. OCaml
9140 packages can expect many different commands to be run. This build system will
9143 When the package has a @file{setup.ml} file present at the top-level, it will
9144 run @code{ocaml setup.ml -configure}, @code{ocaml setup.ml -build} and
9145 @code{ocaml setup.ml -install}. The build system will assume that this file
9146 was generated by @uref{http://oasis.forge.ocamlcore.org/, OASIS} and will take
9147 care of setting the prefix and enabling tests if they are not disabled. You
9148 can pass configure and build flags with the @code{#:configure-flags} and
9149 @code{#:build-flags}. The @code{#:test-flags} key can be passed to change the
9150 set of flags used to enable tests. The @code{#:use-make?} key can be used to
9151 bypass this system in the build and install phases.
9153 When the package has a @file{configure} file, it is assumed that it is a
9154 hand-made configure script that requires a different argument format than
9155 in the @code{gnu-build-system}. You can add more flags with the
9156 @code{#:configure-flags} key.
9158 When the package has a @file{Makefile} file (or @code{#:use-make?} is
9159 @code{#t}), it will be used and more flags can be passed to the build and
9160 install phases with the @code{#:make-flags} key.
9162 Finally, some packages do not have these files and use a somewhat standard
9163 location for its build system. In that case, the build system will run
9164 @code{ocaml pkg/pkg.ml} or @code{ocaml pkg/build.ml} and take care of
9165 providing the path to the required findlib module. Additional flags can
9166 be passed via the @code{#:build-flags} key. Install is taken care of by
9167 @command{opam-installer}. In this case, the @code{opam} package must
9168 be added to the @code{native-inputs} field of the package definition.
9170 Note that most OCaml packages assume they will be installed in the same
9171 directory as OCaml, which is not what we want in guix. In particular, they
9172 will install @file{.so} files in their module's directory, which is usually
9173 fine because it is in the OCaml compiler directory. In guix though, these
9174 libraries cannot be found and we use @env{CAML_LD_LIBRARY_PATH}. This
9175 variable points to @file{lib/ocaml/site-lib/stubslibs} and this is where
9176 @file{.so} libraries should be installed.
9179 @defvr {Scheme Variable} python-build-system
9180 This variable is exported by @code{(guix build-system python)}. It
9181 implements the more or less standard build procedure used by Python
9182 packages, which consists in running @code{python setup.py build} and
9183 then @code{python setup.py install --prefix=/gnu/store/@dots{}}.
9185 For packages that install stand-alone Python programs under @code{bin/},
9186 it takes care of wrapping these programs so that their
9187 @env{GUIX_PYTHONPATH} environment variable points to all the Python
9188 libraries they depend on.
9190 Which Python package is used to perform the build can be specified with
9191 the @code{#:python} parameter. This is a useful way to force a package
9192 to be built for a specific version of the Python interpreter, which
9193 might be necessary if the package is only compatible with a single
9194 interpreter version.
9196 By default guix calls @code{setup.py} under control of
9197 @code{setuptools}, much like @command{pip} does. Some packages are not
9198 compatible with setuptools (and pip), thus you can disable this by
9199 setting the @code{#:use-setuptools?} parameter to @code{#f}.
9201 If a @code{"python"} output is available, the package is installed into it
9202 instead of the default @code{"out"} output. This is useful for packages that
9203 include a Python package as only a part of the software, and thus want to
9204 combine the phases of @code{python-build-system} with another build system.
9205 Python bindings are a common usecase.
9209 @defvr {Scheme Variable} perl-build-system
9210 This variable is exported by @code{(guix build-system perl)}. It
9211 implements the standard build procedure for Perl packages, which either
9212 consists in running @code{perl Build.PL --prefix=/gnu/store/@dots{}},
9213 followed by @code{Build} and @code{Build install}; or in running
9214 @code{perl Makefile.PL PREFIX=/gnu/store/@dots{}}, followed by
9215 @code{make} and @code{make install}, depending on which of
9216 @code{Build.PL} or @code{Makefile.PL} is present in the package
9217 distribution. Preference is given to the former if both @code{Build.PL}
9218 and @code{Makefile.PL} exist in the package distribution. This
9219 preference can be reversed by specifying @code{#t} for the
9220 @code{#:make-maker?} parameter.
9222 The initial @code{perl Makefile.PL} or @code{perl Build.PL} invocation
9223 passes flags specified by the @code{#:make-maker-flags} or
9224 @code{#:module-build-flags} parameter, respectively.
9226 Which Perl package is used can be specified with @code{#:perl}.
9229 @defvr {Scheme Variable} renpy-build-system
9230 This variable is exported by @code{(guix build-system renpy)}. It implements
9231 the more or less standard build procedure used by Ren'py games, which consists
9232 of loading @code{#:game} once, thereby creating bytecode for it.
9234 It further creates a wrapper script in @code{bin/} and a desktop entry in
9235 @code{share/applications}, both of which can be used to launch the game.
9237 Which Ren'py package is used can be specified with @code{#:renpy}.
9238 Games can also be installed in outputs other than ``out'' by using
9242 @defvr {Scheme Variable} qt-build-system
9243 This variable is exported by @code{(guix build-system qt)}. It
9244 is intended for use with applications using Qt or KDE.
9246 This build system adds the following two phases to the ones defined by
9247 @code{cmake-build-system}:
9251 The phase @code{check-setup} prepares the environment for running
9252 the checks as commonly used by Qt test programs.
9253 For now this only sets some environment variables:
9254 @code{QT_QPA_PLATFORM=offscreen},
9255 @code{DBUS_FATAL_WARNINGS=0} and
9256 @code{CTEST_OUTPUT_ON_FAILURE=1}.
9258 This phase is added before the @code{check} phase.
9259 It's a separate phase to ease adjusting if necessary.
9262 The phase @code{qt-wrap}
9263 searches for Qt5 plugin paths, QML paths and some XDG in the inputs
9264 and output. In case some path is found, all programs in the output's
9265 @file{bin/}, @file{sbin/}, @file{libexec/} and @file{lib/libexec/} directories
9266 are wrapped in scripts defining the necessary environment variables.
9268 It is possible to exclude specific package outputs from that wrapping process
9269 by listing their names in the @code{#:qt-wrap-excluded-outputs} parameter.
9270 This is useful when an output is known not to contain any Qt binaries, and
9271 where wrapping would gratuitously add a dependency of that output on Qt, KDE,
9274 This phase is added after the @code{install} phase.
9278 @defvr {Scheme Variable} r-build-system
9279 This variable is exported by @code{(guix build-system r)}. It
9280 implements the build procedure used by @uref{https://r-project.org, R}
9281 packages, which essentially is little more than running @samp{R CMD
9282 INSTALL --library=/gnu/store/@dots{}} in an environment where
9283 @env{R_LIBS_SITE} contains the paths to all R package inputs. Tests are
9284 run after installation using the R function
9285 @code{tools::testInstalledPackage}.
9288 @defvr {Scheme Variable} rakudo-build-system
9289 This variable is exported by @code{(guix build-system rakudo)}. It
9290 implements the build procedure used by @uref{https://rakudo.org/,
9291 Rakudo} for @uref{https://perl6.org/, Perl6} packages. It installs the
9292 package to @code{/gnu/store/@dots{}/NAME-VERSION/share/perl6} and
9293 installs the binaries, library files and the resources, as well as wrap
9294 the files under the @code{bin/} directory. Tests can be skipped by
9295 passing @code{#f} to the @code{tests?} parameter.
9297 Which rakudo package is used can be specified with @code{rakudo}.
9298 Which perl6-tap-harness package used for the tests can be specified with
9299 @code{#:prove6} or removed by passing @code{#f} to the
9300 @code{with-prove6?} parameter.
9301 Which perl6-zef package used for tests and installing can be specified
9302 with @code{#:zef} or removed by passing @code{#f} to the
9303 @code{with-zef?} parameter.
9306 @defvr {Scheme Variable} rebar-build-system
9307 This variable is exported by @code{(guix build-system rebar)}. It
9308 implements a build procedure around @uref{https://rebar3.org,rebar3},
9309 a build system for programs written in the Erlang language.
9311 It adds both @code{rebar3} and the @code{erlang} to the set of inputs.
9312 Different packages can be specified with the @code{#:rebar} and
9313 @code{#:erlang} parameters, respectively.
9315 This build system is based on @code{gnu-build-system}, but with the
9316 following phases changed:
9321 This phase, after unpacking the source like the @code{gnu-build-system}
9322 does, checks for a file @code{contents.tar.gz} at the top-level of the
9323 source. If this file exists, it will be unpacked, too. This eases
9324 handling of package hosted at @uref{https://hex.pm/},
9325 the Erlang and Elixir package repository.
9329 There are no @code{bootstrap} and @code{configure} phase because erlang
9330 packages typically don’t need to be configured.
9333 This phase runs @code{rebar3 compile}
9334 with the flags listed in @code{#:rebar-flags}.
9337 Unless @code{#:tests? #f} is passed,
9338 this phase runs @code{rebar3 eunit},
9339 or some other target specified with @code{#:test-target},
9340 with the flags listed in @code{#:rebar-flags},
9343 This installs the files created in the @i{default} profile, or some
9344 other profile specified with @code{#:install-profile}.
9349 @defvr {Scheme Variable} texlive-build-system
9350 This variable is exported by @code{(guix build-system texlive)}. It is
9351 used to build TeX packages in batch mode with a specified engine. The
9352 build system sets the @env{TEXINPUTS} variable to find all TeX source
9353 files in the inputs.
9355 By default it runs @code{luatex} on all files ending on @code{ins}. A
9356 different engine and format can be specified with the
9357 @code{#:tex-format} argument. Different build targets can be specified
9358 with the @code{#:build-targets} argument, which expects a list of file
9359 names. The build system adds only @code{texlive-bin} and
9360 @code{texlive-latex-base} (both from @code{(gnu packages tex}) to the
9361 inputs. Both can be overridden with the arguments @code{#:texlive-bin}
9362 and @code{#:texlive-latex-base}, respectively.
9364 The @code{#:tex-directory} parameter tells the build system where to
9365 install the built files under the texmf tree.
9368 @defvr {Scheme Variable} ruby-build-system
9369 This variable is exported by @code{(guix build-system ruby)}. It
9370 implements the RubyGems build procedure used by Ruby packages, which
9371 involves running @code{gem build} followed by @code{gem install}.
9373 The @code{source} field of a package that uses this build system
9374 typically references a gem archive, since this is the format that Ruby
9375 developers use when releasing their software. The build system unpacks
9376 the gem archive, potentially patches the source, runs the test suite,
9377 repackages the gem, and installs it. Additionally, directories and
9378 tarballs may be referenced to allow building unreleased gems from Git or
9379 a traditional source release tarball.
9381 Which Ruby package is used can be specified with the @code{#:ruby}
9382 parameter. A list of additional flags to be passed to the @command{gem}
9383 command can be specified with the @code{#:gem-flags} parameter.
9386 @defvr {Scheme Variable} waf-build-system
9387 This variable is exported by @code{(guix build-system waf)}. It
9388 implements a build procedure around the @code{waf} script. The common
9389 phases---@code{configure}, @code{build}, and @code{install}---are
9390 implemented by passing their names as arguments to the @code{waf}
9393 The @code{waf} script is executed by the Python interpreter. Which
9394 Python package is used to run the script can be specified with the
9395 @code{#:python} parameter.
9398 @defvr {Scheme Variable} scons-build-system
9399 This variable is exported by @code{(guix build-system scons)}. It
9400 implements the build procedure used by the SCons software construction
9401 tool. This build system runs @code{scons} to build the package,
9402 @code{scons test} to run tests, and then @code{scons install} to install
9405 Additional flags to be passed to @code{scons} can be specified with the
9406 @code{#:scons-flags} parameter. The default build and install targets
9407 can be overridden with @code{#:build-targets} and
9408 @code{#:install-targets} respectively. The version of Python used to
9409 run SCons can be specified by selecting the appropriate SCons package
9410 with the @code{#:scons} parameter.
9413 @defvr {Scheme Variable} haskell-build-system
9414 This variable is exported by @code{(guix build-system haskell)}. It
9415 implements the Cabal build procedure used by Haskell packages, which
9416 involves running @code{runhaskell Setup.hs configure
9417 --prefix=/gnu/store/@dots{}} and @code{runhaskell Setup.hs build}.
9418 Instead of installing the package by running @code{runhaskell Setup.hs
9419 install}, to avoid trying to register libraries in the read-only
9420 compiler store directory, the build system uses @code{runhaskell
9421 Setup.hs copy}, followed by @code{runhaskell Setup.hs register}. In
9422 addition, the build system generates the package documentation by
9423 running @code{runhaskell Setup.hs haddock}, unless @code{#:haddock? #f}
9424 is passed. Optional Haddock parameters can be passed with the help of
9425 the @code{#:haddock-flags} parameter. If the file @code{Setup.hs} is
9426 not found, the build system looks for @code{Setup.lhs} instead.
9428 Which Haskell compiler is used can be specified with the @code{#:haskell}
9429 parameter which defaults to @code{ghc}.
9432 @defvr {Scheme Variable} dub-build-system
9433 This variable is exported by @code{(guix build-system dub)}. It
9434 implements the Dub build procedure used by D packages, which
9435 involves running @code{dub build} and @code{dub run}.
9436 Installation is done by copying the files manually.
9438 Which D compiler is used can be specified with the @code{#:ldc}
9439 parameter which defaults to @code{ldc}.
9442 @anchor{emacs-build-system}
9443 @defvr {Scheme Variable} emacs-build-system
9444 This variable is exported by @code{(guix build-system emacs)}. It
9445 implements an installation procedure similar to the packaging system
9446 of Emacs itself (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
9448 It first creates the @code{@code{package}-autoloads.el} file, then it
9449 byte compiles all Emacs Lisp files. Differently from the Emacs
9450 packaging system, the Info documentation files are moved to the standard
9451 documentation directory and the @file{dir} file is deleted. The Elisp
9452 package files are installed directly under @file{share/emacs/site-lisp}.
9455 @defvr {Scheme Variable} font-build-system
9456 This variable is exported by @code{(guix build-system font)}. It
9457 implements an installation procedure for font packages where upstream
9458 provides pre-compiled TrueType, OpenType, etc.@: font files that merely
9459 need to be copied into place. It copies font files to standard
9460 locations in the output directory.
9463 @defvr {Scheme Variable} meson-build-system
9464 This variable is exported by @code{(guix build-system meson)}. It
9465 implements the build procedure for packages that use
9466 @url{https://mesonbuild.com, Meson} as their build system.
9468 It adds both Meson and @uref{https://ninja-build.org/, Ninja} to the set
9469 of inputs, and they can be changed with the parameters @code{#:meson}
9470 and @code{#:ninja} if needed.
9472 This build system is an extension of @code{gnu-build-system}, but with the
9473 following phases changed to some specific for Meson:
9478 The phase runs @code{meson} with the flags specified in
9479 @code{#:configure-flags}. The flag @option{--buildtype} is always set to
9480 @code{debugoptimized} unless something else is specified in
9481 @code{#:build-type}.
9484 The phase runs @code{ninja} to build the package in parallel by default, but
9485 this can be changed with @code{#:parallel-build?}.
9488 The phase runs @samp{meson test} with a base set of options that cannot
9489 be overridden. This base set of options can be extended via the
9490 @code{#:test-options} argument, for example to select or skip a specific
9494 The phase runs @code{ninja install} and can not be changed.
9497 Apart from that, the build system also adds the following phases:
9502 This phase ensures that all binaries can find the libraries they need.
9503 It searches for required libraries in subdirectories of the package
9504 being built, and adds those to @code{RUNPATH} where needed. It also
9505 removes references to libraries left over from the build phase by
9506 @code{meson}, such as test dependencies, that aren't actually required
9507 for the program to run.
9509 @item glib-or-gtk-wrap
9510 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
9511 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
9513 @item glib-or-gtk-compile-schemas
9514 This phase is the phase provided by @code{glib-or-gtk-build-system}, and it
9515 is not enabled by default. It can be enabled with @code{#:glib-or-gtk?}.
9519 @defvr {Scheme Variable} linux-module-build-system
9520 @code{linux-module-build-system} allows building Linux kernel modules.
9522 @cindex build phases
9523 This build system is an extension of @code{gnu-build-system}, but with the
9524 following phases changed:
9529 This phase configures the environment so that the Linux kernel's Makefile
9530 can be used to build the external kernel module.
9533 This phase uses the Linux kernel's Makefile in order to build the external
9537 This phase uses the Linux kernel's Makefile in order to install the external
9541 It is possible and useful to specify the Linux kernel to use for building
9542 the module (in the @code{arguments} form of a package using the
9543 @code{linux-module-build-system}, use the key @code{#:linux} to specify it).
9546 @defvr {Scheme Variable} node-build-system
9547 This variable is exported by @code{(guix build-system node)}. It
9548 implements the build procedure used by @uref{https://nodejs.org,
9549 Node.js}, which implements an approximation of the @code{npm install}
9550 command, followed by an @code{npm test} command.
9552 Which Node.js package is used to interpret the @code{npm} commands can
9553 be specified with the @code{#:node} parameter which defaults to
9557 Lastly, for packages that do not need anything as sophisticated, a
9558 ``trivial'' build system is provided. It is trivial in the sense that
9559 it provides basically no support: it does not pull any implicit inputs,
9560 and does not have a notion of build phases.
9562 @defvr {Scheme Variable} trivial-build-system
9563 This variable is exported by @code{(guix build-system trivial)}.
9565 This build system requires a @code{#:builder} argument. This argument
9566 must be a Scheme expression that builds the package output(s)---as
9567 with @code{build-expression->derivation} (@pxref{Derivations,
9568 @code{build-expression->derivation}}).
9571 @defvr {Scheme Variable} channel-build-system
9572 This variable is exported by @code{(guix build-system channel)}.
9574 This build system is meant primarily for internal use. A package using
9575 this build system must have a channel specification as its @code{source}
9576 field (@pxref{Channels}); alternatively, its source can be a directory
9577 name, in which case an additional @code{#:commit} argument must be
9578 supplied to specify the commit being built (a hexadecimal string).
9580 The resulting package is a Guix instance of the given channel, similar
9581 to how @command{guix time-machine} would build it.
9585 @section Build Phases
9587 @cindex build phases, for packages
9588 Almost all package build systems implement a notion @dfn{build phases}:
9589 a sequence of actions that the build system executes, when you build the
9590 package, leading to the installed byproducts in the store. A notable
9591 exception is the ``bare-bones'' @code{trivial-build-system}
9592 (@pxref{Build Systems}).
9594 As discussed in the previous section, those build systems provide a
9595 standard list of phases. For @code{gnu-build-system}, the main build
9596 phases are the following:
9600 Define search path environment variables for all the input packages,
9601 including @env{PATH} (@pxref{Search Paths}).
9604 Unpack the source tarball, and change the current directory to the
9605 extracted source tree. If the source is actually a directory, copy it
9606 to the build tree, and enter that directory.
9608 @item patch-source-shebangs
9609 Patch shebangs encountered in source files so they refer to the right
9610 store file names. For instance, this changes @code{#!/bin/sh} to
9611 @code{#!/gnu/store/@dots{}-bash-4.3/bin/sh}.
9614 Run the @file{configure} script with a number of default options, such
9615 as @option{--prefix=/gnu/store/@dots{}}, as well as the options specified
9616 by the @code{#:configure-flags} argument.
9619 Run @code{make} with the list of flags specified with
9620 @code{#:make-flags}. If the @code{#:parallel-build?} argument is true
9621 (the default), build with @code{make -j}.
9624 Run @code{make check}, or some other target specified with
9625 @code{#:test-target}, unless @code{#:tests? #f} is passed. If the
9626 @code{#:parallel-tests?} argument is true (the default), run @code{make
9630 Run @code{make install} with the flags listed in @code{#:make-flags}.
9632 @item patch-shebangs
9633 Patch shebangs on the installed executable files.
9636 Strip debugging symbols from ELF files (unless @code{#:strip-binaries?}
9637 is false), copying them to the @code{debug} output when available
9638 (@pxref{Installing Debugging Files}).
9640 @cindex RUNPATH, validation
9641 @anchor{phase-validate-runpath}
9642 @item validate-runpath
9643 Validate the @code{RUNPATH} of ELF binaries, unless
9644 @code{#:validate-runpath?} is false (@pxref{Build Systems}).
9646 This validation step consists in making sure that all the shared
9647 libraries needed by an ELF binary, which are listed as @code{DT_NEEDED}
9648 entries in its @code{PT_DYNAMIC} segment, appear in the
9649 @code{DT_RUNPATH} entry of that binary. In other words, it ensures that
9650 running or using those binaries will not result in a ``file not found''
9651 error at run time. @xref{Options, @option{-rpath},, ld, The GNU
9652 Linker}, for more information on @code{RUNPATH}.
9656 Other build systems have similar phases, with some variations. For
9657 example, @code{cmake-build-system} has same-named phases but its
9658 @code{configure} phases runs @code{cmake} instead of @code{./configure}.
9659 Others, such as @code{python-build-system}, have a wholly different list
9660 of standard phases. All this code runs on the @dfn{build side}: it is
9661 evaluated when you actually build the package, in a dedicated build
9662 process spawned by the build daemon (@pxref{Invoking guix-daemon}).
9664 Build phases are represented as association lists or ``alists''
9665 (@pxref{Association Lists,,, guile, GNU Guile Reference Manual}) where
9666 each key is a symbol for the name of the phase and the associated value
9667 is a procedure that accepts an arbitrary number of arguments. By
9668 convention, those procedures receive information about the build in the
9669 form of @dfn{keyword parameters}, which they can use or ignore.
9671 @vindex %standard-phases
9672 For example, here is how @code{(guix build gnu-build-system)} defines
9673 @code{%standard-phases}, the variable holding its alist of build
9674 phases@footnote{We present a simplified view of those build phases, but
9675 do take a look at @code{(guix build gnu-build-system)} to see all the
9679 ;; The build phases of 'gnu-build-system'.
9681 (define* (unpack #:key source #:allow-other-keys)
9682 ;; Extract the source tarball.
9683 (invoke "tar" "xvf" source))
9685 (define* (configure #:key outputs #:allow-other-keys)
9686 ;; Run the 'configure' script. Install to output "out".
9687 (let ((out (assoc-ref outputs "out")))
9688 (invoke "./configure"
9689 (string-append "--prefix=" out))))
9691 (define* (build #:allow-other-keys)
9695 (define* (check #:key (test-target "check") (tests? #true)
9697 ;; Run the test suite.
9699 (invoke "make" test-target)
9700 (display "test suite not run\n")))
9702 (define* (install #:allow-other-keys)
9703 ;; Install files to the prefix 'configure' specified.
9704 (invoke "make" "install"))
9706 (define %standard-phases
9707 ;; The list of standard phases (quite a few are omitted
9708 ;; for brevity). Each element is a symbol/procedure pair.
9709 (list (cons 'unpack unpack)
9710 (cons 'configure configure)
9713 (cons 'install install)))
9716 This shows how @code{%standard-phases} is defined as a list of
9717 symbol/procedure pairs (@pxref{Pairs,,, guile, GNU Guile Reference
9718 Manual}). The first pair associates the @code{unpack} procedure with
9719 the @code{unpack} symbol---a name; the second pair defines the
9720 @code{configure} phase similarly, and so on. When building a package
9721 that uses @code{gnu-build-system} with its default list of phases, those
9722 phases are executed sequentially. You can see the name of each phase
9723 started and completed in the build log of packages that you build.
9725 Let's now look at the procedures themselves. Each one is defined with
9726 @code{define*}: @code{#:key} lists keyword parameters the procedure
9727 accepts, possibly with a default value, and @code{#:allow-other-keys}
9728 specifies that other keyword parameters are ignored (@pxref{Optional
9729 Arguments,,, guile, GNU Guile Reference Manual}).
9731 The @code{unpack} procedure honors the @code{source} parameter, which
9732 the build system uses to pass the file name of the source tarball (or
9733 version control checkout), and it ignores other parameters. The
9734 @code{configure} phase only cares about the @code{outputs} parameter, an
9735 alist mapping package output names to their store file name
9736 (@pxref{Packages with Multiple Outputs}). It extracts the file name of
9737 for @code{out}, the default output, and passes it to
9738 @command{./configure} as the installation prefix, meaning that
9739 @command{make install} will eventually copy all the files in that
9740 directory (@pxref{Configuration, configuration and makefile
9741 conventions,, standards, GNU Coding Standards}). @code{build} and
9742 @code{install} ignore all their arguments. @code{check} honors the
9743 @code{test-target} argument, which specifies the name of the Makefile
9744 target to run tests; it prints a message and skips tests when
9745 @code{tests?} is false.
9747 @cindex build phases, customizing
9748 The list of phases used for a particular package can be changed with the
9749 @code{#:phases} parameter of the build system. Changing the set of
9750 build phases boils down to building a new alist of phases based on the
9751 @code{%standard-phases} alist described above. This can be done with
9752 standard alist procedures such as @code{alist-delete} (@pxref{SRFI-1
9753 Association Lists,,, guile, GNU Guile Reference Manual}); however, it is
9754 more convenient to do so with @code{modify-phases} (@pxref{Build
9755 Utilities, @code{modify-phases}}).
9757 Here is an example of a package definition that removes the
9758 @code{configure} phase of @code{%standard-phases} and inserts a new
9759 phase before the @code{build} phase, called
9760 @code{set-prefix-in-makefile}:
9763 (define-public example
9766 ;; other fields omitted
9767 (build-system gnu-build-system)
9769 '(#:phases (modify-phases %standard-phases
9771 (add-before 'build 'set-prefix-in-makefile
9772 (lambda* (#:key outputs #:allow-other-keys)
9773 ;; Modify the makefile so that its
9774 ;; 'PREFIX' variable points to "out".
9775 (let ((out (assoc-ref outputs "out")))
9776 (substitute* "Makefile"
9778 (string-append "PREFIX = "
9782 The new phase that is inserted is written as an anonymous procedure,
9783 introduced with @code{lambda*}; it honors the @code{outputs} parameter
9784 we have seen before. @xref{Build Utilities}, for more about the helpers
9785 used by this phase, and for more examples of @code{modify-phases}.
9787 @cindex code staging
9788 @cindex staging, of code
9789 Keep in mind that build phases are code evaluated at the time the
9790 package is actually built. This explains why the whole
9791 @code{modify-phases} expression above is quoted (it comes after the
9792 @code{'} or apostrophe): it is @dfn{staged} for later execution.
9793 @xref{G-Expressions}, for an explanation of code staging and the
9794 @dfn{code strata} involved.
9796 @node Build Utilities
9797 @section Build Utilities
9799 As soon as you start writing non-trivial package definitions
9800 (@pxref{Defining Packages}) or other build actions
9801 (@pxref{G-Expressions}), you will likely start looking for helpers for
9802 ``shell-like'' actions---creating directories, copying and deleting
9803 files recursively, manipulating build phases, and so on. The
9804 @code{(guix build utils)} module provides such utility procedures.
9806 Most build systems load @code{(guix build utils)} (@pxref{Build
9807 Systems}). Thus, when writing custom build phases for your package
9808 definitions, you can usually assume those procedures are in scope.
9810 When writing G-expressions, you can import @code{(guix build utils)} on
9811 the ``build side'' using @code{with-imported-modules} and then put it in
9812 scope with the @code{use-modules} form (@pxref{Using Guile Modules,,,
9813 guile, GNU Guile Reference Manual}):
9816 (with-imported-modules '((guix build utils)) ;import it
9817 (computed-file "empty-tree"
9820 (use-modules (guix build utils))
9822 ;; Happily use its 'mkdir-p' procedure.
9823 (mkdir-p (string-append #$output "/a/b/c")))))
9826 The remainder of this section is the reference for most of the utility
9827 procedures provided by @code{(guix build utils)}.
9829 @c TODO Document what's missing.
9831 @subsection Dealing with Store File Names
9833 This section documents procedures that deal with store file names.
9835 @deffn {Scheme Procedure} %store-directory
9836 Return the directory name of the store.
9839 @deffn {Scheme Procedure} store-file-name? @var{file}
9840 Return true if @var{file} is in the store.
9843 @deffn {Scheme Procedure} strip-store-file-name @var{file}
9844 Strip the @file{/gnu/store} and hash from @var{file}, a store file name.
9845 The result is typically a @code{"@var{package}-@var{version}"} string.
9848 @deffn {Scheme Procedure} package-name->name+version @var{name}
9849 Given @var{name}, a package name like @code{"foo-0.9.1b"}, return two
9850 values: @code{"foo"} and @code{"0.9.1b"}. When the version part is
9851 unavailable, @var{name} and @code{#f} are returned. The first hyphen
9852 followed by a digit is considered to introduce the version part.
9855 @subsection File Types
9857 The procedures below deal with files and file types.
9859 @deffn {Scheme Procedure} directory-exists? @var{dir}
9860 Return @code{#t} if @var{dir} exists and is a directory.
9863 @deffn {Scheme Procedure} executable-file? @var{file}
9864 Return @code{#t} if @var{file} exists and is executable.
9867 @deffn {Scheme Procedure} symbolic-link? @var{file}
9868 Return @code{#t} if @var{file} is a symbolic link (aka. a ``symlink'').
9871 @deffn {Scheme Procedure} elf-file? @var{file}
9872 @deffnx {Scheme Procedure} ar-file? @var{file}
9873 @deffnx {Scheme Procedure} gzip-file? @var{file}
9874 Return @code{#t} if @var{file} is, respectively, an ELF file, an
9875 @code{ar} archive (such as a @file{.a} static library), or a gzip file.
9878 @deffn {Scheme Procedure} reset-gzip-timestamp @var{file} [#:keep-mtime? #t]
9879 If @var{file} is a gzip file, reset its embedded timestamp (as with
9880 @command{gzip --no-name}) and return true. Otherwise return @code{#f}.
9881 When @var{keep-mtime?} is true, preserve @var{file}'s modification time.
9884 @subsection File Manipulation
9886 The following procedures and macros help create, modify, and delete
9887 files. They provide functionality comparable to common shell utilities
9888 such as @command{mkdir -p}, @command{cp -r}, @command{rm -r}, and
9889 @command{sed}. They complement Guile's extensive, but low-level, file
9890 system interface (@pxref{POSIX,,, guile, GNU Guile Reference Manual}).
9892 @deffn {Scheme Syntax} with-directory-excursion @var{directory} @var{body}@dots{}
9893 Run @var{body} with @var{directory} as the process's current directory.
9895 Essentially, this macro changes the current directory to @var{directory}
9896 before evaluating @var{body}, using @code{chdir} (@pxref{Processes,,,
9897 guile, GNU Guile Reference Manual}). It changes back to the initial
9898 directory when the dynamic extent of @var{body} is left, be it @i{via}
9899 normal procedure return or @i{via} a non-local exit such as an
9903 @deffn {Scheme Procedure} mkdir-p @var{dir}
9904 Create directory @var{dir} and all its ancestors.
9907 @deffn {Scheme Procedure} install-file @var{file} @var{directory}
9908 Create @var{directory} if it does not exist and copy @var{file} in there
9909 under the same name.
9912 @deffn {Scheme Procedure} make-file-writable @var{file}
9913 Make @var{file} writable for its owner.
9916 @deffn {Scheme Procedure} copy-recursively @var{source} @var{destination} @
9917 [#:log (current-output-port)] [#:follow-symlinks? #f] @
9918 [#:copy-file copy-file] [#:keep-mtime? #f] [#:keep-permissions? #t]
9919 Copy @var{source} directory to @var{destination}. Follow symlinks if
9920 @var{follow-symlinks?} is true; otherwise, just preserve them. Call
9921 @var{copy-file} to copy regular files. When @var{keep-mtime?} is true,
9922 keep the modification time of the files in @var{source} on those of
9923 @var{destination}. When @var{keep-permissions?} is true, preserve file
9924 permissions. Write verbose output to the @var{log} port.
9927 @deffn {Scheme Procedure} delete-file-recursively @var{dir} @
9928 [#:follow-mounts? #f]
9929 Delete @var{dir} recursively, like @command{rm -rf}, without following
9930 symlinks. Don't follow mount points either, unless @var{follow-mounts?}
9931 is true. Report but ignore errors.
9934 @deffn {Scheme Syntax} substitute* @var{file} @
9935 ((@var{regexp} @var{match-var}@dots{}) @var{body}@dots{}) @dots{}
9936 Substitute @var{regexp} in @var{file} by the string returned by
9937 @var{body}. @var{body} is evaluated with each @var{match-var} bound to
9938 the corresponding positional regexp sub-expression. For example:
9944 (("foo([a-z]+)bar(.*)$" all letters end)
9945 (string-append "baz" letters end)))
9948 Here, anytime a line of @var{file} contains @code{hello}, it is replaced
9949 by @code{good morning}. Anytime a line of @var{file} matches the second
9950 regexp, @code{all} is bound to the complete match, @code{letters} is bound
9951 to the first sub-expression, and @code{end} is bound to the last one.
9953 When one of the @var{match-var} is @code{_}, no variable is bound to the
9954 corresponding match substring.
9956 Alternatively, @var{file} may be a list of file names, in which case
9957 they are all subject to the substitutions.
9959 Be careful about using @code{$} to match the end of a line; by itself it
9960 won't match the terminating newline of a line.
9963 @subsection File Search
9965 @cindex file, searching
9966 This section documents procedures to search and filter files.
9968 @deffn {Scheme Procedure} file-name-predicate @var{regexp}
9969 Return a predicate that returns true when passed a file name whose base
9970 name matches @var{regexp}.
9973 @deffn {Scheme Procedure} find-files @var{dir} [@var{pred}] @
9974 [#:stat lstat] [#:directories? #f] [#:fail-on-error? #f]
9975 Return the lexicographically sorted list of files under @var{dir} for
9976 which @var{pred} returns true. @var{pred} is passed two arguments: the
9977 absolute file name, and its stat buffer; the default predicate always
9978 returns true. @var{pred} can also be a regular expression, in which
9979 case it is equivalent to @code{(file-name-predicate @var{pred})}.
9980 @var{stat} is used to obtain file information; using @code{lstat} means
9981 that symlinks are not followed. If @var{directories?} is true, then
9982 directories will also be included. If @var{fail-on-error?} is true,
9983 raise an exception upon error.
9986 Here are a few examples where we assume that the current directory is
9987 the root of the Guix source tree:
9990 ;; List all the regular files in the current directory.
9992 @result{} ("./.dir-locals.el" "./.gitignore" @dots{})
9994 ;; List all the .scm files under gnu/services.
9995 (find-files "gnu/services" "\\.scm$")
9996 @result{} ("gnu/services/admin.scm" "gnu/services/audio.scm" @dots{})
9998 ;; List ar files in the current directory.
9999 (find-files "." (lambda (file stat) (ar-file? file)))
10000 @result{} ("./libformat.a" "./libstore.a" @dots{})
10003 @deffn {Scheme Procedure} which @var{program}
10004 Return the complete file name for @var{program} as found in
10005 @code{$PATH}, or @code{#f} if @var{program} could not be found.
10008 @deffn {Scheme Procedure} search-input-file @var{inputs} @var{name}
10009 @deffnx {Scheme Procedure} search-input-directory @var{inputs} @var{name}
10010 Return the complete file name for @var{name} as found in @var{inputs};
10011 @code{search-input-file} searches for a regular file and
10012 @code{search-input-directory} searches for a directory. If @var{name}
10013 could not be found, an exception is raised.
10015 Here, @var{inputs} must be an association list like @code{inputs} and
10016 @code{native-inputs} as available to build phases (@pxref{Build
10020 Here is a (simplified) example of how @code{search-input-file} is used
10021 in a build phase of the @code{wireguard-tools} package:
10024 (add-after 'install 'wrap-wg-quick
10025 (lambda* (#:key inputs outputs #:allow-other-keys)
10026 (let ((coreutils (string-append (assoc-ref inputs "coreutils")
10028 (wrap-program (search-input-file outputs "bin/wg-quick")
10029 #:sh (search-input-file inputs "bin/bash")
10030 `("PATH" ":" prefix ,(list coreutils))))))
10033 @subsection Program Invocation
10035 @cindex program invocation, from Scheme
10036 @cindex invoking programs, from Scheme
10037 You'll find handy procedures to spawn processes in this module,
10038 essentially convenient wrappers around Guile's @code{system*}
10039 (@pxref{Processes, @code{system*},, guile, GNU Guile Reference Manual}).
10041 @deffn {Scheme Procedure} invoke @var{program} @var{args}@dots{}
10042 Invoke @var{program} with the given @var{args}. Raise an
10043 @code{&invoke-error} exception if the exit code is non-zero; otherwise
10046 The advantage compared to @code{system*} is that you do not need to
10047 check the return value. This reduces boilerplate in shell-script-like
10048 snippets for instance in package build phases.
10051 @deffn {Scheme Procedure} invoke-error? @var{c}
10052 Return true if @var{c} is an @code{&invoke-error} condition.
10055 @deffn {Scheme Procedure} invoke-error-program @var{c}
10056 @deffnx {Scheme Procedure} invoke-error-arguments @var{c}
10057 @deffnx {Scheme Procedure} invoke-error-exit-status @var{c}
10058 @deffnx {Scheme Procedure} invoke-error-term-signal @var{c}
10059 @deffnx {Scheme Procedure} invoke-error-stop-signal @var{c}
10060 Access specific fields of @var{c}, an @code{&invoke-error} condition.
10063 @deffn {Scheme Procedure} report-invoke-error @var{c} [@var{port}]
10064 Report to @var{port} (by default the current error port) about @var{c},
10065 an @code{&invoke-error} condition, in a human-friendly way.
10067 Typical usage would look like this:
10070 (use-modules (srfi srfi-34) ;for 'guard'
10071 (guix build utils))
10073 (guard (c ((invoke-error? c)
10074 (report-invoke-error c)))
10075 (invoke "date" "--imaginary-option"))
10077 @print{} command "date" "--imaginary-option" failed with status 1
10081 @deffn {Scheme Procedure} invoke/quiet @var{program} @var{args}@dots{}
10082 Invoke @var{program} with @var{args} and capture @var{program}'s
10083 standard output and standard error. If @var{program} succeeds, print
10084 nothing and return the unspecified value; otherwise, raise a
10085 @code{&message} error condition that includes the status code and the
10086 output of @var{program}.
10091 (use-modules (srfi srfi-34) ;for 'guard'
10092 (srfi srfi-35) ;for 'message-condition?'
10093 (guix build utils))
10095 (guard (c ((message-condition? c)
10096 (display (condition-message c))))
10097 (invoke/quiet "date") ;all is fine
10098 (invoke/quiet "date" "--imaginary-option"))
10100 @print{} 'date --imaginary-option' exited with status 1; output follows:
10102 date: unrecognized option '--imaginary-option'
10103 Try 'date --help' for more information.
10107 @subsection Build Phases
10109 @cindex build phases
10110 The @code{(guix build utils)} also contains tools to manipulate build
10111 phases as used by build systems (@pxref{Build Systems}). Build phases
10112 are represented as association lists or ``alists'' (@pxref{Association
10113 Lists,,, guile, GNU Guile Reference Manual}) where each key is a symbol
10114 naming the phase and the associated value is a procedure (@pxref{Build
10117 Guile core and the @code{(srfi srfi-1)} module both provide tools to
10118 manipulate alists. The @code{(guix build utils)} module complements
10119 those with tools written with build phases in mind.
10121 @cindex build phases, modifying
10122 @deffn {Scheme Syntax} modify-phases @var{phases} @var{clause}@dots{}
10123 Modify @var{phases} sequentially as per each @var{clause}, which may
10124 have one of the following forms:
10127 (delete @var{old-phase-name})
10128 (replace @var{old-phase-name} @var{new-phase})
10129 (add-before @var{old-phase-name} @var{new-phase-name} @var{new-phase})
10130 (add-after @var{old-phase-name} @var{new-phase-name} @var{new-phase})
10133 Where every @var{phase-name} above is an expression evaluating to a
10134 symbol, and @var{new-phase} an expression evaluating to a procedure.
10137 The example below is taken from the definition of the @code{grep}
10138 package. It adds a phase to run after the @code{install} phase, called
10139 @code{fix-egrep-and-fgrep}. That phase is a procedure (@code{lambda*}
10140 is for anonymous procedures) that takes a @code{#:outputs} keyword
10141 argument and ignores extra keyword arguments (@pxref{Optional
10142 Arguments,,, guile, GNU Guile Reference Manual}, for more on
10143 @code{lambda*} and optional and keyword arguments.) The phase uses
10144 @code{substitute*} to modify the installed @file{egrep} and @file{fgrep}
10145 scripts so that they refer to @code{grep} by its absolute file name:
10148 (modify-phases %standard-phases
10149 (add-after 'install 'fix-egrep-and-fgrep
10150 ;; Patch 'egrep' and 'fgrep' to execute 'grep' via its
10151 ;; absolute file name instead of searching for it in $PATH.
10152 (lambda* (#:key outputs #:allow-other-keys)
10153 (let* ((out (assoc-ref outputs "out"))
10154 (bin (string-append out "/bin")))
10155 (substitute* (list (string-append bin "/egrep")
10156 (string-append bin "/fgrep"))
10158 (string-append "exec " bin "/grep")))))))
10161 In the example below, phases are modified in two ways: the standard
10162 @code{configure} phase is deleted, presumably because the package does
10163 not have a @file{configure} script or anything similar, and the default
10164 @code{install} phase is replaced by one that manually copies the
10165 executable files to be installed:
10168 (modify-phases %standard-phases
10169 (delete 'configure) ;no 'configure' script
10171 (lambda* (#:key outputs #:allow-other-keys)
10172 ;; The package's Makefile doesn't provide an "install"
10173 ;; rule so do it by ourselves.
10174 (let ((bin (string-append (assoc-ref outputs "out")
10176 (install-file "footswitch" bin)
10177 (install-file "scythe" bin)))))
10180 @c TODO: Add more examples.
10182 @subsection Wrappers
10184 @cindex program wrappers
10185 @cindex wrapping programs
10186 It is not unusual for a command to require certain environment variables
10187 to be set for proper functioning, typically search paths (@pxref{Search
10188 Paths}). Failing to do that, the command might fail to find files or
10189 other commands it relies on, or it might pick the ``wrong''
10190 ones---depending on the environment in which it runs. Examples include:
10194 a shell script that assumes all the commands it uses are in @env{PATH};
10197 a Guile program that assumes all its modules are in @env{GUILE_LOAD_PATH}
10198 and @env{GUILE_LOAD_COMPILED_PATH};
10201 a Qt application that expects to find certain plugins in
10202 @env{QT_PLUGIN_PATH}.
10205 For a package writer, the goal is to make sure commands always work the
10206 same rather than depend on some external settings. One way to achieve
10207 that is to @dfn{wrap} commands in a thin script that sets those
10208 environment variables, thereby ensuring that those run-time dependencies
10209 are always found. The wrapper would be used to set @env{PATH},
10210 @env{GUILE_LOAD_PATH}, or @env{QT_PLUGIN_PATH} in the examples above.
10212 To ease that task, the @code{(guix build utils)} module provides a
10213 couple of helpers to wrap commands.
10215 @deffn {Scheme Procedure} wrap-program @var{program} @
10216 [#:sh @var{sh}] [#:rest @var{variables}]
10217 Make a wrapper for @var{program}. @var{variables} should look like this:
10220 '(@var{variable} @var{delimiter} @var{position} @var{list-of-directories})
10223 where @var{delimiter} is optional. @code{:} will be used if
10224 @var{delimiter} is not given.
10226 For example, this call:
10229 (wrap-program "foo"
10230 '("PATH" ":" = ("/gnu/.../bar/bin"))
10231 '("CERT_PATH" suffix ("/gnu/.../baz/certs"
10235 will copy @file{foo} to @file{.foo-real} and create the file @file{foo}
10236 with the following contents:
10239 #!location/of/bin/bash
10240 export PATH="/gnu/.../bar/bin"
10241 export CERT_PATH="$CERT_PATH$@{CERT_PATH:+:@}/gnu/.../baz/certs:/qux/certs"
10242 exec -a $0 location/of/.foo-real "$@@"
10245 If @var{program} has previously been wrapped by @code{wrap-program}, the
10246 wrapper is extended with definitions for @var{variables}. If it is not,
10247 @var{sh} will be used as the interpreter.
10250 @deffn {Scheme Procedure} wrap-script @var{program} @
10251 [#:guile @var{guile}] [#:rest @var{variables}]
10252 Wrap the script @var{program} such that @var{variables} are set first.
10253 The format of @var{variables} is the same as in the @code{wrap-program}
10254 procedure. This procedure differs from @code{wrap-program} in that it
10255 does not create a separate shell script. Instead, @var{program} is
10256 modified directly by prepending a Guile script, which is interpreted as
10257 a comment in the script's language.
10259 Special encoding comments as supported by Python are recreated on the
10262 Note that this procedure can only be used once per file as Guile scripts are
10267 @section Search Paths
10269 @cindex search path
10270 Many programs and libraries look for input data in a @dfn{search path},
10271 a list of directories: shells like Bash look for executables in the
10272 command search path, a C compiler looks for @file{.h} files in its
10273 header search path, the Python interpreter looks for @file{.py}
10274 files in its search path, the spell checker has a search path for
10275 dictionaries, and so on.
10277 Search paths can usually be defined or overridden @i{via} environment
10278 variables (@pxref{Environment Variables,,, libc, The GNU C Library
10279 Reference Manual}). For example, the search paths mentioned above can
10280 be changed by defining the @env{PATH}, @env{C_INCLUDE_PATH},
10281 @env{PYTHONPATH} (or @env{GUIX_PYTHONPATH}), and @env{DICPATH}
10282 environment variables---you know, all these something-PATH variables
10283 that you need to get right or things ``won't be found''.
10285 You may have noticed from the command line that Guix ``knows'' which
10286 search path environment variables should be defined, and how. When you
10287 install packages in your default profile, the file
10288 @file{~/.guix-profile/etc/profile} is created, which you can ``source''
10289 from the shell to set those variables. Likewise, if you ask
10290 @command{guix shell} to create an environment containing Python and
10291 NumPy, a Python library, and if you pass it the @option{--search-paths}
10292 option, it will tell you about @env{PATH} and @env{GUIX_PYTHONPATH}
10293 (@pxref{Invoking guix shell}):
10296 $ guix shell python python-numpy --pure --search-paths
10297 export PATH="/gnu/store/@dots{}-profile/bin"
10298 export GUIX_PYTHONPATH="/gnu/store/@dots{}-profile/lib/python3.9/site-packages"
10301 When you omit @option{--search-paths}, it defines these environment
10302 variables right away, such that Python can readily find NumPy:
10305 $ guix shell python python-numpy -- python3
10306 Python 3.9.6 (default, Jan 1 1970, 00:00:01)
10307 [GCC 10.3.0] on linux
10308 Type "help", "copyright", "credits" or "license" for more information.
10310 >>> numpy.version.version
10314 For this to work, the definition of the @code{python} package
10315 @emph{declares} the search path it cares about and its associated
10316 environment variable, @env{GUIX_PYTHONPATH}. It looks like this:
10322 ;; some fields omitted...
10323 (native-search-paths
10324 (list (search-path-specification
10325 (variable "GUIX_PYTHONPATH")
10326 (files (list "lib/python/3.9/site-packages"))))))
10329 What this @code{native-search-paths} field says is that, when the
10330 @code{python} package is used, the @env{GUIX_PYTHONPATH} environment
10331 variable must be defined to include all the
10332 @file{lib/python/3.9/site-packages} sub-directories encountered in its
10333 environment. (The @code{native-} bit means that, if we are in a
10334 cross-compilation environment, only native inputs may be added to the
10335 search path; @pxref{package Reference, @code{search-paths}}.)
10336 In the NumPy example above, the profile where
10337 @code{python} appears contains exactly one such sub-directory, and
10338 @env{GUIX_PYTHONPATH} is set to that. When there are several
10339 @file{lib/python/3.9/site-packages}---this is the case in package build
10340 environments---they are all added to @env{GUIX_PYTHONPATH}, separated by
10344 Notice that @env{GUIX_PYTHONPATH} is specified as part of the definition
10345 of the @code{python} package, and @emph{not} as part of that of
10346 @code{python-numpy}. This is because this environment variable
10347 ``belongs'' to Python, not NumPy: Python actually reads the value of
10348 that variable and honors it.
10350 Corollary: if you create a profile that does not contain @code{python},
10351 @code{GUIX_PYTHONPATH} will @emph{not} be defined, even if it contains
10352 packages that provide @file{.py} files:
10355 $ guix shell python-numpy --search-paths --pure
10356 export PATH="/gnu/store/@dots{}-profile/bin"
10359 This makes a lot of sense if we look at this profile in isolation: no
10360 software in this profile would read @env{GUIX_PYTHONPATH}.
10363 Of course, there are many variations on that theme: some packages honor
10364 more than one search path, some use separators other than colon, some
10365 accumulate several directories in their search path, and so on. A more
10366 complex example is the search path of libxml2: the value of the
10367 @env{XML_CATALOG_FILES} environment variable is space-separated, it must
10368 contain a list of @file{catalog.xml} files (not directories), which are
10369 to be found in @file{xml} sub-directories---nothing less. The search
10370 path specification looks like this:
10375 ;; some fields omitted
10376 (native-search-paths
10377 (list (search-path-specification
10378 (variable "XML_CATALOG_FILES")
10381 (file-pattern "^catalog\\.xml$")
10382 (file-type 'regular)))))
10385 Worry not, search path specifications are usually not this tricky.
10387 The @code{(guix search-paths)} module defines the data type of search
10388 path specifications and a number of helper procedures. Below is the
10389 reference of search path specifications.
10391 @deftp {Data Type} search-path-specification
10392 The data type for search path specifications.
10395 @item @code{variable}
10396 The name of the environment variable for this search path (a string).
10399 The list of sub-directories (strings) that should be added to the search
10402 @item @code{separator} (default: @code{":"})
10403 The string used to separate search path components.
10405 As a special case, a @code{separator} value of @code{#f} specifies a
10406 ``single-component search path''---in other words, a search path that
10407 cannot contain more than one element. This is useful in some cases,
10408 such as the @code{SSL_CERT_DIR} variable (honored by OpenSSL, cURL, and
10409 a few other packages) or the @code{ASPELL_DICT_DIR} variable (honored by
10410 the GNU Aspell spell checker), both of which must point to a single
10413 @item @code{file-type} (default: @code{'directory})
10414 The type of file being matched---@code{'directory} or @code{'regular},
10415 though it can be any symbol returned by @code{stat:type} (@pxref{File
10416 System, @code{stat},, guile, GNU Guile Reference Manual}).
10418 In the libxml2 example above, we would match regular files; in the
10419 Python example, we would match directories.
10421 @item @code{file-pattern} (default: @code{#f})
10422 This must be either @code{#f} or a regular expression specifying
10423 files to be matched @emph{within} the sub-directories specified by the
10424 @code{files} field.
10426 Again, the libxml2 example shows a situation where this is needed.
10430 Some search paths are not tied by a single package but to many packages.
10431 To reduce duplications, some of them are pre-defined in @code{(guix
10434 @defvr {Scheme Variable} $SSL_CERT_DIR
10435 @defvrx {Scheme Variable} $SSL_CERT_FILE
10436 These two search paths indicate where X.509 certificates can be found
10437 (@pxref{X.509 Certificates}).
10440 These pre-defined search paths can be used as in the following example:
10445 ;; some fields omitted ...
10446 (native-search-paths (list $SSL_CERT_DIR $SSL_CERT_FILE)))
10449 How do you turn search path specifications on one hand and a bunch of
10450 directories on the other hand in a set of environment variable
10451 definitions? That's the job of @code{evaluate-search-paths}.
10453 @deffn {Scheme Procedure} evaluate-search-paths @var{search-paths} @
10454 @var{directories} [@var{getenv}]
10455 Evaluate @var{search-paths}, a list of search-path specifications, for
10456 @var{directories}, a list of directory names, and return a list of
10457 specification/value pairs. Use @var{getenv} to determine the current
10458 settings and report only settings not already effective.
10461 The @code{(guix profiles)} provides a higher-level helper procedure,
10462 @code{load-profile}, that sets the environment variables of a profile.
10468 @cindex store items
10469 @cindex store paths
10471 Conceptually, the @dfn{store} is the place where derivations that have
10472 been built successfully are stored---by default, @file{/gnu/store}.
10473 Sub-directories in the store are referred to as @dfn{store items} or
10474 sometimes @dfn{store paths}. The store has an associated database that
10475 contains information such as the store paths referred to by each store
10476 path, and the list of @emph{valid} store items---results of successful
10477 builds. This database resides in @file{@var{localstatedir}/guix/db},
10478 where @var{localstatedir} is the state directory specified @i{via}
10479 @option{--localstatedir} at configure time, usually @file{/var}.
10481 The store is @emph{always} accessed by the daemon on behalf of its clients
10482 (@pxref{Invoking guix-daemon}). To manipulate the store, clients
10483 connect to the daemon over a Unix-domain socket, send requests to it,
10484 and read the result---these are remote procedure calls, or RPCs.
10487 Users must @emph{never} modify files under @file{/gnu/store} directly.
10488 This would lead to inconsistencies and break the immutability
10489 assumptions of Guix's functional model (@pxref{Introduction}).
10491 @xref{Invoking guix gc, @command{guix gc --verify}}, for information on
10492 how to check the integrity of the store and attempt recovery from
10493 accidental modifications.
10496 The @code{(guix store)} module provides procedures to connect to the
10497 daemon, and to perform RPCs. These are described below. By default,
10498 @code{open-connection}, and thus all the @command{guix} commands,
10499 connect to the local daemon or to the URI specified by the
10500 @env{GUIX_DAEMON_SOCKET} environment variable.
10502 @defvr {Environment Variable} GUIX_DAEMON_SOCKET
10503 When set, the value of this variable should be a file name or a URI
10504 designating the daemon endpoint. When it is a file name, it denotes a
10505 Unix-domain socket to connect to. In addition to file names, the
10506 supported URI schemes are:
10511 These are for Unix-domain sockets.
10512 @code{file:///var/guix/daemon-socket/socket} is equivalent to
10513 @file{/var/guix/daemon-socket/socket}.
10516 @cindex daemon, remote access
10517 @cindex remote access to the daemon
10518 @cindex daemon, cluster setup
10519 @cindex clusters, daemon setup
10520 These URIs denote connections over TCP/IP, without encryption nor
10521 authentication of the remote host. The URI must specify the host name
10522 and optionally a port number (by default port 44146 is used):
10525 guix://master.guix.example.org:1234
10528 This setup is suitable on local networks, such as clusters, where only
10529 trusted nodes may connect to the build daemon at
10530 @code{master.guix.example.org}.
10532 The @option{--listen} option of @command{guix-daemon} can be used to
10533 instruct it to listen for TCP connections (@pxref{Invoking guix-daemon,
10534 @option{--listen}}).
10537 @cindex SSH access to build daemons
10538 These URIs allow you to connect to a remote daemon over SSH@. This
10539 feature requires Guile-SSH (@pxref{Requirements}) and a working
10540 @command{guile} binary in @env{PATH} on the destination machine. It
10541 supports public key and GSSAPI authentication. A typical URL might look
10545 ssh://charlie@@guix.example.org:22
10548 As for @command{guix copy}, the usual OpenSSH client configuration files
10549 are honored (@pxref{Invoking guix copy}).
10552 Additional URI schemes may be supported in the future.
10554 @c XXX: Remove this note when the protocol incurs fewer round trips
10555 @c and when (guix derivations) no longer relies on file system access.
10557 The ability to connect to remote build daemons is considered
10558 experimental as of @value{VERSION}. Please get in touch with us to
10559 share any problems or suggestions you may have (@pxref{Contributing}).
10563 @deffn {Scheme Procedure} open-connection [@var{uri}] [#:reserve-space? #t]
10564 Connect to the daemon over the Unix-domain socket at @var{uri} (a string). When
10565 @var{reserve-space?} is true, instruct it to reserve a little bit of
10566 extra space on the file system so that the garbage collector can still
10567 operate should the disk become full. Return a server object.
10569 @var{file} defaults to @code{%default-socket-path}, which is the normal
10570 location given the options that were passed to @command{configure}.
10573 @deffn {Scheme Procedure} close-connection @var{server}
10574 Close the connection to @var{server}.
10577 @defvr {Scheme Variable} current-build-output-port
10578 This variable is bound to a SRFI-39 parameter, which refers to the port
10579 where build and error logs sent by the daemon should be written.
10582 Procedures that make RPCs all take a server object as their first
10585 @deffn {Scheme Procedure} valid-path? @var{server} @var{path}
10586 @cindex invalid store items
10587 Return @code{#t} when @var{path} designates a valid store item and
10588 @code{#f} otherwise (an invalid item may exist on disk but still be
10589 invalid, for instance because it is the result of an aborted or failed
10592 A @code{&store-protocol-error} condition is raised if @var{path} is not
10593 prefixed by the store directory (@file{/gnu/store}).
10596 @deffn {Scheme Procedure} add-text-to-store @var{server} @var{name} @var{text} [@var{references}]
10597 Add @var{text} under file @var{name} in the store, and return its store
10598 path. @var{references} is the list of store paths referred to by the
10599 resulting store path.
10602 @deffn {Scheme Procedure} build-derivations @var{store} @var{derivations} @
10604 Build @var{derivations}, a list of @code{<derivation>} objects, @file{.drv}
10605 file names, or derivation/output pairs, using the specified
10606 @var{mode}---@code{(build-mode normal)} by default.
10609 Note that the @code{(guix monads)} module provides a monad as well as
10610 monadic versions of the above procedures, with the goal of making it
10611 more convenient to work with code that accesses the store (@pxref{The
10615 @i{This section is currently incomplete.}
10618 @section Derivations
10620 @cindex derivations
10621 Low-level build actions and the environment in which they are performed
10622 are represented by @dfn{derivations}. A derivation contains the
10623 following pieces of information:
10627 The outputs of the derivation---derivations produce at least one file or
10628 directory in the store, but may produce more.
10631 @cindex build-time dependencies
10632 @cindex dependencies, build-time
10633 The inputs of the derivations---i.e., its build-time dependencies---which may
10634 be other derivations or plain files in the store (patches, build scripts,
10638 The system type targeted by the derivation---e.g., @code{x86_64-linux}.
10641 The file name of a build script in the store, along with the arguments
10645 A list of environment variables to be defined.
10649 @cindex derivation path
10650 Derivations allow clients of the daemon to communicate build actions to
10651 the store. They exist in two forms: as an in-memory representation,
10652 both on the client- and daemon-side, and as files in the store whose
10653 name end in @file{.drv}---these files are referred to as @dfn{derivation
10654 paths}. Derivations paths can be passed to the @code{build-derivations}
10655 procedure to perform the build actions they prescribe (@pxref{The
10658 @cindex fixed-output derivations
10659 Operations such as file downloads and version-control checkouts for
10660 which the expected content hash is known in advance are modeled as
10661 @dfn{fixed-output derivations}. Unlike regular derivations, the outputs
10662 of a fixed-output derivation are independent of its inputs---e.g., a
10663 source code download produces the same result regardless of the download
10664 method and tools being used.
10667 @cindex run-time dependencies
10668 @cindex dependencies, run-time
10669 The outputs of derivations---i.e., the build results---have a set of
10670 @dfn{references}, as reported by the @code{references} RPC or the
10671 @command{guix gc --references} command (@pxref{Invoking guix gc}). References
10672 are the set of run-time dependencies of the build results. References are a
10673 subset of the inputs of the derivation; this subset is automatically computed
10674 by the build daemon by scanning all the files in the outputs.
10676 The @code{(guix derivations)} module provides a representation of
10677 derivations as Scheme objects, along with procedures to create and
10678 otherwise manipulate derivations. The lowest-level primitive to create
10679 a derivation is the @code{derivation} procedure:
10681 @deffn {Scheme Procedure} derivation @var{store} @var{name} @var{builder} @
10682 @var{args} [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
10683 [#:recursive? #f] [#:inputs '()] [#:env-vars '()] @
10684 [#:system (%current-system)] [#:references-graphs #f] @
10685 [#:allowed-references #f] [#:disallowed-references #f] @
10686 [#:leaked-env-vars #f] [#:local-build? #f] @
10687 [#:substitutable? #t] [#:properties '()]
10688 Build a derivation with the given arguments, and return the resulting
10689 @code{<derivation>} object.
10691 When @var{hash} and @var{hash-algo} are given, a
10692 @dfn{fixed-output derivation} is created---i.e., one whose result is
10693 known in advance, such as a file download. If, in addition,
10694 @var{recursive?} is true, then that fixed output may be an executable
10695 file or a directory and @var{hash} must be the hash of an archive
10696 containing this output.
10698 When @var{references-graphs} is true, it must be a list of file
10699 name/store path pairs. In that case, the reference graph of each store
10700 path is exported in the build environment in the corresponding file, in
10701 a simple text format.
10703 When @var{allowed-references} is true, it must be a list of store items
10704 or outputs that the derivation's output may refer to. Likewise,
10705 @var{disallowed-references}, if true, must be a list of things the
10706 outputs may @emph{not} refer to.
10708 When @var{leaked-env-vars} is true, it must be a list of strings
10709 denoting environment variables that are allowed to ``leak'' from the
10710 daemon's environment to the build environment. This is only applicable
10711 to fixed-output derivations---i.e., when @var{hash} is true. The main
10712 use is to allow variables such as @code{http_proxy} to be passed to
10713 derivations that download files.
10715 When @var{local-build?} is true, declare that the derivation is not a
10716 good candidate for offloading and should rather be built locally
10717 (@pxref{Daemon Offload Setup}). This is the case for small derivations
10718 where the costs of data transfers would outweigh the benefits.
10720 When @var{substitutable?} is false, declare that substitutes of the
10721 derivation's output should not be used (@pxref{Substitutes}). This is
10722 useful, for instance, when building packages that capture details of the
10723 host CPU instruction set.
10725 @var{properties} must be an association list describing ``properties'' of the
10726 derivation. It is kept as-is, uninterpreted, in the derivation.
10730 Here's an example with a shell script as its builder, assuming
10731 @var{store} is an open connection to the daemon, and @var{bash} points
10732 to a Bash executable in the store:
10735 (use-modules (guix utils)
10737 (guix derivations))
10739 (let ((builder ; add the Bash script to the store
10740 (add-text-to-store store "my-builder.sh"
10741 "echo hello world > $out\n" '())))
10742 (derivation store "foo"
10743 bash `("-e" ,builder)
10744 #:inputs `((,bash) (,builder))
10745 #:env-vars '(("HOME" . "/homeless"))))
10746 @result{} #<derivation /gnu/store/@dots{}-foo.drv => /gnu/store/@dots{}-foo>
10749 As can be guessed, this primitive is cumbersome to use directly. A
10750 better approach is to write build scripts in Scheme, of course! The
10751 best course of action for that is to write the build code as a
10752 ``G-expression'', and to pass it to @code{gexp->derivation}. For more
10753 information, @pxref{G-Expressions}.
10755 Once upon a time, @code{gexp->derivation} did not exist and constructing
10756 derivations with build code written in Scheme was achieved with
10757 @code{build-expression->derivation}, documented below. This procedure
10758 is now deprecated in favor of the much nicer @code{gexp->derivation}.
10760 @deffn {Scheme Procedure} build-expression->derivation @var{store} @
10761 @var{name} @var{exp} @
10762 [#:system (%current-system)] [#:inputs '()] @
10763 [#:outputs '("out")] [#:hash #f] [#:hash-algo #f] @
10764 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
10765 [#:references-graphs #f] [#:allowed-references #f] @
10766 [#:disallowed-references #f] @
10767 [#:local-build? #f] [#:substitutable? #t] [#:guile-for-build #f]
10768 Return a derivation that executes Scheme expression @var{exp} as a
10769 builder for derivation @var{name}. @var{inputs} must be a list of
10770 @code{(name drv-path sub-drv)} tuples; when @var{sub-drv} is omitted,
10771 @code{"out"} is assumed. @var{modules} is a list of names of Guile
10772 modules from the current search path to be copied in the store,
10773 compiled, and made available in the load path during the execution of
10774 @var{exp}---e.g., @code{((guix build utils) (guix build
10775 gnu-build-system))}.
10777 @var{exp} is evaluated in an environment where @code{%outputs} is bound
10778 to a list of output/path pairs, and where @code{%build-inputs} is bound
10779 to a list of string/output-path pairs made from @var{inputs}.
10780 Optionally, @var{env-vars} is a list of string pairs specifying the name
10781 and value of environment variables visible to the builder. The builder
10782 terminates by passing the result of @var{exp} to @code{exit}; thus, when
10783 @var{exp} returns @code{#f}, the build is considered to have failed.
10785 @var{exp} is built using @var{guile-for-build} (a derivation). When
10786 @var{guile-for-build} is omitted or is @code{#f}, the value of the
10787 @code{%guile-for-build} fluid is used instead.
10789 See the @code{derivation} procedure for the meaning of
10790 @var{references-graphs}, @var{allowed-references},
10791 @var{disallowed-references}, @var{local-build?}, and
10792 @var{substitutable?}.
10796 Here's an example of a single-output derivation that creates a directory
10797 containing one file:
10800 (let ((builder '(let ((out (assoc-ref %outputs "out")))
10801 (mkdir out) ; create /gnu/store/@dots{}-goo
10802 (call-with-output-file (string-append out "/test")
10804 (display '(hello guix) p))))))
10805 (build-expression->derivation store "goo" builder))
10807 @result{} #<derivation /gnu/store/@dots{}-goo.drv => @dots{}>
10811 @node The Store Monad
10812 @section The Store Monad
10816 The procedures that operate on the store described in the previous
10817 sections all take an open connection to the build daemon as their first
10818 argument. Although the underlying model is functional, they either have
10819 side effects or depend on the current state of the store.
10821 The former is inconvenient: the connection to the build daemon has to be
10822 carried around in all those functions, making it impossible to compose
10823 functions that do not take that parameter with functions that do. The
10824 latter can be problematic: since store operations have side effects
10825 and/or depend on external state, they have to be properly sequenced.
10827 @cindex monadic values
10828 @cindex monadic functions
10829 This is where the @code{(guix monads)} module comes in. This module
10830 provides a framework for working with @dfn{monads}, and a particularly
10831 useful monad for our uses, the @dfn{store monad}. Monads are a
10832 construct that allows two things: associating ``context'' with values
10833 (in our case, the context is the store), and building sequences of
10834 computations (here computations include accesses to the store). Values
10835 in a monad---values that carry this additional context---are called
10836 @dfn{monadic values}; procedures that return such values are called
10837 @dfn{monadic procedures}.
10839 Consider this ``normal'' procedure:
10842 (define (sh-symlink store)
10843 ;; Return a derivation that symlinks the 'bash' executable.
10844 (let* ((drv (package-derivation store bash))
10845 (out (derivation->output-path drv))
10846 (sh (string-append out "/bin/bash")))
10847 (build-expression->derivation store "sh"
10848 `(symlink ,sh %output))))
10851 Using @code{(guix monads)} and @code{(guix gexp)}, it may be rewritten
10852 as a monadic function:
10855 (define (sh-symlink)
10856 ;; Same, but return a monadic value.
10857 (mlet %store-monad ((drv (package->derivation bash)))
10858 (gexp->derivation "sh"
10859 #~(symlink (string-append #$drv "/bin/bash")
10863 There are several things to note in the second version: the @code{store}
10864 parameter is now implicit and is ``threaded'' in the calls to the
10865 @code{package->derivation} and @code{gexp->derivation} monadic
10866 procedures, and the monadic value returned by @code{package->derivation}
10867 is @dfn{bound} using @code{mlet} instead of plain @code{let}.
10869 As it turns out, the call to @code{package->derivation} can even be
10870 omitted since it will take place implicitly, as we will see later
10871 (@pxref{G-Expressions}):
10874 (define (sh-symlink)
10875 (gexp->derivation "sh"
10876 #~(symlink (string-append #$bash "/bin/bash")
10881 @c <https://syntaxexclamation.wordpress.com/2014/06/26/escaping-continuations/>
10882 @c for the funny quote.
10883 Calling the monadic @code{sh-symlink} has no effect. As someone once
10884 said, ``you exit a monad like you exit a building on fire: by running''.
10885 So, to exit the monad and get the desired effect, one must use
10886 @code{run-with-store}:
10889 (run-with-store (open-connection) (sh-symlink))
10890 @result{} /gnu/store/...-sh-symlink
10893 Note that the @code{(guix monad-repl)} module extends the Guile REPL with
10894 new ``commands'' to make it easier to deal with monadic procedures:
10895 @code{run-in-store}, and @code{enter-store-monad} (@pxref{Using Guix
10896 Interactively}). The former is used
10897 to ``run'' a single monadic value through the store:
10900 scheme@@(guile-user)> ,run-in-store (package->derivation hello)
10901 $1 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
10904 The latter enters a recursive REPL, where all the return values are
10905 automatically run through the store:
10908 scheme@@(guile-user)> ,enter-store-monad
10909 store-monad@@(guile-user) [1]> (package->derivation hello)
10910 $2 = #<derivation /gnu/store/@dots{}-hello-2.9.drv => @dots{}>
10911 store-monad@@(guile-user) [1]> (text-file "foo" "Hello!")
10912 $3 = "/gnu/store/@dots{}-foo"
10913 store-monad@@(guile-user) [1]> ,q
10914 scheme@@(guile-user)>
10918 Note that non-monadic values cannot be returned in the
10919 @code{store-monad} REPL.
10921 Other meta-commands are available at the REPL, such as @code{,build} to
10922 build a file-like object (@pxref{Using Guix Interactively}).
10924 The main syntactic forms to deal with monads in general are provided by
10925 the @code{(guix monads)} module and are described below.
10927 @deffn {Scheme Syntax} with-monad @var{monad} @var{body} ...
10928 Evaluate any @code{>>=} or @code{return} forms in @var{body} as being
10932 @deffn {Scheme Syntax} return @var{val}
10933 Return a monadic value that encapsulates @var{val}.
10936 @deffn {Scheme Syntax} >>= @var{mval} @var{mproc} ...
10937 @dfn{Bind} monadic value @var{mval}, passing its ``contents'' to monadic
10938 procedures @var{mproc}@dots{}@footnote{This operation is commonly
10939 referred to as ``bind'', but that name denotes an unrelated procedure in
10940 Guile. Thus we use this somewhat cryptic symbol inherited from the
10941 Haskell language.}. There can be one @var{mproc} or several of them, as
10946 (with-monad %state-monad
10948 (lambda (x) (return (+ 1 x)))
10949 (lambda (x) (return (* 2 x)))))
10953 @result{} some-state
10957 @deffn {Scheme Syntax} mlet @var{monad} ((@var{var} @var{mval}) ...) @
10959 @deffnx {Scheme Syntax} mlet* @var{monad} ((@var{var} @var{mval}) ...) @
10961 Bind the variables @var{var} to the monadic values @var{mval} in
10962 @var{body}, which is a sequence of expressions. As with the bind
10963 operator, this can be thought of as ``unpacking'' the raw, non-monadic
10964 value ``contained'' in @var{mval} and making @var{var} refer to that
10965 raw, non-monadic value within the scope of the @var{body}. The form
10966 (@var{var} -> @var{val}) binds @var{var} to the ``normal'' value
10967 @var{val}, as per @code{let}. The binding operations occur in sequence
10968 from left to right. The last expression of @var{body} must be a monadic
10969 expression, and its result will become the result of the @code{mlet} or
10970 @code{mlet*} when run in the @var{monad}.
10972 @code{mlet*} is to @code{mlet} what @code{let*} is to @code{let}
10973 (@pxref{Local Bindings,,, guile, GNU Guile Reference Manual}).
10976 @deffn {Scheme System} mbegin @var{monad} @var{mexp} ...
10977 Bind @var{mexp} and the following monadic expressions in sequence,
10978 returning the result of the last expression. Every expression in the
10979 sequence must be a monadic expression.
10981 This is akin to @code{mlet}, except that the return values of the
10982 monadic expressions are ignored. In that sense, it is analogous to
10983 @code{begin}, but applied to monadic expressions.
10986 @deffn {Scheme System} mwhen @var{condition} @var{mexp0} @var{mexp*} ...
10987 When @var{condition} is true, evaluate the sequence of monadic
10988 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
10989 @var{condition} is false, return @code{*unspecified*} in the current
10990 monad. Every expression in the sequence must be a monadic expression.
10993 @deffn {Scheme System} munless @var{condition} @var{mexp0} @var{mexp*} ...
10994 When @var{condition} is false, evaluate the sequence of monadic
10995 expressions @var{mexp0}..@var{mexp*} as in an @code{mbegin}. When
10996 @var{condition} is true, return @code{*unspecified*} in the current
10997 monad. Every expression in the sequence must be a monadic expression.
11000 @cindex state monad
11001 The @code{(guix monads)} module provides the @dfn{state monad}, which
11002 allows an additional value---the state---to be @emph{threaded} through
11003 monadic procedure calls.
11005 @defvr {Scheme Variable} %state-monad
11006 The state monad. Procedures in the state monad can access and change
11007 the state that is threaded.
11009 Consider the example below. The @code{square} procedure returns a value
11010 in the state monad. It returns the square of its argument, but also
11011 increments the current state value:
11015 (mlet %state-monad ((count (current-state)))
11016 (mbegin %state-monad
11017 (set-current-state (+ 1 count))
11018 (return (* x x)))))
11020 (run-with-state (sequence %state-monad (map square (iota 3))) 0)
11025 When ``run'' through @code{%state-monad}, we obtain that additional state
11026 value, which is the number of @code{square} calls.
11029 @deffn {Monadic Procedure} current-state
11030 Return the current state as a monadic value.
11033 @deffn {Monadic Procedure} set-current-state @var{value}
11034 Set the current state to @var{value} and return the previous state as a
11038 @deffn {Monadic Procedure} state-push @var{value}
11039 Push @var{value} to the current state, which is assumed to be a list,
11040 and return the previous state as a monadic value.
11043 @deffn {Monadic Procedure} state-pop
11044 Pop a value from the current state and return it as a monadic value.
11045 The state is assumed to be a list.
11048 @deffn {Scheme Procedure} run-with-state @var{mval} [@var{state}]
11049 Run monadic value @var{mval} starting with @var{state} as the initial
11050 state. Return two values: the resulting value, and the resulting state.
11053 The main interface to the store monad, provided by the @code{(guix
11054 store)} module, is as follows.
11056 @defvr {Scheme Variable} %store-monad
11057 The store monad---an alias for @code{%state-monad}.
11059 Values in the store monad encapsulate accesses to the store. When its
11060 effect is needed, a value of the store monad must be ``evaluated'' by
11061 passing it to the @code{run-with-store} procedure (see below).
11064 @deffn {Scheme Procedure} run-with-store @var{store} @var{mval} [#:guile-for-build] [#:system (%current-system)]
11065 Run @var{mval}, a monadic value in the store monad, in @var{store}, an
11066 open store connection.
11069 @deffn {Monadic Procedure} text-file @var{name} @var{text} [@var{references}]
11070 Return as a monadic value the absolute file name in the store of the file
11071 containing @var{text}, a string. @var{references} is a list of store items that the
11072 resulting text file refers to; it defaults to the empty list.
11075 @deffn {Monadic Procedure} binary-file @var{name} @var{data} [@var{references}]
11076 Return as a monadic value the absolute file name in the store of the file
11077 containing @var{data}, a bytevector. @var{references} is a list of store
11078 items that the resulting binary file refers to; it defaults to the empty list.
11081 @deffn {Monadic Procedure} interned-file @var{file} [@var{name}] @
11082 [#:recursive? #t] [#:select? (const #t)]
11083 Return the name of @var{file} once interned in the store. Use
11084 @var{name} as its store name, or the basename of @var{file} if
11085 @var{name} is omitted.
11087 When @var{recursive?} is true, the contents of @var{file} are added
11088 recursively; if @var{file} designates a flat file and @var{recursive?}
11089 is true, its contents are added, and its permission bits are kept.
11091 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
11092 @var{stat})} for each directory entry, where @var{file} is the entry's
11093 absolute file name and @var{stat} is the result of @code{lstat}; exclude
11094 entries for which @var{select?} does not return true.
11096 The example below adds a file to the store, under two different names:
11099 (run-with-store (open-connection)
11100 (mlet %store-monad ((a (interned-file "README"))
11101 (b (interned-file "README" "LEGU-MIN")))
11102 (return (list a b))))
11104 @result{} ("/gnu/store/rwm@dots{}-README" "/gnu/store/44i@dots{}-LEGU-MIN")
11109 The @code{(guix packages)} module exports the following package-related
11110 monadic procedures:
11112 @deffn {Monadic Procedure} package-file @var{package} [@var{file}] @
11113 [#:system (%current-system)] [#:target #f] @
11115 Return as a monadic
11116 value in the absolute file name of @var{file} within the @var{output}
11117 directory of @var{package}. When @var{file} is omitted, return the name
11118 of the @var{output} directory of @var{package}. When @var{target} is
11119 true, use it as a cross-compilation target triplet.
11121 Note that this procedure does @emph{not} build @var{package}. Thus, the
11122 result might or might not designate an existing file. We recommend not
11123 using this procedure unless you know what you are doing.
11126 @deffn {Monadic Procedure} package->derivation @var{package} [@var{system}]
11127 @deffnx {Monadic Procedure} package->cross-derivation @var{package} @
11128 @var{target} [@var{system}]
11129 Monadic version of @code{package-derivation} and
11130 @code{package-cross-derivation} (@pxref{Defining Packages}).
11134 @node G-Expressions
11135 @section G-Expressions
11137 @cindex G-expression
11138 @cindex build code quoting
11139 So we have ``derivations'', which represent a sequence of build actions
11140 to be performed to produce an item in the store (@pxref{Derivations}).
11141 These build actions are performed when asking the daemon to actually
11142 build the derivations; they are run by the daemon in a container
11143 (@pxref{Invoking guix-daemon}).
11145 @cindex code staging
11146 @cindex staging, of code
11147 @cindex strata of code
11148 It should come as no surprise that we like to write these build actions
11149 in Scheme. When we do that, we end up with two @dfn{strata} of Scheme
11150 code@footnote{The term @dfn{stratum} in this context was coined by
11151 Manuel Serrano et al.@: in the context of their work on Hop. Oleg
11152 Kiselyov, who has written insightful
11153 @url{http://okmij.org/ftp/meta-programming/#meta-scheme, essays and code
11154 on this topic}, refers to this kind of code generation as
11155 @dfn{staging}.}: the ``host code''---code that defines packages, talks
11156 to the daemon, etc.---and the ``build code''---code that actually
11157 performs build actions, such as making directories, invoking
11158 @command{make}, and so on (@pxref{Build Phases}).
11160 To describe a derivation and its build actions, one typically needs to
11161 embed build code inside host code. It boils down to manipulating build
11162 code as data, and the homoiconicity of Scheme---code has a direct
11163 representation as data---comes in handy for that. But we need more than
11164 the normal @code{quasiquote} mechanism in Scheme to construct build
11167 The @code{(guix gexp)} module implements @dfn{G-expressions}, a form of
11168 S-expressions adapted to build expressions. G-expressions, or
11169 @dfn{gexps}, consist essentially of three syntactic forms: @code{gexp},
11170 @code{ungexp}, and @code{ungexp-splicing} (or simply: @code{#~},
11171 @code{#$}, and @code{#$@@}), which are comparable to
11172 @code{quasiquote}, @code{unquote}, and @code{unquote-splicing},
11173 respectively (@pxref{Expression Syntax, @code{quasiquote},, guile,
11174 GNU Guile Reference Manual}). However, there are major differences:
11178 Gexps are meant to be written to a file and run or manipulated by other
11182 When a high-level object such as a package or derivation is unquoted
11183 inside a gexp, the result is as if its output file name had been
11187 Gexps carry information about the packages or derivations they refer to,
11188 and these dependencies are automatically added as inputs to the build
11189 processes that use them.
11192 @cindex lowering, of high-level objects in gexps
11193 This mechanism is not limited to package and derivation
11194 objects: @dfn{compilers} able to ``lower'' other high-level objects to
11195 derivations or files in the store can be defined,
11196 such that these objects can also be inserted
11197 into gexps. For example, a useful type of high-level objects that can be
11198 inserted in a gexp is ``file-like objects'', which make it easy to
11199 add files to the store and to refer to them in
11200 derivations and such (see @code{local-file} and @code{plain-file}
11203 To illustrate the idea, here is an example of a gexp:
11210 (symlink (string-append #$coreutils "/bin/ls")
11214 This gexp can be passed to @code{gexp->derivation}; we obtain a
11215 derivation that builds a directory containing exactly one symlink to
11216 @file{/gnu/store/@dots{}-coreutils-8.22/bin/ls}:
11219 (gexp->derivation "the-thing" build-exp)
11222 As one would expect, the @code{"/gnu/store/@dots{}-coreutils-8.22"} string is
11223 substituted to the reference to the @var{coreutils} package in the
11224 actual build code, and @var{coreutils} is automatically made an input to
11225 the derivation. Likewise, @code{#$output} (equivalent to @code{(ungexp
11226 output)}) is replaced by a string containing the directory name of the
11227 output of the derivation.
11229 @cindex cross compilation
11230 In a cross-compilation context, it is useful to distinguish between
11231 references to the @emph{native} build of a package---that can run on the
11232 host---versus references to cross builds of a package. To that end, the
11233 @code{#+} plays the same role as @code{#$}, but is a reference to a
11234 native package build:
11237 (gexp->derivation "vi"
11240 (mkdir (string-append #$output "/bin"))
11241 (system* (string-append #+coreutils "/bin/ln")
11243 (string-append #$emacs "/bin/emacs")
11244 (string-append #$output "/bin/vi")))
11245 #:target "aarch64-linux-gnu")
11249 In the example above, the native build of @var{coreutils} is used, so
11250 that @command{ln} can actually run on the host; but then the
11251 cross-compiled build of @var{emacs} is referenced.
11253 @cindex imported modules, for gexps
11254 @findex with-imported-modules
11255 Another gexp feature is @dfn{imported modules}: sometimes you want to be
11256 able to use certain Guile modules from the ``host environment'' in the
11257 gexp, so those modules should be imported in the ``build environment''.
11258 The @code{with-imported-modules} form allows you to express that:
11261 (let ((build (with-imported-modules '((guix build utils))
11263 (use-modules (guix build utils))
11264 (mkdir-p (string-append #$output "/bin"))))))
11265 (gexp->derivation "empty-dir"
11268 (display "success!\n")
11273 In this example, the @code{(guix build utils)} module is automatically
11274 pulled into the isolated build environment of our gexp, such that
11275 @code{(use-modules (guix build utils))} works as expected.
11277 @cindex module closure
11278 @findex source-module-closure
11279 Usually you want the @emph{closure} of the module to be imported---i.e.,
11280 the module itself and all the modules it depends on---rather than just
11281 the module; failing to do that, attempts to use the module will fail
11282 because of missing dependent modules. The @code{source-module-closure}
11283 procedure computes the closure of a module by looking at its source file
11284 headers, which comes in handy in this case:
11287 (use-modules (guix modules)) ;for 'source-module-closure'
11289 (with-imported-modules (source-module-closure
11290 '((guix build utils)
11291 (gnu build image)))
11292 (gexp->derivation "something-with-vms"
11294 (use-modules (guix build utils)
11299 @cindex extensions, for gexps
11300 @findex with-extensions
11301 In the same vein, sometimes you want to import not just pure-Scheme
11302 modules, but also ``extensions'' such as Guile bindings to C libraries
11303 or other ``full-blown'' packages. Say you need the @code{guile-json}
11304 package available on the build side, here's how you would do it:
11307 (use-modules (gnu packages guile)) ;for 'guile-json'
11309 (with-extensions (list guile-json)
11310 (gexp->derivation "something-with-json"
11312 (use-modules (json))
11316 The syntactic form to construct gexps is summarized below.
11318 @deffn {Scheme Syntax} #~@var{exp}
11319 @deffnx {Scheme Syntax} (gexp @var{exp})
11320 Return a G-expression containing @var{exp}. @var{exp} may contain one
11321 or more of the following forms:
11325 @itemx (ungexp @var{obj})
11326 Introduce a reference to @var{obj}. @var{obj} may have one of the
11327 supported types, for example a package or a
11328 derivation, in which case the @code{ungexp} form is replaced by its
11329 output file name---e.g., @code{"/gnu/store/@dots{}-coreutils-8.22}.
11331 If @var{obj} is a list, it is traversed and references to supported
11332 objects are substituted similarly.
11334 If @var{obj} is another gexp, its contents are inserted and its
11335 dependencies are added to those of the containing gexp.
11337 If @var{obj} is another kind of object, it is inserted as is.
11339 @item #$@var{obj}:@var{output}
11340 @itemx (ungexp @var{obj} @var{output})
11341 This is like the form above, but referring explicitly to the
11342 @var{output} of @var{obj}---this is useful when @var{obj} produces
11343 multiple outputs (@pxref{Packages with Multiple Outputs}).
11346 @itemx #+@var{obj}:output
11347 @itemx (ungexp-native @var{obj})
11348 @itemx (ungexp-native @var{obj} @var{output})
11349 Same as @code{ungexp}, but produces a reference to the @emph{native}
11350 build of @var{obj} when used in a cross compilation context.
11352 @item #$output[:@var{output}]
11353 @itemx (ungexp output [@var{output}])
11354 Insert a reference to derivation output @var{output}, or to the main
11355 output when @var{output} is omitted.
11357 This only makes sense for gexps passed to @code{gexp->derivation}.
11359 @item #$@@@var{lst}
11360 @itemx (ungexp-splicing @var{lst})
11361 Like the above, but splices the contents of @var{lst} inside the
11364 @item #+@@@var{lst}
11365 @itemx (ungexp-native-splicing @var{lst})
11366 Like the above, but refers to native builds of the objects listed in
11371 G-expressions created by @code{gexp} or @code{#~} are run-time objects
11372 of the @code{gexp?} type (see below).
11375 @deffn {Scheme Syntax} with-imported-modules @var{modules} @var{body}@dots{}
11376 Mark the gexps defined in @var{body}@dots{} as requiring @var{modules}
11377 in their execution environment.
11379 Each item in @var{modules} can be the name of a module, such as
11380 @code{(guix build utils)}, or it can be a module name, followed by an
11381 arrow, followed by a file-like object:
11384 `((guix build utils)
11386 ((guix config) => ,(scheme-file "config.scm"
11387 #~(define-module @dots{}))))
11391 In the example above, the first two modules are taken from the search
11392 path, and the last one is created from the given file-like object.
11394 This form has @emph{lexical} scope: it has an effect on the gexps
11395 directly defined in @var{body}@dots{}, but not on those defined, say, in
11396 procedures called from @var{body}@dots{}.
11399 @deffn {Scheme Syntax} with-extensions @var{extensions} @var{body}@dots{}
11400 Mark the gexps defined in @var{body}@dots{} as requiring
11401 @var{extensions} in their build and execution environment.
11402 @var{extensions} is typically a list of package objects such as those
11403 defined in the @code{(gnu packages guile)} module.
11405 Concretely, the packages listed in @var{extensions} are added to the
11406 load path while compiling imported modules in @var{body}@dots{}; they
11407 are also added to the load path of the gexp returned by
11411 @deffn {Scheme Procedure} gexp? @var{obj}
11412 Return @code{#t} if @var{obj} is a G-expression.
11415 G-expressions are meant to be written to disk, either as code building
11416 some derivation, or as plain files in the store. The monadic procedures
11417 below allow you to do that (@pxref{The Store Monad}, for more
11418 information about monads).
11420 @deffn {Monadic Procedure} gexp->derivation @var{name} @var{exp} @
11421 [#:system (%current-system)] [#:target #f] [#:graft? #t] @
11422 [#:hash #f] [#:hash-algo #f] @
11423 [#:recursive? #f] [#:env-vars '()] [#:modules '()] @
11424 [#:module-path @code{%load-path}] @
11425 [#:effective-version "2.2"] @
11426 [#:references-graphs #f] [#:allowed-references #f] @
11427 [#:disallowed-references #f] @
11428 [#:leaked-env-vars #f] @
11429 [#:script-name (string-append @var{name} "-builder")] @
11430 [#:deprecation-warnings #f] @
11431 [#:local-build? #f] [#:substitutable? #t] @
11432 [#:properties '()] [#:guile-for-build #f]
11433 Return a derivation @var{name} that runs @var{exp} (a gexp) with
11434 @var{guile-for-build} (a derivation) on @var{system}; @var{exp} is
11435 stored in a file called @var{script-name}. When @var{target} is true,
11436 it is used as the cross-compilation target triplet for packages referred
11439 @var{modules} is deprecated in favor of @code{with-imported-modules}.
11441 make @var{modules} available in the evaluation context of @var{exp};
11442 @var{modules} is a list of names of Guile modules searched in
11443 @var{module-path} to be copied in the store, compiled, and made available in
11444 the load path during the execution of @var{exp}---e.g., @code{((guix
11445 build utils) (guix build gnu-build-system))}.
11447 @var{effective-version} determines the string to use when adding extensions of
11448 @var{exp} (see @code{with-extensions}) to the search path---e.g., @code{"2.2"}.
11450 @var{graft?} determines whether packages referred to by @var{exp} should be grafted when
11453 When @var{references-graphs} is true, it must be a list of tuples of one of the
11457 (@var{file-name} @var{package})
11458 (@var{file-name} @var{package} @var{output})
11459 (@var{file-name} @var{derivation})
11460 (@var{file-name} @var{derivation} @var{output})
11461 (@var{file-name} @var{store-item})
11464 The right-hand-side of each element of @var{references-graphs} is automatically made
11465 an input of the build process of @var{exp}. In the build environment, each
11466 @var{file-name} contains the reference graph of the corresponding item, in a simple
11469 @var{allowed-references} must be either @code{#f} or a list of output names and packages.
11470 In the latter case, the list denotes store items that the result is allowed to
11471 refer to. Any reference to another store item will lead to a build error.
11472 Similarly for @var{disallowed-references}, which can list items that must not be
11473 referenced by the outputs.
11475 @var{deprecation-warnings} determines whether to show deprecation warnings while
11476 compiling modules. It can be @code{#f}, @code{#t}, or @code{'detailed}.
11478 The other arguments are as for @code{derivation} (@pxref{Derivations}).
11481 @cindex file-like objects
11482 The @code{local-file}, @code{plain-file}, @code{computed-file},
11483 @code{program-file}, and @code{scheme-file} procedures below return
11484 @dfn{file-like objects}. That is, when unquoted in a G-expression,
11485 these objects lead to a file in the store. Consider this G-expression:
11488 #~(system* #$(file-append glibc "/sbin/nscd") "-f"
11489 #$(local-file "/tmp/my-nscd.conf"))
11492 The effect here is to ``intern'' @file{/tmp/my-nscd.conf} by copying it
11493 to the store. Once expanded, for instance @i{via}
11494 @code{gexp->derivation}, the G-expression refers to that copy under
11495 @file{/gnu/store}; thus, modifying or removing the file in @file{/tmp}
11496 does not have any effect on what the G-expression does.
11497 @code{plain-file} can be used similarly; it differs in that the file
11498 content is directly passed as a string.
11500 @deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
11501 [#:recursive? #f] [#:select? (const #t)]
11502 Return an object representing local file @var{file} to add to the store;
11503 this object can be used in a gexp. If @var{file} is a literal string
11504 denoting a relative file name, it is looked up relative to the source
11505 file where it appears; if @var{file} is not a literal string, it is
11506 looked up relative to the current working directory at run time.
11507 @var{file} will be added to the store under @var{name}--by default the
11508 base name of @var{file}.
11510 When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
11511 designates a flat file and @var{recursive?} is true, its contents are added, and its
11512 permission bits are kept.
11514 When @var{recursive?} is true, call @code{(@var{select?} @var{file}
11515 @var{stat})} for each directory entry, where @var{file} is the entry's
11516 absolute file name and @var{stat} is the result of @code{lstat}; exclude
11517 entries for which @var{select?} does not return true.
11519 This is the declarative counterpart of the @code{interned-file} monadic
11520 procedure (@pxref{The Store Monad, @code{interned-file}}).
11523 @deffn {Scheme Procedure} plain-file @var{name} @var{content}
11524 Return an object representing a text file called @var{name} with the given
11525 @var{content} (a string or a bytevector) to be added to the store.
11527 This is the declarative counterpart of @code{text-file}.
11530 @deffn {Scheme Procedure} computed-file @var{name} @var{gexp} @
11531 [#:local-build? #t]
11533 Return an object representing the store item @var{name}, a file or
11534 directory computed by @var{gexp}. When @var{local-build?} is true (the
11535 default), the derivation is built locally. @var{options} is a list of
11536 additional arguments to pass to @code{gexp->derivation}.
11538 This is the declarative counterpart of @code{gexp->derivation}.
11541 @deffn {Monadic Procedure} gexp->script @var{name} @var{exp} @
11542 [#:guile (default-guile)] [#:module-path %load-path] @
11543 [#:system (%current-system)] [#:target #f]
11544 Return an executable script @var{name} that runs @var{exp} using
11545 @var{guile}, with @var{exp}'s imported modules in its search path.
11546 Look up @var{exp}'s modules in @var{module-path}.
11548 The example below builds a script that simply invokes the @command{ls}
11552 (use-modules (guix gexp) (gnu packages base))
11554 (gexp->script "list-files"
11555 #~(execl #$(file-append coreutils "/bin/ls")
11559 When ``running'' it through the store (@pxref{The Store Monad,
11560 @code{run-with-store}}), we obtain a derivation that produces an
11561 executable file @file{/gnu/store/@dots{}-list-files} along these lines:
11564 #!/gnu/store/@dots{}-guile-2.0.11/bin/guile -ds
11566 (execl "/gnu/store/@dots{}-coreutils-8.22"/bin/ls" "ls")
11570 @deffn {Scheme Procedure} program-file @var{name} @var{exp} @
11571 [#:guile #f] [#:module-path %load-path]
11572 Return an object representing the executable store item @var{name} that
11573 runs @var{gexp}. @var{guile} is the Guile package used to execute that
11574 script. Imported modules of @var{gexp} are looked up in @var{module-path}.
11576 This is the declarative counterpart of @code{gexp->script}.
11579 @deffn {Monadic Procedure} gexp->file @var{name} @var{exp} @
11580 [#:set-load-path? #t] [#:module-path %load-path] @
11582 [#:guile (default-guile)]
11583 Return a derivation that builds a file @var{name} containing @var{exp}.
11584 When @var{splice?} is true, @var{exp} is considered to be a list of
11585 expressions that will be spliced in the resulting file.
11587 When @var{set-load-path?} is true, emit code in the resulting file to
11588 set @code{%load-path} and @code{%load-compiled-path} to honor
11589 @var{exp}'s imported modules. Look up @var{exp}'s modules in
11592 The resulting file holds references to all the dependencies of @var{exp}
11593 or a subset thereof.
11596 @deffn {Scheme Procedure} scheme-file @var{name} @var{exp} @
11597 [#:splice? #f] [#:set-load-path? #t]
11598 Return an object representing the Scheme file @var{name} that contains
11601 This is the declarative counterpart of @code{gexp->file}.
11604 @deffn {Monadic Procedure} text-file* @var{name} @var{text} @dots{}
11605 Return as a monadic value a derivation that builds a text file
11606 containing all of @var{text}. @var{text} may list, in addition to
11607 strings, objects of any type that can be used in a gexp: packages,
11608 derivations, local file objects, etc. The resulting store file holds
11609 references to all these.
11611 This variant should be preferred over @code{text-file} anytime the file
11612 to create will reference items from the store. This is typically the
11613 case when building a configuration file that embeds store file names,
11617 (define (profile.sh)
11618 ;; Return the name of a shell script in the store that
11619 ;; initializes the 'PATH' environment variable.
11620 (text-file* "profile.sh"
11621 "export PATH=" coreutils "/bin:"
11622 grep "/bin:" sed "/bin\n"))
11625 In this example, the resulting @file{/gnu/store/@dots{}-profile.sh} file
11626 will reference @var{coreutils}, @var{grep}, and @var{sed}, thereby
11627 preventing them from being garbage-collected during its lifetime.
11630 @deffn {Scheme Procedure} mixed-text-file @var{name} @var{text} @dots{}
11631 Return an object representing store file @var{name} containing
11632 @var{text}. @var{text} is a sequence of strings and file-like objects,
11636 (mixed-text-file "profile"
11637 "export PATH=" coreutils "/bin:" grep "/bin")
11640 This is the declarative counterpart of @code{text-file*}.
11643 @deffn {Scheme Procedure} file-union @var{name} @var{files}
11644 Return a @code{<computed-file>} that builds a directory containing all of @var{files}.
11645 Each item in @var{files} must be a two-element list where the first element is the
11646 file name to use in the new directory, and the second element is a gexp
11647 denoting the target file. Here's an example:
11651 `(("hosts" ,(plain-file "hosts"
11652 "127.0.0.1 localhost"))
11653 ("bashrc" ,(plain-file "bashrc"
11654 "alias ls='ls --color=auto'"))))
11657 This yields an @code{etc} directory containing these two files.
11660 @deffn {Scheme Procedure} directory-union @var{name} @var{things}
11661 Return a directory that is the union of @var{things}, where @var{things} is a list of
11662 file-like objects denoting directories. For example:
11665 (directory-union "guile+emacs" (list guile emacs))
11668 yields a directory that is the union of the @code{guile} and @code{emacs} packages.
11671 @deffn {Scheme Procedure} file-append @var{obj} @var{suffix} @dots{}
11672 Return a file-like object that expands to the concatenation of @var{obj}
11673 and @var{suffix}, where @var{obj} is a lowerable object and each
11674 @var{suffix} is a string.
11676 As an example, consider this gexp:
11679 (gexp->script "run-uname"
11680 #~(system* #$(file-append coreutils
11684 The same effect could be achieved with:
11687 (gexp->script "run-uname"
11688 #~(system* (string-append #$coreutils
11692 There is one difference though: in the @code{file-append} case, the
11693 resulting script contains the absolute file name as a string, whereas in
11694 the second case, the resulting script contains a @code{(string-append
11695 @dots{})} expression to construct the file name @emph{at run time}.
11698 @deffn {Scheme Syntax} let-system @var{system} @var{body}@dots{}
11699 @deffnx {Scheme Syntax} let-system (@var{system} @var{target}) @var{body}@dots{}
11700 Bind @var{system} to the currently targeted system---e.g.,
11701 @code{"x86_64-linux"}---within @var{body}.
11703 In the second case, additionally bind @var{target} to the current
11704 cross-compilation target---a GNU triplet such as
11705 @code{"arm-linux-gnueabihf"}---or @code{#f} if we are not
11708 @code{let-system} is useful in the occasional case where the object
11709 spliced into the gexp depends on the target system, as in this example:
11713 #+(let-system system
11714 (cond ((string-prefix? "armhf-" system)
11715 (file-append qemu "/bin/qemu-system-arm"))
11716 ((string-prefix? "x86_64-" system)
11717 (file-append qemu "/bin/qemu-system-x86_64"))
11719 (error "dunno!"))))
11720 "-net" "user" #$image)
11724 @deffn {Scheme Syntax} with-parameters ((@var{parameter} @var{value}) @dots{}) @var{exp}
11725 This macro is similar to the @code{parameterize} form for
11726 dynamically-bound @dfn{parameters} (@pxref{Parameters,,, guile, GNU
11727 Guile Reference Manual}). The key difference is that it takes effect
11728 when the file-like object returned by @var{exp} is lowered to a
11729 derivation or store item.
11731 A typical use of @code{with-parameters} is to force the system in effect
11732 for a given object:
11735 (with-parameters ((%current-system "i686-linux"))
11739 The example above returns an object that corresponds to the i686 build
11740 of Coreutils, regardless of the current value of @code{%current-system}.
11744 Of course, in addition to gexps embedded in ``host'' code, there are
11745 also modules containing build tools. To make it clear that they are
11746 meant to be used in the build stratum, these modules are kept in the
11747 @code{(guix build @dots{})} name space.
11749 @cindex lowering, of high-level objects in gexps
11750 Internally, high-level objects are @dfn{lowered}, using their compiler,
11751 to either derivations or store items. For instance, lowering a package
11752 yields a derivation, and lowering a @code{plain-file} yields a store
11753 item. This is achieved using the @code{lower-object} monadic procedure.
11755 @deffn {Monadic Procedure} lower-object @var{obj} [@var{system}] @
11757 Return as a value in @code{%store-monad} the derivation or store item
11758 corresponding to @var{obj} for @var{system}, cross-compiling for
11759 @var{target} if @var{target} is true. @var{obj} must be an object that
11760 has an associated gexp compiler, such as a @code{<package>}.
11763 @deffn {Procedure} gexp->approximate-sexp @var{gexp}
11764 Sometimes, it may be useful to convert a G-exp into a S-exp. For
11765 example, some linters (@pxref{Invoking guix lint}) peek into the build
11766 phases of a package to detect potential problems. This conversion can
11767 be achieved with this procedure. However, some information can be lost
11768 in the process. More specifically, lowerable objects will be silently
11769 replaced with some arbitrary object -- currently the list
11770 @code{(*approximate*)}, but this may change.
11773 @node Invoking guix repl
11774 @section Invoking @command{guix repl}
11776 @cindex REPL, read-eval-print loop, script
11777 The @command{guix repl} command makes it easier to program Guix in Guile
11778 by launching a Guile @dfn{read-eval-print loop} (REPL) for interactive
11779 programming (@pxref{Using Guile Interactively,,, guile,
11780 GNU Guile Reference Manual}), or by running Guile scripts
11781 (@pxref{Running Guile Scripts,,, guile,
11782 GNU Guile Reference Manual}).
11783 Compared to just launching the @command{guile}
11784 command, @command{guix repl} guarantees that all the Guix modules and all its
11785 dependencies are available in the search path.
11787 The general syntax is:
11790 guix repl @var{options} [@var{file} @var{args}]
11793 When a @var{file} argument is provided, @var{file} is
11794 executed as a Guile scripts:
11797 guix repl my-script.scm
11800 To pass arguments to the script, use @code{--} to prevent them from
11801 being interpreted as arguments to @command{guix repl} itself:
11804 guix repl -- my-script.scm --input=foo.txt
11807 To make a script executable directly from the shell, using the guix
11808 executable that is on the user's search path, add the following two
11809 lines at the top of the script:
11812 @code{#!/usr/bin/env -S guix repl --}
11816 Without a file name argument, a Guile REPL is started, allowing for
11817 interactive use (@pxref{Using Guix Interactively}):
11821 scheme@@(guile-user)> ,use (gnu packages base)
11822 scheme@@(guile-user)> coreutils
11823 $1 = #<package coreutils@@8.29 gnu/packages/base.scm:327 3e28300>
11827 In addition, @command{guix repl} implements a simple machine-readable REPL
11828 protocol for use by @code{(guix inferior)}, a facility to interact with
11829 @dfn{inferiors}, separate processes running a potentially different revision
11832 The available options are as follows:
11835 @item --type=@var{type}
11836 @itemx -t @var{type}
11837 Start a REPL of the given @var{TYPE}, which can be one of the following:
11841 This is default, and it spawns a standard full-featured Guile REPL.
11843 Spawn a REPL that uses the machine-readable protocol. This is the protocol
11844 that the @code{(guix inferior)} module speaks.
11847 @item --listen=@var{endpoint}
11848 By default, @command{guix repl} reads from standard input and writes to
11849 standard output. When this option is passed, it will instead listen for
11850 connections on @var{endpoint}. Here are examples of valid options:
11853 @item --listen=tcp:37146
11854 Accept connections on localhost on port 37146.
11856 @item --listen=unix:/tmp/socket
11857 Accept connections on the Unix-domain socket @file{/tmp/socket}.
11860 @item --load-path=@var{directory}
11861 @itemx -L @var{directory}
11862 Add @var{directory} to the front of the package module search path
11863 (@pxref{Package Modules}).
11865 This allows users to define their own packages and make them visible to
11866 the script or REPL.
11869 Inhibit loading of the @file{~/.guile} file. By default, that
11870 configuration file is loaded when spawning a @code{guile} REPL.
11873 @node Using Guix Interactively
11874 @section Using Guix Interactively
11876 @cindex interactive use
11877 @cindex REPL, read-eval-print loop
11878 The @command{guix repl} command gives you access to a warm and friendly
11879 @dfn{read-eval-print loop} (REPL) (@pxref{Invoking guix repl}). If
11880 you're getting into Guix programming---defining your own packages,
11881 writing manifests, defining services for Guix System or Guix Home,
11882 etc.---you will surely find it convenient to toy with ideas at the REPL.
11884 If you use Emacs, the most convenient way to do that is with Geiser
11885 (@pxref{The Perfect Setup}), but you do not have to use Emacs to enjoy
11886 the REPL@. When using @command{guix repl} or @command{guile} in the
11887 terminal, we recommend using Readline for completion and Colorized to
11888 get colorful output. To do that, you can run:
11891 guix install guile guile-readline guile-colorized
11895 ... and then create a @file{.guile} file in your home directory containing
11899 (use-modules (ice-9 readline) (ice-9 colorized))
11901 (activate-readline)
11902 (activate-colorized)
11905 The REPL lets you evaluate Scheme code; you type a Scheme expression at
11906 the prompt, and the REPL prints what it evaluates to:
11910 scheme@@(guix-user)> (+ 2 3)
11912 scheme@@(guix-user)> (string-append "a" "b")
11916 It becomes interesting when you start fiddling with Guix at the REPL.
11917 The first thing you'll want to do is to ``import'' the @code{(guix)}
11918 module, which gives access to the main part of the programming
11919 interface, and perhaps a bunch of useful Guix modules. You could type
11920 @code{(use-modules (guix))}, which is valid Scheme code to import a
11921 module (@pxref{Using Guile Modules,,, guile, GNU Guile Reference
11922 Manual}), but the REPL provides the @code{use} @dfn{command} as a
11923 shorthand notation (@pxref{REPL Commands,,, guile, GNU Guile Reference
11927 scheme@@(guix-user)> ,use (guix)
11928 scheme@@(guix-user)> ,use (gnu packages base)
11931 Notice that REPL commands are introduced by a leading comma. A REPL
11932 command like @code{use} is not valid Scheme code; it's interpreted
11933 specially by the REPL.
11935 Guix extends the Guile REPL with additional commands for convenience.
11936 Among those, the @code{build} command comes in handy: it ensures that
11937 the given file-like object is built, building it if needed, and returns
11938 its output file name(s). In the example below, we build the
11939 @code{coreutils} and @code{grep} packages, as well as a ``computed
11940 file'' (@pxref{G-Expressions, @code{computed-file}}), and we use the
11941 @code{scandir} procedure to list the files in Grep's @code{/bin}
11945 scheme@@(guix-user)> ,build coreutils
11946 $1 = "/gnu/store/@dots{}-coreutils-8.32-debug"
11947 $2 = "/gnu/store/@dots{}-coreutils-8.32"
11948 scheme@@(guix-user)> ,build grep
11949 $3 = "/gnu/store/@dots{}-grep-3.6"
11950 scheme@@(guix-user)> ,build (computed-file "x" #~(mkdir #$output))
11951 building /gnu/store/@dots{}-x.drv...
11952 $4 = "/gnu/store/@dots{}-x"
11953 scheme@@(guix-user)> ,use(ice-9 ftw)
11954 scheme@@(guix-user)> (scandir (string-append $3 "/bin"))
11955 $5 = ("." ".." "egrep" "fgrep" "grep")
11958 At a lower-level, a useful command is @code{lower}: it takes a file-like
11959 object and ``lowers'' it into a derivation (@pxref{Derivations}) or a
11963 scheme@@(guix-user)> ,lower grep
11964 $6 = #<derivation /gnu/store/@dots{}-grep-3.6.drv => /gnu/store/@dots{}-grep-3.6 7f0e639115f0>
11965 scheme@@(guix-user)> ,lower (plain-file "x" "Hello!")
11966 $7 = "/gnu/store/@dots{}-x"
11969 The full list of REPL commands can be seen by typing @code{,help guix}
11970 and is given below for reference.
11972 @deffn {REPL command} build @var{object}
11973 Lower @var{object} and build it if it's not already built, returning its
11974 output file name(s).
11977 @deffn {REPL command} lower @var{object}
11978 Lower @var{object} into a derivation or store file name and return it.
11981 @deffn {REPL command} verbosity @var{level}
11982 Change build verbosity to @var{level}.
11984 This is similar to the @option{--verbosity} command-line option
11985 (@pxref{Common Build Options}): level 0 means total silence, level 1
11986 shows build events only, and higher levels print build logs.
11989 @deffn {REPL command} run-in-store @var{exp}
11990 Run @var{exp}, a monadic expresssion, through the store monad.
11991 @xref{The Store Monad}, for more information.
11994 @deffn {REPL command} enter-store-monad
11995 Enter a new REPL to evaluate monadic expressions (@pxref{The Store
11996 Monad}). You can quit this ``inner'' REPL by typing @code{,q}.
11999 @c *********************************************************************
12003 This section describes Guix command-line utilities. Some of them are
12004 primarily targeted at developers and users who write new package
12005 definitions, while others are more generally useful. They complement
12006 the Scheme programming interface of Guix in a convenient way.
12009 * Invoking guix build:: Building packages from the command line.
12010 * Invoking guix edit:: Editing package definitions.
12011 * Invoking guix download:: Downloading a file and printing its hash.
12012 * Invoking guix hash:: Computing the cryptographic hash of a file.
12013 * Invoking guix import:: Importing package definitions.
12014 * Invoking guix refresh:: Updating package definitions.
12015 * Invoking guix style:: Styling package definitions.
12016 * Invoking guix lint:: Finding errors in package definitions.
12017 * Invoking guix size:: Profiling disk usage.
12018 * Invoking guix graph:: Visualizing the graph of packages.
12019 * Invoking guix publish:: Sharing substitutes.
12020 * Invoking guix challenge:: Challenging substitute servers.
12021 * Invoking guix copy:: Copying to and from a remote store.
12022 * Invoking guix container:: Process isolation.
12023 * Invoking guix weather:: Assessing substitute availability.
12024 * Invoking guix processes:: Listing client processes.
12027 @node Invoking guix build
12028 @section Invoking @command{guix build}
12030 @cindex package building
12031 @cindex @command{guix build}
12032 The @command{guix build} command builds packages or derivations and
12033 their dependencies, and prints the resulting store paths. Note that it
12034 does not modify the user's profile---this is the job of the
12035 @command{guix package} command (@pxref{Invoking guix package}). Thus,
12036 it is mainly useful for distribution developers.
12038 The general syntax is:
12041 guix build @var{options} @var{package-or-derivation}@dots{}
12044 As an example, the following command builds the latest versions of Emacs
12045 and of Guile, displays their build logs, and finally displays the
12046 resulting directories:
12049 guix build emacs guile
12052 Similarly, the following command builds all the available packages:
12055 guix build --quiet --keep-going \
12056 $(guix package -A | awk '@{ print $1 "@@" $2 @}')
12059 @var{package-or-derivation} may be either the name of a package found in
12060 the software distribution such as @code{coreutils} or
12061 @code{coreutils@@8.20}, or a derivation such as
12062 @file{/gnu/store/@dots{}-coreutils-8.19.drv}. In the former case, a
12063 package with the corresponding name (and optionally version) is searched
12064 for among the GNU distribution modules (@pxref{Package Modules}).
12066 Alternatively, the @option{--expression} option may be used to specify a
12067 Scheme expression that evaluates to a package; this is useful when
12068 disambiguating among several same-named packages or package variants is
12071 There may be zero or more @var{options}. The available options are
12072 described in the subsections below.
12075 * Common Build Options:: Build options for most commands.
12076 * Package Transformation Options:: Creating variants of packages.
12077 * Additional Build Options:: Options specific to 'guix build'.
12078 * Debugging Build Failures:: Real life packaging experience.
12081 @node Common Build Options
12082 @subsection Common Build Options
12084 A number of options that control the build process are common to
12085 @command{guix build} and other commands that can spawn builds, such as
12086 @command{guix package} or @command{guix archive}. These are the
12091 @item --load-path=@var{directory}
12092 @itemx -L @var{directory}
12093 Add @var{directory} to the front of the package module search path
12094 (@pxref{Package Modules}).
12096 This allows users to define their own packages and make them visible to
12097 the command-line tools.
12099 @item --keep-failed
12101 Keep the build tree of failed builds. Thus, if a build fails, its build
12102 tree is kept under @file{/tmp}, in a directory whose name is shown at
12103 the end of the build log. This is useful when debugging build issues.
12104 @xref{Debugging Build Failures}, for tips and tricks on how to debug
12107 This option implies @option{--no-offload}, and it has no effect when
12108 connecting to a remote daemon with a @code{guix://} URI (@pxref{The
12109 Store, the @env{GUIX_DAEMON_SOCKET} variable}).
12113 Keep going when some of the derivations fail to build; return only once
12114 all the builds have either completed or failed.
12116 The default behavior is to stop as soon as one of the specified
12117 derivations has failed.
12121 Do not build the derivations.
12123 @anchor{fallback-option}
12125 When substituting a pre-built binary fails, fall back to building
12126 packages locally (@pxref{Substitution Failure}).
12128 @item --substitute-urls=@var{urls}
12129 @anchor{client-substitute-urls}
12130 Consider @var{urls} the whitespace-separated list of substitute source
12131 URLs, overriding the default list of URLs of @command{guix-daemon}
12132 (@pxref{daemon-substitute-urls,, @command{guix-daemon} URLs}).
12134 This means that substitutes may be downloaded from @var{urls}, provided
12135 they are signed by a key authorized by the system administrator
12136 (@pxref{Substitutes}).
12138 When @var{urls} is the empty string, substitutes are effectively
12141 @item --no-substitutes
12142 Do not use substitutes for build products. That is, always build things
12143 locally instead of allowing downloads of pre-built binaries
12144 (@pxref{Substitutes}).
12147 Do not ``graft'' packages. In practice, this means that package updates
12148 available as grafts are not applied. @xref{Security Updates}, for more
12149 information on grafts.
12151 @item --rounds=@var{n}
12152 Build each derivation @var{n} times in a row, and raise an error if
12153 consecutive build results are not bit-for-bit identical.
12155 This is a useful way to detect non-deterministic builds processes.
12156 Non-deterministic build processes are a problem because they make it
12157 practically impossible for users to @emph{verify} whether third-party
12158 binaries are genuine. @xref{Invoking guix challenge}, for more.
12160 When used in conjunction with @option{--keep-failed}, the differing
12161 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
12162 This makes it easy to look for differences between the two results.
12165 Do not use offload builds to other machines (@pxref{Daemon Offload
12166 Setup}). That is, always build things locally instead of offloading
12167 builds to remote machines.
12169 @item --max-silent-time=@var{seconds}
12170 When the build or substitution process remains silent for more than
12171 @var{seconds}, terminate it and report a build failure.
12173 By default, the daemon's setting is honored (@pxref{Invoking
12174 guix-daemon, @option{--max-silent-time}}).
12176 @item --timeout=@var{seconds}
12177 Likewise, when the build or substitution process lasts for more than
12178 @var{seconds}, terminate it and report a build failure.
12180 By default, the daemon's setting is honored (@pxref{Invoking
12181 guix-daemon, @option{--timeout}}).
12183 @c Note: This option is actually not part of %standard-build-options but
12184 @c most programs honor it.
12185 @cindex verbosity, of the command-line tools
12186 @cindex build logs, verbosity
12187 @item -v @var{level}
12188 @itemx --verbosity=@var{level}
12189 Use the given verbosity @var{level}, an integer. Choosing 0 means that
12190 no output is produced, 1 is for quiet output; 2 is similar to 1 but it
12191 additionally displays download URLs; 3 shows all the build log output on
12194 @item --cores=@var{n}
12196 Allow the use of up to @var{n} CPU cores for the build. The special
12197 value @code{0} means to use as many CPU cores as available.
12199 @item --max-jobs=@var{n}
12201 Allow at most @var{n} build jobs in parallel. @xref{Invoking
12202 guix-daemon, @option{--max-jobs}}, for details about this option and the
12203 equivalent @command{guix-daemon} option.
12205 @item --debug=@var{level}
12206 Produce debugging output coming from the build daemon. @var{level} must be an
12207 integer between 0 and 5; higher means more verbose output. Setting a level of
12208 4 or more may be helpful when debugging setup issues with the build daemon.
12212 Behind the scenes, @command{guix build} is essentially an interface to
12213 the @code{package-derivation} procedure of the @code{(guix packages)}
12214 module, and to the @code{build-derivations} procedure of the @code{(guix
12215 derivations)} module.
12217 In addition to options explicitly passed on the command line,
12218 @command{guix build} and other @command{guix} commands that support
12219 building honor the @env{GUIX_BUILD_OPTIONS} environment variable.
12221 @defvr {Environment Variable} GUIX_BUILD_OPTIONS
12222 Users can define this variable to a list of command line options that
12223 will automatically be used by @command{guix build} and other
12224 @command{guix} commands that can perform builds, as in the example
12228 $ export GUIX_BUILD_OPTIONS="--no-substitutes -c 2 -L /foo/bar"
12231 These options are parsed independently, and the result is appended to
12232 the parsed command-line options.
12236 @node Package Transformation Options
12237 @subsection Package Transformation Options
12239 @cindex package variants
12240 Another set of command-line options supported by @command{guix build}
12241 and also @command{guix package} are @dfn{package transformation
12242 options}. These are options that make it possible to define @dfn{package
12243 variants}---for instance, packages built from different source code.
12244 This is a convenient way to create customized packages on the fly
12245 without having to type in the definitions of package variants
12246 (@pxref{Defining Packages}).
12248 Package transformation options are preserved across upgrades:
12249 @command{guix upgrade} attempts to apply transformation options
12250 initially used when creating the profile to the upgraded packages.
12252 The available options are listed below. Most commands support them and
12253 also support a @option{--help-transform} option that lists all the
12254 available options and a synopsis (these options are not shown in the
12255 @option{--help} output for brevity).
12259 @cindex performance, tuning code
12260 @cindex optimization, of package code
12261 @cindex tuning, of package code
12262 @cindex SIMD support
12263 @cindex tunable packages
12264 @cindex package multi-versioning
12265 @item --tune[=@var{cpu}]
12266 Use versions of the packages marked as ``tunable'' optimized for
12267 @var{cpu}. When @var{cpu} is @code{native}, or when it is omitted, tune
12268 for the CPU on which the @command{guix} command is running.
12270 Valid @var{cpu} names are those recognized by the underlying compiler,
12271 by default the GNU Compiler Collection. On x86_64 processors, this
12272 includes CPU names such as @code{nehalem}, @code{haswell}, and
12273 @code{skylake} (@pxref{x86 Options, @code{-march},, gcc, Using the GNU
12274 Compiler Collection (GCC)}).
12276 As new generations of CPUs come out, they augment the standard
12277 instruction set architecture (ISA) with additional instructions, in
12278 particular instructions for single-instruction/multiple-data (SIMD)
12279 parallel processing. For example, while Core2 and Skylake CPUs both
12280 implement the x86_64 ISA, only the latter supports AVX2 SIMD
12283 The primary gain one can expect from @option{--tune} is for programs
12284 that can make use of those SIMD capabilities @emph{and} that do not
12285 already have a mechanism to select the right optimized code at run time.
12286 Packages that have the @code{tunable?} property set are considered
12287 @dfn{tunable packages} by the @option{--tune} option; a package
12288 definition with the property set looks like this:
12292 (name "hello-simd")
12295 ;; This package may benefit from SIMD extensions so
12296 ;; mark it as "tunable".
12297 (properties '((tunable? . #t))))
12300 Other packages are not considered tunable. This allows Guix to use
12301 generic binaries in the cases where tuning for a specific CPU is
12302 unlikely to provide any gain.
12304 Tuned packages are built with @code{-march=@var{CPU}}; under the hood,
12305 the @option{-march} option is passed to the actual wrapper by a compiler
12306 wrapper. Since the build machine may not be able to run code for the
12307 target CPU micro-architecture, the test suite is not run when building a
12310 To reduce rebuilds to the minimum, tuned packages are @emph{grafted}
12311 onto packages that depend on them (@pxref{Security Updates, grafts}).
12312 Thus, using @option{--no-grafts} cancels the effect of @option{--tune}.
12314 We call this technique @dfn{package multi-versioning}: several variants
12315 of tunable packages may be built, one for each CPU variant. It is the
12316 coarse-grain counterpart of @dfn{function multi-versioning} as
12317 implemented by the GNU tool chain (@pxref{Function Multiversioning,,,
12318 gcc, Using the GNU Compiler Collection (GCC)}).
12320 @item --with-source=@var{source}
12321 @itemx --with-source=@var{package}=@var{source}
12322 @itemx --with-source=@var{package}@@@var{version}=@var{source}
12323 Use @var{source} as the source of @var{package}, and @var{version} as
12324 its version number.
12325 @var{source} must be a file name or a URL, as for @command{guix
12326 download} (@pxref{Invoking guix download}).
12328 When @var{package} is omitted,
12329 it is taken to be the package name specified on the
12330 command line that matches the base of @var{source}---e.g.,
12331 if @var{source} is @code{/src/guile-2.0.10.tar.gz}, the corresponding
12332 package is @code{guile}.
12334 Likewise, when @var{version} is omitted, the version string is inferred from
12335 @var{source}; in the previous example, it is @code{2.0.10}.
12337 This option allows users to try out versions of packages other than the
12338 one provided by the distribution. The example below downloads
12339 @file{ed-1.7.tar.gz} from a GNU mirror and uses that as the source for
12340 the @code{ed} package:
12343 guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz
12346 As a developer, @option{--with-source} makes it easy to test release
12350 guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz
12353 @dots{} or to build from a checkout in a pristine environment:
12356 $ git clone git://git.sv.gnu.org/guix.git
12357 $ guix build guix --with-source=guix@@1.0=./guix
12360 @item --with-input=@var{package}=@var{replacement}
12361 Replace dependency on @var{package} by a dependency on
12362 @var{replacement}. @var{package} must be a package name, and
12363 @var{replacement} must be a package specification such as @code{guile}
12364 or @code{guile@@1.8}.
12366 For instance, the following command builds Guix, but replaces its
12367 dependency on the current stable version of Guile with a dependency on
12368 the legacy version of Guile, @code{guile@@2.0}:
12371 guix build --with-input=guile=guile@@2.0 guix
12374 This is a recursive, deep replacement. So in this example, both
12375 @code{guix} and its dependency @code{guile-json} (which also depends on
12376 @code{guile}) get rebuilt against @code{guile@@2.0}.
12378 This is implemented using the @code{package-input-rewriting} Scheme
12379 procedure (@pxref{Defining Packages, @code{package-input-rewriting}}).
12381 @item --with-graft=@var{package}=@var{replacement}
12382 This is similar to @option{--with-input} but with an important difference:
12383 instead of rebuilding the whole dependency chain, @var{replacement} is
12384 built and then @dfn{grafted} onto the binaries that were initially
12385 referring to @var{package}. @xref{Security Updates}, for more
12386 information on grafts.
12388 For example, the command below grafts version 3.5.4 of GnuTLS onto Wget
12389 and all its dependencies, replacing references to the version of GnuTLS
12390 they currently refer to:
12393 guix build --with-graft=gnutls=gnutls@@3.5.4 wget
12396 This has the advantage of being much faster than rebuilding everything.
12397 But there is a caveat: it works if and only if @var{package} and
12398 @var{replacement} are strictly compatible---for example, if they provide
12399 a library, the application binary interface (ABI) of those libraries
12400 must be compatible. If @var{replacement} is somehow incompatible with
12401 @var{package}, then the resulting package may be unusable. Use with
12404 @cindex debugging info, rebuilding
12405 @item --with-debug-info=@var{package}
12406 Build @var{package} in a way that preserves its debugging info and graft
12407 it onto packages that depend on it. This is useful if @var{package}
12408 does not already provide debugging info as a @code{debug} output
12409 (@pxref{Installing Debugging Files}).
12411 For example, suppose you're experiencing a crash in Inkscape and would
12412 like to see what's up in GLib, a library deep down in Inkscape's
12413 dependency graph. GLib lacks a @code{debug} output, so debugging is
12414 tough. Fortunately, you rebuild GLib with debugging info and tack it on
12418 guix install inkscape --with-debug-info=glib
12421 Only GLib needs to be recompiled so this takes a reasonable amount of
12422 time. @xref{Installing Debugging Files}, for more info.
12425 Under the hood, this option works by passing the @samp{#:strip-binaries?
12426 #f} to the build system of the package of interest (@pxref{Build
12427 Systems}). Most build systems support that option but some do not. In
12428 that case, an error is raised.
12430 Likewise, if a C/C++ package is built without @code{-g} (which is rarely
12431 the case), debugging info will remain unavailable even when
12432 @code{#:strip-binaries?} is false.
12435 @cindex tool chain, changing the build tool chain of a package
12436 @item --with-c-toolchain=@var{package}=@var{toolchain}
12437 This option changes the compilation of @var{package} and everything that
12438 depends on it so that they get built with @var{toolchain} instead of the
12439 default GNU tool chain for C/C++.
12441 Consider this example:
12444 guix build octave-cli \
12445 --with-c-toolchain=fftw=gcc-toolchain@@10 \
12446 --with-c-toolchain=fftwf=gcc-toolchain@@10
12449 The command above builds a variant of the @code{fftw} and @code{fftwf}
12450 packages using version 10 of @code{gcc-toolchain} instead of the default
12451 tool chain, and then builds a variant of the GNU@tie{}Octave
12452 command-line interface using them. GNU@tie{}Octave itself is also built
12453 with @code{gcc-toolchain@@10}.
12455 This other example builds the Hardware Locality (@code{hwloc}) library
12456 and its dependents up to @code{intel-mpi-benchmarks} with the Clang C
12460 guix build --with-c-toolchain=hwloc=clang-toolchain \
12461 intel-mpi-benchmarks
12465 There can be application binary interface (ABI) incompatibilities among
12466 tool chains. This is particularly true of the C++ standard library and
12467 run-time support libraries such as that of OpenMP@. By rebuilding all
12468 dependents with the same tool chain, @option{--with-c-toolchain} minimizes
12469 the risks of incompatibility but cannot entirely eliminate them. Choose
12470 @var{package} wisely.
12473 @item --with-git-url=@var{package}=@var{url}
12474 @cindex Git, using the latest commit
12475 @cindex latest commit, building
12476 Build @var{package} from the latest commit of the @code{master} branch of the
12477 Git repository at @var{url}. Git sub-modules of the repository are fetched,
12480 For example, the following command builds the NumPy Python library against the
12481 latest commit of the master branch of Python itself:
12484 guix build python-numpy \
12485 --with-git-url=python=https://github.com/python/cpython
12488 This option can also be combined with @option{--with-branch} or
12489 @option{--with-commit} (see below).
12491 @cindex continuous integration
12492 Obviously, since it uses the latest commit of the given branch, the result of
12493 such a command varies over time. Nevertheless it is a convenient way to
12494 rebuild entire software stacks against the latest commit of one or more
12495 packages. This is particularly useful in the context of continuous
12498 Checkouts are kept in a cache under @file{~/.cache/guix/checkouts} to speed up
12499 consecutive accesses to the same repository. You may want to clean it up once
12500 in a while to save disk space.
12502 @item --with-branch=@var{package}=@var{branch}
12503 Build @var{package} from the latest commit of @var{branch}. If the
12504 @code{source} field of @var{package} is an origin with the @code{git-fetch}
12505 method (@pxref{origin Reference}) or a @code{git-checkout} object, the
12506 repository URL is taken from that @code{source}. Otherwise you have to use
12507 @option{--with-git-url} to specify the URL of the Git repository.
12509 For instance, the following command builds @code{guile-sqlite3} from the
12510 latest commit of its @code{master} branch, and then builds @code{guix} (which
12511 depends on it) and @code{cuirass} (which depends on @code{guix}) against this
12512 specific @code{guile-sqlite3} build:
12515 guix build --with-branch=guile-sqlite3=master cuirass
12518 @item --with-commit=@var{package}=@var{commit}
12519 This is similar to @option{--with-branch}, except that it builds from
12520 @var{commit} rather than the tip of a branch. @var{commit} must be a valid
12521 Git commit SHA1 identifier, a tag, or a @command{git describe} style
12522 identifier such as @code{1.0-3-gabc123}.
12524 @item --with-patch=@var{package}=@var{file}
12525 Add @var{file} to the list of patches applied to @var{package}, where
12526 @var{package} is a spec such as @code{python@@3.8} or @code{glibc}.
12527 @var{file} must contain a patch; it is applied with the flags specified
12528 in the @code{origin} of @var{package} (@pxref{origin Reference}), which
12529 by default includes @code{-p1} (@pxref{patch Directories,,, diffutils,
12530 Comparing and Merging Files}).
12532 As an example, the command below rebuilds Coreutils with the GNU C
12533 Library (glibc) patched with the given patch:
12536 guix build coreutils --with-patch=glibc=./glibc-frob.patch
12539 In this example, glibc itself as well as everything that leads to
12540 Coreutils in the dependency graph is rebuilt.
12542 @cindex upstream, latest version
12543 @item --with-latest=@var{package}
12544 So you like living on the bleeding edge? This option is for you! It
12545 replaces occurrences of @var{package} in the dependency graph with its
12546 latest upstream version, as reported by @command{guix refresh}
12547 (@pxref{Invoking guix refresh}).
12549 It does so by determining the latest upstream release of @var{package}
12550 (if possible), downloading it, and authenticating it @emph{if} it comes
12551 with an OpenPGP signature.
12553 As an example, the command below builds Guix against the latest version
12557 guix build guix --with-latest=guile-json
12560 There are limitations. First, in cases where the tool cannot or does
12561 not know how to authenticate source code, you are at risk of running
12562 malicious code; a warning is emitted in this case. Second, this option
12563 simply changes the source used in the existing package definitions,
12564 which is not always sufficient: there might be additional dependencies
12565 that need to be added, patches to apply, and more generally the quality
12566 assurance work that Guix developers normally do will be missing.
12568 You've been warned! In all the other cases, it's a snappy way to stay
12569 on top. We encourage you to submit patches updating the actual package
12570 definitions once you have successfully tested an upgrade
12571 (@pxref{Contributing}).
12573 @cindex test suite, skipping
12574 @item --without-tests=@var{package}
12575 Build @var{package} without running its tests. This can be useful in
12576 situations where you want to skip the lengthy test suite of a
12577 intermediate package, or if a package's test suite fails in a
12578 non-deterministic fashion. It should be used with care because running
12579 the test suite is a good way to ensure a package is working as intended.
12581 Turning off tests leads to a different store item. Consequently, when
12582 using this option, anything that depends on @var{package} must be
12583 rebuilt, as in this example:
12586 guix install --without-tests=python python-notebook
12589 The command above installs @code{python-notebook} on top of
12590 @code{python} built without running its test suite. To do so, it also
12591 rebuilds everything that depends on @code{python}, including
12592 @code{python-notebook} itself.
12594 Internally, @option{--without-tests} relies on changing the
12595 @code{#:tests?} option of a package's @code{check} phase (@pxref{Build
12596 Systems}). Note that some packages use a customized @code{check} phase
12597 that does not respect a @code{#:tests? #f} setting. Therefore,
12598 @option{--without-tests} has no effect on these packages.
12602 Wondering how to achieve the same effect using Scheme code, for example
12603 in your manifest, or how to write your own package transformation?
12604 @xref{Defining Package Variants}, for an overview of the programming
12605 interfaces available.
12607 @node Additional Build Options
12608 @subsection Additional Build Options
12610 The command-line options presented below are specific to @command{guix
12617 Build quietly, without displaying the build log; this is equivalent to
12618 @option{--verbosity=0}. Upon completion, the build log is kept in @file{/var}
12619 (or similar) and can always be retrieved using the @option{--log-file} option.
12621 @item --file=@var{file}
12622 @itemx -f @var{file}
12623 Build the package, derivation, or other file-like object that the code within
12624 @var{file} evaluates to (@pxref{G-Expressions, file-like objects}).
12626 As an example, @var{file} might contain a package definition like this
12627 (@pxref{Defining Packages}):
12630 @include package-hello.scm
12633 The @var{file} may also contain a JSON representation of one or more
12634 package definitions. Running @code{guix build -f} on @file{hello.json}
12635 with the following contents would result in building the packages
12636 @code{myhello} and @code{greeter}:
12639 @verbatiminclude package-hello.json
12642 @item --manifest=@var{manifest}
12643 @itemx -m @var{manifest}
12644 Build all packages listed in the given @var{manifest}
12645 (@pxref{profile-manifest, @option{--manifest}}).
12647 @item --expression=@var{expr}
12648 @itemx -e @var{expr}
12649 Build the package or derivation @var{expr} evaluates to.
12651 For example, @var{expr} may be @code{(@@ (gnu packages guile)
12652 guile-1.8)}, which unambiguously designates this specific variant of
12653 version 1.8 of Guile.
12655 Alternatively, @var{expr} may be a G-expression, in which case it is used
12656 as a build program passed to @code{gexp->derivation}
12657 (@pxref{G-Expressions}).
12659 Lastly, @var{expr} may refer to a zero-argument monadic procedure
12660 (@pxref{The Store Monad}). The procedure must return a derivation as a
12661 monadic value, which is then passed through @code{run-with-store}.
12665 Build the source derivations of the packages, rather than the packages
12668 For instance, @code{guix build -S gcc} returns something like
12669 @file{/gnu/store/@dots{}-gcc-4.7.2.tar.bz2}, which is the GCC
12672 The returned source tarball is the result of applying any patches and
12673 code snippets specified in the package @code{origin} (@pxref{Defining
12676 @cindex source, verification
12677 As with other derivations, the result of building a source derivation
12678 can be verified using the @option{--check} option (@pxref{build-check}).
12679 This is useful to validate that a (potentially already built or
12680 substituted, thus cached) package source matches against its declared
12683 Note that @command{guix build -S} compiles the sources only of the
12684 specified packages. They do not include the sources of statically
12685 linked dependencies and by themselves are insufficient for reproducing
12689 Fetch and return the source of @var{package-or-derivation} and all their
12690 dependencies, recursively. This is a handy way to obtain a local copy
12691 of all the source code needed to build @var{packages}, allowing you to
12692 eventually build them even without network access. It is an extension
12693 of the @option{--source} option and can accept one of the following
12694 optional argument values:
12698 This value causes the @option{--sources} option to behave in the same way
12699 as the @option{--source} option.
12702 Build the source derivations of all packages, including any source that
12703 might be listed as @code{inputs}. This is the default value.
12706 $ guix build --sources tzdata
12707 The following derivations will be built:
12708 /gnu/store/@dots{}-tzdata2015b.tar.gz.drv
12709 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
12713 Build the source derivations of all packages, as well of all transitive
12714 inputs to the packages. This can be used e.g.@: to
12715 prefetch package source for later offline building.
12718 $ guix build --sources=transitive tzdata
12719 The following derivations will be built:
12720 /gnu/store/@dots{}-tzcode2015b.tar.gz.drv
12721 /gnu/store/@dots{}-findutils-4.4.2.tar.xz.drv
12722 /gnu/store/@dots{}-grep-2.21.tar.xz.drv
12723 /gnu/store/@dots{}-coreutils-8.23.tar.xz.drv
12724 /gnu/store/@dots{}-make-4.1.tar.xz.drv
12725 /gnu/store/@dots{}-bash-4.3.tar.xz.drv
12731 @item --system=@var{system}
12732 @itemx -s @var{system}
12733 Attempt to build for @var{system}---e.g., @code{i686-linux}---instead of
12734 the system type of the build host. The @command{guix build} command allows
12735 you to repeat this option several times, in which case it builds for all the
12736 specified systems; other commands ignore extraneous @option{-s} options.
12739 The @option{--system} flag is for @emph{native} compilation and must not
12740 be confused with cross-compilation. See @option{--target} below for
12741 information on cross-compilation.
12744 An example use of this is on Linux-based systems, which can emulate
12745 different personalities. For instance, passing
12746 @option{--system=i686-linux} on an @code{x86_64-linux} system or
12747 @option{--system=armhf-linux} on an @code{aarch64-linux} system allows
12748 you to build packages in a complete 32-bit environment.
12751 Building for an @code{armhf-linux} system is unconditionally enabled on
12752 @code{aarch64-linux} machines, although certain aarch64 chipsets do not
12753 allow for this functionality, notably the ThunderX.
12756 Similarly, when transparent emulation with QEMU and @code{binfmt_misc}
12757 is enabled (@pxref{Virtualization Services,
12758 @code{qemu-binfmt-service-type}}), you can build for any system for
12759 which a QEMU @code{binfmt_misc} handler is installed.
12761 Builds for a system other than that of the machine you are using can
12762 also be offloaded to a remote machine of the right architecture.
12763 @xref{Daemon Offload Setup}, for more information on offloading.
12765 @item --target=@var{triplet}
12766 @cindex cross-compilation
12767 Cross-build for @var{triplet}, which must be a valid GNU triplet, such
12768 as @code{"aarch64-linux-gnu"} (@pxref{Specifying Target Triplets, GNU
12769 configuration triplets,, autoconf, Autoconf}).
12771 @item --list-systems
12772 List all the supported systems, that can be passed as an argument to
12775 @item --list-targets
12776 List all the supported targets, that can be passed as an argument to
12779 @anchor{build-check}
12781 @cindex determinism, checking
12782 @cindex reproducibility, checking
12783 Rebuild @var{package-or-derivation}, which are already available in the
12784 store, and raise an error if the build results are not bit-for-bit
12787 This mechanism allows you to check whether previously installed
12788 substitutes are genuine (@pxref{Substitutes}), or whether the build result
12789 of a package is deterministic. @xref{Invoking guix challenge}, for more
12790 background information and tools.
12792 When used in conjunction with @option{--keep-failed}, the differing
12793 output is kept in the store, under @file{/gnu/store/@dots{}-check}.
12794 This makes it easy to look for differences between the two results.
12797 @cindex repairing store items
12798 @cindex corruption, recovering from
12799 Attempt to repair the specified store items, if they are corrupt, by
12800 re-downloading or rebuilding them.
12802 This operation is not atomic and thus restricted to @code{root}.
12804 @item --derivations
12806 Return the derivation paths, not the output paths, of the given
12809 @item --root=@var{file}
12810 @itemx -r @var{file}
12811 @cindex GC roots, adding
12812 @cindex garbage collector roots, adding
12813 Make @var{file} a symlink to the result, and register it as a garbage
12816 Consequently, the results of this @command{guix build} invocation are
12817 protected from garbage collection until @var{file} is removed. When
12818 that option is omitted, build results are eligible for garbage
12819 collection as soon as the build completes. @xref{Invoking guix gc}, for
12823 @cindex build logs, access
12824 Return the build log file names or URLs for the given
12825 @var{package-or-derivation}, or raise an error if build logs are
12828 This works regardless of how packages or derivations are specified. For
12829 instance, the following invocations are equivalent:
12832 guix build --log-file $(guix build -d guile)
12833 guix build --log-file $(guix build guile)
12834 guix build --log-file guile
12835 guix build --log-file -e '(@@ (gnu packages guile) guile-2.0)'
12838 If a log is unavailable locally, and unless @option{--no-substitutes} is
12839 passed, the command looks for a corresponding log on one of the
12840 substitute servers (as specified with @option{--substitute-urls}).
12842 So for instance, imagine you want to see the build log of GDB on
12843 @code{aarch64}, but you are actually on an @code{x86_64} machine:
12846 $ guix build --log-file gdb -s aarch64-linux
12847 https://@value{SUBSTITUTE-SERVER-1}/log/@dots{}-gdb-7.10
12850 You can freely access a huge library of build logs!
12853 @node Debugging Build Failures
12854 @subsection Debugging Build Failures
12856 @cindex build failures, debugging
12857 When defining a new package (@pxref{Defining Packages}), you will
12858 probably find yourself spending some time debugging and tweaking the
12859 build until it succeeds. To do that, you need to operate the build
12860 commands yourself in an environment as close as possible to the one the
12863 To that end, the first thing to do is to use the @option{--keep-failed}
12864 or @option{-K} option of @command{guix build}, which will keep the
12865 failed build tree in @file{/tmp} or whatever directory you specified as
12866 @env{TMPDIR} (@pxref{Common Build Options, @option{--keep-failed}}).
12868 From there on, you can @command{cd} to the failed build tree and source
12869 the @file{environment-variables} file, which contains all the
12870 environment variable definitions that were in place when the build
12871 failed. So let's say you're debugging a build failure in package
12872 @code{foo}; a typical session would look like this:
12875 $ guix build foo -K
12876 @dots{} @i{build fails}
12877 $ cd /tmp/guix-build-foo.drv-0
12878 $ source ./environment-variables
12882 Now, you can invoke commands as if you were the daemon (almost) and
12883 troubleshoot your build process.
12885 Sometimes it happens that, for example, a package's tests pass when you
12886 run them manually but they fail when the daemon runs them. This can
12887 happen because the daemon runs builds in containers where, unlike in our
12888 environment above, network access is missing, @file{/bin/sh} does not
12889 exist, etc. (@pxref{Build Environment Setup}).
12891 In such cases, you may need to run inspect the build process from within
12892 a container similar to the one the build daemon creates:
12895 $ guix build -K foo
12897 $ cd /tmp/guix-build-foo.drv-0
12898 $ guix shell --no-grafts -C -D foo strace gdb
12899 [env]# source ./environment-variables
12903 Here, @command{guix shell -C} creates a container and spawns a new
12904 shell in it (@pxref{Invoking guix shell}). The @command{strace gdb}
12905 part adds the @command{strace} and @command{gdb} commands to
12906 the container, which you may find handy while debugging. The
12907 @option{--no-grafts} option makes sure we get the exact same
12908 environment, with ungrafted packages (@pxref{Security Updates}, for more
12911 To get closer to a container like that used by the build daemon, we can
12912 remove @file{/bin/sh}:
12918 (Don't worry, this is harmless: this is all happening in the throw-away
12919 container created by @command{guix shell}.)
12921 The @command{strace} command is probably not in the search path, but we
12925 [env]# $GUIX_ENVIRONMENT/bin/strace -f -o log make check
12928 In this way, not only you will have reproduced the environment variables
12929 the daemon uses, you will also be running the build process in a container
12930 similar to the one the daemon uses.
12933 @node Invoking guix edit
12934 @section Invoking @command{guix edit}
12936 @cindex @command{guix edit}
12937 @cindex package definition, editing
12938 So many packages, so many source files! The @command{guix edit} command
12939 facilitates the life of users and packagers by pointing their editor at
12940 the source file containing the definition of the specified packages.
12944 guix edit gcc@@4.9 vim
12948 launches the program specified in the @env{VISUAL} or in the
12949 @env{EDITOR} environment variable to view the recipe of GCC@tie{}4.9.3
12952 If you are using a Guix Git checkout (@pxref{Building from Git}), or
12953 have created your own packages on @env{GUIX_PACKAGE_PATH}
12954 (@pxref{Package Modules}), you will be able to edit the package
12955 recipes. In other cases, you will be able to examine the read-only recipes
12956 for packages currently in the store.
12958 Instead of @env{GUIX_PACKAGE_PATH}, the command-line option
12959 @option{--load-path=@var{directory}} (or in short @option{-L
12960 @var{directory}}) allows you to add @var{directory} to the front of the
12961 package module search path and so make your own packages visible.
12963 @node Invoking guix download
12964 @section Invoking @command{guix download}
12966 @cindex @command{guix download}
12967 @cindex downloading package sources
12968 When writing a package definition, developers typically need to download
12969 a source tarball, compute its SHA256 hash, and write that
12970 hash in the package definition (@pxref{Defining Packages}). The
12971 @command{guix download} tool helps with this task: it downloads a file
12972 from the given URI, adds it to the store, and prints both its file name
12973 in the store and its SHA256 hash.
12975 The fact that the downloaded file is added to the store saves bandwidth:
12976 when the developer eventually tries to build the newly defined package
12977 with @command{guix build}, the source tarball will not have to be
12978 downloaded again because it is already in the store. It is also a
12979 convenient way to temporarily stash files, which may be deleted
12980 eventually (@pxref{Invoking guix gc}).
12982 The @command{guix download} command supports the same URIs as used in
12983 package definitions. In particular, it supports @code{mirror://} URIs.
12984 @code{https} URIs (HTTP over TLS) are supported @emph{provided} the
12985 Guile bindings for GnuTLS are available in the user's environment; when
12986 they are not available, an error is raised. @xref{Guile Preparations,
12987 how to install the GnuTLS bindings for Guile,, gnutls-guile,
12988 GnuTLS-Guile}, for more information.
12990 @command{guix download} verifies HTTPS server certificates by loading
12991 the certificates of X.509 authorities from the directory pointed to by
12992 the @env{SSL_CERT_DIR} environment variable (@pxref{X.509
12993 Certificates}), unless @option{--no-check-certificate} is used.
12995 The following options are available:
12998 @item --hash=@var{algorithm}
12999 @itemx -H @var{algorithm}
13000 Compute a hash using the specified @var{algorithm}. @xref{Invoking guix
13001 hash}, for more information.
13003 @item --format=@var{fmt}
13004 @itemx -f @var{fmt}
13005 Write the hash in the format specified by @var{fmt}. For more
13006 information on the valid values for @var{fmt}, @pxref{Invoking guix hash}.
13008 @item --no-check-certificate
13009 Do not validate the X.509 certificates of HTTPS servers.
13011 When using this option, you have @emph{absolutely no guarantee} that you
13012 are communicating with the authentic server responsible for the given
13013 URL, which makes you vulnerable to ``man-in-the-middle'' attacks.
13015 @item --output=@var{file}
13016 @itemx -o @var{file}
13017 Save the downloaded file to @var{file} instead of adding it to the
13021 @node Invoking guix hash
13022 @section Invoking @command{guix hash}
13024 @cindex @command{guix hash}
13025 The @command{guix hash} command computes the hash of a file.
13026 It is primarily a convenience tool for anyone contributing to the
13027 distribution: it computes the cryptographic hash of one or more files, which can be
13028 used in the definition of a package (@pxref{Defining Packages}).
13030 The general syntax is:
13033 guix hash @var{option} @var{file} ...
13036 When @var{file} is @code{-} (a hyphen), @command{guix hash} computes the
13037 hash of data read from standard input. @command{guix hash} has the
13042 @item --hash=@var{algorithm}
13043 @itemx -H @var{algorithm}
13044 Compute a hash using the specified @var{algorithm}, @code{sha256} by
13047 @var{algorithm} must be the name of a cryptographic hash algorithm
13048 supported by Libgcrypt @i{via} Guile-Gcrypt---e.g., @code{sha512} or
13049 @code{sha3-256} (@pxref{Hash Functions,,, guile-gcrypt, Guile-Gcrypt
13050 Reference Manual}).
13052 @item --format=@var{fmt}
13053 @itemx -f @var{fmt}
13054 Write the hash in the format specified by @var{fmt}.
13056 Supported formats: @code{base64}, @code{nix-base32}, @code{base32}, @code{base16}
13057 (@code{hex} and @code{hexadecimal} can be used as well).
13059 If the @option{--format} option is not specified, @command{guix hash}
13060 will output the hash in @code{nix-base32}. This representation is used
13061 in the definitions of packages.
13065 The @option{--recursive} option is deprecated in favor of
13066 @option{--serializer=nar} (see below); @option{-r} remains accepted as a
13067 convenient shorthand.
13069 @item --serializer=@var{type}
13070 @itemx -S @var{type}
13071 Compute the hash on @var{file} using @var{type} serialization.
13073 @var{type} may be one of the following:
13077 This is the default: it computes the hash of a file's contents.
13080 Compute the hash of a ``normalized archive'' (or ``nar'') containing
13081 @var{file}, including its children if it is a directory. Some of the
13082 metadata of @var{file} is part of the archive; for instance, when
13083 @var{file} is a regular file, the hash is different depending on whether
13084 @var{file} is executable or not. Metadata such as time stamps have no
13085 impact on the hash (@pxref{Invoking guix archive}, for more info on the
13087 @c FIXME: Replace xref above with xref to an ``Archive'' section when
13091 Compute the hash of the file or directory as a Git ``tree'', following
13092 the same method as the Git version control system.
13095 @item --exclude-vcs
13097 When combined with @option{--recursive}, exclude version control system
13098 directories (@file{.bzr}, @file{.git}, @file{.hg}, etc.).
13101 As an example, here is how you would compute the hash of a Git checkout,
13102 which is useful when using the @code{git-fetch} method (@pxref{origin
13106 $ git clone http://example.org/foo.git
13108 $ guix hash -x --serializer=nar .
13112 @node Invoking guix import
13113 @section Invoking @command{guix import}
13115 @cindex importing packages
13116 @cindex package import
13117 @cindex package conversion
13118 @cindex Invoking @command{guix import}
13119 The @command{guix import} command is useful for people who would like to
13120 add a package to the distribution with as little work as
13121 possible---a legitimate demand. The command knows of a few
13122 repositories from which it can ``import'' package metadata. The result
13123 is a package definition, or a template thereof, in the format we know
13124 (@pxref{Defining Packages}).
13126 The general syntax is:
13129 guix import @var{importer} @var{options}@dots{}
13132 @var{importer} specifies the source from which to import package
13133 metadata, and @var{options} specifies a package identifier and other
13134 options specific to @var{importer}.
13136 Some of the importers rely on the ability to run the @command{gpgv} command.
13137 For these, GnuPG must be installed and in @code{$PATH}; run @code{guix install
13140 Currently, the available ``importers'' are:
13144 Import metadata for the given GNU package. This provides a template
13145 for the latest version of that GNU package, including the hash of its
13146 source tarball, and its canonical synopsis and description.
13148 Additional information such as the package dependencies and its
13149 license needs to be figured out manually.
13151 For example, the following command returns a package definition for
13155 guix import gnu hello
13158 Specific command-line options are:
13161 @item --key-download=@var{policy}
13162 As for @command{guix refresh}, specify the policy to handle missing
13163 OpenPGP keys when verifying the package signature. @xref{Invoking guix
13164 refresh, @option{--key-download}}.
13169 Import metadata from the @uref{https://pypi.python.org/, Python Package
13170 Index}. Information is taken from the JSON-formatted description
13171 available at @code{pypi.python.org} and usually includes all the relevant
13172 information, including package dependencies. For maximum efficiency, it
13173 is recommended to install the @command{unzip} utility, so that the
13174 importer can unzip Python wheels and gather data from them.
13176 The command below imports metadata for the latest version of the
13177 @code{itsdangerous} Python package:
13180 guix import pypi itsdangerous
13183 You can also ask for a specific version:
13186 guix import pypi itsdangerous@@1.1.0
13192 Traverse the dependency graph of the given upstream package recursively
13193 and generate package expressions for all those packages that are not yet
13199 Import metadata from @uref{https://rubygems.org/, RubyGems}. Information
13200 is taken from the JSON-formatted description available at
13201 @code{rubygems.org} and includes most relevant information, including
13202 runtime dependencies. There are some caveats, however. The metadata
13203 doesn't distinguish between synopses and descriptions, so the same string
13204 is used for both fields. Additionally, the details of non-Ruby
13205 dependencies required to build native extensions is unavailable and left
13206 as an exercise to the packager.
13208 The command below imports metadata for the @code{rails} Ruby package:
13211 guix import gem rails
13217 Traverse the dependency graph of the given upstream package recursively
13218 and generate package expressions for all those packages that are not yet
13225 Import metadata from @uref{https://content.minetest.net, ContentDB}.
13226 Information is taken from the JSON-formatted metadata provided through
13227 @uref{https://content.minetest.net/help/api/, ContentDB's API} and
13228 includes most relevant information, including dependencies. There are
13229 some caveats, however. The license information is often incomplete.
13230 The commit hash is sometimes missing. The descriptions are in the
13231 Markdown format, but Guix uses Texinfo instead. Texture packs and
13232 subgames are unsupported.
13234 The command below imports metadata for the Mesecons mod by Jeija:
13237 guix import minetest Jeija/mesecons
13240 The author name can also be left out:
13243 guix import minetest mesecons
13249 Traverse the dependency graph of the given upstream package recursively
13250 and generate package expressions for all those packages that are not yet
13256 Import metadata from @uref{https://www.metacpan.org/, MetaCPAN}.
13257 Information is taken from the JSON-formatted metadata provided through
13258 @uref{https://fastapi.metacpan.org/, MetaCPAN's API} and includes most
13259 relevant information, such as module dependencies. License information
13260 should be checked closely. If Perl is available in the store, then the
13261 @code{corelist} utility will be used to filter core modules out of the
13262 list of dependencies.
13264 The command command below imports metadata for the Acme::Boolean Perl
13268 guix import cpan Acme::Boolean
13273 @cindex Bioconductor
13274 Import metadata from @uref{https://cran.r-project.org/, CRAN}, the
13275 central repository for the @uref{https://r-project.org, GNU@tie{}R
13276 statistical and graphical environment}.
13278 Information is extracted from the @file{DESCRIPTION} file of the package.
13280 The command command below imports metadata for the Cairo R package:
13283 guix import cran Cairo
13286 You can also ask for a specific version:
13289 guix import cran rasterVis@@0.50.3
13292 When @option{--recursive} is added, the importer will traverse the
13293 dependency graph of the given upstream package recursively and generate
13294 package expressions for all those packages that are not yet in Guix.
13296 When @option{--style=specification} is added, the importer will generate
13297 package definitions whose inputs are package specifications instead of
13298 references to package variables. This is useful when generated package
13299 definitions are to be appended to existing user modules, as the list of
13300 used package modules need not be changed. The default is
13301 @option{--style=variable}.
13303 When @option{--archive=bioconductor} is added, metadata is imported from
13304 @uref{https://www.bioconductor.org/, Bioconductor}, a repository of R
13305 packages for the analysis and comprehension of high-throughput
13306 genomic data in bioinformatics.
13308 Information is extracted from the @file{DESCRIPTION} file contained in the
13311 The command below imports metadata for the GenomicRanges R package:
13314 guix import cran --archive=bioconductor GenomicRanges
13317 Finally, you can also import R packages that have not yet been published on
13318 CRAN or Bioconductor as long as they are in a git repository. Use
13319 @option{--archive=git} followed by the URL of the git repository:
13322 guix import cran --archive=git https://github.com/immunogenomics/harmony
13328 Import TeX package information from the TeX Live package database for
13329 TeX packages that are part of the @uref{https://www.tug.org/texlive/,
13330 TeX Live distribution}.
13332 Information about the package is obtained from the TeX Live package
13333 database, a plain text file that is included in the @code{texlive-bin}
13334 package. The source code is downloaded from possibly multiple locations
13335 in the SVN repository of the Tex Live project.
13337 The command command below imports metadata for the @code{fontspec}
13341 guix import texlive fontspec
13345 @cindex JSON, import
13346 Import package metadata from a local JSON file. Consider the following
13347 example package definition in JSON format:
13353 "source": "mirror://gnu/hello/hello-2.10.tar.gz",
13354 "build-system": "gnu",
13355 "home-page": "https://www.gnu.org/software/hello/",
13356 "synopsis": "Hello, GNU world: An example GNU package",
13357 "description": "GNU Hello prints a greeting.",
13358 "license": "GPL-3.0+",
13359 "native-inputs": ["gettext"]
13363 The field names are the same as for the @code{<package>} record
13364 (@xref{Defining Packages}). References to other packages are provided
13365 as JSON lists of quoted package specification strings such as
13366 @code{guile} or @code{guile@@2.0}.
13368 The importer also supports a more explicit source definition using the
13369 common fields for @code{<origin>} records:
13375 "method": "url-fetch",
13376 "uri": "mirror://gnu/hello/hello-2.10.tar.gz",
13378 "base32": "0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i"
13385 The command below reads metadata from the JSON file @code{hello.json}
13386 and outputs a package expression:
13389 guix import json hello.json
13394 Import metadata from the Haskell community's central package archive
13395 @uref{https://hackage.haskell.org/, Hackage}. Information is taken from
13396 Cabal files and includes all the relevant information, including package
13399 Specific command-line options are:
13404 Read a Cabal file from standard input.
13405 @item --no-test-dependencies
13407 Do not include dependencies required only by the test suites.
13408 @item --cabal-environment=@var{alist}
13409 @itemx -e @var{alist}
13410 @var{alist} is a Scheme alist defining the environment in which the
13411 Cabal conditionals are evaluated. The accepted keys are: @code{os},
13412 @code{arch}, @code{impl} and a string representing the name of a flag.
13413 The value associated with a flag has to be either the symbol
13414 @code{true} or @code{false}. The value associated with other keys
13415 has to conform to the Cabal file format definition. The default value
13416 associated with the keys @code{os}, @code{arch} and @code{impl} is
13417 @samp{linux}, @samp{x86_64} and @samp{ghc}, respectively.
13420 Traverse the dependency graph of the given upstream package recursively
13421 and generate package expressions for all those packages that are not yet
13425 The command below imports metadata for the latest version of the
13426 HTTP Haskell package without including test dependencies and
13427 specifying the value of the flag @samp{network-uri} as @code{false}:
13430 guix import hackage -t -e "'((\"network-uri\" . false))" HTTP
13433 A specific package version may optionally be specified by following the
13434 package name by an at-sign and a version number as in the following example:
13437 guix import hackage mtl@@2.1.3.1
13442 The @code{stackage} importer is a wrapper around the @code{hackage} one.
13443 It takes a package name, looks up the package version included in a
13444 long-term support (LTS) @uref{https://www.stackage.org, Stackage}
13445 release and uses the @code{hackage} importer to retrieve its metadata.
13446 Note that it is up to you to select an LTS release compatible with the
13447 GHC compiler used by Guix.
13449 Specific command-line options are:
13452 @item --no-test-dependencies
13454 Do not include dependencies required only by the test suites.
13455 @item --lts-version=@var{version}
13456 @itemx -l @var{version}
13457 @var{version} is the desired LTS release version. If omitted the latest
13461 Traverse the dependency graph of the given upstream package recursively
13462 and generate package expressions for all those packages that are not yet
13466 The command below imports metadata for the HTTP Haskell package
13467 included in the LTS Stackage release version 7.18:
13470 guix import stackage --lts-version=7.18 HTTP
13475 Import metadata from an Emacs Lisp Package Archive (ELPA) package
13476 repository (@pxref{Packages,,, emacs, The GNU Emacs Manual}).
13478 Specific command-line options are:
13481 @item --archive=@var{repo}
13482 @itemx -a @var{repo}
13483 @var{repo} identifies the archive repository from which to retrieve the
13484 information. Currently the supported repositories and their identifiers
13488 @uref{https://elpa.gnu.org/packages, GNU}, selected by the @code{gnu}
13489 identifier. This is the default.
13491 Packages from @code{elpa.gnu.org} are signed with one of the keys
13492 contained in the GnuPG keyring at
13493 @file{share/emacs/25.1/etc/package-keyring.gpg} (or similar) in the
13494 @code{emacs} package (@pxref{Package Installation, ELPA package
13495 signatures,, emacs, The GNU Emacs Manual}).
13498 @uref{https://elpa.nongnu.org/nongnu/, NonGNU}, selected by the
13499 @code{nongnu} identifier.
13502 @uref{https://stable.melpa.org/packages, MELPA-Stable}, selected by the
13503 @code{melpa-stable} identifier.
13506 @uref{https://melpa.org/packages, MELPA}, selected by the @code{melpa}
13512 Traverse the dependency graph of the given upstream package recursively
13513 and generate package expressions for all those packages that are not yet
13519 Import metadata from the crates.io Rust package repository
13520 @uref{https://crates.io, crates.io}, as in this example:
13523 guix import crate blake2-rfc
13526 The crate importer also allows you to specify a version string:
13529 guix import crate constant-time-eq@@0.1.0
13532 Additional options include:
13537 Traverse the dependency graph of the given upstream package recursively
13538 and generate package expressions for all those packages that are not yet
13544 Import metadata from the Elm package repository
13545 @uref{https://package.elm-lang.org, package.elm-lang.org}, as in this example:
13548 guix import elm elm-explorations/webgl
13551 The Elm importer also allows you to specify a version string:
13554 guix import elm elm-explorations/webgl@@1.1.3
13557 Additional options include:
13562 Traverse the dependency graph of the given upstream package recursively
13563 and generate package expressions for all those packages that are not yet
13570 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
13571 repository used by the OCaml community.
13573 Additional options include:
13578 Traverse the dependency graph of the given upstream package recursively
13579 and generate package expressions for all those packages that are not yet
13582 By default, packages are searched in the official OPAM repository. This
13583 option, which can be used more than once, lets you add other repositories
13584 which will be searched for packages. It accepts as valid arguments:
13587 @item the name of a known repository - can be one of @code{opam},
13588 @code{coq} (equivalent to @code{coq-released}),
13589 @code{coq-core-dev}, @code{coq-extra-dev} or @code{grew}.
13590 @item the URL of a repository as expected by the
13591 @code{opam repository add} command (for instance, the URL equivalent
13592 of the above @code{opam} name would be
13593 @uref{https://opam.ocaml.org}).
13594 @item the path to a local copy of a repository (a directory containing a
13595 @file{packages/} sub-directory).
13598 Repositories are assumed to be passed to this option by order of
13599 preference. The additional repositories will not replace the default
13600 @code{opam} repository, which is always kept as a fallback.
13602 Also, please note that versions are not compared across repositories.
13603 The first repository (from left to right) that has at least one version
13604 of a given package will prevail over any others, and the version
13605 imported will be the latest one found @emph{in this repository only}.
13611 Import metadata for a Go module using
13612 @uref{https://proxy.golang.org, proxy.golang.org}.
13615 guix import go gopkg.in/yaml.v2
13618 It is possible to use a package specification with a @code{@@VERSION}
13619 suffix to import a specific version.
13621 Additional options include:
13626 Traverse the dependency graph of the given upstream package recursively
13627 and generate package expressions for all those packages that are not yet
13629 @item --pin-versions
13630 When using this option, the importer preserves the exact versions of the
13631 Go modules dependencies instead of using their latest available
13632 versions. This can be useful when attempting to import packages that
13633 recursively depend on former versions of themselves to build. When
13634 using this mode, the symbol of the package is made by appending the
13635 version to its name, so that multiple versions of the same package can
13641 Import metadata for @uref{https://wiki.call-cc.org/eggs, CHICKEN eggs}.
13642 The information is taken from @file{PACKAGE.egg} files found in the
13643 @uref{git://code.call-cc.org/eggs-5-all, eggs-5-all} Git
13644 repository. However, it does not provide all the information that we
13645 need, there is no ``description'' field, and the licenses used are not
13646 always precise (BSD is often used instead of BSD-N).
13649 guix import egg sourcehut
13652 You can also ask for a specific version:
13655 guix import egg arrays@@1.0
13658 Additional options include:
13662 Traverse the dependency graph of the given upstream package recursively
13663 and generate package expressions for all those packages that are not yet
13669 Import metadata from the hex.pm Erlang and Elixir package repository
13670 @uref{https://hex.pm, hex.pm}, as in this example:
13673 guix import hexpm stun
13676 The importer tries to determine the build system used by the package.
13678 The hexpm importer also allows you to specify a version string:
13681 guix import hexpm cf@@0.3.0
13684 Additional options include:
13689 Traverse the dependency graph of the given upstream package recursively
13690 and generate package expressions for all those packages that are not yet
13695 The structure of the @command{guix import} code is modular. It would be
13696 useful to have more importers for other package formats, and your help
13697 is welcome here (@pxref{Contributing}).
13699 @node Invoking guix refresh
13700 @section Invoking @command{guix refresh}
13702 @cindex @command {guix refresh}
13703 The primary audience of the @command{guix refresh} command is packagers.
13704 As a user, you may be interested in the @option{--with-latest} option,
13705 which can bring you package update superpowers built upon @command{guix
13706 refresh} (@pxref{Package Transformation Options,
13707 @option{--with-latest}}). By default, @command{guix refresh} reports
13708 any packages provided by the distribution that are outdated compared to
13709 the latest upstream version, like this:
13713 gnu/packages/gettext.scm:29:13: gettext would be upgraded from 0.18.1.1 to 0.18.2.1
13714 gnu/packages/glib.scm:77:12: glib would be upgraded from 2.34.3 to 2.37.0
13717 Alternatively, one can specify packages to consider, in which case a
13718 warning is emitted for packages that lack an updater:
13721 $ guix refresh coreutils guile guile-ssh
13722 gnu/packages/ssh.scm:205:2: warning: no updater for guile-ssh
13723 gnu/packages/guile.scm:136:12: guile would be upgraded from 2.0.12 to 2.0.13
13726 @command{guix refresh} browses the upstream repository of each package and determines
13727 the highest version number of the releases therein. The command
13728 knows how to update specific types of packages: GNU packages, ELPA
13729 packages, etc.---see the documentation for @option{--type} below. There
13730 are many packages, though, for which it lacks a method to determine
13731 whether a new upstream release is available. However, the mechanism is
13732 extensible, so feel free to get in touch with us to add a new method!
13737 Consider the packages specified, and all the packages upon which they depend.
13740 $ guix refresh --recursive coreutils
13741 gnu/packages/acl.scm:40:13: acl would be upgraded from 2.2.53 to 2.3.1
13742 gnu/packages/m4.scm:30:12: 1.4.18 is already the latest version of m4
13743 gnu/packages/xml.scm:68:2: warning: no updater for expat
13744 gnu/packages/multiprecision.scm:40:12: 6.1.2 is already the latest version of gmp
13750 Sometimes the upstream name differs from the package name used in Guix,
13751 and @command{guix refresh} needs a little help. Most updaters honor the
13752 @code{upstream-name} property in package definitions, which can be used
13756 (define-public network-manager
13758 (name "network-manager")
13760 (properties '((upstream-name . "NetworkManager")))))
13763 When passed @option{--update}, it modifies distribution source files to
13764 update the version numbers and source tarball hashes of those package
13765 recipes (@pxref{Defining Packages}). This is achieved by downloading
13766 each package's latest source tarball and its associated OpenPGP
13767 signature, authenticating the downloaded tarball against its signature
13768 using @command{gpgv}, and finally computing its hash---note that GnuPG must be
13769 installed and in @code{$PATH}; run @code{guix install gnupg} if needed.
13772 key used to sign the tarball is missing from the user's keyring, an
13773 attempt is made to automatically retrieve it from a public key server;
13774 when this is successful, the key is added to the user's keyring; otherwise,
13775 @command{guix refresh} reports an error.
13777 The following options are supported:
13781 @item --expression=@var{expr}
13782 @itemx -e @var{expr}
13783 Consider the package @var{expr} evaluates to.
13785 This is useful to precisely refer to a package, as in this example:
13788 guix refresh -l -e '(@@@@ (gnu packages commencement) glibc-final)'
13791 This command lists the dependents of the ``final'' libc (essentially all
13796 Update distribution source files (package recipes) in place. This is
13797 usually run from a checkout of the Guix source tree (@pxref{Running
13798 Guix Before It Is Installed}):
13801 $ ./pre-inst-env guix refresh -s non-core -u
13804 @xref{Defining Packages}, for more information on package definitions.
13806 @item --select=[@var{subset}]
13807 @itemx -s @var{subset}
13808 Select all the packages in @var{subset}, one of @code{core} or
13811 The @code{core} subset refers to all the packages at the core of the
13812 distribution---i.e., packages that are used to build ``everything
13813 else''. This includes GCC, libc, Binutils, Bash, etc. Usually,
13814 changing one of these packages in the distribution entails a rebuild of
13815 all the others. Thus, such updates are an inconvenience to users in
13816 terms of build time or bandwidth used to achieve the upgrade.
13818 The @code{non-core} subset refers to the remaining packages. It is
13819 typically useful in cases where an update of the core packages would be
13822 @item --manifest=@var{file}
13823 @itemx -m @var{file}
13824 Select all the packages from the manifest in @var{file}. This is useful to
13825 check if any packages of the user manifest can be updated.
13827 @item --type=@var{updater}
13828 @itemx -t @var{updater}
13829 Select only packages handled by @var{updater} (may be a comma-separated
13830 list of updaters). Currently, @var{updater} may be one of:
13834 the updater for GNU packages;
13836 the updater for packages hosted at @uref{https://savannah.gnu.org, Savannah};
13838 the updater for packages hosted at @uref{https://sourceforge.net, SourceForge};
13840 the updater for GNOME packages;
13842 the updater for KDE packages;
13844 the updater for X.org packages;
13846 the updater for packages hosted on kernel.org;
13848 the updater for @uref{https://wiki.call-cc.org/eggs/, Egg} packages;
13850 the updater for @uref{https://elpa.gnu.org/, ELPA} packages;
13852 the updater for @uref{https://cran.r-project.org/, CRAN} packages;
13854 the updater for @uref{https://www.bioconductor.org/, Bioconductor} R packages;
13856 the updater for @uref{https://www.cpan.org/, CPAN} packages;
13858 the updater for @uref{https://pypi.python.org, PyPI} packages.
13860 the updater for @uref{https://rubygems.org, RubyGems} packages.
13862 the updater for @uref{https://github.com, GitHub} packages.
13864 the updater for @uref{https://hackage.haskell.org, Hackage} packages.
13866 the updater for @uref{https://www.stackage.org, Stackage} packages.
13868 the updater for @uref{https://crates.io, Crates} packages.
13870 the updater for @uref{https://launchpad.net, Launchpad} packages.
13872 a generic updater that crawls the HTML page where the source tarball of
13873 the package is hosted, when applicable.
13876 a generic updater for packages hosted on Git repositories. It tries to
13877 be smart about parsing Git tag names, but if it is not able to parse the
13878 tag name and compare tags correctly, users can define the following
13879 properties for a package.
13882 @item @code{release-tag-prefix}: a regular expression for matching a prefix of
13885 @item @code{release-tag-suffix}: a regular expression for matching a suffix of
13888 @item @code{release-tag-version-delimiter}: a string used as the delimiter in
13889 the tag name for separating the numbers of the version.
13891 @item @code{accept-pre-releases}: by default, the updater will ignore
13892 pre-releases; to make it also look for pre-releases, set the this
13893 property to @code{#t}.
13902 '((release-tag-prefix . "^release0-")
13903 (release-tag-suffix . "[a-z]?$")
13904 (release-tag-version-delimiter . ":"))))
13910 For instance, the following command only checks for updates of Emacs
13911 packages hosted at @code{elpa.gnu.org} and for updates of CRAN packages:
13914 $ guix refresh --type=elpa,cran
13915 gnu/packages/statistics.scm:819:13: r-testthat would be upgraded from 0.10.0 to 0.11.0
13916 gnu/packages/emacs.scm:856:13: emacs-auctex would be upgraded from 11.88.6 to 11.88.9
13919 @item --list-updaters
13920 List available updaters and exit (see @option{--type} above).
13922 For each updater, display the fraction of packages it covers; at the
13923 end, display the fraction of packages covered by all these updaters.
13926 In addition, @command{guix refresh} can be passed one or more package
13927 names, as in this example:
13930 $ ./pre-inst-env guix refresh -u emacs idutils gcc@@4.8
13934 The command above specifically updates the @code{emacs} and
13935 @code{idutils} packages. The @option{--select} option would have no
13936 effect in this case. You might also want to update definitions that
13937 correspond to the packages installed in your profile:
13940 $ ./pre-inst-env guix refresh -u \
13941 $(guix package --list-installed | cut -f1)
13944 When considering whether to upgrade a package, it is sometimes
13945 convenient to know which packages would be affected by the upgrade and
13946 should be checked for compatibility. For this the following option may
13947 be used when passing @command{guix refresh} one or more package names:
13951 @item --list-dependent
13953 List top-level dependent packages that would need to be rebuilt as a
13954 result of upgrading one or more packages.
13956 @xref{Invoking guix graph, the @code{reverse-package} type of
13957 @command{guix graph}}, for information on how to visualize the list of
13958 dependents of a package.
13962 Be aware that the @option{--list-dependent} option only
13963 @emph{approximates} the rebuilds that would be required as a result of
13964 an upgrade. More rebuilds might be required under some circumstances.
13967 $ guix refresh --list-dependent flex
13968 Building the following 120 packages would ensure 213 dependent packages are rebuilt:
13969 hop@@2.4.0 emacs-geiser@@0.13 notmuch@@0.18 mu@@0.9.9.5 cflow@@1.4 idutils@@4.6 @dots{}
13972 The command above lists a set of packages that could be built to check
13973 for compatibility with an upgraded @code{flex} package.
13977 @item --list-transitive
13978 List all the packages which one or more packages depend upon.
13981 $ guix refresh --list-transitive flex
13982 flex@@2.6.4 depends on the following 25 packages: perl@@5.28.0 help2man@@1.47.6
13983 bison@@3.0.5 indent@@2.2.10 tar@@1.30 gzip@@1.9 bzip2@@1.0.6 xz@@5.2.4 file@@5.33 @dots{}
13988 The command above lists a set of packages which, when changed, would cause
13989 @code{flex} to be rebuilt.
13991 The following options can be used to customize GnuPG operation:
13995 @item --gpg=@var{command}
13996 Use @var{command} as the GnuPG 2.x command. @var{command} is searched
13997 for in @code{$PATH}.
13999 @item --keyring=@var{file}
14000 Use @var{file} as the keyring for upstream keys. @var{file} must be in the
14001 @dfn{keybox format}. Keybox files usually have a name ending in @file{.kbx}
14002 and the GNU@tie{}Privacy Guard (GPG) can manipulate these files
14003 (@pxref{kbxutil, @command{kbxutil},, gnupg, Using the GNU Privacy Guard}, for
14004 information on a tool to manipulate keybox files).
14006 When this option is omitted, @command{guix refresh} uses
14007 @file{~/.config/guix/upstream/trustedkeys.kbx} as the keyring for upstream
14008 signing keys. OpenPGP signatures are checked against keys from this keyring;
14009 missing keys are downloaded to this keyring as well (see
14010 @option{--key-download} below).
14012 You can export keys from your default GPG keyring into a keybox file using
14013 commands like this one:
14016 gpg --export rms@@gnu.org | kbxutil --import-openpgp >> mykeyring.kbx
14019 Likewise, you can fetch keys to a specific keybox file like this:
14022 gpg --no-default-keyring --keyring mykeyring.kbx \
14023 --recv-keys @value{OPENPGP-SIGNING-KEY-ID}
14026 @xref{GPG Configuration Options, @option{--keyring},, gnupg, Using the GNU
14027 Privacy Guard}, for more information on GPG's @option{--keyring} option.
14029 @item --key-download=@var{policy}
14030 Handle missing OpenPGP keys according to @var{policy}, which may be one
14035 Always download missing OpenPGP keys from the key server, and add them
14036 to the user's GnuPG keyring.
14039 Never try to download missing OpenPGP keys. Instead just bail out.
14042 When a package signed with an unknown OpenPGP key is encountered, ask
14043 the user whether to download it or not. This is the default behavior.
14046 @item --key-server=@var{host}
14047 Use @var{host} as the OpenPGP key server when importing a public key.
14049 @item --load-path=@var{directory}
14050 @itemx -L @var{directory}
14051 Add @var{directory} to the front of the package module search path
14052 (@pxref{Package Modules}).
14054 This allows users to define their own packages and make them visible to
14055 the command-line tools.
14059 The @code{github} updater uses the
14060 @uref{https://developer.github.com/v3/, GitHub API} to query for new
14061 releases. When used repeatedly e.g.@: when refreshing all packages,
14062 GitHub will eventually refuse to answer any further API requests. By
14063 default 60 API requests per hour are allowed, and a full refresh on all
14064 GitHub packages in Guix requires more than this. Authentication with
14065 GitHub through the use of an API token alleviates these limits. To use
14066 an API token, set the environment variable @env{GUIX_GITHUB_TOKEN} to a
14067 token procured from @uref{https://github.com/settings/tokens} or
14071 @node Invoking guix style
14072 @section Invoking @command{guix style}
14074 The @command{guix style} command helps users and packagers alike style
14075 their package definitions and configuration files according to the
14076 latest fashionable trends. It can either reformat whole files, with the
14077 @option{--whole-file} option, or apply specific @dfn{styling rules} to
14078 individual package definitions. The command currently provides the
14079 following styling rules:
14083 formatting package definitions according to the project's conventions
14084 (@pxref{Formatting Code});
14087 rewriting package inputs to the ``new style'', as explained below.
14090 The way package inputs are written is going through a transition
14091 (@pxref{package Reference}, for more on package inputs). Until version
14092 1.3.0, package inputs were written using the ``old style'', where each
14093 input was given an explicit label, most of the time the package name:
14098 ;; The "old style" (deprecated).
14099 (inputs `(("libunistring" ,libunistring)
14100 ("libffi" ,libffi))))
14103 Today, the old style is deprecated and the preferred style looks like
14109 ;; The "new style".
14110 (inputs (list libunistring libffi)))
14113 Likewise, uses of @code{alist-delete} and friends to manipulate inputs
14114 is now deprecated in favor of @code{modify-inputs} (@pxref{Defining
14115 Package Variants}, for more info on @code{modify-inputs}).
14117 In the vast majority of cases, this is a purely mechanical change on the
14118 surface syntax that does not even incur a package rebuild. Running
14119 @command{guix style -S inputs} can do that for you, whether you're working on
14120 packages in Guix proper or in an external channel.
14122 The general syntax is:
14125 guix style [@var{options}] @var{package}@dots{}
14128 This causes @command{guix style} to analyze and rewrite the definition
14129 of @var{package}@dots{} or, when @var{package} is omitted, of @emph{all}
14130 the packages. The @option{--styling} or @option{-S} option allows you
14131 to select the style rule, the default rule being @code{format}---see
14134 To reformat entire source files, the syntax is:
14137 guix style --whole-file @var{file}@dots{}
14140 The available options are listed below.
14145 Show source file locations that would be edited but do not modify them.
14149 Reformat the given files in their entirety. In that case, subsequent
14150 arguments are interpreted as file names (rather than package names), and
14151 the @option{--styling} option has no effect.
14153 As an example, here is how you might reformat your operating system
14154 configuration (you need write permissions for the file):
14157 guix style -f /etc/config.scm
14160 @item --styling=@var{rule}
14161 @itemx -S @var{rule}
14162 Apply @var{rule}, one of the following styling rules:
14166 Format the given package definition(s)---this is the default styling
14167 rule. For example, a packager running Guix on a checkout
14168 (@pxref{Running Guix Before It Is Installed}) might want to reformat the
14169 definition of the Coreutils package like so:
14172 ./pre-inst-env guix style coreutils
14176 Rewrite package inputs to the ``new style'', as described above. This
14177 is how you would rewrite inputs of package @code{whatnot} in your own
14181 guix style -L ~/my/channel -S inputs whatnot
14184 Rewriting is done in a conservative way: preserving comments and bailing
14185 out if it cannot make sense of the code that appears in an inputs field.
14186 The @option{--input-simplification} option described below provides
14187 fine-grain control over when inputs should be simplified.
14190 @item --list-stylings
14192 List and describe the available styling rules and exit.
14194 @item --load-path=@var{directory}
14195 @itemx -L @var{directory}
14196 Add @var{directory} to the front of the package module search path
14197 (@pxref{Package Modules}).
14199 @item --expression=@var{expr}
14200 @itemx -e @var{expr}
14201 Style the package @var{expr} evaluates to.
14203 For example, running:
14206 guix style -e '(@@ (gnu packages gcc) gcc-5)'
14209 styles the @code{gcc-5} package definition.
14211 @item --input-simplification=@var{policy}
14212 When using the @code{inputs} styling rule, with @samp{-S inputs}, this
14213 option specifies the package input simplification policy for cases where
14214 an input label does not match the corresponding package name.
14215 @var{policy} may be one of the following:
14219 Simplify inputs only when the change is ``silent'', meaning that the
14220 package does not need to be rebuilt (its derivation is unchanged).
14223 Simplify inputs only when that is ``safe'' to do: the package might need
14224 to be rebuilt, but the change is known to have no observable effect.
14227 Simplify inputs even when input labels do not match package names, and
14228 even if that might have an observable effect.
14231 The default is @code{silent}, meaning that input simplifications do not
14232 trigger any package rebuild.
14235 @node Invoking guix lint
14236 @section Invoking @command{guix lint}
14238 @cindex @command{guix lint}
14239 @cindex package, checking for errors
14240 The @command{guix lint} command is meant to help package developers avoid
14241 common errors and use a consistent style. It runs a number of checks on
14242 a given set of packages in order to find common mistakes in their
14243 definitions. Available @dfn{checkers} include (see
14244 @option{--list-checkers} for a complete list):
14249 Validate certain typographical and stylistic rules about package
14250 descriptions and synopses.
14252 @item inputs-should-be-native
14253 Identify inputs that should most likely be native inputs.
14259 @itemx source-file-name
14260 Probe @code{home-page} and @code{source} URLs and report those that are
14261 invalid. Suggest a @code{mirror://} URL when applicable. If the
14262 @code{source} URL redirects to a GitHub URL, recommend usage of the GitHub
14263 URL@. Check that the source file name is meaningful, e.g.@: is not just a
14264 version number or ``git-checkout'', without a declared @code{file-name}
14265 (@pxref{origin Reference}).
14267 @item source-unstable-tarball
14268 Parse the @code{source} URL to determine if a tarball from GitHub is
14269 autogenerated or if it is a release tarball. Unfortunately GitHub's
14270 autogenerated tarballs are sometimes regenerated.
14273 Check that the derivation of the given packages can be successfully
14274 computed for all the supported systems (@pxref{Derivations}).
14276 @item profile-collisions
14277 Check whether installing the given packages in a profile would lead to
14278 collisions. Collisions occur when several packages with the same name
14279 but a different version or a different store file name are propagated.
14280 @xref{package Reference, @code{propagated-inputs}}, for more information
14281 on propagated inputs.
14284 @cindex Software Heritage, source code archive
14285 @cindex archival of source code, Software Heritage
14286 Checks whether the package's source code is archived at
14287 @uref{https://www.softwareheritage.org, Software Heritage}.
14289 When the source code that is not archived comes from a version-control system
14290 (VCS)---e.g., it's obtained with @code{git-fetch}, send Software Heritage a
14291 ``save'' request so that it eventually archives it. This ensures that the
14292 source will remain available in the long term, and that Guix can fall back to
14293 Software Heritage should the source code disappear from its original host.
14294 The status of recent ``save'' requests can be
14295 @uref{https://archive.softwareheritage.org/save/#requests, viewed on-line}.
14297 When source code is a tarball obtained with @code{url-fetch}, simply print a
14298 message when it is not archived. As of this writing, Software Heritage does
14299 not allow requests to save arbitrary tarballs; we are working on ways to
14300 ensure that non-VCS source code is also archived.
14303 @uref{https://archive.softwareheritage.org/api/#rate-limiting, limits the
14304 request rate per IP address}. When the limit is reached, @command{guix lint}
14305 prints a message and the @code{archival} checker stops doing anything until
14306 that limit has been reset.
14309 @cindex security vulnerabilities
14310 @cindex CVE, Common Vulnerabilities and Exposures
14311 Report known vulnerabilities found in the Common Vulnerabilities and
14312 Exposures (CVE) databases of the current and past year
14313 @uref{https://nvd.nist.gov/vuln/data-feeds, published by the US
14316 To view information about a particular vulnerability, visit pages such as:
14320 @indicateurl{https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-YYYY-ABCD}
14322 @indicateurl{https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-YYYY-ABCD}
14326 where @code{CVE-YYYY-ABCD} is the CVE identifier---e.g.,
14327 @code{CVE-2015-7554}.
14329 Package developers can specify in package recipes the
14330 @uref{https://nvd.nist.gov/products/cpe,Common Platform Enumeration (CPE)}
14331 name and version of the package when they differ from the name or version
14332 that Guix uses, as in this example:
14338 ;; CPE calls this package "grub2".
14339 (properties '((cpe-name . "grub2")
14340 (cpe-version . "2.3"))))
14343 @c See <https://www.openwall.com/lists/oss-security/2017/03/15/3>.
14344 Some entries in the CVE database do not specify which version of a
14345 package they apply to, and would thus ``stick around'' forever. Package
14346 developers who found CVE alerts and verified they can be ignored can
14347 declare them as in this example:
14353 ;; These CVEs no longer apply and can be safely ignored.
14354 (properties `((lint-hidden-cve . ("CVE-2011-0433"
14357 "CVE-2011-5244")))))
14361 Warn about obvious source code formatting issues: trailing white space,
14362 use of tabulations, etc.
14365 Report old-style input labels that do not match the name of the
14366 corresponding package. This aims to help migrate from the ``old input
14367 style''. @xref{package Reference}, for more information on package
14368 inputs and input styles. @xref{Invoking guix style}, on how to migrate
14372 The general syntax is:
14375 guix lint @var{options} @var{package}@dots{}
14378 If no package is given on the command line, then all packages are checked.
14379 The @var{options} may be zero or more of the following:
14382 @item --list-checkers
14384 List and describe all the available checkers that will be run on packages
14389 Only enable the checkers specified in a comma-separated list using the
14390 names returned by @option{--list-checkers}.
14394 Only disable the checkers specified in a comma-separated list using the
14395 names returned by @option{--list-checkers}.
14397 @item --expression=@var{expr}
14398 @itemx -e @var{expr}
14399 Consider the package @var{expr} evaluates to.
14401 This is useful to unambiguously designate packages, as in this example:
14404 guix lint -c archival -e '(@@ (gnu packages guile) guile-3.0)'
14409 Only enable the checkers that do not depend on Internet access.
14411 @item --load-path=@var{directory}
14412 @itemx -L @var{directory}
14413 Add @var{directory} to the front of the package module search path
14414 (@pxref{Package Modules}).
14416 This allows users to define their own packages and make them visible to
14417 the command-line tools.
14421 @node Invoking guix size
14422 @section Invoking @command{guix size}
14425 @cindex package size
14427 @cindex @command{guix size}
14428 The @command{guix size} command helps package developers profile the
14429 disk usage of packages. It is easy to overlook the impact of an
14430 additional dependency added to a package, or the impact of using a
14431 single output for a package that could easily be split (@pxref{Packages
14432 with Multiple Outputs}). Such are the typical issues that
14433 @command{guix size} can highlight.
14435 The command can be passed one or more package specifications
14436 such as @code{gcc@@4.8}
14437 or @code{guile:debug}, or a file name in the store. Consider this
14441 $ guix size coreutils
14442 store item total self
14443 /gnu/store/@dots{}-gcc-5.5.0-lib 60.4 30.1 38.1%
14444 /gnu/store/@dots{}-glibc-2.27 30.3 28.8 36.6%
14445 /gnu/store/@dots{}-coreutils-8.28 78.9 15.0 19.0%
14446 /gnu/store/@dots{}-gmp-6.1.2 63.1 2.7 3.4%
14447 /gnu/store/@dots{}-bash-static-4.4.12 1.5 1.5 1.9%
14448 /gnu/store/@dots{}-acl-2.2.52 61.1 0.4 0.5%
14449 /gnu/store/@dots{}-attr-2.4.47 60.6 0.2 0.3%
14450 /gnu/store/@dots{}-libcap-2.25 60.5 0.2 0.2%
14455 The store items listed here constitute the @dfn{transitive closure} of
14456 Coreutils---i.e., Coreutils and all its dependencies, recursively---as
14457 would be returned by:
14460 $ guix gc -R /gnu/store/@dots{}-coreutils-8.23
14463 Here the output shows three columns next to store items. The first column,
14464 labeled ``total'', shows the size in mebibytes (MiB) of the closure of
14465 the store item---that is, its own size plus the size of all its
14466 dependencies. The next column, labeled ``self'', shows the size of the
14467 item itself. The last column shows the ratio of the size of the item
14468 itself to the space occupied by all the items listed here.
14470 In this example, we see that the closure of Coreutils weighs in at
14471 79@tie{}MiB, most of which is taken by libc and GCC's run-time support
14472 libraries. (That libc and GCC's libraries represent a large fraction of
14473 the closure is not a problem @i{per se} because they are always available
14474 on the system anyway.)
14476 Since the command also accepts store file names, assessing the size of
14477 a build result is straightforward:
14480 guix size $(guix system build config.scm)
14483 When the package(s) passed to @command{guix size} are available in the
14484 store@footnote{More precisely, @command{guix size} looks for the
14485 @emph{ungrafted} variant of the given package(s), as returned by
14486 @code{guix build @var{package} --no-grafts}. @xref{Security Updates},
14487 for information on grafts.}, @command{guix size} queries the daemon to determine its
14488 dependencies, and measures its size in the store, similar to @command{du
14489 -ms --apparent-size} (@pxref{du invocation,,, coreutils, GNU
14492 When the given packages are @emph{not} in the store, @command{guix size}
14493 reports information based on the available substitutes
14494 (@pxref{Substitutes}). This makes it possible it to profile disk usage of
14495 store items that are not even on disk, only available remotely.
14497 You can also specify several package names:
14500 $ guix size coreutils grep sed bash
14501 store item total self
14502 /gnu/store/@dots{}-coreutils-8.24 77.8 13.8 13.4%
14503 /gnu/store/@dots{}-grep-2.22 73.1 0.8 0.8%
14504 /gnu/store/@dots{}-bash-4.3.42 72.3 4.7 4.6%
14505 /gnu/store/@dots{}-readline-6.3 67.6 1.2 1.2%
14511 In this example we see that the combination of the four packages takes
14512 102.3@tie{}MiB in total, which is much less than the sum of each closure
14513 since they have a lot of dependencies in common.
14515 When looking at the profile returned by @command{guix size}, you may
14516 find yourself wondering why a given package shows up in the profile at
14517 all. To understand it, you can use @command{guix graph --path -t
14518 references} to display the shortest path between the two packages
14519 (@pxref{Invoking guix graph}).
14521 The available options are:
14525 @item --substitute-urls=@var{urls}
14526 Use substitute information from @var{urls}.
14527 @xref{client-substitute-urls, the same option for @code{guix build}}.
14529 @item --sort=@var{key}
14530 Sort lines according to @var{key}, one of the following options:
14534 the size of each item (the default);
14536 the total size of the item's closure.
14539 @item --map-file=@var{file}
14540 Write a graphical map of disk usage in PNG format to @var{file}.
14542 For the example above, the map looks like this:
14544 @image{images/coreutils-size-map,5in,, map of Coreutils disk usage
14545 produced by @command{guix size}}
14547 This option requires that
14548 @uref{https://wingolog.org/software/guile-charting/, Guile-Charting} be
14549 installed and visible in Guile's module search path. When that is not
14550 the case, @command{guix size} fails as it tries to load it.
14552 @item --system=@var{system}
14553 @itemx -s @var{system}
14554 Consider packages for @var{system}---e.g., @code{x86_64-linux}.
14556 @item --load-path=@var{directory}
14557 @itemx -L @var{directory}
14558 Add @var{directory} to the front of the package module search path
14559 (@pxref{Package Modules}).
14561 This allows users to define their own packages and make them visible to
14562 the command-line tools.
14565 @node Invoking guix graph
14566 @section Invoking @command{guix graph}
14569 @cindex @command{guix graph}
14570 @cindex package dependencies
14571 Packages and their dependencies form a @dfn{graph}, specifically a
14572 directed acyclic graph (DAG). It can quickly become difficult to have a
14573 mental model of the package DAG, so the @command{guix graph} command
14574 provides a visual representation of the DAG@. By default,
14575 @command{guix graph} emits a DAG representation in the input format of
14576 @uref{https://www.graphviz.org/, Graphviz}, so its output can be passed
14577 directly to the @command{dot} command of Graphviz. It can also emit an
14578 HTML page with embedded JavaScript code to display a ``chord diagram''
14579 in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or
14580 emit Cypher queries to construct a graph in a graph database supporting
14581 the @uref{https://www.opencypher.org/, openCypher} query language. With
14582 @option{--path}, it simply displays the shortest path between two
14583 packages. The general syntax is:
14586 guix graph @var{options} @var{package}@dots{}
14589 For example, the following command generates a PDF file representing the
14590 package DAG for the GNU@tie{}Core Utilities, showing its build-time
14594 guix graph coreutils | dot -Tpdf > dag.pdf
14597 The output looks like this:
14599 @image{images/coreutils-graph,2in,,Dependency graph of the GNU Coreutils}
14601 Nice little graph, no?
14603 You may find it more pleasant to navigate the graph interactively with
14604 @command{xdot} (from the @code{xdot} package):
14607 guix graph coreutils | xdot -
14610 But there is more than one graph! The one above is concise: it is the
14611 graph of package objects, omitting implicit inputs such as GCC, libc,
14612 grep, etc. It is often useful to have such a concise graph, but
14613 sometimes one may want to see more details. @command{guix graph} supports
14614 several types of graphs, allowing you to choose the level of detail:
14618 This is the default type used in the example above. It shows the DAG of
14619 package objects, excluding implicit dependencies. It is concise, but
14620 filters out many details.
14622 @item reverse-package
14623 This shows the @emph{reverse} DAG of packages. For example:
14626 guix graph --type=reverse-package ocaml
14629 ...@: yields the graph of packages that @emph{explicitly} depend on OCaml (if
14630 you are also interested in cases where OCaml is an implicit dependency, see
14631 @code{reverse-bag} below).
14633 Note that for core packages this can yield huge graphs. If all you want
14634 is to know the number of packages that depend on a given package, use
14635 @command{guix refresh --list-dependent} (@pxref{Invoking guix refresh,
14636 @option{--list-dependent}}).
14639 This is the package DAG, @emph{including} implicit inputs.
14641 For instance, the following command:
14644 guix graph --type=bag-emerged coreutils
14647 ...@: yields this bigger graph:
14649 @image{images/coreutils-bag-graph,,5in,Detailed dependency graph of the GNU Coreutils}
14651 At the bottom of the graph, we see all the implicit inputs of
14652 @var{gnu-build-system} (@pxref{Build Systems, @code{gnu-build-system}}).
14654 Now, note that the dependencies of these implicit inputs---that is, the
14655 @dfn{bootstrap dependencies} (@pxref{Bootstrapping})---are not shown
14656 here, for conciseness.
14659 Similar to @code{bag-emerged}, but this time including all the bootstrap
14662 @item bag-with-origins
14663 Similar to @code{bag}, but also showing origins and their dependencies.
14666 This shows the @emph{reverse} DAG of packages. Unlike @code{reverse-package},
14667 it also takes implicit dependencies into account. For example:
14670 guix graph -t reverse-bag dune
14674 ...@: yields the graph of all packages that depend on Dune, directly or
14675 indirectly. Since Dune is an @emph{implicit} dependency of many packages
14676 @i{via} @code{dune-build-system}, this shows a large number of packages,
14677 whereas @code{reverse-package} would show very few if any.
14680 This is the most detailed representation: It shows the DAG of
14681 derivations (@pxref{Derivations}) and plain store items. Compared to
14682 the above representation, many additional nodes are visible, including
14683 build scripts, patches, Guile modules, etc.
14685 For this type of graph, it is also possible to pass a @file{.drv} file
14686 name instead of a package name, as in:
14689 guix graph -t derivation $(guix system build -d my-config.scm)
14693 This is the graph of @dfn{package modules} (@pxref{Package Modules}).
14694 For example, the following command shows the graph for the package
14695 module that defines the @code{guile} package:
14698 guix graph -t module guile | xdot -
14702 All the types above correspond to @emph{build-time dependencies}. The
14703 following graph type represents the @emph{run-time dependencies}:
14707 This is the graph of @dfn{references} of a package output, as returned
14708 by @command{guix gc --references} (@pxref{Invoking guix gc}).
14710 If the given package output is not available in the store, @command{guix
14711 graph} attempts to obtain dependency information from substitutes.
14713 Here you can also pass a store file name instead of a package name. For
14714 example, the command below produces the reference graph of your profile
14715 (which can be big!):
14718 guix graph -t references $(readlink -f ~/.guix-profile)
14722 This is the graph of the @dfn{referrers} of a store item, as returned by
14723 @command{guix gc --referrers} (@pxref{Invoking guix gc}).
14725 This relies exclusively on local information from your store. For
14726 instance, let us suppose that the current Inkscape is available in 10
14727 profiles on your machine; @command{guix graph -t referrers inkscape}
14728 will show a graph rooted at Inkscape and with those 10 profiles linked
14731 It can help determine what is preventing a store item from being garbage
14736 @cindex shortest path, between packages
14737 Often, the graph of the package you are interested in does not fit on
14738 your screen, and anyway all you want to know is @emph{why} that package
14739 actually depends on some seemingly unrelated package. The
14740 @option{--path} option instructs @command{guix graph} to display the
14741 shortest path between two packages (or derivations, or store items,
14745 $ guix graph --path emacs libunistring
14748 libunistring@@0.9.10
14749 $ guix graph --path -t derivation emacs libunistring
14750 /gnu/store/@dots{}-emacs-26.3.drv
14751 /gnu/store/@dots{}-mailutils-3.9.drv
14752 /gnu/store/@dots{}-libunistring-0.9.10.drv
14753 $ guix graph --path -t references emacs libunistring
14754 /gnu/store/@dots{}-emacs-26.3
14755 /gnu/store/@dots{}-libidn2-2.2.0
14756 /gnu/store/@dots{}-libunistring-0.9.10
14759 Sometimes you still want to visualize the graph but would like to trim
14760 it so it can actually be displayed. One way to do it is via the
14761 @option{--max-depth} (or @option{-M}) option, which lets you specify the
14762 maximum depth of the graph. In the example below, we visualize only
14763 @code{libreoffice} and the nodes whose distance to @code{libreoffice} is
14767 guix graph -M 2 libreoffice | xdot -f fdp -
14770 Mind you, that's still a big ball of spaghetti, but at least
14771 @command{dot} can render it quickly and it can be browsed somewhat.
14773 The available options are the following:
14776 @item --type=@var{type}
14777 @itemx -t @var{type}
14778 Produce a graph output of @var{type}, where @var{type} must be one of
14779 the values listed above.
14782 List the supported graph types.
14784 @item --backend=@var{backend}
14785 @itemx -b @var{backend}
14786 Produce a graph using the selected @var{backend}.
14788 @item --list-backends
14789 List the supported graph backends.
14791 Currently, the available backends are Graphviz and d3.js.
14794 Display the shortest path between two nodes of the type specified by
14795 @option{--type}. The example below shows the shortest path between
14796 @code{libreoffice} and @code{llvm} according to the references of
14797 @code{libreoffice}:
14800 $ guix graph --path -t references libreoffice llvm
14801 /gnu/store/@dots{}-libreoffice-6.4.2.2
14802 /gnu/store/@dots{}-libepoxy-1.5.4
14803 /gnu/store/@dots{}-mesa-19.3.4
14804 /gnu/store/@dots{}-llvm-9.0.1
14807 @item --expression=@var{expr}
14808 @itemx -e @var{expr}
14809 Consider the package @var{expr} evaluates to.
14811 This is useful to precisely refer to a package, as in this example:
14814 guix graph -e '(@@@@ (gnu packages commencement) gnu-make-final)'
14817 @item --system=@var{system}
14818 @itemx -s @var{system}
14819 Display the graph for @var{system}---e.g., @code{i686-linux}.
14821 The package dependency graph is largely architecture-independent, but there
14822 are some architecture-dependent bits that this option allows you to visualize.
14824 @item --load-path=@var{directory}
14825 @itemx -L @var{directory}
14826 Add @var{directory} to the front of the package module search path
14827 (@pxref{Package Modules}).
14829 This allows users to define their own packages and make them visible to
14830 the command-line tools.
14833 On top of that, @command{guix graph} supports all the usual package
14834 transformation options (@pxref{Package Transformation Options}). This
14835 makes it easy to view the effect of a graph-rewriting transformation
14836 such as @option{--with-input}. For example, the command below outputs
14837 the graph of @code{git} once @code{openssl} has been replaced by
14838 @code{libressl} everywhere in the graph:
14841 guix graph git --with-input=openssl=libressl
14844 So many possibilities, so much fun!
14846 @node Invoking guix publish
14847 @section Invoking @command{guix publish}
14849 @cindex @command{guix publish}
14850 The purpose of @command{guix publish} is to enable users to easily share
14851 their store with others, who can then use it as a substitute server
14852 (@pxref{Substitutes}).
14854 When @command{guix publish} runs, it spawns an HTTP server which allows
14855 anyone with network access to obtain substitutes from it. This means
14856 that any machine running Guix can also act as if it were a build farm,
14857 since the HTTP interface is compatible with Cuirass, the software behind
14858 the @code{@value{SUBSTITUTE-SERVER-1}} build farm.
14860 For security, each substitute is signed, allowing recipients to check
14861 their authenticity and integrity (@pxref{Substitutes}). Because
14862 @command{guix publish} uses the signing key of the system, which is only
14863 readable by the system administrator, it must be started as root; the
14864 @option{--user} option makes it drop root privileges early on.
14866 The signing key pair must be generated before @command{guix publish} is
14867 launched, using @command{guix archive --generate-key} (@pxref{Invoking
14870 When the @option{--advertise} option is passed, the server advertises
14871 its availability on the local network using multicast DNS (mDNS) and DNS
14872 service discovery (DNS-SD), currently @i{via} Guile-Avahi (@pxref{Top,,,
14873 guile-avahi, Using Avahi in Guile Scheme Programs}).
14875 The general syntax is:
14878 guix publish @var{options}@dots{}
14881 Running @command{guix publish} without any additional arguments will
14882 spawn an HTTP server on port 8080:
14888 @cindex socket activation, for @command{guix publish}
14889 @command{guix publish} can also be started following the systemd
14890 ``socket activation'' protocol (@pxref{Service De- and Constructors,
14891 @code{make-systemd-constructor},, shepherd, The GNU Shepherd Manual}).
14893 Once a publishing server has been authorized, the daemon may download
14894 substitutes from it. @xref{Getting Substitutes from Other Servers}.
14896 By default, @command{guix publish} compresses archives on the fly as it
14897 serves them. This ``on-the-fly'' mode is convenient in that it requires
14898 no setup and is immediately available. However, when serving lots of
14899 clients, we recommend using the @option{--cache} option, which enables
14900 caching of the archives before they are sent to clients---see below for
14901 details. The @command{guix weather} command provides a handy way to
14902 check what a server provides (@pxref{Invoking guix weather}).
14904 As a bonus, @command{guix publish} also serves as a content-addressed
14905 mirror for source files referenced in @code{origin} records
14906 (@pxref{origin Reference}). For instance, assuming @command{guix
14907 publish} is running on @code{example.org}, the following URL returns the
14908 raw @file{hello-2.10.tar.gz} file with the given SHA256 hash
14909 (represented in @code{nix-base32} format, @pxref{Invoking guix hash}):
14912 http://example.org/file/hello-2.10.tar.gz/sha256/0ssi1@dots{}ndq1i
14915 Obviously, these URLs only work for files that are in the store; in
14916 other cases, they return 404 (``Not Found'').
14918 @cindex build logs, publication
14919 Build logs are available from @code{/log} URLs like:
14922 http://example.org/log/gwspk@dots{}-guile-2.2.3
14926 When @command{guix-daemon} is configured to save compressed build logs,
14927 as is the case by default (@pxref{Invoking guix-daemon}), @code{/log}
14928 URLs return the compressed log as-is, with an appropriate
14929 @code{Content-Type} and/or @code{Content-Encoding} header. We recommend
14930 running @command{guix-daemon} with @option{--log-compression=gzip} since
14931 Web browsers can automatically decompress it, which is not the case with
14934 The following options are available:
14937 @item --port=@var{port}
14938 @itemx -p @var{port}
14939 Listen for HTTP requests on @var{port}.
14941 @item --listen=@var{host}
14942 Listen on the network interface for @var{host}. The default is to
14943 accept connections from any interface.
14945 @item --user=@var{user}
14946 @itemx -u @var{user}
14947 Change privileges to @var{user} as soon as possible---i.e., once the
14948 server socket is open and the signing key has been read.
14950 @item --compression[=@var{method}[:@var{level}]]
14951 @itemx -C [@var{method}[:@var{level}]]
14952 Compress data using the given @var{method} and @var{level}. @var{method} is
14953 one of @code{lzip}, @code{zstd}, and @code{gzip}; when @var{method} is
14954 omitted, @code{gzip} is used.
14956 When @var{level} is zero, disable compression. The range 1 to 9 corresponds
14957 to different compression levels: 1 is the fastest, and 9 is the best
14958 (CPU-intensive). The default is 3.
14960 Usually, @code{lzip} compresses noticeably better than @code{gzip} for a
14961 small increase in CPU usage; see
14962 @uref{https://nongnu.org/lzip/lzip_benchmark.html,benchmarks on the lzip
14963 Web page}. However, @code{lzip} achieves low decompression throughput
14964 (on the order of 50@tie{}MiB/s on modern hardware), which can be a
14965 bottleneck for someone who downloads over a fast network connection.
14967 The compression ratio of @code{zstd} is between that of @code{lzip} and
14968 that of @code{gzip}; its main advantage is a
14969 @uref{https://facebook.github.io/zstd/,high decompression speed}.
14971 Unless @option{--cache} is used, compression occurs on the fly and
14972 the compressed streams are not
14973 cached. Thus, to reduce load on the machine that runs @command{guix
14974 publish}, it may be a good idea to choose a low compression level, to
14975 run @command{guix publish} behind a caching proxy, or to use
14976 @option{--cache}. Using @option{--cache} has the advantage that it
14977 allows @command{guix publish} to add @code{Content-Length} HTTP header
14980 This option can be repeated, in which case every substitute gets compressed
14981 using all the selected methods, and all of them are advertised. This is
14982 useful when users may not support all the compression methods: they can select
14983 the one they support.
14985 @item --cache=@var{directory}
14986 @itemx -c @var{directory}
14987 Cache archives and meta-data (@code{.narinfo} URLs) to @var{directory}
14988 and only serve archives that are in cache.
14990 When this option is omitted, archives and meta-data are created
14991 on-the-fly. This can reduce the available bandwidth, especially when
14992 compression is enabled, since this may become CPU-bound. Another
14993 drawback of the default mode is that the length of archives is not known
14994 in advance, so @command{guix publish} does not add a
14995 @code{Content-Length} HTTP header to its responses, which in turn
14996 prevents clients from knowing the amount of data being downloaded.
14998 Conversely, when @option{--cache} is used, the first request for a store
14999 item (@i{via} a @code{.narinfo} URL) triggers a
15000 background process to @dfn{bake} the archive---computing its
15001 @code{.narinfo} and compressing the archive, if needed. Once the
15002 archive is cached in @var{directory}, subsequent requests succeed and
15003 are served directly from the cache, which guarantees that clients get
15004 the best possible bandwidth.
15006 That first @code{.narinfo} request nonetheless returns 200, provided the
15007 requested store item is ``small enough'', below the cache bypass
15008 threshold---see @option{--cache-bypass-threshold} below. That way,
15009 clients do not have to wait until the archive is baked. For larger
15010 store items, the first @code{.narinfo} request returns 404, meaning that
15011 clients have to wait until the archive is baked.
15013 The ``baking'' process is performed by worker threads. By default, one
15014 thread per CPU core is created, but this can be customized. See
15015 @option{--workers} below.
15017 When @option{--ttl} is used, cached entries are automatically deleted
15018 when they have expired.
15020 @item --workers=@var{N}
15021 When @option{--cache} is used, request the allocation of @var{N} worker
15022 threads to ``bake'' archives.
15024 @item --ttl=@var{ttl}
15025 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
15026 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
15027 days, @code{1m} means 1 month, and so on.
15029 This allows the user's Guix to keep substitute information in cache for
15030 @var{ttl}. However, note that @code{guix publish} does not itself
15031 guarantee that the store items it provides will indeed remain available
15032 for as long as @var{ttl}.
15034 Additionally, when @option{--cache} is used, cached entries that have
15035 not been accessed for @var{ttl} and that no longer have a corresponding
15036 item in the store, may be deleted.
15038 @item --negative-ttl=@var{ttl}
15039 Similarly produce @code{Cache-Control} HTTP headers to advertise the
15040 time-to-live (TTL) of @emph{negative} lookups---missing store items, for
15041 which the HTTP 404 code is returned. By default, no negative TTL is
15044 This parameter can help adjust server load and substitute latency by
15045 instructing cooperating clients to be more or less patient when a store
15048 @item --cache-bypass-threshold=@var{size}
15049 When used in conjunction with @option{--cache}, store items smaller than
15050 @var{size} are immediately available, even when they are not yet in
15051 cache. @var{size} is a size in bytes, or it can be suffixed by @code{M}
15052 for megabytes and so on. The default is @code{10M}.
15054 ``Cache bypass'' allows you to reduce the publication delay for clients
15055 at the expense of possibly additional I/O and CPU use on the server
15056 side: depending on the client access patterns, those store items can end
15057 up being baked several times until a copy is available in cache.
15059 Increasing the threshold may be useful for sites that have few users, or
15060 to guarantee that users get substitutes even for store items that are
15063 @item --nar-path=@var{path}
15064 Use @var{path} as the prefix for the URLs of ``nar'' files
15065 (@pxref{Invoking guix archive, normalized archives}).
15067 By default, nars are served at a URL such as
15068 @code{/nar/gzip/@dots{}-coreutils-8.25}. This option allows you to
15069 change the @code{/nar} part to @var{path}.
15071 @item --public-key=@var{file}
15072 @itemx --private-key=@var{file}
15073 Use the specific @var{file}s as the public/private key pair used to sign
15074 the store items being published.
15076 The files must correspond to the same key pair (the private key is used
15077 for signing and the public key is merely advertised in the signature
15078 metadata). They must contain keys in the canonical s-expression format
15079 as produced by @command{guix archive --generate-key} (@pxref{Invoking
15080 guix archive}). By default, @file{/etc/guix/signing-key.pub} and
15081 @file{/etc/guix/signing-key.sec} are used.
15083 @item --repl[=@var{port}]
15084 @itemx -r [@var{port}]
15085 Spawn a Guile REPL server (@pxref{REPL Servers,,, guile, GNU Guile
15086 Reference Manual}) on @var{port} (37146 by default). This is used
15087 primarily for debugging a running @command{guix publish} server.
15090 Enabling @command{guix publish} on Guix System is a one-liner: just
15091 instantiate a @code{guix-publish-service-type} service in the @code{services} field
15092 of the @code{operating-system} declaration (@pxref{guix-publish-service-type,
15093 @code{guix-publish-service-type}}).
15095 If you are instead running Guix on a ``foreign distro'', follow these
15100 If your host distro uses the systemd init system:
15103 # ln -s ~root/.guix-profile/lib/systemd/system/guix-publish.service \
15104 /etc/systemd/system/
15105 # systemctl start guix-publish && systemctl enable guix-publish
15109 If your host distro uses the Upstart init system:
15112 # ln -s ~root/.guix-profile/lib/upstart/system/guix-publish.conf /etc/init/
15113 # start guix-publish
15117 Otherwise, proceed similarly with your distro's init system.
15120 @node Invoking guix challenge
15121 @section Invoking @command{guix challenge}
15123 @cindex reproducible builds
15124 @cindex verifiable builds
15125 @cindex @command{guix challenge}
15127 Do the binaries provided by this server really correspond to the source
15128 code it claims to build? Is a package build process deterministic?
15129 These are the questions the @command{guix challenge} command attempts to
15132 The former is obviously an important question: Before using a substitute
15133 server (@pxref{Substitutes}), one had better @emph{verify} that it
15134 provides the right binaries, and thus @emph{challenge} it. The latter
15135 is what enables the former: If package builds are deterministic, then
15136 independent builds of the package should yield the exact same result,
15137 bit for bit; if a server provides a binary different from the one
15138 obtained locally, it may be either corrupt or malicious.
15140 We know that the hash that shows up in @file{/gnu/store} file names is
15141 the hash of all the inputs of the process that built the file or
15142 directory---compilers, libraries, build scripts,
15143 etc. (@pxref{Introduction}). Assuming deterministic build processes,
15144 one store file name should map to exactly one build output.
15145 @command{guix challenge} checks whether there is, indeed, a single
15146 mapping by comparing the build outputs of several independent builds of
15147 any given store item.
15149 The command output looks like this:
15153 --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org" \
15154 openssl git pius coreutils grep
15155 updating substitutes from 'https://@value{SUBSTITUTE-SERVER-1}'... 100.0%
15156 updating substitutes from 'https://guix.example.org'... 100.0%
15157 /gnu/store/@dots{}-openssl-1.0.2d contents differ:
15158 local hash: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
15159 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-openssl-1.0.2d: 0725l22r5jnzazaacncwsvp9kgf42266ayyp814v7djxs7nk963q
15160 https://guix.example.org/nar/@dots{}-openssl-1.0.2d: 1zy4fmaaqcnjrzzajkdn3f5gmjk754b43qkq47llbyak9z0qjyim
15162 /lib/libcrypto.so.1.1
15165 /gnu/store/@dots{}-git-2.5.0 contents differ:
15166 local hash: 00p3bmryhjxrhpn2gxs2fy0a15lnip05l97205pgbk5ra395hyha
15167 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-git-2.5.0: 069nb85bv4d4a6slrwjdy8v1cn4cwspm3kdbmyb81d6zckj3nq9f
15168 https://guix.example.org/nar/@dots{}-git-2.5.0: 0mdqa9w1p6cmli6976v4wi0sw9r4p5prkj7lzfd1877wk11c9c73
15170 /libexec/git-core/git-fsck
15172 /gnu/store/@dots{}-pius-2.1.1 contents differ:
15173 local hash: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
15174 https://@value{SUBSTITUTE-SERVER-1}/nar/@dots{}-pius-2.1.1: 0k4v3m9z1zp8xzzizb7d8kjj72f9172xv078sq4wl73vnq9ig3ax
15175 https://guix.example.org/nar/@dots{}-pius-2.1.1: 1cy25x1a4fzq5rk0pmvc8xhwyffnqz95h2bpvqsz2mpvlbccy0gs
15177 /share/man/man1/pius.1.gz
15181 5 store items were analyzed:
15182 - 2 (40.0%) were identical
15183 - 3 (60.0%) differed
15184 - 0 (0.0%) were inconclusive
15188 In this example, @command{guix challenge} queries all the substitute
15189 servers for each of the fives packages specified on the command line.
15190 It then reports those store items for which the servers obtained a
15191 result different from the local build (if it exists) and/or different
15192 from one another; here, the @samp{local hash} lines indicate that a
15193 local build result was available for each of these packages and shows
15196 @cindex non-determinism, in package builds
15197 As an example, @code{guix.example.org} always gets a different answer.
15198 Conversely, @code{@value{SUBSTITUTE-SERVER-1}} agrees with local builds, except in the
15199 case of Git. This might indicate that the build process of Git is
15200 non-deterministic, meaning that its output varies as a function of
15201 various things that Guix does not fully control, in spite of building
15202 packages in isolated environments (@pxref{Features}). Most common
15203 sources of non-determinism include the addition of timestamps in build
15204 results, the inclusion of random numbers, and directory listings sorted
15205 by inode number. See @uref{https://reproducible-builds.org/docs/}, for
15208 To find out what is wrong with this Git binary, the easiest approach is
15212 guix challenge git \
15213 --diff=diffoscope \
15214 --substitute-urls="https://@value{SUBSTITUTE-SERVER-1} https://guix.example.org"
15217 This automatically invokes @command{diffoscope}, which displays detailed
15218 information about files that differ.
15220 Alternatively, we can do something along these lines (@pxref{Invoking guix
15224 $ wget -q -O - https://@value{SUBSTITUTE-SERVER-1}/nar/lzip/@dots{}-git-2.5.0 \
15225 | lzip -d | guix archive -x /tmp/git
15226 $ diff -ur --no-dereference /gnu/store/@dots{}-git.2.5.0 /tmp/git
15229 This command shows the difference between the files resulting from the
15230 local build, and the files resulting from the build on
15231 @code{@value{SUBSTITUTE-SERVER-1}} (@pxref{Overview, Comparing and Merging Files,,
15232 diffutils, Comparing and Merging Files}). The @command{diff} command
15233 works great for text files. When binary files differ, a better option
15234 is @uref{https://diffoscope.org/, Diffoscope}, a tool that helps
15235 visualize differences for all kinds of files.
15237 Once you have done that work, you can tell whether the differences are due
15238 to a non-deterministic build process or to a malicious server. We try
15239 hard to remove sources of non-determinism in packages to make it easier
15240 to verify substitutes, but of course, this is a process that
15241 involves not just Guix, but a large part of the free software community.
15242 In the meantime, @command{guix challenge} is one tool to help address
15245 If you are writing packages for Guix, you are encouraged to check
15246 whether @code{@value{SUBSTITUTE-SERVER-1}} and other substitute servers obtain the
15247 same build result as you did with:
15250 guix challenge @var{package}
15253 The general syntax is:
15256 guix challenge @var{options} @var{argument}@dots{}
15260 where @var{argument} is a package specification such as
15261 @code{guile@@2.0} or @code{glibc:debug} or, alternatively, a store file
15262 name as returned, for example, by @command{guix build} or @command{guix
15265 When a difference is found between the hash of a locally-built item and
15266 that of a server-provided substitute, or among substitutes provided by
15267 different servers, the command displays it as in the example above and
15268 its exit code is 2 (other non-zero exit codes denote other kinds of
15271 The one option that matters is:
15275 @item --substitute-urls=@var{urls}
15276 Consider @var{urls} the whitespace-separated list of substitute source
15277 URLs to compare to.
15279 @item --diff=@var{mode}
15280 Upon mismatches, show differences according to @var{mode}, one of:
15283 @item @code{simple} (the default)
15284 Show the list of files that differ.
15286 @item @code{diffoscope}
15287 @itemx @var{command}
15288 Invoke @uref{https://diffoscope.org/, Diffoscope}, passing it
15289 two directories whose contents do not match.
15291 When @var{command} is an absolute file name, run @var{command} instead
15295 Do not show further details about the differences.
15298 Thus, unless @option{--diff=none} is passed, @command{guix challenge}
15299 downloads the store items from the given substitute servers so that it
15304 Show details about matches (identical contents) in addition to
15305 information about mismatches.
15309 @node Invoking guix copy
15310 @section Invoking @command{guix copy}
15312 @cindex copy, of store items, over SSH
15313 @cindex SSH, copy of store items
15314 @cindex sharing store items across machines
15315 @cindex transferring store items across machines
15316 The @command{guix copy} command copies items from the store of one
15317 machine to that of another machine over a secure shell (SSH)
15318 connection@footnote{This command is available only when Guile-SSH was
15319 found. @xref{Requirements}, for details.}. For example, the following
15320 command copies the @code{coreutils} package, the user's profile, and all
15321 their dependencies over to @var{host}, logged in as @var{user}:
15324 guix copy --to=@var{user}@@@var{host} \
15325 coreutils $(readlink -f ~/.guix-profile)
15328 If some of the items to be copied are already present on @var{host},
15329 they are not actually sent.
15331 The command below retrieves @code{libreoffice} and @code{gimp} from
15332 @var{host}, assuming they are available there:
15335 guix copy --from=@var{host} libreoffice gimp
15338 The SSH connection is established using the Guile-SSH client, which is
15339 compatible with OpenSSH: it honors @file{~/.ssh/known_hosts} and
15340 @file{~/.ssh/config}, and uses the SSH agent for authentication.
15342 The key used to sign items that are sent must be accepted by the remote
15343 machine. Likewise, the key used by the remote machine to sign items you
15344 are retrieving must be in @file{/etc/guix/acl} so it is accepted by your
15345 own daemon. @xref{Invoking guix archive}, for more information about
15346 store item authentication.
15348 The general syntax is:
15351 guix copy [--to=@var{spec}|--from=@var{spec}] @var{items}@dots{}
15354 You must always specify one of the following options:
15357 @item --to=@var{spec}
15358 @itemx --from=@var{spec}
15359 Specify the host to send to or receive from. @var{spec} must be an SSH
15360 spec such as @code{example.org}, @code{charlie@@example.org}, or
15361 @code{charlie@@example.org:2222}.
15364 The @var{items} can be either package names, such as @code{gimp}, or
15365 store items, such as @file{/gnu/store/@dots{}-idutils-4.6}.
15367 When specifying the name of a package to send, it is first built if
15368 needed, unless @option{--dry-run} was specified. Common build options
15369 are supported (@pxref{Common Build Options}).
15372 @node Invoking guix container
15373 @section Invoking @command{guix container}
15375 @cindex @command{guix container}
15377 As of version @value{VERSION}, this tool is experimental. The interface
15378 is subject to radical change in the future.
15381 The purpose of @command{guix container} is to manipulate processes
15382 running within an isolated environment, commonly known as a
15383 ``container'', typically created by the @command{guix shell}
15384 (@pxref{Invoking guix shell}) and @command{guix system container}
15385 (@pxref{Invoking guix system}) commands.
15387 The general syntax is:
15390 guix container @var{action} @var{options}@dots{}
15393 @var{action} specifies the operation to perform with a container, and
15394 @var{options} specifies the context-specific arguments for the action.
15396 The following actions are available:
15400 Execute a command within the context of a running container.
15405 guix container exec @var{pid} @var{program} @var{arguments}@dots{}
15408 @var{pid} specifies the process ID of the running container.
15409 @var{program} specifies an executable file name within the root file
15410 system of the container. @var{arguments} are the additional options that
15411 will be passed to @var{program}.
15413 The following command launches an interactive login shell inside a
15414 Guix system container, started by @command{guix system container}, and whose
15415 process ID is 9001:
15418 guix container exec 9001 /run/current-system/profile/bin/bash --login
15421 Note that the @var{pid} cannot be the parent process of a container. It
15422 must be PID 1 of the container or one of its child processes.
15426 @node Invoking guix weather
15427 @section Invoking @command{guix weather}
15429 Occasionally you're grumpy because substitutes are lacking and you end
15430 up building packages by yourself (@pxref{Substitutes}). The
15431 @command{guix weather} command reports on substitute availability on the
15432 specified servers so you can have an idea of whether you'll be grumpy
15433 today. It can sometimes be useful info as a user, but it is primarily
15434 useful to people running @command{guix publish} (@pxref{Invoking guix
15437 @cindex statistics, for substitutes
15438 @cindex availability of substitutes
15439 @cindex substitute availability
15440 @cindex weather, substitute availability
15441 Here's a sample run:
15444 $ guix weather --substitute-urls=https://guix.example.org
15445 computing 5,872 package derivations for x86_64-linux...
15446 looking for 6,128 store items on https://guix.example.org..
15447 updating substitutes from 'https://guix.example.org'... 100.0%
15448 https://guix.example.org
15449 43.4% substitutes available (2,658 out of 6,128)
15450 7,032.5 MiB of nars (compressed)
15451 19,824.2 MiB on disk (uncompressed)
15452 0.030 seconds per request (182.9 seconds in total)
15453 33.5 requests per second
15455 9.8% (342 out of 3,470) of the missing items are queued
15457 x86_64-linux: 518 (59.7%)
15458 i686-linux: 221 (25.5%)
15459 aarch64-linux: 128 (14.8%)
15460 build rate: 23.41 builds per hour
15461 x86_64-linux: 11.16 builds per hour
15462 i686-linux: 6.03 builds per hour
15463 aarch64-linux: 6.41 builds per hour
15466 @cindex continuous integration, statistics
15467 As you can see, it reports the fraction of all the packages for which
15468 substitutes are available on the server---regardless of whether
15469 substitutes are enabled, and regardless of whether this server's signing
15470 key is authorized. It also reports the size of the compressed archives
15471 (``nars'') provided by the server, the size the corresponding store
15472 items occupy in the store (assuming deduplication is turned off), and
15473 the server's throughput. The second part gives continuous integration
15474 (CI) statistics, if the server supports it. In addition, using the
15475 @option{--coverage} option, @command{guix weather} can list ``important''
15476 package substitutes missing on the server (see below).
15478 To achieve that, @command{guix weather} queries over HTTP(S) meta-data
15479 (@dfn{narinfos}) for all the relevant store items. Like @command{guix
15480 challenge}, it ignores signatures on those substitutes, which is
15481 innocuous since the command only gathers statistics and cannot install
15484 The general syntax is:
15487 guix weather @var{options}@dots{} [@var{packages}@dots{}]
15490 When @var{packages} is omitted, @command{guix weather} checks the availability
15491 of substitutes for @emph{all} the packages, or for those specified with
15492 @option{--manifest}; otherwise it only considers the specified packages. It
15493 is also possible to query specific system types with @option{--system}.
15494 @command{guix weather} exits with a non-zero code when the fraction of
15495 available substitutes is below 100%.
15497 The available options are listed below.
15500 @item --substitute-urls=@var{urls}
15501 @var{urls} is the space-separated list of substitute server URLs to
15502 query. When this option is omitted, the default set of substitute
15503 servers is queried.
15505 @item --system=@var{system}
15506 @itemx -s @var{system}
15507 Query substitutes for @var{system}---e.g., @code{aarch64-linux}. This
15508 option can be repeated, in which case @command{guix weather} will query
15509 substitutes for several system types.
15511 @item --manifest=@var{file}
15512 Instead of querying substitutes for all the packages, only ask for those
15513 specified in @var{file}. @var{file} must contain a @dfn{manifest}, as
15514 with the @code{-m} option of @command{guix package} (@pxref{Invoking
15517 This option can be repeated several times, in which case the manifests
15520 @item --coverage[=@var{count}]
15521 @itemx -c [@var{count}]
15522 Report on substitute coverage for packages: list packages with at least
15523 @var{count} dependents (zero by default) for which substitutes are
15524 unavailable. Dependent packages themselves are not listed: if @var{b} depends
15525 on @var{a} and @var{a} has no substitutes, only @var{a} is listed, even though
15526 @var{b} usually lacks substitutes as well. The result looks like this:
15529 $ guix weather --substitute-urls=@value{SUBSTITUTE-URLS} -c 10
15530 computing 8,983 package derivations for x86_64-linux...
15531 looking for 9,343 store items on @value{SUBSTITUTE-URLS}...
15532 updating substitutes from '@value{SUBSTITUTE-URLS}'... 100.0%
15533 @value{SUBSTITUTE-URLS}
15534 64.7% substitutes available (6,047 out of 9,343)
15536 2502 packages are missing from '@value{SUBSTITUTE-URLS}' for 'x86_64-linux', among which:
15537 58 kcoreaddons@@5.49.0 /gnu/store/@dots{}-kcoreaddons-5.49.0
15538 46 qgpgme@@1.11.1 /gnu/store/@dots{}-qgpgme-1.11.1
15539 37 perl-http-cookiejar@@0.008 /gnu/store/@dots{}-perl-http-cookiejar-0.008
15543 What this example shows is that @code{kcoreaddons} and presumably the 58
15544 packages that depend on it have no substitutes at
15545 @code{@value{SUBSTITUTE-SERVER-1}}; likewise for @code{qgpgme} and the 46
15546 packages that depend on it.
15548 If you are a Guix developer, or if you are taking care of this build farm,
15549 you'll probably want to have a closer look at these packages: they may simply
15552 @item --display-missing
15553 Display the list of store items for which substitutes are missing.
15556 @node Invoking guix processes
15557 @section Invoking @command{guix processes}
15559 The @command{guix processes} command can be useful to developers and system
15560 administrators, especially on multi-user machines and on build farms: it lists
15561 the current sessions (connections to the daemon), as well as information about
15562 the processes involved@footnote{Remote sessions, when @command{guix-daemon} is
15563 started with @option{--listen} specifying a TCP endpoint, are @emph{not}
15564 listed.}. Here's an example of the information it returns:
15567 $ sudo guix processes
15570 ClientCommand: guix shell python
15574 ClientCommand: guix publish -u guix-publish -p 3000 -C 9 @dots{}
15578 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
15579 LockHeld: /gnu/store/@dots{}-perl-ipc-cmd-0.96.lock
15580 LockHeld: /gnu/store/@dots{}-python-six-bootstrap-1.11.0.lock
15581 LockHeld: /gnu/store/@dots{}-libjpeg-turbo-2.0.0.lock
15583 ChildCommand: guix offload x86_64-linux 7200 1 28800
15585 ChildCommand: guix offload x86_64-linux 7200 1 28800
15587 ChildCommand: guix offload x86_64-linux 7200 1 28800
15590 In this example we see that @command{guix-daemon} has three clients:
15591 @command{guix environment}, @command{guix publish}, and the Cuirass continuous
15592 integration tool; their process identifier (PID) is given by the
15593 @code{ClientPID} field. The @code{SessionPID} field gives the PID of the
15594 @command{guix-daemon} sub-process of this particular session.
15596 The @code{LockHeld} fields show which store items are currently locked
15597 by this session, which corresponds to store items being built or
15598 substituted (the @code{LockHeld} field is not displayed when
15599 @command{guix processes} is not running as root). Last, by looking at
15600 the @code{ChildPID} and @code{ChildCommand} fields, we understand that
15601 these three builds are being offloaded (@pxref{Daemon Offload Setup}).
15603 The output is in Recutils format so we can use the handy @command{recsel}
15604 command to select sessions of interest (@pxref{Selection Expressions,,,
15605 recutils, GNU recutils manual}). As an example, the command shows the command
15606 line and PID of the client that triggered the build of a Perl package:
15609 $ sudo guix processes | \
15610 recsel -p ClientPID,ClientCommand -e 'LockHeld ~ "perl"'
15612 ClientCommand: cuirass --cache-directory /var/cache/cuirass @dots{}
15615 Additional options are listed below.
15618 @item --format=@var{format}
15619 @itemx -f @var{format}
15620 Produce output in the specified @var{format}, one of:
15624 The default option. It outputs a set of Session recutils records
15625 that include each @code{ChildProcess} as a field.
15628 Normalize the output records into record sets (@pxref{Record Sets,,,
15629 recutils, GNU recutils manual}). Normalizing into record sets allows
15630 joins across record types. The example below lists the PID of each
15631 @code{ChildProcess} and the associated PID for @code{Session} that
15632 spawned the @code{ChildProcess} where the @code{Session} was started
15633 using @command{guix build}.
15636 $ guix processes --format=normalized | \
15640 -p Session.PID,PID \
15641 -e 'Session.ClientCommand ~ "guix build"'
15654 @node Foreign Architectures
15655 @chapter Foreign Architectures
15657 You can target computers of different CPU architectures when producing
15658 packages (@pxref{Invoking guix package}), packs (@pxref{Invoking guix
15659 pack}) or full systems (@pxref{Invoking guix system}).
15661 GNU Guix supports two distinct mechanisms to target foreign
15667 @uref{https://en.wikipedia.org/wiki/Cross_compiler,cross-compilation}
15670 The native building mechanism which consists in building using the CPU
15671 instruction set of the foreign system you are targeting. It often
15672 requires emulation, using the QEMU program for instance.
15676 * Cross-Compilation:: Cross-compiling for another architecture.
15677 * Native Builds:: Targeting another architecture through native builds.
15680 @node Cross-Compilation
15681 @section Cross-Compilation
15683 @cindex foreign architectures
15684 The commands supporting cross-compilation are proposing the
15685 @option{--list-targets} and @option{--target} options.
15687 The @option{--list-targets} option lists all the supported targets that
15688 can be passed as an argument to @option{--target}.
15691 $ guix build --list-targets
15692 The available targets are:
15694 - aarch64-linux-gnu
15695 - arm-linux-gnueabihf
15699 - mips64el-linux-gnu
15700 - powerpc-linux-gnu
15701 - powerpc64le-linux-gnu
15702 - riscv64-linux-gnu
15704 - x86_64-w64-mingw32
15707 Targets are specified as GNU triplets (@pxref{Specifying Target
15708 Triplets, GNU configuration triplets,, autoconf, Autoconf}).
15710 Those triplets are passed to GCC and the other underlying compilers
15711 possibly involved when building a package, a system image or any other
15715 $ guix build --target=aarch64-linux-gnu hello
15716 /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12
15718 $ file /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12/bin/hello
15719 /gnu/store/9926by9qrxa91ijkhw9ndgwp4bn24g9h-hello-2.12/bin/hello: ELF
15720 64-bit LSB executable, ARM aarch64 @dots{}
15723 The major benefit of cross-compilation is that there are no performance
15724 penaly compared to emulation using QEMU. There are however higher risks
15725 that some packages fail to cross-compile because few users are using
15726 this mechanism extensively.
15728 @node Native Builds
15729 @section Native Builds
15731 The commands that support impersonating a specific system have the
15732 @option{--list-systems} and @option{--system} options.
15734 The @option{--list-systems} option lists all the supported systems that
15735 can be passed as an argument to @option{--system}.
15738 $ guix build --list-systems
15739 The available systems are:
15741 - x86_64-linux [current]
15748 - powerpc64le-linux
15751 $ guix build --system=i686-linux hello
15752 /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12
15754 $ file /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12/bin/hello
15755 /gnu/store/cc0km35s8x2z4pmwkrqqjx46i8b1i3gm-hello-2.12/bin/hello: ELF
15756 32-bit LSB executable, Intel 80386 @dots{}
15759 In the above example, the current system is @var{x86_64-linux}. The
15760 @var{hello} package is however built for the @var{i686-linux} system.
15762 This is possible because the @var{i686} CPU instruction set is a subset
15763 of the @var{x86_64}, hence @var{i686} targeting binaries can be run on
15766 Still in the context of the previous example, if picking the
15767 @var{aarch64-linux} system and the @command{guix build
15768 --system=aarch64-linux hello} has to build some derivations, an extra
15769 step might be needed.
15771 The @var{aarch64-linux} targeting binaries cannot directly be run on a
15772 @var{x86_64-linux} system. An emulation layer is requested. The GNU
15773 Guix daemon can take advantage of the Linux kernel
15774 @uref{https://en.wikipedia.org/wiki/Binfmt_misc,binfmt_misc} mechanism
15775 for that. In short, the Linux kernel can defer the execution of a
15776 binary targeting a foreign platform, here @var{aarch64-linux}, to a
15777 userspace program, usually an emulator.
15779 There is a service that registers QEMU as a backend for the
15780 @code{binfmt_misc} mechanism (@pxref{Virtualization Services,
15781 @code{qemu-binfmt-service-type}}). On Debian based foreign
15782 distributions, the alternative would be the @code{qemu-user-static}
15785 If the @code{binfmt_misc} mechanism is not setup correctly, the building
15786 will fail this way:
15789 $ guix build --system=armhf-linux hello --check
15791 @ unsupported-platform /gnu/store/jjn969pijv7hff62025yxpfmc8zy0aq0-hello-2.12.drv aarch64-linux
15792 while setting up the build environment: a `aarch64-linux' is required to
15793 build `/gnu/store/jjn969pijv7hff62025yxpfmc8zy0aq0-hello-2.12.drv', but
15794 I am a `x86_64-linux'@dots{}
15797 whereas, with the @code{binfmt_misc} mechanism correctly linked with
15798 QEMU, one can expect to see:
15801 $ guix build --system=armhf-linux hello --check
15802 /gnu/store/13xz4nghg39wpymivlwghy08yzj97hlj-hello-2.12
15805 The main advantage of native building compared to cross-compiling, is
15806 that more packages are likely to build correctly. However it comes at a
15807 price: compilation backed by QEMU is @emph{way slower} than
15808 cross-compilation, because every instruction needs to be emulated.
15810 The availability of substitutes for the architecture targeted by the
15811 @code{--system} option can mitigate this problem. An other way to work
15812 around it is to install GNU Guix on a machine which CPU is supporting
15813 the targeted instruction set, an set it up as an offload machine
15814 (@pxref{Daemon Offload Setup}).
15816 @node System Configuration
15817 @chapter System Configuration
15819 @cindex system configuration
15820 Guix System supports a consistent whole-system configuration
15821 mechanism. By that we mean that all aspects of the global system
15822 configuration---such as the available system services, timezone and
15823 locale settings, user accounts---are declared in a single place. Such
15824 a @dfn{system configuration} can be @dfn{instantiated}---i.e., effected.
15826 One of the advantages of putting all the system configuration under the
15827 control of Guix is that it supports transactional system upgrades, and
15828 makes it possible to roll back to a previous system instantiation,
15829 should something go wrong with the new one (@pxref{Features}). Another
15830 advantage is that it makes it easy to replicate the exact same configuration
15831 across different machines, or at different points in time, without
15832 having to resort to additional administration tools layered on top of
15833 the own tools of the system.
15834 @c Yes, we're talking of Puppet, Chef, & co. here. ↑
15836 This section describes this mechanism. First we focus on the system
15837 administrator's viewpoint---explaining how the system is configured and
15838 instantiated. Then we show how this mechanism can be extended, for
15839 instance to support new system services.
15842 * Using the Configuration System:: Customizing your GNU system.
15843 * operating-system Reference:: Detail of operating-system declarations.
15844 * File Systems:: Configuring file system mounts.
15845 * Mapped Devices:: Block device extra processing.
15846 * Swap Space:: Backing RAM with disk space.
15847 * User Accounts:: Specifying user accounts.
15848 * Keyboard Layout:: How the system interprets key strokes.
15849 * Locales:: Language and cultural convention settings.
15850 * Services:: Specifying system services.
15851 * Setuid Programs:: Programs running with elevated privileges.
15852 * X.509 Certificates:: Authenticating HTTPS servers.
15853 * Name Service Switch:: Configuring libc's name service switch.
15854 * Initial RAM Disk:: Linux-Libre bootstrapping.
15855 * Bootloader Configuration:: Configuring the boot loader.
15856 * Invoking guix system:: Instantiating a system configuration.
15857 * Invoking guix deploy:: Deploying a system configuration to a remote host.
15858 * Running Guix in a VM:: How to run Guix System in a virtual machine.
15859 * Defining Services:: Adding new service definitions.
15862 @node Using the Configuration System
15863 @section Using the Configuration System
15865 The operating system is configured by providing an
15866 @code{operating-system} declaration in a file that can then be passed to
15867 the @command{guix system} command (@pxref{Invoking guix system}). A
15868 simple setup, with the default system services, the default Linux-Libre
15869 kernel, initial RAM disk, and boot loader looks like this:
15871 @findex operating-system
15873 @include os-config-bare-bones.texi
15876 This example should be self-describing. Some of the fields defined
15877 above, such as @code{host-name} and @code{bootloader}, are mandatory.
15878 Others, such as @code{packages} and @code{services}, can be omitted, in
15879 which case they get a default value.
15881 Below we discuss the effect of some of the most important fields
15882 (@pxref{operating-system Reference}, for details about all the available
15883 fields), and how to @dfn{instantiate} the operating system using
15884 @command{guix system}.
15886 @unnumberedsubsec Bootloader
15888 @cindex legacy boot, on Intel machines
15889 @cindex BIOS boot, on Intel machines
15892 The @code{bootloader} field describes the method that will be used to boot
15893 your system. Machines based on Intel processors can boot in ``legacy'' BIOS
15894 mode, as in the example above. However, more recent machines rely instead on
15895 the @dfn{Unified Extensible Firmware Interface} (UEFI) to boot. In that case,
15896 the @code{bootloader} field should contain something along these lines:
15899 (bootloader-configuration
15900 (bootloader grub-efi-bootloader)
15901 (targets '("/boot/efi")))
15904 @xref{Bootloader Configuration}, for more information on the available
15905 configuration options.
15907 @unnumberedsubsec Globally-Visible Packages
15909 @vindex %base-packages
15910 The @code{packages} field lists packages that will be globally visible
15911 on the system, for all user accounts---i.e., in every user's @env{PATH}
15912 environment variable---in addition to the per-user profiles
15913 (@pxref{Invoking guix package}). The @code{%base-packages} variable
15914 provides all the tools one would expect for basic user and administrator
15915 tasks---including the GNU Core Utilities, the GNU Networking Utilities,
15916 the @command{mg} lightweight text editor, @command{find}, @command{grep},
15917 etc. The example above adds GNU@tie{}Screen to those,
15918 taken from the @code{(gnu packages screen)}
15919 module (@pxref{Package Modules}). The
15920 @code{(list package output)} syntax can be used to add a specific output
15924 (use-modules (gnu packages))
15925 (use-modules (gnu packages dns))
15929 (packages (cons (list isc-bind "utils")
15933 @findex specification->package
15934 Referring to packages by variable name, like @code{isc-bind} above, has
15935 the advantage of being unambiguous; it also allows typos and such to be
15936 diagnosed right away as ``unbound variables''. The downside is that one
15937 needs to know which module defines which package, and to augment the
15938 @code{use-package-modules} line accordingly. To avoid that, one can use
15939 the @code{specification->package} procedure of the @code{(gnu packages)}
15940 module, which returns the best package for a given name or name and
15944 (use-modules (gnu packages))
15948 (packages (append (map specification->package
15949 '("tcpdump" "htop" "gnupg@@2.0"))
15953 @unnumberedsubsec System Services
15956 @vindex %base-services
15957 The @code{services} field lists @dfn{system services} to be made
15958 available when the system starts (@pxref{Services}).
15959 The @code{operating-system} declaration above specifies that, in
15960 addition to the basic services, we want the OpenSSH secure shell
15961 daemon listening on port 2222 (@pxref{Networking Services,
15962 @code{openssh-service-type}}). Under the hood,
15963 @code{openssh-service-type} arranges so that @command{sshd} is started with the
15964 right command-line options, possibly with supporting configuration files
15965 generated as needed (@pxref{Defining Services}).
15967 @cindex customization, of services
15968 @findex modify-services
15969 Occasionally, instead of using the base services as is, you will want to
15970 customize them. To do this, use @code{modify-services} (@pxref{Service
15971 Reference, @code{modify-services}}) to modify the list.
15973 @anchor{auto-login to TTY} For example, suppose you want to modify
15974 @code{guix-daemon} and Mingetty (the console log-in) in the
15975 @code{%base-services} list (@pxref{Base Services,
15976 @code{%base-services}}). To do that, you can write the following in
15977 your operating system declaration:
15980 (define %my-services
15981 ;; My very own list of services.
15982 (modify-services %base-services
15983 (guix-service-type config =>
15984 (guix-configuration
15986 ;; Fetch substitutes from example.org.
15988 (list "https://example.org/guix"
15989 "https://ci.guix.gnu.org"))))
15990 (mingetty-service-type config =>
15991 (mingetty-configuration
15993 ;; Automatically log in as "guest".
15994 (auto-login "guest")))))
15998 (services %my-services))
16001 This changes the configuration---i.e., the service parameters---of the
16002 @code{guix-service-type} instance, and that of all the
16003 @code{mingetty-service-type} instances in the @code{%base-services} list
16004 (@pxref{Auto-Login to a Specific TTY, see the cookbook for how to
16005 auto-login one user to a specific TTY,, guix-cookbook, GNU Guix Cookbook})).
16006 Observe how this is accomplished: first, we arrange for the original
16007 configuration to be bound to the identifier @code{config} in the
16008 @var{body}, and then we write the @var{body} so that it evaluates to the
16009 desired configuration. In particular, notice how we use @code{inherit}
16010 to create a new configuration which has the same values as the old
16011 configuration, but with a few modifications.
16013 @cindex encrypted disk
16014 The configuration for a typical ``desktop'' usage, with an encrypted
16015 root partition, a swap file on the root partition, the X11 display
16016 server, GNOME and Xfce (users can choose which of these desktop
16017 environments to use at the log-in screen by pressing @kbd{F1}), network
16018 management, power management, and more, would look like this:
16021 @include os-config-desktop.texi
16024 A graphical system with a choice of lightweight window managers
16025 instead of full-blown desktop environments would look like this:
16028 @include os-config-lightweight-desktop.texi
16031 This example refers to the @file{/boot/efi} file system by its UUID,
16032 @code{1234-ABCD}. Replace this UUID with the right UUID on your system,
16033 as returned by the @command{blkid} command.
16035 @xref{Desktop Services}, for the exact list of services provided by
16036 @code{%desktop-services}. @xref{X.509 Certificates}, for background
16037 information about the @code{nss-certs} package that is used here.
16039 Again, @code{%desktop-services} is just a list of service objects. If
16040 you want to remove services from there, you can do so using the
16041 procedures for list filtering (@pxref{SRFI-1 Filtering and
16042 Partitioning,,, guile, GNU Guile Reference Manual}). For instance, the
16043 following expression returns a list that contains all the services in
16044 @code{%desktop-services} minus the Avahi service:
16047 (remove (lambda (service)
16048 (eq? (service-kind service) avahi-service-type))
16052 Alternatively, the @code{modify-services} macro can be used:
16055 (modify-services %desktop-services
16056 (delete avahi-service-type))
16060 @unnumberedsubsec Instantiating the System
16062 Assuming the @code{operating-system} declaration
16063 is stored in the @file{my-system-config.scm}
16064 file, the @command{guix system reconfigure my-system-config.scm} command
16065 instantiates that configuration, and makes it the default GRUB boot
16066 entry (@pxref{Invoking guix system}).
16069 We recommend that you keep this @file{my-system-config.scm} file safe
16070 and under version control to easily track changes to your configuration.
16073 The normal way to change the system configuration is by updating this
16074 file and re-running @command{guix system reconfigure}. One should never
16075 have to touch files in @file{/etc} or to run commands that modify the
16076 system state such as @command{useradd} or @command{grub-install}. In
16077 fact, you must avoid that since that would not only void your warranty
16078 but also prevent you from rolling back to previous versions of your
16079 system, should you ever need to.
16081 @cindex roll-back, of the operating system
16082 Speaking of roll-back, each time you run @command{guix system
16083 reconfigure}, a new @dfn{generation} of the system is created---without
16084 modifying or deleting previous generations. Old system generations get
16085 an entry in the bootloader boot menu, allowing you to boot them in case
16086 something went wrong with the latest generation. Reassuring, no? The
16087 @command{guix system list-generations} command lists the system
16088 generations available on disk. It is also possible to roll back the
16089 system via the commands @command{guix system roll-back} and
16090 @command{guix system switch-generation}.
16092 Although the @command{guix system reconfigure} command will not modify
16093 previous generations, you must take care when the current generation is not
16094 the latest (e.g., after invoking @command{guix system roll-back}), since
16095 the operation might overwrite a later generation (@pxref{Invoking guix
16098 @unnumberedsubsec The Programming Interface
16100 At the Scheme level, the bulk of an @code{operating-system} declaration
16101 is instantiated with the following monadic procedure (@pxref{The Store
16104 @deffn {Monadic Procedure} operating-system-derivation os
16105 Return a derivation that builds @var{os}, an @code{operating-system}
16106 object (@pxref{Derivations}).
16108 The output of the derivation is a single directory that refers to all
16109 the packages, configuration files, and other supporting files needed to
16110 instantiate @var{os}.
16113 This procedure is provided by the @code{(gnu system)} module. Along
16114 with @code{(gnu services)} (@pxref{Services}), this module contains the
16115 guts of Guix System. Make sure to visit it!
16118 @node operating-system Reference
16119 @section @code{operating-system} Reference
16121 This section summarizes all the options available in
16122 @code{operating-system} declarations (@pxref{Using the Configuration
16125 @deftp {Data Type} operating-system
16126 This is the data type representing an operating system configuration.
16127 By that, we mean all the global system configuration, not per-user
16128 configuration (@pxref{Using the Configuration System}).
16131 @item @code{kernel} (default: @code{linux-libre})
16132 The package object of the operating system kernel to
16133 use@footnote{Currently only the Linux-libre kernel is fully supported.
16134 Using GNU@tie{}mach with the GNU@tie{}Hurd is experimental and only
16135 available when building a virtual machine disk image.}.
16138 @item @code{hurd} (default: @code{#f})
16139 The package object of the Hurd to be started by the kernel. When this
16140 field is set, produce a GNU/Hurd operating system. In that case,
16141 @code{kernel} must also be set to the @code{gnumach} package---the
16142 microkernel the Hurd runs on.
16145 This feature is experimental and only supported for disk images.
16148 @item @code{kernel-loadable-modules} (default: '())
16149 A list of objects (usually packages) to collect loadable kernel modules
16150 from--e.g. @code{(list ddcci-driver-linux)}.
16152 @item @code{kernel-arguments} (default: @code{%default-kernel-arguments})
16153 List of strings or gexps representing additional arguments to pass on
16154 the command-line of the kernel---e.g., @code{("console=ttyS0")}.
16156 @item @code{bootloader}
16157 The system bootloader configuration object. @xref{Bootloader Configuration}.
16160 This is the label (a string) as it appears in the bootloader's menu entry.
16161 The default label includes the kernel name and version.
16163 @item @code{keyboard-layout} (default: @code{#f})
16164 This field specifies the keyboard layout to use in the console. It can be
16165 either @code{#f}, in which case the default keyboard layout is used (usually
16166 US English), or a @code{<keyboard-layout>} record. @xref{Keyboard Layout},
16167 for more information.
16169 This keyboard layout is in effect as soon as the kernel has booted. For
16170 instance, it is the keyboard layout in effect when you type a passphrase if
16171 your root file system is on a @code{luks-device-mapping} mapped device
16172 (@pxref{Mapped Devices}).
16175 This does @emph{not} specify the keyboard layout used by the bootloader, nor
16176 that used by the graphical display server. @xref{Bootloader Configuration},
16177 for information on how to specify the bootloader's keyboard layout. @xref{X
16178 Window}, for information on how to specify the keyboard layout used by the X
16182 @item @code{initrd-modules} (default: @code{%base-initrd-modules})
16184 @cindex initial RAM disk
16185 The list of Linux kernel modules that need to be available in the
16186 initial RAM disk. @xref{Initial RAM Disk}.
16188 @item @code{initrd} (default: @code{base-initrd})
16189 A procedure that returns an initial RAM disk for the Linux
16190 kernel. This field is provided to support low-level customization and
16191 should rarely be needed for casual use. @xref{Initial RAM Disk}.
16193 @item @code{firmware} (default: @code{%base-firmware})
16195 List of firmware packages loadable by the operating system kernel.
16197 The default includes firmware needed for Atheros- and Broadcom-based
16198 WiFi devices (Linux-libre modules @code{ath9k} and @code{b43-open},
16199 respectively). @xref{Hardware Considerations}, for more info on
16200 supported hardware.
16202 @item @code{host-name}
16205 @item @code{hosts-file}
16207 A file-like object (@pxref{G-Expressions, file-like objects}) for use as
16208 @file{/etc/hosts} (@pxref{Host Names,,, libc, The GNU C Library
16209 Reference Manual}). The default is a file with entries for
16210 @code{localhost} and @var{host-name}.
16212 @item @code{mapped-devices} (default: @code{'()})
16213 A list of mapped devices. @xref{Mapped Devices}.
16215 @item @code{file-systems}
16216 A list of file systems. @xref{File Systems}.
16218 @item @code{swap-devices} (default: @code{'()})
16219 @cindex swap devices
16220 A list of swap spaces. @xref{Swap Space}.
16222 @item @code{users} (default: @code{%base-user-accounts})
16223 @itemx @code{groups} (default: @code{%base-groups})
16224 List of user accounts and groups. @xref{User Accounts}.
16226 If the @code{users} list lacks a user account with UID@tie{}0, a
16227 ``root'' account with UID@tie{}0 is automatically added.
16229 @item @code{skeletons} (default: @code{(default-skeletons)})
16230 A list of target file name/file-like object tuples (@pxref{G-Expressions,
16231 file-like objects}). These are the skeleton files that will be added to
16232 the home directory of newly-created user accounts.
16234 For instance, a valid value may look like this:
16237 `((".bashrc" ,(plain-file "bashrc" "echo Hello\n"))
16238 (".guile" ,(plain-file "guile"
16239 "(use-modules (ice-9 readline))
16240 (activate-readline)")))
16243 @item @code{issue} (default: @code{%default-issue})
16244 A string denoting the contents of the @file{/etc/issue} file, which is
16245 displayed when users log in on a text console.
16247 @item @code{packages} (default: @code{%base-packages})
16248 A list of packages to be installed in the global profile, which is accessible
16249 at @file{/run/current-system/profile}. Each element is either a package
16250 variable or a package/output tuple. Here's a simple example of both:
16253 (cons* git ; the default "out" output
16254 (list git "send-email") ; another output of git
16255 %base-packages) ; the default set
16258 The default set includes core utilities and it is good practice to
16259 install non-core utilities in user profiles (@pxref{Invoking guix
16262 @item @code{timezone}
16263 A timezone identifying string---e.g., @code{"Europe/Paris"}.
16265 You can run the @command{tzselect} command to find out which timezone
16266 string corresponds to your region. Choosing an invalid timezone name
16267 causes @command{guix system} to fail.
16269 @item @code{locale} (default: @code{"en_US.utf8"})
16270 The name of the default locale (@pxref{Locale Names,,, libc, The GNU C
16271 Library Reference Manual}). @xref{Locales}, for more information.
16273 @item @code{locale-definitions} (default: @code{%default-locale-definitions})
16274 The list of locale definitions to be compiled and that may be used at
16275 run time. @xref{Locales}.
16277 @item @code{locale-libcs} (default: @code{(list @var{glibc})})
16278 The list of GNU@tie{}libc packages whose locale data and tools are used
16279 to build the locale definitions. @xref{Locales}, for compatibility
16280 considerations that justify this option.
16282 @item @code{name-service-switch} (default: @code{%default-nss})
16283 Configuration of the libc name service switch (NSS)---a
16284 @code{<name-service-switch>} object. @xref{Name Service Switch}, for
16287 @item @code{services} (default: @code{%base-services})
16288 A list of service objects denoting system services. @xref{Services}.
16290 @cindex essential services
16291 @item @code{essential-services} (default: ...)
16292 The list of ``essential services''---i.e., things like instances of
16293 @code{system-service-type} and @code{host-name-service-type} (@pxref{Service
16294 Reference}), which are derived from the operating system definition itself.
16295 As a user you should @emph{never} need to touch this field.
16297 @item @code{pam-services} (default: @code{(base-pam-services)})
16299 @cindex pluggable authentication modules
16300 Linux @dfn{pluggable authentication module} (PAM) services.
16301 @c FIXME: Add xref to PAM services section.
16303 @item @code{setuid-programs} (default: @code{%setuid-programs})
16304 List of @code{<setuid-program>}. @xref{Setuid Programs}, for more
16307 @item @code{sudoers-file} (default: @code{%sudoers-specification})
16308 @cindex sudoers file
16309 The contents of the @file{/etc/sudoers} file as a file-like object
16310 (@pxref{G-Expressions, @code{local-file} and @code{plain-file}}).
16312 This file specifies which users can use the @command{sudo} command, what
16313 they are allowed to do, and what privileges they may gain. The default
16314 is that only @code{root} and members of the @code{wheel} group may use
16319 @deffn {Scheme Syntax} this-operating-system
16320 When used in the @emph{lexical scope} of an operating system field definition,
16321 this identifier resolves to the operating system being defined.
16323 The example below shows how to refer to the operating system being defined in
16324 the definition of the @code{label} field:
16327 (use-modules (gnu) (guix))
16331 (label (package-full-name
16332 (operating-system-kernel this-operating-system))))
16335 It is an error to refer to @code{this-operating-system} outside an operating
16342 @section File Systems
16344 The list of file systems to be mounted is specified in the
16345 @code{file-systems} field of the operating system declaration
16346 (@pxref{Using the Configuration System}). Each file system is declared
16347 using the @code{file-system} form, like this:
16351 (mount-point "/home")
16352 (device "/dev/sda3")
16356 As usual, some of the fields are mandatory---those shown in the example
16357 above---while others can be omitted. These are described below.
16359 @deftp {Data Type} file-system
16360 Objects of this type represent file systems to be mounted. They
16361 contain the following members:
16365 This is a string specifying the type of the file system---e.g.,
16368 @item @code{mount-point}
16369 This designates the place where the file system is to be mounted.
16371 @item @code{device}
16372 This names the ``source'' of the file system. It can be one of three
16373 things: a file system label, a file system UUID, or the name of a
16374 @file{/dev} node. Labels and UUIDs offer a way to refer to file
16375 systems without having to hard-code their actual device
16376 name@footnote{Note that, while it is tempting to use
16377 @file{/dev/disk/by-uuid} and similar device names to achieve the same
16378 result, this is not recommended: These special device nodes are created
16379 by the udev daemon and may be unavailable at the time the device is
16382 @findex file-system-label
16383 File system labels are created using the @code{file-system-label}
16384 procedure, UUIDs are created using @code{uuid}, and @file{/dev} node are
16385 plain strings. Here's an example of a file system referred to by its
16386 label, as shown by the @command{e2label} command:
16390 (mount-point "/home")
16392 (device (file-system-label "my-home")))
16396 UUIDs are converted from their string representation (as shown by the
16397 @command{tune2fs -l} command) using the @code{uuid} form@footnote{The
16398 @code{uuid} form expects 16-byte UUIDs as defined in
16399 @uref{https://tools.ietf.org/html/rfc4122, RFC@tie{}4122}. This is the
16400 form of UUID used by the ext2 family of file systems and others, but it
16401 is different from ``UUIDs'' found in FAT file systems, for instance.},
16406 (mount-point "/home")
16408 (device (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
16411 When the source of a file system is a mapped device (@pxref{Mapped
16412 Devices}), its @code{device} field @emph{must} refer to the mapped
16413 device name---e.g., @file{"/dev/mapper/root-partition"}.
16414 This is required so that
16415 the system knows that mounting the file system depends on having the
16416 corresponding device mapping established.
16418 @item @code{flags} (default: @code{'()})
16419 This is a list of symbols denoting mount flags. Recognized flags
16420 include @code{read-only}, @code{bind-mount}, @code{no-dev} (disallow
16421 access to special files), @code{no-suid} (ignore setuid and setgid
16422 bits), @code{no-atime} (do not update file access times),
16423 @code{strict-atime} (update file access time), @code{lazy-time} (only
16424 update time on the in-memory version of the file inode),
16425 @code{no-exec} (disallow program execution), and @code{shared} (make the
16427 @xref{Mount-Unmount-Remount,,, libc, The GNU C Library Reference
16428 Manual}, for more information on these flags.
16430 @item @code{options} (default: @code{#f})
16431 This is either @code{#f}, or a string denoting mount options passed to
16432 the file system driver. @xref{Mount-Unmount-Remount,,, libc, The GNU C
16433 Library Reference Manual}, for details.
16435 Run @command{man 8 mount} for options for various file systems, but
16436 beware that what it lists as file-system-independent ``mount options'' are
16437 in fact flags, and belong in the @code{flags} field described above.
16439 The @code{file-system-options->alist} and @code{alist->file-system-options}
16440 procedures from @code{(gnu system file-systems)} can be used to convert
16441 file system options given as an association list to the string
16442 representation, and vice-versa.
16444 @item @code{mount?} (default: @code{#t})
16445 This value indicates whether to automatically mount the file system when
16446 the system is brought up. When set to @code{#f}, the file system gets
16447 an entry in @file{/etc/fstab} (read by the @command{mount} command) but
16448 is not automatically mounted.
16450 @item @code{needed-for-boot?} (default: @code{#f})
16451 This Boolean value indicates whether the file system is needed when
16452 booting. If that is true, then the file system is mounted when the
16453 initial RAM disk (initrd) is loaded. This is always the case, for
16454 instance, for the root file system.
16456 @item @code{check?} (default: @code{#t})
16457 This Boolean indicates whether the file system should be checked for
16458 errors before being mounted. How and when this happens can be further
16459 adjusted with the following options.
16461 @item @code{skip-check-if-clean?} (default: @code{#t})
16462 When true, this Boolean indicates that a file system check triggered
16463 by @code{check?} may exit early if the file system is marked as
16464 ``clean'', meaning that it was previously correctly unmounted and
16465 should not contain errors.
16467 Setting this to false will always force a full consistency check when
16468 @code{check?} is true. This may take a very long time and is not
16469 recommended on healthy systems---in fact, it may reduce reliability!
16471 Conversely, some primitive file systems like @code{fat} do not keep
16472 track of clean shutdowns and will perform a full scan regardless of the
16473 value of this option.
16475 @item @code{repair} (default: @code{'preen})
16476 When @code{check?} finds errors, it can (try to) repair them and
16477 continue booting. This option controls when and how to do so.
16479 If false, try not to modify the file system at all. Checking certain
16480 file systems like @code{jfs} may still write to the device to replay
16481 the journal. No repairs will be attempted.
16483 If @code{#t}, try to repair any errors found and assume ``yes'' to
16484 all questions. This will fix the most errors, but may be risky.
16486 If @code{'preen}, repair only errors that are safe to fix without
16487 human interaction. What that means is left up to the developers of
16488 each file system and may be equivalent to ``none'' or ``all''.
16490 @item @code{create-mount-point?} (default: @code{#f})
16491 When true, the mount point is created if it does not exist yet.
16493 @item @code{mount-may-fail?} (default: @code{#f})
16494 When true, this indicates that mounting this file system can fail but
16495 that should not be considered an error. This is useful in unusual
16496 cases; an example of this is @code{efivarfs}, a file system that can
16497 only be mounted on EFI/UEFI systems.
16499 @item @code{dependencies} (default: @code{'()})
16500 This is a list of @code{<file-system>} or @code{<mapped-device>} objects
16501 representing file systems that must be mounted or mapped devices that
16502 must be opened before (and unmounted or closed after) this one.
16504 As an example, consider a hierarchy of mounts: @file{/sys/fs/cgroup} is
16505 a dependency of @file{/sys/fs/cgroup/cpu} and
16506 @file{/sys/fs/cgroup/memory}.
16508 Another example is a file system that depends on a mapped device, for
16509 example for an encrypted partition (@pxref{Mapped Devices}).
16513 @deffn {Scheme Procedure} file-system-label @var{str}
16514 This procedure returns an opaque file system label from @var{str}, a
16518 (file-system-label "home")
16519 @result{} #<file-system-label "home">
16522 File system labels are used to refer to file systems by label rather
16523 than by device name. See above for examples.
16526 The @code{(gnu system file-systems)} exports the following useful
16529 @defvr {Scheme Variable} %base-file-systems
16530 These are essential file systems that are required on normal systems,
16531 such as @code{%pseudo-terminal-file-system} and @code{%immutable-store} (see
16532 below). Operating system declarations should always contain at least
16536 @defvr {Scheme Variable} %pseudo-terminal-file-system
16537 This is the file system to be mounted as @file{/dev/pts}. It supports
16538 @dfn{pseudo-terminals} created @i{via} @code{openpty} and similar
16539 functions (@pxref{Pseudo-Terminals,,, libc, The GNU C Library Reference
16540 Manual}). Pseudo-terminals are used by terminal emulators such as
16544 @defvr {Scheme Variable} %shared-memory-file-system
16545 This file system is mounted as @file{/dev/shm} and is used to support
16546 memory sharing across processes (@pxref{Memory-mapped I/O,
16547 @code{shm_open},, libc, The GNU C Library Reference Manual}).
16550 @defvr {Scheme Variable} %immutable-store
16551 This file system performs a read-only ``bind mount'' of
16552 @file{/gnu/store}, making it read-only for all the users including
16553 @code{root}. This prevents against accidental modification by software
16554 running as @code{root} or by system administrators.
16556 The daemon itself is still able to write to the store: it remounts it
16557 read-write in its own ``name space.''
16560 @defvr {Scheme Variable} %binary-format-file-system
16561 The @code{binfmt_misc} file system, which allows handling of arbitrary
16562 executable file types to be delegated to user space. This requires the
16563 @code{binfmt.ko} kernel module to be loaded.
16566 @defvr {Scheme Variable} %fuse-control-file-system
16567 The @code{fusectl} file system, which allows unprivileged users to mount
16568 and unmount user-space FUSE file systems. This requires the
16569 @code{fuse.ko} kernel module to be loaded.
16572 The @code{(gnu system uuid)} module provides tools to deal with file
16573 system ``unique identifiers'' (UUIDs).
16575 @deffn {Scheme Procedure} uuid @var{str} [@var{type}]
16576 Return an opaque UUID (unique identifier) object of the given @var{type}
16577 (a symbol) by parsing @var{str} (a string):
16580 (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")
16581 @result{} #<<uuid> type: dce bv: @dots{}>
16583 (uuid "1234-ABCD" 'fat)
16584 @result{} #<<uuid> type: fat bv: @dots{}>
16587 @var{type} may be one of @code{dce}, @code{iso9660}, @code{fat},
16588 @code{ntfs}, or one of the commonly found synonyms for these.
16590 UUIDs are another way to unambiguously refer to file systems in
16591 operating system configuration. See the examples above.
16595 @node Btrfs file system
16596 @subsection Btrfs file system
16598 The Btrfs has special features, such as subvolumes, that merit being
16599 explained in more details. The following section attempts to cover
16600 basic as well as complex uses of a Btrfs file system with the Guix
16603 In its simplest usage, a Btrfs file system can be described, for
16608 (mount-point "/home")
16610 (device (file-system-label "my-home")))
16613 The example below is more complex, as it makes use of a Btrfs
16614 subvolume, named @code{rootfs}. The parent Btrfs file system is labeled
16615 @code{my-btrfs-pool}, and is located on an encrypted device (hence the
16616 dependency on @code{mapped-devices}):
16620 (device (file-system-label "my-btrfs-pool"))
16623 (options "subvol=rootfs")
16624 (dependencies mapped-devices))
16627 Some bootloaders, for example GRUB, only mount a Btrfs partition at its
16628 top level during the early boot, and rely on their configuration to
16629 refer to the correct subvolume path within that top level. The
16630 bootloaders operating in this way typically produce their configuration
16631 on a running system where the Btrfs partitions are already mounted and
16632 where the subvolume information is readily available. As an example,
16633 @command{grub-mkconfig}, the configuration generator command shipped
16634 with GRUB, reads @file{/proc/self/mountinfo} to determine the top-level
16635 path of a subvolume.
16637 The Guix System produces a bootloader configuration using the operating
16638 system configuration as its sole input; it is therefore necessary to
16639 extract the subvolume name on which @file{/gnu/store} lives (if any)
16640 from that operating system configuration. To better illustrate,
16641 consider a subvolume named 'rootfs' which contains the root file system
16642 data. In such situation, the GRUB bootloader would only see the top
16643 level of the root Btrfs partition, e.g.:
16647 ├── rootfs (subvolume directory)
16648 ├── gnu (normal directory)
16649 ├── store (normal directory)
16653 Thus, the subvolume name must be prepended to the @file{/gnu/store} path
16654 of the kernel, initrd binaries and any other files referred to in the
16655 GRUB configuration that must be found during the early boot.
16657 The next example shows a nested hierarchy of subvolumes and
16662 ├── rootfs (subvolume)
16663 ├── gnu (normal directory)
16664 ├── store (subvolume)
16668 This scenario would work without mounting the 'store' subvolume.
16669 Mounting 'rootfs' is sufficient, since the subvolume name matches its
16670 intended mount point in the file system hierarchy. Alternatively, the
16671 'store' subvolume could be referred to by setting the @code{subvol}
16672 option to either @code{/rootfs/gnu/store} or @code{rootfs/gnu/store}.
16674 Finally, a more contrived example of nested subvolumes:
16678 ├── root-snapshots (subvolume)
16679 ├── root-current (subvolume)
16680 ├── guix-store (subvolume)
16684 Here, the 'guix-store' subvolume doesn't match its intended mount point,
16685 so it is necessary to mount it. The subvolume must be fully specified,
16686 by passing its file name to the @code{subvol} option. To illustrate,
16687 the 'guix-store' subvolume could be mounted on @file{/gnu/store} by using
16688 a file system declaration such as:
16692 (device (file-system-label "btrfs-pool-1"))
16693 (mount-point "/gnu/store")
16695 (options "subvol=root-snapshots/root-current/guix-store,\
16696 compress-force=zstd,space_cache=v2"))
16699 @node Mapped Devices
16700 @section Mapped Devices
16702 @cindex device mapping
16703 @cindex mapped devices
16704 The Linux kernel has a notion of @dfn{device mapping}: a block device,
16705 such as a hard disk partition, can be @dfn{mapped} into another device,
16706 usually in @code{/dev/mapper/},
16707 with additional processing over the data that flows through
16708 it@footnote{Note that the GNU@tie{}Hurd makes no difference between the
16709 concept of a ``mapped device'' and that of a file system: both boil down
16710 to @emph{translating} input/output operations made on a file to
16711 operations on its backing store. Thus, the Hurd implements mapped
16712 devices, like file systems, using the generic @dfn{translator} mechanism
16713 (@pxref{Translators,,, hurd, The GNU Hurd Reference Manual}).}. A
16714 typical example is encryption device mapping: all writes to the mapped
16715 device are encrypted, and all reads are deciphered, transparently.
16716 Guix extends this notion by considering any device or set of devices that
16717 are @dfn{transformed} in some way to create a new device; for instance,
16718 RAID devices are obtained by @dfn{assembling} several other devices, such
16719 as hard disks or partitions, into a new one that behaves as one partition.
16721 Mapped devices are declared using the @code{mapped-device} form,
16722 defined as follows; for examples, see below.
16724 @deftp {Data Type} mapped-device
16725 Objects of this type represent device mappings that will be made when
16726 the system boots up.
16730 This is either a string specifying the name of the block device to be mapped,
16731 such as @code{"/dev/sda3"}, or a list of such strings when several devices
16732 need to be assembled for creating a new one. In case of LVM this is a
16733 string specifying name of the volume group to be mapped.
16736 This string specifies the name of the resulting mapped device. For
16737 kernel mappers such as encrypted devices of type @code{luks-device-mapping},
16738 specifying @code{"my-partition"} leads to the creation of
16739 the @code{"/dev/mapper/my-partition"} device.
16740 For RAID devices of type @code{raid-device-mapping}, the full device name
16741 such as @code{"/dev/md0"} needs to be given.
16742 LVM logical volumes of type @code{lvm-device-mapping} need to
16743 be specified as @code{"VGNAME-LVNAME"}.
16746 This list of strings specifies names of the resulting mapped devices in case
16747 there are several. The format is identical to @var{target}.
16750 This must be a @code{mapped-device-kind} object, which specifies how
16751 @var{source} is mapped to @var{target}.
16755 @defvr {Scheme Variable} luks-device-mapping
16756 This defines LUKS block device encryption using the @command{cryptsetup}
16757 command from the package with the same name. It relies on the
16758 @code{dm-crypt} Linux kernel module.
16761 @defvr {Scheme Variable} raid-device-mapping
16762 This defines a RAID device, which is assembled using the @code{mdadm}
16763 command from the package with the same name. It requires a Linux kernel
16764 module for the appropriate RAID level to be loaded, such as @code{raid456}
16765 for RAID-4, RAID-5 or RAID-6, or @code{raid10} for RAID-10.
16768 @cindex LVM, logical volume manager
16769 @defvr {Scheme Variable} lvm-device-mapping
16770 This defines one or more logical volumes for the Linux
16771 @uref{https://www.sourceware.org/lvm2/, Logical Volume Manager (LVM)}.
16772 The volume group is activated by the @command{vgchange} command from the
16773 @code{lvm2} package.
16776 @cindex disk encryption
16778 The following example specifies a mapping from @file{/dev/sda3} to
16779 @file{/dev/mapper/home} using LUKS---the
16780 @url{https://gitlab.com/cryptsetup/cryptsetup,Linux Unified Key Setup}, a
16781 standard mechanism for disk encryption.
16782 The @file{/dev/mapper/home}
16783 device can then be used as the @code{device} of a @code{file-system}
16784 declaration (@pxref{File Systems}).
16788 (source "/dev/sda3")
16790 (type luks-device-mapping))
16793 Alternatively, to become independent of device numbering, one may obtain
16794 the LUKS UUID (@dfn{unique identifier}) of the source device by a
16798 cryptsetup luksUUID /dev/sda3
16801 and use it as follows:
16805 (source (uuid "cb67fc72-0d54-4c88-9d4b-b225f30b0f44"))
16807 (type luks-device-mapping))
16810 @cindex swap encryption
16811 It is also desirable to encrypt swap space, since swap space may contain
16812 sensitive data. One way to accomplish that is to use a swap file in a
16813 file system on a device mapped via LUKS encryption. In this way, the
16814 swap file is encrypted because the entire device is encrypted.
16815 @xref{Swap Space}, or @xref{Preparing for Installation,,Disk
16816 Partitioning}, for an example.
16818 A RAID device formed of the partitions @file{/dev/sda1} and @file{/dev/sdb1}
16819 may be declared as follows:
16823 (source (list "/dev/sda1" "/dev/sdb1"))
16824 (target "/dev/md0")
16825 (type raid-device-mapping))
16828 The @file{/dev/md0} device can then be used as the @code{device} of a
16829 @code{file-system} declaration (@pxref{File Systems}).
16830 Note that the RAID level need not be given; it is chosen during the
16831 initial creation and formatting of the RAID device and is determined
16832 automatically later.
16834 LVM logical volumes ``alpha'' and ``beta'' from volume group ``vg0'' can
16835 be declared as follows:
16840 (targets (list "vg0-alpha" "vg0-beta"))
16841 (type lvm-device-mapping))
16844 Devices @file{/dev/mapper/vg0-alpha} and @file{/dev/mapper/vg0-beta} can
16845 then be used as the @code{device} of a @code{file-system} declaration
16846 (@pxref{File Systems}).
16849 @section Swap Space
16852 Swap space, as it is commonly called, is a disk area specifically
16853 designated for paging: the process in charge of memory management
16854 (the Linux kernel or Hurd's default pager) can decide that some memory
16855 pages stored in RAM which belong to a running program but are unused
16856 should be stored on disk instead. It unloads those from the RAM,
16857 freeing up precious fast memory, and writes them to the swap space. If
16858 the program tries to access that very page, the memory management
16859 process loads it back into memory for the program to use.
16861 A common misconception about swap is that it is only useful when small
16862 amounts of RAM are available to the system. However, it should be noted
16863 that kernels often use all available RAM for disk access caching to make
16864 I/O faster, and thus paging out unused portions of program memory will
16865 expand the RAM available for such caching.
16867 For a more detailed description of how memory is managed from the
16868 viewpoint of a monolithic kernel, @xref{Memory
16869 Concepts,,, libc, The GNU C Library Reference Manual}.
16871 The Linux kernel has support for swap partitions and swap files: the
16872 former uses a whole disk partition for paging, whereas the second uses a
16873 file on a file system for that (the file system driver needs to support
16874 it). On a comparable setup, both have the same performance, so one
16875 should consider ease of use when deciding between them. Partitions are
16876 ``simpler'' and do not need file system support, but need to be
16877 allocated at disk formatting time (logical volumes notwithstanding),
16878 whereas files can be allocated and deallocated at any time.
16880 Note that swap space is not zeroed on shutdown, so sensitive data (such
16881 as passwords) may linger on it if it was paged out. As such, you should
16882 consider having your swap reside on an encrypted device (@pxref{Mapped
16885 @deftp {Data Type} swap-space
16886 Objects of this type represent swap spaces. They contain the following
16890 @item @code{target}
16891 The device or file to use, either a UUID, a @code{file-system-label} or
16892 a string, as in the definition of a @code{file-system} (@pxref{File
16895 @item @code{dependencies} (default: @code{'()})
16896 A list of @code{file-system} or @code{mapped-device} objects, upon which
16897 the availability of the space depends. Note that just like for
16898 @code{file-system} objects, dependencies which are needed for boot and
16899 mounted in early userspace are not managed by the Shepherd, and so
16900 automatically filtered out for you.
16902 @item @code{priority} (default: @code{#f})
16903 Only supported by the Linux kernel. Either @code{#f} to disable swap
16904 priority, or an integer between 0 and 32767. The kernel will first use
16905 swap spaces of higher priority when paging, and use same priority spaces
16906 on a round-robin basis. The kernel will use swap spaces without a set
16907 priority after prioritized spaces, and in the order that they appeared in
16910 @item @code{discard?} (default: @code{#f})
16911 Only supported by the Linux kernel. When true, the kernel will notify
16912 the disk controller of discarded pages, for example with the TRIM
16913 operation on Solid State Drives.
16918 Here are some examples:
16921 (swap-space (target (uuid "4dab5feb-d176-45de-b287-9b0a6e4c01cb")))
16924 Use the swap partition with the given UUID@. You can learn the UUID of a
16925 Linux swap partition by running @command{swaplabel @var{device}}, where
16926 @var{device} is the @file{/dev} file name of that partition.
16930 (target (file-system-label "swap"))
16931 (dependencies mapped-devices))
16934 Use the partition with label @code{swap}, which can be found after all
16935 the @var{mapped-devices} mapped devices have been opened. Again, the
16936 @command{swaplabel} command allows you to view and change the label of a
16937 Linux swap partition.
16939 Here's a more involved example with the corresponding @code{file-systems} part
16940 of an @code{operating-system} declaration.
16945 (device (file-system-label "root"))
16949 (device (file-system-label "btrfs"))
16950 (mount-point "/btrfs")
16956 (target "/btrfs/swapfile")
16957 (dependencies (filter (file-system-mount-point-predicate "/btrfs")
16961 Use the file @file{/btrfs/swapfile} as swap space, which depends on the
16962 file system mounted at @file{/btrfs}. Note how we use Guile's filter to
16963 select the file system in an elegant fashion!
16965 @node User Accounts
16966 @section User Accounts
16970 @cindex user accounts
16971 User accounts and groups are entirely managed through the
16972 @code{operating-system} declaration. They are specified with the
16973 @code{user-account} and @code{user-group} forms:
16979 (supplementary-groups '("wheel" ;allow use of sudo, etc.
16980 "audio" ;sound card
16981 "video" ;video devices such as webcams
16982 "cdrom")) ;the good ol' CD-ROM
16983 (comment "Bob's sister"))
16986 Here's a user account that uses a different shell and a custom home
16987 directory (the default would be @file{"/home/bob"}):
16993 (comment "Alice's bro")
16994 (shell (file-append zsh "/bin/zsh"))
16995 (home-directory "/home/robert"))
16998 When booting or upon completion of @command{guix system reconfigure},
16999 the system ensures that only the user accounts and groups specified in
17000 the @code{operating-system} declaration exist, and with the specified
17001 properties. Thus, account or group creations or modifications made by
17002 directly invoking commands such as @command{useradd} are lost upon
17003 reconfiguration or reboot. This ensures that the system remains exactly
17006 @deftp {Data Type} user-account
17007 Objects of this type represent user accounts. The following members may
17012 The name of the user account.
17016 This is the name (a string) or identifier (a number) of the user group
17017 this account belongs to.
17019 @item @code{supplementary-groups} (default: @code{'()})
17020 Optionally, this can be defined as a list of group names that this
17021 account belongs to.
17023 @item @code{uid} (default: @code{#f})
17024 This is the user ID for this account (a number), or @code{#f}. In the
17025 latter case, a number is automatically chosen by the system when the
17026 account is created.
17028 @item @code{comment} (default: @code{""})
17029 A comment about the account, such as the account owner's full name.
17031 Note that, for non-system accounts, users are free to change their real
17032 name as it appears in @file{/etc/passwd} using the @command{chfn}
17033 command. When they do, their choice prevails over the system
17034 administrator's choice; reconfiguring does @emph{not} change their name.
17036 @item @code{home-directory}
17037 This is the name of the home directory for the account.
17039 @item @code{create-home-directory?} (default: @code{#t})
17040 Indicates whether the home directory of this account should be created
17041 if it does not exist yet.
17043 @item @code{shell} (default: Bash)
17044 This is a G-expression denoting the file name of a program to be used as
17045 the shell (@pxref{G-Expressions}). For example, you would refer to the
17046 Bash executable like this:
17049 (file-append bash "/bin/bash")
17053 ... and to the Zsh executable like that:
17056 (file-append zsh "/bin/zsh")
17059 @item @code{system?} (default: @code{#f})
17060 This Boolean value indicates whether the account is a ``system''
17061 account. System accounts are sometimes treated specially; for instance,
17062 graphical login managers do not list them.
17064 @anchor{user-account-password}
17065 @cindex password, for user accounts
17066 @item @code{password} (default: @code{#f})
17067 You would normally leave this field to @code{#f}, initialize user
17068 passwords as @code{root} with the @command{passwd} command, and then let
17069 users change it with @command{passwd}. Passwords set with
17070 @command{passwd} are of course preserved across reboot and
17073 If you @emph{do} want to set an initial password for an account, then
17074 this field must contain the encrypted password, as a string. You can use the
17075 @code{crypt} procedure for this purpose:
17082 ;; Specify a SHA-512-hashed initial password.
17083 (password (crypt "InitialPassword!" "$6$abc")))
17087 The hash of this initial password will be available in a file in
17088 @file{/gnu/store}, readable by all the users, so this method must be used with
17092 @xref{Passphrase Storage,,, libc, The GNU C Library Reference Manual}, for
17093 more information on password encryption, and @ref{Encryption,,, guile, GNU
17094 Guile Reference Manual}, for information on Guile's @code{crypt} procedure.
17100 User group declarations are even simpler:
17103 (user-group (name "students"))
17106 @deftp {Data Type} user-group
17107 This type is for, well, user groups. There are just a few fields:
17111 The name of the group.
17113 @item @code{id} (default: @code{#f})
17114 The group identifier (a number). If @code{#f}, a new number is
17115 automatically allocated when the group is created.
17117 @item @code{system?} (default: @code{#f})
17118 This Boolean value indicates whether the group is a ``system'' group.
17119 System groups have low numerical IDs.
17121 @item @code{password} (default: @code{#f})
17122 What, user groups can have a password? Well, apparently yes. Unless
17123 @code{#f}, this field specifies the password of the group.
17128 For convenience, a variable lists all the basic user groups one may
17131 @defvr {Scheme Variable} %base-groups
17132 This is the list of basic user groups that users and/or packages expect
17133 to be present on the system. This includes groups such as ``root'',
17134 ``wheel'', and ``users'', as well as groups used to control access to
17135 specific devices such as ``audio'', ``disk'', and ``cdrom''.
17138 @defvr {Scheme Variable} %base-user-accounts
17139 This is the list of basic system accounts that programs may expect to
17140 find on a GNU/Linux system, such as the ``nobody'' account.
17142 Note that the ``root'' account is not included here. It is a
17143 special-case and is automatically added whether or not it is specified.
17146 @node Keyboard Layout
17147 @section Keyboard Layout
17149 @cindex keyboard layout
17151 To specify what each key of your keyboard does, you need to tell the operating
17152 system what @dfn{keyboard layout} you want to use. The default, when nothing
17153 is specified, is the US English QWERTY layout for 105-key PC keyboards.
17154 However, German speakers will usually prefer the German QWERTZ layout, French
17155 speakers will want the AZERTY layout, and so on; hackers might prefer Dvorak
17156 or bépo, and they might even want to further customize the effect of some of
17157 the keys. This section explains how to get that done.
17159 @cindex keyboard layout, definition
17160 There are three components that will want to know about your keyboard layout:
17164 The @emph{bootloader} may want to know what keyboard layout you want to use
17165 (@pxref{Bootloader Configuration, @code{keyboard-layout}}). This is useful if
17166 you want, for instance, to make sure that you can type the passphrase of your
17167 encrypted root partition using the right layout.
17170 The @emph{operating system kernel}, Linux, will need that so that the console
17171 is properly configured (@pxref{operating-system Reference,
17172 @code{keyboard-layout}}).
17175 The @emph{graphical display server}, usually Xorg, also has its own idea of
17176 the keyboard layout (@pxref{X Window, @code{keyboard-layout}}).
17179 Guix allows you to configure all three separately but, fortunately, it allows
17180 you to share the same keyboard layout for all three components.
17182 @cindex XKB, keyboard layouts
17183 Keyboard layouts are represented by records created by the
17184 @code{keyboard-layout} procedure of @code{(gnu system keyboard)}. Following
17185 the X Keyboard extension (XKB), each layout has four attributes: a name (often
17186 a language code such as ``fi'' for Finnish or ``jp'' for Japanese), an
17187 optional variant name, an optional keyboard model name, and a possibly empty
17188 list of additional options. In most cases the layout name is all you care
17191 @deffn {Scheme Procedure} keyboard-layout @var{name} [@var{variant}] @
17192 [#:model] [#:options '()]
17193 Return a new keyboard layout with the given @var{name} and @var{variant}.
17195 @var{name} must be a string such as @code{"fr"}; @var{variant} must be a
17196 string such as @code{"bepo"} or @code{"nodeadkeys"}. See the
17197 @code{xkeyboard-config} package for valid options.
17200 Here are a few examples:
17203 ;; The German QWERTZ layout. Here we assume a standard
17204 ;; "pc105" keyboard model.
17205 (keyboard-layout "de")
17207 ;; The bépo variant of the French layout.
17208 (keyboard-layout "fr" "bepo")
17210 ;; The Catalan layout.
17211 (keyboard-layout "es" "cat")
17213 ;; Arabic layout with "Alt-Shift" to switch to US layout.
17214 (keyboard-layout "ar,us" #:options '("grp:alt_shift_toggle"))
17216 ;; The Latin American Spanish layout. In addition, the
17217 ;; "Caps Lock" key is used as an additional "Ctrl" key,
17218 ;; and the "Menu" key is used as a "Compose" key to enter
17219 ;; accented letters.
17220 (keyboard-layout "latam"
17221 #:options '("ctrl:nocaps" "compose:menu"))
17223 ;; The Russian layout for a ThinkPad keyboard.
17224 (keyboard-layout "ru" #:model "thinkpad")
17226 ;; The "US international" layout, which is the US layout plus
17227 ;; dead keys to enter accented characters. This is for an
17228 ;; Apple MacBook keyboard.
17229 (keyboard-layout "us" "intl" #:model "macbook78")
17232 See the @file{share/X11/xkb} directory of the @code{xkeyboard-config} package
17233 for a complete list of supported layouts, variants, and models.
17235 @cindex keyboard layout, configuration
17236 Let's say you want your system to use the Turkish keyboard layout throughout
17237 your system---bootloader, console, and Xorg. Here's what your system
17238 configuration would look like:
17240 @findex set-xorg-configuration
17242 ;; Using the Turkish layout for the bootloader, the console,
17247 (keyboard-layout (keyboard-layout "tr")) ;for the console
17248 (bootloader (bootloader-configuration
17249 (bootloader grub-efi-bootloader)
17250 (targets '("/boot/efi"))
17251 (keyboard-layout keyboard-layout))) ;for GRUB
17252 (services (cons (set-xorg-configuration
17253 (xorg-configuration ;for Xorg
17254 (keyboard-layout keyboard-layout)))
17255 %desktop-services)))
17258 In the example above, for GRUB and for Xorg, we just refer to the
17259 @code{keyboard-layout} field defined above, but we could just as well refer to
17260 a different layout. The @code{set-xorg-configuration} procedure communicates
17261 the desired Xorg configuration to the graphical log-in manager, by default
17264 We've discussed how to specify the @emph{default} keyboard layout of your
17265 system when it starts, but you can also adjust it at run time:
17269 If you're using GNOME, its settings panel has a ``Region & Language'' entry
17270 where you can select one or more keyboard layouts.
17273 Under Xorg, the @command{setxkbmap} command (from the same-named package)
17274 allows you to change the current layout. For example, this is how you would
17275 change the layout to US Dvorak:
17278 setxkbmap us dvorak
17282 The @code{loadkeys} command changes the keyboard layout in effect in the Linux
17283 console. However, note that @code{loadkeys} does @emph{not} use the XKB
17284 keyboard layout categorization described above. The command below loads the
17285 French bépo layout:
17296 A @dfn{locale} defines cultural conventions for a particular language
17297 and region of the world (@pxref{Locales,,, libc, The GNU C Library
17298 Reference Manual}). Each locale has a name that typically has the form
17299 @code{@var{language}_@var{territory}.@var{codeset}}---e.g.,
17300 @code{fr_LU.utf8} designates the locale for the French language, with
17301 cultural conventions from Luxembourg, and using the UTF-8 encoding.
17303 @cindex locale definition
17304 Usually, you will want to specify the default locale for the machine
17305 using the @code{locale} field of the @code{operating-system} declaration
17306 (@pxref{operating-system Reference, @code{locale}}).
17308 The selected locale is automatically added to the @dfn{locale
17309 definitions} known to the system if needed, with its codeset inferred
17310 from its name---e.g., @code{bo_CN.utf8} will be assumed to use the
17311 @code{UTF-8} codeset. Additional locale definitions can be specified in
17312 the @code{locale-definitions} slot of @code{operating-system}---this is
17313 useful, for instance, if the codeset could not be inferred from the
17314 locale name. The default set of locale definitions includes some widely
17315 used locales, but not all the available locales, in order to save space.
17317 For instance, to add the North Frisian locale for Germany, the value of
17321 (cons (locale-definition
17322 (name "fy_DE.utf8") (source "fy_DE"))
17323 %default-locale-definitions)
17326 Likewise, to save space, one might want @code{locale-definitions} to
17327 list only the locales that are actually used, as in:
17330 (list (locale-definition
17331 (name "ja_JP.eucjp") (source "ja_JP")
17332 (charset "EUC-JP")))
17336 The compiled locale definitions are available at
17337 @file{/run/current-system/locale/X.Y}, where @code{X.Y} is the libc
17338 version, which is the default location where the GNU@tie{}libc provided
17339 by Guix looks for locale data. This can be overridden using the
17340 @env{LOCPATH} environment variable (@pxref{locales-and-locpath,
17341 @env{LOCPATH} and locale packages}).
17343 The @code{locale-definition} form is provided by the @code{(gnu system
17344 locale)} module. Details are given below.
17346 @deftp {Data Type} locale-definition
17347 This is the data type of a locale definition.
17352 The name of the locale. @xref{Locale Names,,, libc, The GNU C Library
17353 Reference Manual}, for more information on locale names.
17355 @item @code{source}
17356 The name of the source for that locale. This is typically the
17357 @code{@var{language}_@var{territory}} part of the locale name.
17359 @item @code{charset} (default: @code{"UTF-8"})
17360 The ``character set'' or ``code set'' for that locale,
17361 @uref{https://www.iana.org/assignments/character-sets, as defined by
17367 @defvr {Scheme Variable} %default-locale-definitions
17368 A list of commonly used UTF-8 locales, used as the default
17369 value of the @code{locale-definitions} field of @code{operating-system}
17372 @cindex locale name
17373 @cindex normalized codeset in locale names
17374 These locale definitions use the @dfn{normalized codeset} for the part
17375 that follows the dot in the name (@pxref{Using gettextized software,
17376 normalized codeset,, libc, The GNU C Library Reference Manual}). So for
17377 instance it has @code{uk_UA.utf8} but @emph{not}, say,
17378 @code{uk_UA.UTF-8}.
17381 @subsection Locale Data Compatibility Considerations
17383 @cindex incompatibility, of locale data
17384 @code{operating-system} declarations provide a @code{locale-libcs} field
17385 to specify the GNU@tie{}libc packages that are used to compile locale
17386 declarations (@pxref{operating-system Reference}). ``Why would I
17387 care?'', you may ask. Well, it turns out that the binary format of
17388 locale data is occasionally incompatible from one libc version to
17391 @c See <https://sourceware.org/ml/libc-alpha/2015-09/msg00575.html>
17392 @c and <https://lists.gnu.org/archive/html/guix-devel/2015-08/msg00737.html>.
17393 For instance, a program linked against libc version 2.21 is unable to
17394 read locale data produced with libc 2.22; worse, that program
17395 @emph{aborts} instead of simply ignoring the incompatible locale
17396 data@footnote{Versions 2.23 and later of GNU@tie{}libc will simply skip
17397 the incompatible locale data, which is already an improvement.}.
17398 Similarly, a program linked against libc 2.22 can read most, but not
17399 all, of the locale data from libc 2.21 (specifically, @env{LC_COLLATE}
17400 data is incompatible); thus calls to @code{setlocale} may fail, but
17401 programs will not abort.
17403 The ``problem'' with Guix is that users have a lot of freedom: They can
17404 choose whether and when to upgrade software in their profiles, and might
17405 be using a libc version different from the one the system administrator
17406 used to build the system-wide locale data.
17408 Fortunately, unprivileged users can also install their own locale data
17409 and define @env{GUIX_LOCPATH} accordingly (@pxref{locales-and-locpath,
17410 @env{GUIX_LOCPATH} and locale packages}).
17412 Still, it is best if the system-wide locale data at
17413 @file{/run/current-system/locale} is built for all the libc versions
17414 actually in use on the system, so that all the programs can access
17415 it---this is especially crucial on a multi-user system. To do that, the
17416 administrator can specify several libc packages in the
17417 @code{locale-libcs} field of @code{operating-system}:
17420 (use-package-modules base)
17424 (locale-libcs (list glibc-2.21 (canonical-package glibc))))
17427 This example would lead to a system containing locale definitions for
17428 both libc 2.21 and the current version of libc in
17429 @file{/run/current-system/locale}.
17435 @cindex system services
17436 An important part of preparing an @code{operating-system} declaration is
17437 listing @dfn{system services} and their configuration (@pxref{Using the
17438 Configuration System}). System services are typically daemons launched
17439 when the system boots, or other actions needed at that time---e.g.,
17440 configuring network access.
17442 Guix has a broad definition of ``service'' (@pxref{Service
17443 Composition}), but many services are managed by the GNU@tie{}Shepherd
17444 (@pxref{Shepherd Services}). On a running system, the @command{herd}
17445 command allows you to list the available services, show their status,
17446 start and stop them, or do other specific operations (@pxref{Jump
17447 Start,,, shepherd, The GNU Shepherd Manual}). For example:
17453 The above command, run as @code{root}, lists the currently defined
17454 services. The @command{herd doc} command shows a synopsis of the given
17455 service and its associated actions:
17459 Run libc's name service cache daemon (nscd).
17461 # herd doc nscd action invalidate
17462 invalidate: Invalidate the given cache--e.g., 'hosts' for host name lookups.
17465 The @command{start}, @command{stop}, and @command{restart} sub-commands
17466 have the effect you would expect. For instance, the commands below stop
17467 the nscd service and restart the Xorg display server:
17471 Service nscd has been stopped.
17472 # herd restart xorg-server
17473 Service xorg-server has been stopped.
17474 Service xorg-server has been started.
17477 The following sections document the available services, starting with
17478 the core services, that may be used in an @code{operating-system}
17482 * Base Services:: Essential system services.
17483 * Scheduled Job Execution:: The mcron service.
17484 * Log Rotation:: The rottlog service.
17485 * Networking Setup:: Setting up network interfaces.
17486 * Networking Services:: Firewall, SSH daemon, etc.
17487 * Unattended Upgrades:: Automated system upgrades.
17488 * X Window:: Graphical display.
17489 * Printing Services:: Local and remote printer support.
17490 * Desktop Services:: D-Bus and desktop services.
17491 * Sound Services:: ALSA and Pulseaudio services.
17492 * Database Services:: SQL databases, key-value stores, etc.
17493 * Mail Services:: IMAP, POP3, SMTP, and all that.
17494 * Messaging Services:: Messaging services.
17495 * Telephony Services:: Telephony services.
17496 * File-Sharing Services:: File-sharing services.
17497 * Monitoring Services:: Monitoring services.
17498 * Kerberos Services:: Kerberos services.
17499 * LDAP Services:: LDAP services.
17500 * Web Services:: Web servers.
17501 * Certificate Services:: TLS certificates via Let's Encrypt.
17502 * DNS Services:: DNS daemons.
17503 * VPN Services:: VPN daemons.
17504 * Network File System:: NFS related services.
17505 * Continuous Integration:: Cuirass and Laminar services.
17506 * Power Management Services:: Extending battery life.
17507 * Audio Services:: The MPD.
17508 * Virtualization Services:: Virtualization services.
17509 * Version Control Services:: Providing remote access to Git repositories.
17510 * Game Services:: Game servers.
17511 * PAM Mount Service:: Service to mount volumes when logging in.
17512 * Guix Services:: Services relating specifically to Guix.
17513 * Linux Services:: Services tied to the Linux kernel.
17514 * Hurd Services:: Services specific for a Hurd System.
17515 * Miscellaneous Services:: Other services.
17518 @node Base Services
17519 @subsection Base Services
17521 The @code{(gnu services base)} module provides definitions for the basic
17522 services that one expects from the system. The services exported by
17523 this module are listed below.
17525 @defvr {Scheme Variable} %base-services
17526 This variable contains a list of basic services (@pxref{Service Types
17527 and Services}, for more information on service objects) one would
17528 expect from the system: a login service (mingetty) on each tty, syslogd,
17529 the libc name service cache daemon (nscd), the udev device manager, and
17532 This is the default value of the @code{services} field of
17533 @code{operating-system} declarations. Usually, when customizing a
17534 system, you will want to append services to @code{%base-services}, like
17538 (append (list (service avahi-service-type)
17539 (service openssh-service-type))
17544 @defvr {Scheme Variable} special-files-service-type
17545 This is the service that sets up ``special files'' such as
17546 @file{/bin/sh}; an instance of it is part of @code{%base-services}.
17548 The value associated with @code{special-files-service-type} services
17549 must be a list of tuples where the first element is the ``special file''
17550 and the second element is its target. By default it is:
17552 @cindex @file{/bin/sh}
17553 @cindex @file{sh}, in @file{/bin}
17555 `(("/bin/sh" ,(file-append bash "/bin/sh")))
17558 @cindex @file{/usr/bin/env}
17559 @cindex @file{env}, in @file{/usr/bin}
17560 If you want to add, say, @code{/usr/bin/env} to your system, you can
17564 `(("/bin/sh" ,(file-append bash "/bin/sh"))
17565 ("/usr/bin/env" ,(file-append coreutils "/bin/env")))
17568 Since this is part of @code{%base-services}, you can use
17569 @code{modify-services} to customize the set of special files
17570 (@pxref{Service Reference, @code{modify-services}}). But the simple way
17571 to add a special file is @i{via} the @code{extra-special-file} procedure
17575 @deffn {Scheme Procedure} extra-special-file @var{file} @var{target}
17576 Use @var{target} as the ``special file'' @var{file}.
17578 For example, adding the following lines to the @code{services} field of
17579 your operating system declaration leads to a @file{/usr/bin/env}
17583 (extra-special-file "/usr/bin/env"
17584 (file-append coreutils "/bin/env"))
17588 @deffn {Scheme Procedure} host-name-service @var{name}
17589 Return a service that sets the host name to @var{name}.
17592 @defvr {Scheme Variable} console-font-service-type
17593 Install the given fonts on the specified ttys (fonts are per
17594 virtual console on the kernel Linux). The value of this service is a list of
17595 tty/font pairs. The font can be the name of a font provided by the @code{kbd}
17596 package or any valid argument to @command{setfont}, as in this example:
17599 `(("tty1" . "LatGrkCyr-8x16")
17600 ("tty2" . ,(file-append
17602 "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
17603 ("tty3" . ,(file-append
17605 "/share/consolefonts/ter-132n"))) ; for HDPI
17609 @deffn {Scheme Procedure} login-service @var{config}
17610 Return a service to run login according to @var{config}, a
17611 @code{<login-configuration>} object, which specifies the message of the day,
17612 among other things.
17615 @deftp {Data Type} login-configuration
17616 This is the data type representing the configuration of login.
17621 @cindex message of the day
17622 A file-like object containing the ``message of the day''.
17624 @item @code{allow-empty-passwords?} (default: @code{#t})
17625 Allow empty passwords by default so that first-time users can log in when
17626 the 'root' account has just been created.
17631 @deffn {Scheme Procedure} mingetty-service @var{config}
17632 Return a service to run mingetty according to @var{config}, a
17633 @code{<mingetty-configuration>} object, which specifies the tty to run, among
17637 @deftp {Data Type} mingetty-configuration
17638 This is the data type representing the configuration of Mingetty, which
17639 provides the default implementation of virtual console log-in.
17644 The name of the console this Mingetty runs on---e.g., @code{"tty1"}.
17646 @item @code{auto-login} (default: @code{#f})
17647 When true, this field must be a string denoting the user name under
17648 which the system automatically logs in. When it is @code{#f}, a
17649 user name and password must be entered to log in.
17651 @item @code{login-program} (default: @code{#f})
17652 This must be either @code{#f}, in which case the default log-in program
17653 is used (@command{login} from the Shadow tool suite), or a gexp denoting
17654 the name of the log-in program.
17656 @item @code{login-pause?} (default: @code{#f})
17657 When set to @code{#t} in conjunction with @var{auto-login}, the user
17658 will have to press a key before the log-in shell is launched.
17660 @item @code{clear-on-logout?} (default: @code{#t})
17661 When set to @code{#t}, the screen will be cleared after logout.
17663 @item @code{mingetty} (default: @var{mingetty})
17664 The Mingetty package to use.
17669 @deffn {Scheme Procedure} agetty-service @var{config}
17670 Return a service to run agetty according to @var{config}, an
17671 @code{<agetty-configuration>} object, which specifies the tty to run,
17672 among other things.
17675 @deftp {Data Type} agetty-configuration
17676 This is the data type representing the configuration of agetty, which
17677 implements virtual and serial console log-in. See the @code{agetty(8)}
17678 man page for more information.
17683 The name of the console this agetty runs on, as a string---e.g.,
17684 @code{"ttyS0"}. This argument is optional, it will default to
17685 a reasonable default serial port used by the kernel Linux.
17687 For this, if there is a value for an option @code{agetty.tty} in the kernel
17688 command line, agetty will extract the device name of the serial port
17689 from it and use that.
17691 If not and if there is a value for an option @code{console} with a tty in
17692 the Linux command line, agetty will extract the device name of the
17693 serial port from it and use that.
17695 In both cases, agetty will leave the other serial device settings
17696 (baud rate etc.)@: alone---in the hope that Linux pinned them to the
17699 @item @code{baud-rate} (default: @code{#f})
17700 A string containing a comma-separated list of one or more baud rates, in
17703 @item @code{term} (default: @code{#f})
17704 A string containing the value used for the @env{TERM} environment
17707 @item @code{eight-bits?} (default: @code{#f})
17708 When @code{#t}, the tty is assumed to be 8-bit clean, and parity detection is
17711 @item @code{auto-login} (default: @code{#f})
17712 When passed a login name, as a string, the specified user will be logged
17713 in automatically without prompting for their login name or password.
17715 @item @code{no-reset?} (default: @code{#f})
17716 When @code{#t}, don't reset terminal cflags (control modes).
17718 @item @code{host} (default: @code{#f})
17719 This accepts a string containing the ``login_host'', which will be written
17720 into the @file{/var/run/utmpx} file.
17722 @item @code{remote?} (default: @code{#f})
17723 When set to @code{#t} in conjunction with @var{host}, this will add an
17724 @code{-r} fakehost option to the command line of the login program
17725 specified in @var{login-program}.
17727 @item @code{flow-control?} (default: @code{#f})
17728 When set to @code{#t}, enable hardware (RTS/CTS) flow control.
17730 @item @code{no-issue?} (default: @code{#f})
17731 When set to @code{#t}, the contents of the @file{/etc/issue} file will
17732 not be displayed before presenting the login prompt.
17734 @item @code{init-string} (default: @code{#f})
17735 This accepts a string that will be sent to the tty or modem before
17736 sending anything else. It can be used to initialize a modem.
17738 @item @code{no-clear?} (default: @code{#f})
17739 When set to @code{#t}, agetty will not clear the screen before showing
17742 @item @code{login-program} (default: (file-append shadow "/bin/login"))
17743 This must be either a gexp denoting the name of a log-in program, or
17744 unset, in which case the default value is the @command{login} from the
17747 @item @code{local-line} (default: @code{#f})
17748 Control the CLOCAL line flag. This accepts one of three symbols as
17749 arguments, @code{'auto}, @code{'always}, or @code{'never}. If @code{#f},
17750 the default value chosen by agetty is @code{'auto}.
17752 @item @code{extract-baud?} (default: @code{#f})
17753 When set to @code{#t}, instruct agetty to try to extract the baud rate
17754 from the status messages produced by certain types of modems.
17756 @item @code{skip-login?} (default: @code{#f})
17757 When set to @code{#t}, do not prompt the user for a login name. This
17758 can be used with @var{login-program} field to use non-standard login
17761 @item @code{no-newline?} (default: @code{#f})
17762 When set to @code{#t}, do not print a newline before printing the
17763 @file{/etc/issue} file.
17765 @c Is this dangerous only when used with login-program, or always?
17766 @item @code{login-options} (default: @code{#f})
17767 This option accepts a string containing options that are passed to the
17768 login program. When used with the @var{login-program}, be aware that a
17769 malicious user could try to enter a login name containing embedded
17770 options that could be parsed by the login program.
17772 @item @code{login-pause} (default: @code{#f})
17773 When set to @code{#t}, wait for any key before showing the login prompt.
17774 This can be used in conjunction with @var{auto-login} to save memory by
17775 lazily spawning shells.
17777 @item @code{chroot} (default: @code{#f})
17778 Change root to the specified directory. This option accepts a directory
17781 @item @code{hangup?} (default: @code{#f})
17782 Use the Linux system call @code{vhangup} to do a virtual hangup of the
17783 specified terminal.
17785 @item @code{keep-baud?} (default: @code{#f})
17786 When set to @code{#t}, try to keep the existing baud rate. The baud
17787 rates from @var{baud-rate} are used when agetty receives a @key{BREAK}
17790 @item @code{timeout} (default: @code{#f})
17791 When set to an integer value, terminate if no user name could be read
17792 within @var{timeout} seconds.
17794 @item @code{detect-case?} (default: @code{#f})
17795 When set to @code{#t}, turn on support for detecting an uppercase-only
17796 terminal. This setting will detect a login name containing only
17797 uppercase letters as indicating an uppercase-only terminal and turn on
17798 some upper-to-lower case conversions. Note that this will not support
17799 Unicode characters.
17801 @item @code{wait-cr?} (default: @code{#f})
17802 When set to @code{#t}, wait for the user or modem to send a
17803 carriage-return or linefeed character before displaying
17804 @file{/etc/issue} or login prompt. This is typically used with the
17805 @var{init-string} option.
17807 @item @code{no-hints?} (default: @code{#f})
17808 When set to @code{#t}, do not print hints about Num, Caps, and Scroll
17811 @item @code{no-hostname?} (default: @code{#f})
17812 By default, the hostname is printed. When this option is set to
17813 @code{#t}, no hostname will be shown at all.
17815 @item @code{long-hostname?} (default: @code{#f})
17816 By default, the hostname is only printed until the first dot. When this
17817 option is set to @code{#t}, the fully qualified hostname by
17818 @code{gethostname} or @code{getaddrinfo} is shown.
17820 @item @code{erase-characters} (default: @code{#f})
17821 This option accepts a string of additional characters that should be
17822 interpreted as backspace when the user types their login name.
17824 @item @code{kill-characters} (default: @code{#f})
17825 This option accepts a string that should be interpreted to mean ``ignore
17826 all previous characters'' (also called a ``kill'' character) when the user
17827 types their login name.
17829 @item @code{chdir} (default: @code{#f})
17830 This option accepts, as a string, a directory path that will be changed
17833 @item @code{delay} (default: @code{#f})
17834 This options accepts, as an integer, the number of seconds to sleep
17835 before opening the tty and displaying the login prompt.
17837 @item @code{nice} (default: @code{#f})
17838 This option accepts, as an integer, the nice value with which to run the
17839 @command{login} program.
17841 @item @code{extra-options} (default: @code{'()})
17842 This option provides an ``escape hatch'' for the user to provide arbitrary
17843 command-line arguments to @command{agetty} as a list of strings.
17845 @item @code{shepherd-requirement} (default: @code{'()})
17846 The option can be used to provides extra shepherd requirements (for example
17847 @code{'syslogd}) to the respective @code{'term-}* shepherd service.
17852 @deffn {Scheme Procedure} kmscon-service-type @var{config}
17853 Return a service to run @uref{https://www.freedesktop.org/wiki/Software/kmscon,kmscon}
17854 according to @var{config}, a @code{<kmscon-configuration>} object, which
17855 specifies the tty to run, among other things.
17858 @deftp {Data Type} kmscon-configuration
17859 This is the data type representing the configuration of Kmscon, which
17860 implements virtual console log-in.
17864 @item @code{virtual-terminal}
17865 The name of the console this Kmscon runs on---e.g., @code{"tty1"}.
17867 @item @code{login-program} (default: @code{#~(string-append #$shadow "/bin/login")})
17868 A gexp denoting the name of the log-in program. The default log-in program is
17869 @command{login} from the Shadow tool suite.
17871 @item @code{login-arguments} (default: @code{'("-p")})
17872 A list of arguments to pass to @command{login}.
17874 @item @code{auto-login} (default: @code{#f})
17875 When passed a login name, as a string, the specified user will be logged
17876 in automatically without prompting for their login name or password.
17878 @item @code{hardware-acceleration?} (default: #f)
17879 Whether to use hardware acceleration.
17881 @item @code{font-engine} (default: @code{"pango"})
17882 Font engine used in Kmscon.
17884 @item @code{font-size} (default: @code{12})
17885 Font size used in Kmscon.
17887 @item @code{keyboard-layout} (default: @code{#f})
17888 If this is @code{#f}, Kmscon uses the default keyboard layout---usually US
17889 English (``qwerty'') for a 105-key PC keyboard.
17891 Otherwise this must be a @code{keyboard-layout} object specifying the
17892 keyboard layout. @xref{Keyboard Layout}, for more information on how to
17893 specify the keyboard layout.
17895 @item @code{kmscon} (default: @var{kmscon})
17896 The Kmscon package to use.
17901 @cindex name service cache daemon
17903 @deffn {Scheme Procedure} nscd-service [@var{config}] [#:glibc glibc] @
17904 [#:name-services '()]
17905 Return a service that runs the libc name service cache daemon (nscd) with the
17906 given @var{config}---an @code{<nscd-configuration>} object. @xref{Name
17907 Service Switch}, for an example.
17909 For convenience, the Shepherd service for nscd provides the following actions:
17913 @cindex cache invalidation, nscd
17914 @cindex nscd, cache invalidation
17915 This invalidate the given cache. For instance, running:
17918 herd invalidate nscd hosts
17922 invalidates the host name lookup cache of nscd.
17925 Running @command{herd statistics nscd} displays information about nscd usage
17931 @defvr {Scheme Variable} %nscd-default-configuration
17932 This is the default @code{<nscd-configuration>} value (see below) used
17933 by @code{nscd-service}. It uses the caches defined by
17934 @code{%nscd-default-caches}; see below.
17937 @deftp {Data Type} nscd-configuration
17938 This is the data type representing the name service cache daemon (nscd)
17943 @item @code{name-services} (default: @code{'()})
17944 List of packages denoting @dfn{name services} that must be visible to
17945 the nscd---e.g., @code{(list @var{nss-mdns})}.
17947 @item @code{glibc} (default: @var{glibc})
17948 Package object denoting the GNU C Library providing the @command{nscd}
17951 @item @code{log-file} (default: @code{"/var/log/nscd.log"})
17952 Name of the nscd log file. This is where debugging output goes when
17953 @code{debug-level} is strictly positive.
17955 @item @code{debug-level} (default: @code{0})
17956 Integer denoting the debugging levels. Higher numbers mean that more
17957 debugging output is logged.
17959 @item @code{caches} (default: @code{%nscd-default-caches})
17960 List of @code{<nscd-cache>} objects denoting things to be cached; see
17966 @deftp {Data Type} nscd-cache
17967 Data type representing a cache database of nscd and its parameters.
17971 @item @code{database}
17972 This is a symbol representing the name of the database to be cached.
17973 Valid values are @code{passwd}, @code{group}, @code{hosts}, and
17974 @code{services}, which designate the corresponding NSS database
17975 (@pxref{NSS Basics,,, libc, The GNU C Library Reference Manual}).
17977 @item @code{positive-time-to-live}
17978 @itemx @code{negative-time-to-live} (default: @code{20})
17979 A number representing the number of seconds during which a positive or
17980 negative lookup result remains in cache.
17982 @item @code{check-files?} (default: @code{#t})
17983 Whether to check for updates of the files corresponding to
17986 For instance, when @var{database} is @code{hosts}, setting this flag
17987 instructs nscd to check for updates in @file{/etc/hosts} and to take
17990 @item @code{persistent?} (default: @code{#t})
17991 Whether the cache should be stored persistently on disk.
17993 @item @code{shared?} (default: @code{#t})
17994 Whether the cache should be shared among users.
17996 @item @code{max-database-size} (default: 32@tie{}MiB)
17997 Maximum size in bytes of the database cache.
17999 @c XXX: 'suggested-size' and 'auto-propagate?' seem to be expert
18000 @c settings, so leave them out.
18005 @defvr {Scheme Variable} %nscd-default-caches
18006 List of @code{<nscd-cache>} objects used by default by
18007 @code{nscd-configuration} (see above).
18009 It enables persistent and aggressive caching of service and host name
18010 lookups. The latter provides better host name lookup performance,
18011 resilience in the face of unreliable name servers, and also better
18012 privacy---often the result of host name lookups is in local cache, so
18013 external name servers do not even need to be queried.
18016 @anchor{syslog-configuration-type}
18019 @deftp {Data Type} syslog-configuration
18020 This data type represents the configuration of the syslog daemon.
18023 @item @code{syslogd} (default: @code{#~(string-append #$inetutils "/libexec/syslogd")})
18024 The syslog daemon to use.
18026 @item @code{config-file} (default: @code{%default-syslog.conf})
18027 The syslog configuration file to use.
18032 @anchor{syslog-service}
18034 @deffn {Scheme Procedure} syslog-service @var{config}
18035 Return a service that runs a syslog daemon according to @var{config}.
18037 @xref{syslogd invocation,,, inetutils, GNU Inetutils}, for more
18038 information on the configuration file syntax.
18041 @defvr {Scheme Variable} guix-service-type
18042 This is the type of the service that runs the build daemon,
18043 @command{guix-daemon} (@pxref{Invoking guix-daemon}). Its value must be a
18044 @code{guix-configuration} record as described below.
18047 @anchor{guix-configuration-type}
18048 @deftp {Data Type} guix-configuration
18049 This data type represents the configuration of the Guix build daemon.
18050 @xref{Invoking guix-daemon}, for more information.
18053 @item @code{guix} (default: @var{guix})
18054 The Guix package to use.
18056 @item @code{build-group} (default: @code{"guixbuild"})
18057 Name of the group for build user accounts.
18059 @item @code{build-accounts} (default: @code{10})
18060 Number of build user accounts to create.
18062 @item @code{authorize-key?} (default: @code{#t})
18063 @cindex substitutes, authorization thereof
18064 Whether to authorize the substitute keys listed in
18065 @code{authorized-keys}---by default that of
18066 @code{@value{SUBSTITUTE-SERVER-1}} and
18067 @code{@value{SUBSTITUTE-SERVER-2}}
18068 (@pxref{Substitutes}).
18070 When @code{authorize-key?} is true, @file{/etc/guix/acl} cannot be
18071 changed by invoking @command{guix archive --authorize}. You must
18072 instead adjust @code{guix-configuration} as you wish and reconfigure the
18073 system. This ensures that your operating system configuration file is
18077 When booting or reconfiguring to a system where @code{authorize-key?}
18078 is true, the existing @file{/etc/guix/acl} file is backed up as
18079 @file{/etc/guix/acl.bak} if it was determined to be a manually modified
18080 file. This is to facilitate migration from earlier versions, which
18081 allowed for in-place modifications to @file{/etc/guix/acl}.
18084 @vindex %default-authorized-guix-keys
18085 @item @code{authorized-keys} (default: @code{%default-authorized-guix-keys})
18086 The list of authorized key files for archive imports, as a list of
18087 string-valued gexps (@pxref{Invoking guix archive}). By default, it
18088 contains that of @code{@value{SUBSTITUTE-SERVER-1}} and
18089 @code{@value{SUBSTITUTE-SERVER-2}} (@pxref{Substitutes}). See
18090 @code{substitute-urls} below for an example on how to change it.
18092 @item @code{use-substitutes?} (default: @code{#t})
18093 Whether to use substitutes.
18095 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
18096 The list of URLs where to look for substitutes by default.
18098 Suppose you would like to fetch substitutes from @code{guix.example.org}
18099 in addition to @code{@value{SUBSTITUTE-SERVER-1}}. You will need to do
18100 two things: (1) add @code{guix.example.org} to @code{substitute-urls},
18101 and (2) authorize its signing key, having done appropriate checks
18102 (@pxref{Substitute Server Authorization}). The configuration below does
18106 (guix-configuration
18108 (append (list "https://guix.example.org")
18109 %default-substitute-urls))
18111 (append (list (local-file "./guix.example.org-key.pub"))
18112 %default-authorized-guix-keys)))
18115 This example assumes that the file @file{./guix.example.org-key.pub}
18116 contains the public key that @code{guix.example.org} uses to sign
18119 @item @code{generate-substitute-key?} (default: @code{#t})
18120 Whether to generate a @dfn{substitute key pair} under
18121 @file{/etc/guix/signing-key.pub} and @file{/etc/guix/signing-key.sec} if
18122 there is not already one.
18124 This key pair is used when exporting store items, for instance with
18125 @command{guix publish} (@pxref{Invoking guix publish}) or @command{guix
18126 archive} (@pxref{Invoking guix archive}). Generating a key pair takes a
18127 few seconds when enough entropy is available and is only done once; you
18128 might want to turn it off for instance in a virtual machine that does
18129 not need it and where the extra boot time is a problem.
18131 @item @code{max-silent-time} (default: @code{0})
18132 @itemx @code{timeout} (default: @code{0})
18133 The number of seconds of silence and the number of seconds of activity,
18134 respectively, after which a build process times out. A value of zero
18135 disables the timeout.
18137 @item @code{log-compression} (default: @code{'gzip})
18138 The type of compression used for build logs---one of @code{gzip},
18139 @code{bzip2}, or @code{none}.
18141 @item @code{discover?} (default: @code{#f})
18142 Whether to discover substitute servers on the local network using mDNS
18145 @item @code{extra-options} (default: @code{'()})
18146 List of extra command-line options for @command{guix-daemon}.
18148 @item @code{log-file} (default: @code{"/var/log/guix-daemon.log"})
18149 File where @command{guix-daemon}'s standard output and standard error
18152 @cindex HTTP proxy, for @code{guix-daemon}
18153 @cindex proxy, for @code{guix-daemon} HTTP access
18154 @item @code{http-proxy} (default: @code{#f})
18155 The URL of the HTTP and HTTPS proxy used for downloading fixed-output
18156 derivations and substitutes.
18158 It is also possible to change the daemon's proxy at run time through the
18159 @code{set-http-proxy} action, which restarts it:
18162 herd set-http-proxy guix-daemon http://localhost:8118
18165 To clear the proxy settings, run:
18168 herd set-http-proxy guix-daemon
18171 @item @code{tmpdir} (default: @code{#f})
18172 A directory path where the @command{guix-daemon} will perform builds.
18177 @deftp {Data Type} guix-extension
18179 This data type represents the parameters of the Guix build daemon that
18180 are extendable. This is the type of the object that must be used within
18181 a guix service extension.
18182 @xref{Service Composition}, for more information.
18185 @item @code{authorized-keys} (default: @code{'()})
18186 A list of file-like objects where each element contains a public key.
18188 @item @code{substitute-urls} (default: @code{'()})
18189 A list of strings where each element is a substitute URL.
18191 @item @code{chroot-directories} (default: @code{'()})
18192 A list of file-like objects or strings pointing to additional directories the build daemon can use.
18196 @deffn {Scheme Procedure} udev-service [#:udev @var{eudev} #:rules @code{'()}]
18197 Run @var{udev}, which populates the @file{/dev} directory dynamically.
18198 udev rules can be provided as a list of files through the @var{rules}
18199 variable. The procedures @code{udev-rule}, @code{udev-rules-service}
18200 and @code{file->udev-rule} from @code{(gnu services base)} simplify the
18201 creation of such rule files.
18203 The @command{herd rules udev} command, as root, returns the name of the
18204 directory containing all the active udev rules.
18207 @deffn {Scheme Procedure} udev-rule [@var{file-name} @var{contents}]
18208 Return a udev-rule file named @var{file-name} containing the rules
18209 defined by the @var{contents} literal.
18211 In the following example, a rule for a USB device is defined to be
18212 stored in the file @file{90-usb-thing.rules}. The rule runs a script
18213 upon detecting a USB device with a given product identifier.
18216 (define %example-udev-rule
18218 "90-usb-thing.rules"
18219 (string-append "ACTION==\"add\", SUBSYSTEM==\"usb\", "
18220 "ATTR@{product@}==\"Example\", "
18221 "RUN+=\"/path/to/script\"")))
18225 @deffn {Scheme Procedure} udev-rules-service [@var{name} @var{rules}] @
18226 [#:groups @var{groups}]
18227 Return a service that extends @code{udev-service-type } with @var{rules}
18228 and @code{account-service-type} with @var{groups} as system groups.
18229 This works by creating a singleton service type
18230 @code{@var{name}-udev-rules}, of which the returned service is an
18233 Here we show how it can be used to extend @code{udev-service-type} with the
18234 previously defined rule @code{%example-udev-rule}.
18240 (cons (udev-rules-service 'usb-thing %example-udev-rule)
18241 %desktop-services)))
18245 @deffn {Scheme Procedure} file->udev-rule [@var{file-name} @var{file}]
18246 Return a udev file named @var{file-name} containing the rules defined
18247 within @var{file}, a file-like object.
18249 The following example showcases how we can use an existing rule file.
18252 (use-modules (guix download) ;for url-fetch
18253 (guix packages) ;for origin
18256 (define %android-udev-rules
18258 "51-android-udev.rules"
18259 (let ((version "20170910"))
18262 (uri (string-append "https://raw.githubusercontent.com/M0Rf30/"
18263 "android-udev-rules/" version "/51-android.rules"))
18265 (base32 "0lmmagpyb6xsq6zcr2w1cyx9qmjqmajkvrdbhjx32gqf1d9is003"))))))
18269 Additionally, Guix package definitions can be included in @var{rules} in
18270 order to extend the udev rules with the definitions found under their
18271 @file{lib/udev/rules.d} sub-directory. In lieu of the previous
18272 @var{file->udev-rule} example, we could have used the
18273 @var{android-udev-rules} package which exists in Guix in the @code{(gnu
18274 packages android)} module.
18276 The following example shows how to use the @var{android-udev-rules}
18277 package so that the Android tool @command{adb} can detect devices
18278 without root privileges. It also details how to create the
18279 @code{adbusers} group, which is required for the proper functioning of
18280 the rules defined within the @code{android-udev-rules} package. To
18281 create such a group, we must define it both as part of the
18282 @code{supplementary-groups} of our @code{user-account} declaration, as
18283 well as in the @var{groups} of the @code{udev-rules-service} procedure.
18286 (use-modules (gnu packages android) ;for android-udev-rules
18287 (gnu system shadow) ;for user-group
18292 (users (cons (user-account
18294 (supplementary-groups
18295 '("adbusers" ;for adb
18296 "wheel" "netdev" "audio" "video")))))
18299 (cons (udev-rules-service 'android android-udev-rules
18300 #:groups '("adbusers"))
18301 %desktop-services)))
18304 @defvr {Scheme Variable} urandom-seed-service-type
18305 Save some entropy in @code{%random-seed-file} to seed @file{/dev/urandom}
18306 when rebooting. It also tries to seed @file{/dev/urandom} from
18307 @file{/dev/hwrng} while booting, if @file{/dev/hwrng} exists and is
18311 @defvr {Scheme Variable} %random-seed-file
18312 This is the name of the file where some random bytes are saved by
18313 @var{urandom-seed-service} to seed @file{/dev/urandom} when rebooting.
18314 It defaults to @file{/var/lib/random-seed}.
18319 @defvr {Scheme Variable} gpm-service-type
18320 This is the type of the service that runs GPM, the @dfn{general-purpose
18321 mouse daemon}, which provides mouse support to the Linux console. GPM
18322 allows users to use the mouse in the console, notably to select, copy,
18325 The value for services of this type must be a @code{gpm-configuration}
18326 (see below). This service is not part of @code{%base-services}.
18329 @deftp {Data Type} gpm-configuration
18330 Data type representing the configuration of GPM.
18333 @item @code{options} (default: @code{%default-gpm-options})
18334 Command-line options passed to @command{gpm}. The default set of
18335 options instruct @command{gpm} to listen to mouse events on
18336 @file{/dev/input/mice}. @xref{Command Line,,, gpm, gpm manual}, for
18339 @item @code{gpm} (default: @code{gpm})
18340 The GPM package to use.
18345 @anchor{guix-publish-service-type}
18346 @deffn {Scheme Variable} guix-publish-service-type
18347 This is the service type for @command{guix publish} (@pxref{Invoking
18348 guix publish}). Its value must be a @code{guix-publish-configuration}
18349 object, as described below.
18351 This assumes that @file{/etc/guix} already contains a signing key pair as
18352 created by @command{guix archive --generate-key} (@pxref{Invoking guix
18353 archive}). If that is not the case, the service will fail to start.
18356 @deftp {Data Type} guix-publish-configuration
18357 Data type representing the configuration of the @code{guix publish}
18361 @item @code{guix} (default: @code{guix})
18362 The Guix package to use.
18364 @item @code{port} (default: @code{80})
18365 The TCP port to listen for connections.
18367 @item @code{host} (default: @code{"localhost"})
18368 The host (and thus, network interface) to listen to. Use
18369 @code{"0.0.0.0"} to listen on all the network interfaces.
18371 @item @code{advertise?} (default: @code{#f})
18372 When true, advertise the service on the local network @i{via} the DNS-SD
18373 protocol, using Avahi.
18375 This allows neighboring Guix devices with discovery on (see
18376 @code{guix-configuration} above) to discover this @command{guix publish}
18377 instance and to automatically download substitutes from it.
18379 @item @code{compression} (default: @code{'(("gzip" 3) ("zstd" 3))})
18380 This is a list of compression method/level tuple used when compressing
18381 substitutes. For example, to compress all substitutes with @emph{both} lzip
18382 at level 7 and gzip at level 9, write:
18385 '(("lzip" 7) ("gzip" 9))
18388 Level 9 achieves the best compression ratio at the expense of increased CPU
18389 usage, whereas level 1 achieves fast compression. @xref{Invoking guix
18390 publish}, for more information on the available compression methods and
18391 the tradeoffs involved.
18393 An empty list disables compression altogether.
18395 @item @code{nar-path} (default: @code{"nar"})
18396 The URL path at which ``nars'' can be fetched. @xref{Invoking guix
18397 publish, @option{--nar-path}}, for details.
18399 @item @code{cache} (default: @code{#f})
18400 When it is @code{#f}, disable caching and instead generate archives on
18401 demand. Otherwise, this should be the name of a directory---e.g.,
18402 @code{"/var/cache/guix/publish"}---where @command{guix publish} caches
18403 archives and meta-data ready to be sent. @xref{Invoking guix publish,
18404 @option{--cache}}, for more information on the tradeoffs involved.
18406 @item @code{workers} (default: @code{#f})
18407 When it is an integer, this is the number of worker threads used for
18408 caching; when @code{#f}, the number of processors is used.
18409 @xref{Invoking guix publish, @option{--workers}}, for more information.
18411 @item @code{cache-bypass-threshold} (default: 10 MiB)
18412 When @code{cache} is true, this is the maximum size in bytes of a store
18413 item for which @command{guix publish} may bypass its cache in case of a
18414 cache miss. @xref{Invoking guix publish,
18415 @option{--cache-bypass-threshold}}, for more information.
18417 @item @code{ttl} (default: @code{#f})
18418 When it is an integer, this denotes the @dfn{time-to-live} in seconds
18419 of the published archives. @xref{Invoking guix publish, @option{--ttl}},
18420 for more information.
18422 @item @code{negative-ttl} (default: @code{#f})
18423 When it is an integer, this denotes the @dfn{time-to-live} in
18424 seconds for the negative lookups. @xref{Invoking guix publish,
18425 @option{--negative-ttl}}, for more information.
18429 @anchor{rngd-service}
18430 @deffn {Scheme Procedure} rngd-service [#:rng-tools @var{rng-tools}] @
18431 [#:device "/dev/hwrng"]
18432 Return a service that runs the @command{rngd} program from @var{rng-tools}
18433 to add @var{device} to the kernel's entropy pool. The service will fail if
18434 @var{device} does not exist.
18437 @anchor{pam-limits-service}
18438 @cindex session limits
18444 @cindex open file descriptors
18445 @deffn {Scheme Procedure} pam-limits-service [#:limits @code{'()}]
18447 Return a service that installs a configuration file for the
18448 @uref{http://linux-pam.org/Linux-PAM-html/sag-pam_limits.html,
18449 @code{pam_limits} module}. The procedure optionally takes a list of
18450 @code{pam-limits-entry} values, which can be used to specify
18451 @code{ulimit} limits and @code{nice} priority limits to user sessions.
18453 The following limits definition sets two hard and soft limits for all
18454 login sessions of users in the @code{realtime} group:
18457 (pam-limits-service
18459 (pam-limits-entry "@@realtime" 'both 'rtprio 99)
18460 (pam-limits-entry "@@realtime" 'both 'memlock 'unlimited)))
18463 The first entry increases the maximum realtime priority for
18464 non-privileged processes; the second entry lifts any restriction of the
18465 maximum address space that can be locked in memory. These settings are
18466 commonly used for real-time audio systems.
18468 Another useful example is raising the maximum number of open file
18469 descriptors that can be used:
18472 (pam-limits-service
18474 (pam-limits-entry "*" 'both 'nofile 100000)))
18477 In the above example, the asterisk means the limit should apply to any
18478 user. It is important to ensure the chosen value doesn't exceed the
18479 maximum system value visible in the @file{/proc/sys/fs/file-max} file,
18480 else the users would be prevented from login in. For more information
18481 about the Pluggable Authentication Module (PAM) limits, refer to the
18482 @samp{pam_limits} man page from the @code{linux-pam} package.
18485 @defvr {Scheme Variable} greetd-service-type
18486 @uref{https://git.sr.ht/~kennylevinsen/greetd, @code{greetd}} is a minimal and
18487 flexible login manager daemon, that makes no assumptions about what you
18490 If you can run it from your shell in a TTY, greetd can start it. If it
18491 can be taught to speak a simple JSON-based IPC protocol, then it can be
18494 @code{greetd-service-type} provides necessary infrastructure for logging
18495 in users, including:
18499 @code{greetd} PAM service
18502 Special variation of @code{pam-mount} to mount @code{XDG_RUNTIME_DIR}
18505 Here is example of switching from @code{mingetty-service-type} to
18506 @code{greetd-service-type}, and how different terminals could be:
18510 (modify-services %base-services
18511 ;; greetd-service-type provides "greetd" PAM service
18512 (delete login-service-type)
18513 ;; and can be used in place of mingetty-service-type
18514 (delete mingetty-service-type))
18516 (service greetd-service-type
18517 (greetd-configuration
18520 ;; we can make any terminal active by default
18521 (greetd-terminal-configuration (terminal-vt "1") (terminal-switch #t))
18522 ;; we can make environment without XDG_RUNTIME_DIR set
18523 ;; even provide our own environment variables
18524 (greetd-terminal-configuration
18526 (default-session-command
18527 (greetd-agreety-session
18528 (extra-env '(("MY_VAR" . "1")))
18530 ;; we can use different shell instead of default bash
18531 (greetd-terminal-configuration
18533 (default-session-command
18534 (greetd-agreety-session (command (file-append zsh "/bin/zsh")))))
18535 ;; we can use any other executable command as greeter
18536 (greetd-terminal-configuration
18538 (default-session-command (program-file "my-noop-greeter" #~(exit))))
18539 (greetd-terminal-configuration (terminal-vt "5"))
18540 (greetd-terminal-configuration (terminal-vt "6"))))))
18541 ;; mingetty-service-type can be used in parallel
18542 ;; if needed to do so, do not (delete login-service-type)
18543 ;; as illustrated above
18544 #| (service mingetty-service-type (mingetty-configuration (tty "tty8"))) |#))
18548 @deftp {Data Type} greetd-configuration
18549 Configuration record for the @code{greetd-service-type}.
18553 A file-like object containing the ``message of the day''.
18555 @item @code{allow-empty-passwords?} (default: @code{#t})
18556 Allow empty passwords by default so that first-time users can log in when
18557 the 'root' account has just been created.
18559 @item @code{terminals} (default: @code{'()})
18560 List of @code{greetd-terminal-configuration} per terminal for which
18561 @code{greetd} should be started.
18565 @deftp {Data Type} greetd-terminal-configuration
18566 Configuration record for per terminal greetd daemon service.
18569 @item @code{greetd} (default: @code{greetd})
18570 The greetd package to use.
18572 @item @code{config-file-name}
18573 Configuration file name to use for greetd daemon. Generally, autogenerated
18574 derivation based on @code{terminal-vt} value.
18576 @item @code{log-file-name}
18577 Log file name to use for greetd daemon. Generally, autogenerated
18578 name based on @code{terminal-vt} value.
18580 @item @code{terminal-vt} (default: @samp{"7"})
18581 The VT to run on. Use of a specific VT with appropriate conflict avoidance
18584 @item @code{terminal-switch} (default: @code{#f})
18585 Make this terminal active on start of @code{greetd}.
18587 @item @code{default-session-user} (default: @samp{"greeter"})
18588 The user to use for running the greeter.
18590 @item @code{default-session-command} (default: @code{(greetd-agreety-session)})
18591 Can be either instance of @code{greetd-agreety-session} configuration or
18592 @code{gexp->script} like object to use as greeter.
18597 @deftp {Data Type} greetd-agreety-session
18598 Configuration record for the agreety greetd greeter.
18601 @item @code{agreety} (default: @code{greetd})
18602 The package with @command{/bin/agreety} command.
18604 @item @code{command} (default: @code{(file-append bash "/bin/bash")})
18605 Command to be started by @command{/bin/agreety} on successful login.
18607 @item @code{command-args} (default: @code{'("-l")})
18608 Command arguments to pass to command.
18610 @item @code{extra-env} (default: @code{'()})
18611 Extra environment variables to set on login.
18613 @item @code{xdg-env?} (default: @code{#t})
18614 If true @code{XDG_RUNTIME_DIR} and @code{XDG_SESSION_TYPE} will be set
18615 before starting command. One should note that, @code{extra-env} variables
18616 are set right after mentioned variables, so that they can be overriden.
18621 @node Scheduled Job Execution
18622 @subsection Scheduled Job Execution
18626 @cindex scheduling jobs
18627 The @code{(gnu services mcron)} module provides an interface to
18628 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
18629 mcron, GNU@tie{}mcron}). GNU@tie{}mcron is similar to the traditional
18630 Unix @command{cron} daemon; the main difference is that it is
18631 implemented in Guile Scheme, which provides a lot of flexibility when
18632 specifying the scheduling of jobs and their actions.
18634 The example below defines an operating system that runs the
18635 @command{updatedb} (@pxref{Invoking updatedb,,, find, Finding Files})
18636 and the @command{guix gc} commands (@pxref{Invoking guix gc}) daily, as
18637 well as the @command{mkid} command on behalf of an unprivileged user
18638 (@pxref{mkid invocation,,, idutils, ID Database Utilities}). It uses
18639 gexps to introduce job definitions that are passed to mcron
18640 (@pxref{G-Expressions}).
18643 (use-modules (guix) (gnu) (gnu services mcron))
18644 (use-package-modules base idutils)
18646 (define updatedb-job
18647 ;; Run 'updatedb' at 3AM every day. Here we write the
18648 ;; job's action as a Scheme procedure.
18649 #~(job '(next-hour '(3))
18651 (execl (string-append #$findutils "/bin/updatedb")
18653 "--prunepaths=/tmp /var/tmp /gnu/store"))
18656 (define garbage-collector-job
18657 ;; Collect garbage 5 minutes after midnight every day.
18658 ;; The job's action is a shell command.
18659 #~(job "5 0 * * *" ;Vixie cron syntax
18662 (define idutils-job
18663 ;; Update the index database as user "charlie" at 12:15PM
18664 ;; and 19:15PM. This runs from the user's home directory.
18665 #~(job '(next-minute-from (next-hour '(12 19)) '(15))
18666 (string-append #$idutils "/bin/mkid src")
18672 ;; %BASE-SERVICES already includes an instance of
18673 ;; 'mcron-service-type', which we extend with additional
18674 ;; jobs using 'simple-service'.
18675 (services (cons (simple-service 'my-cron-jobs
18677 (list garbage-collector-job
18684 When providing the action of a job specification as a procedure, you
18685 should provide an explicit name for the job via the optional 3rd
18686 argument as done in the @code{updatedb-job} example above. Otherwise,
18687 the job would appear as ``Lambda function'' in the output of
18688 @command{herd schedule mcron}, which is not nearly descriptive enough!
18691 For more complex jobs defined in Scheme where you need control over the top
18692 level, for instance to introduce a @code{use-modules} form, you can move your
18693 code to a separate program using the @code{program-file} procedure of the
18694 @code{(guix gexp)} module (@pxref{G-Expressions}). The example below
18698 (define %battery-alert-job
18699 ;; Beep when the battery percentage falls below %MIN-LEVEL.
18701 '(next-minute (range 0 60 1))
18703 "battery-alert.scm"
18704 (with-imported-modules (source-module-closure
18705 '((guix build utils)))
18707 (use-modules (guix build utils)
18710 (ice-9 textual-ports)
18713 (define %min-level 20)
18715 (setenv "LC_ALL" "C") ;ensure English output
18716 (and-let* ((input-pipe (open-pipe*
18718 #$(file-append acpi "/bin/acpi")))
18719 (output (get-string-all input-pipe))
18720 (m (string-match "Discharging, ([0-9]+)%" output))
18721 (level (string->number (match:substring m 1)))
18722 ((< level %min-level)))
18723 (format #t "warning: Battery level is low (~a%)~%" level)
18724 (invoke #$(file-append beep "/bin/beep") "-r5")))))))
18727 @xref{Guile Syntax, mcron job specifications,, mcron, GNU@tie{}mcron},
18728 for more information on mcron job specifications. Below is the
18729 reference of the mcron service.
18731 On a running system, you can use the @code{schedule} action of the service to
18732 visualize the mcron jobs that will be executed next:
18735 # herd schedule mcron
18739 The example above lists the next five tasks that will be executed, but you can
18740 also specify the number of tasks to display:
18743 # herd schedule mcron 10
18746 @defvr {Scheme Variable} mcron-service-type
18747 This is the type of the @code{mcron} service, whose value is an
18748 @code{mcron-configuration} object.
18750 This service type can be the target of a service extension that provides
18751 additional job specifications (@pxref{Service Composition}). In other
18752 words, it is possible to define services that provide additional mcron
18756 @deftp {Data Type} mcron-configuration
18757 Data type representing the configuration of mcron.
18760 @item @code{mcron} (default: @var{mcron})
18761 The mcron package to use.
18764 This is a list of gexps (@pxref{G-Expressions}), where each gexp
18765 corresponds to an mcron job specification (@pxref{Syntax, mcron job
18766 specifications,, mcron, GNU@tie{}mcron}).
18772 @subsection Log Rotation
18775 @cindex log rotation
18777 Log files such as those found in @file{/var/log} tend to grow endlessly,
18778 so it's a good idea to @dfn{rotate} them once in a while---i.e., archive
18779 their contents in separate files, possibly compressed. The @code{(gnu
18780 services admin)} module provides an interface to GNU@tie{}Rot[t]log, a
18781 log rotation tool (@pxref{Top,,, rottlog, GNU Rot[t]log Manual}).
18783 This service is part of @code{%base-services}, and thus enabled by
18784 default, with the default settings, for commonly encountered log files.
18785 The example below shows how to extend it with an additional
18786 @dfn{rotation}, should you need to do that (usually, services that
18787 produce log files already take care of that):
18790 (use-modules (guix) (gnu))
18791 (use-service-modules admin)
18793 (define my-log-files
18794 ;; Log files that I want to rotate.
18795 '("/var/log/something.log" "/var/log/another.log"))
18799 (services (cons (simple-service 'rotate-my-stuff
18800 rottlog-service-type
18801 (list (log-rotation
18803 (files my-log-files))))
18807 @defvr {Scheme Variable} rottlog-service-type
18808 This is the type of the Rottlog service, whose value is a
18809 @code{rottlog-configuration} object.
18811 Other services can extend this one with new @code{log-rotation} objects
18812 (see below), thereby augmenting the set of files to be rotated.
18814 This service type can define mcron jobs (@pxref{Scheduled Job
18815 Execution}) to run the rottlog service.
18818 @deftp {Data Type} rottlog-configuration
18819 Data type representing the configuration of rottlog.
18822 @item @code{rottlog} (default: @code{rottlog})
18823 The Rottlog package to use.
18825 @item @code{rc-file} (default: @code{(file-append rottlog "/etc/rc")})
18826 The Rottlog configuration file to use (@pxref{Mandatory RC Variables,,,
18827 rottlog, GNU Rot[t]log Manual}).
18829 @item @code{rotations} (default: @code{%default-rotations})
18830 A list of @code{log-rotation} objects as defined below.
18833 This is a list of gexps where each gexp corresponds to an mcron job
18834 specification (@pxref{Scheduled Job Execution}).
18838 @deftp {Data Type} log-rotation
18839 Data type representing the rotation of a group of log files.
18841 Taking an example from the Rottlog manual (@pxref{Period Related File
18842 Examples,,, rottlog, GNU Rot[t]log Manual}), a log rotation might be
18848 (files '("/var/log/apache/*"))
18849 (options '("storedir apache-archives"
18855 The list of fields is as follows:
18858 @item @code{frequency} (default: @code{'weekly})
18859 The log rotation frequency, a symbol.
18862 The list of files or file glob patterns to rotate.
18864 @vindex %default-log-rotation-options
18865 @item @code{options} (default: @code{%default-log-rotation-options})
18866 The list of rottlog options for this rotation (@pxref{Configuration
18867 parameters,,, rottlog, GNU Rot[t]log Manual}).
18869 @item @code{post-rotate} (default: @code{#f})
18870 Either @code{#f} or a gexp to execute once the rotation has completed.
18874 @defvr {Scheme Variable} %default-rotations
18875 Specifies weekly rotation of @code{%rotated-files} and of
18876 @file{/var/log/guix-daemon.log}.
18879 @defvr {Scheme Variable} %rotated-files
18880 The list of syslog-controlled files to be rotated. By default it is:
18881 @code{'("/var/log/messages" "/var/log/secure" "/var/log/debug" \
18882 "/var/log/maillog")}.
18885 Some log files just need to be deleted periodically once they are old,
18886 without any other criterion and without any archival step. This is the
18887 case of build logs stored by @command{guix-daemon} under
18888 @file{/var/log/guix/drvs} (@pxref{Invoking guix-daemon}). The
18889 @code{log-cleanup} service addresses this use case. For example,
18890 @code{%base-services} (@pxref{Base Services}) includes the following:
18893 ;; Periodically delete old build logs.
18894 (service log-cleanup-service-type
18895 (log-cleanup-configuration
18896 (directory "/var/log/guix/drvs")))
18899 That ensures build logs do not accumulate endlessly.
18901 @defvr {Scheme Variable} log-cleanup-service-type
18902 This is the type of the service to delete old logs. Its value must be a
18903 @code{log-cleanup-configuration} record as described below.
18906 @deftp {Data Type} log-cleanup-configuration
18907 Data type representing the log cleanup configuration
18910 @item @code{directory}
18911 Name of the directory containing log files.
18913 @item @code{expiry} (default: @code{(* 6 30 24 3600)})
18914 Age in seconds after which a file is subject to deletion (six months by
18917 @item @code{schedule} (default: @code{"30 12 01,08,15,22 * *"})
18918 String or gexp denoting the corresponding mcron job schedule
18919 (@pxref{Scheduled Job Execution}).
18923 @cindex logging, anonymization
18924 @subheading Anonip Service
18926 Anonip is a privacy filter that removes IP address from web server logs.
18927 This service creates a FIFO and filters any written lines with anonip
18928 before writing the filtered log to a target file.
18930 The following example sets up the FIFO
18931 @file{/var/run/anonip/https.access.log} and writes the filtered log file
18932 @file{/var/log/anonip/https.access.log}.
18935 (service anonip-service-type
18936 (anonip-configuration
18937 (input "/var/run/anonip/https.access.log")
18938 (output "/var/log/anonip/https.access.log")))
18941 Configure your web server to write its logs to the FIFO at
18942 @file{/var/run/anonip/https.access.log} and collect the anonymized log
18943 file at @file{/var/web-logs/https.access.log}.
18945 @deftp {Data Type} anonip-configuration
18946 This data type represents the configuration of anonip.
18947 It has the following parameters:
18950 @item @code{anonip} (default: @code{anonip})
18951 The anonip package to use.
18954 The file name of the input log file to process. The service creates a
18955 FIFO of this name. The web server should write its logs to this FIFO.
18957 @item @code{output}
18958 The file name of the processed log file.
18961 The following optional settings may be provided:
18964 @item @code{skip-private?}
18965 When @code{#true} do not mask addresses in private ranges.
18967 @item @code{column}
18968 A 1-based indexed column number. Assume IP address is in the specified
18969 column (default is 1).
18971 @item @code{replacement}
18972 Replacement string in case address parsing fails, e.g. @code{"0.0.0.0"}.
18974 @item @code{ipv4mask}
18975 Number of bits to mask in IPv4 addresses.
18977 @item @code{ipv6mask}
18978 Number of bits to mask in IPv6 addresses.
18980 @item @code{increment}
18981 Increment the IP address by the given number. By default this is zero.
18983 @item @code{delimiter}
18984 Log delimiter string.
18987 Regular expression for detecting IP addresses. Use this instead of @code{column}.
18992 @node Networking Setup
18993 @subsection Networking Setup
18995 The @code{(gnu services networking)} module provides services to
18996 configure network interfaces and set up networking on your machine.
18997 Those services provide different ways for you to set up your machine: by
18998 declaring a static network configuration, by running a Dynamic Host
18999 Configuration Protocol (DHCP) client, or by running daemons such as
19000 NetworkManager and Connman that automate the whole process,
19001 automatically adapt to connectivity changes, and provide a high-level
19004 On a laptop, NetworkManager and Connman are by far the most convenient
19005 options, which is why the default desktop services include
19006 NetworkManager (@pxref{Desktop Services, @code{%desktop-services}}).
19007 For a server, or for a virtual machine or a container, static network
19008 configuration or a simple DHCP client are often more appropriate.
19010 This section describes the various network setup services available,
19011 starting with static network configuration.
19013 @defvr {Scheme Variable} static-networking-service-type
19014 This is the type for statically-configured network interfaces. Its
19015 value must be a list of @code{static-networking} records. Each of them
19016 declares a set of @dfn{addresses}, @dfn{routes}, and @dfn{links}, as
19019 @cindex network interface controller (NIC)
19020 @cindex NIC, networking interface controller
19021 Here is the simplest configuration, with only one network interface
19022 controller (NIC) and only IPv4 connectivity:
19025 ;; Static networking for one NIC, IPv4-only.
19026 (service static-networking-service-type
19027 (list (static-networking
19029 (list (network-address
19031 (value "10.0.2.15/24"))))
19033 (list (network-route
19034 (destination "default")
19035 (gateway "10.0.2.2"))))
19036 (name-servers '("10.0.2.3")))))
19039 The snippet above can be added to the @code{services} field of your
19040 operating system configuration (@pxref{Using the Configuration System}).
19041 It will configure your machine to have 10.0.2.15 as its IP address, with
19042 a 24-bit netmask for the local network---meaning that any 10.0.2.@var{x}
19043 address is on the local area network (LAN). Traffic to addresses
19044 outside the local network is routed @i{via} 10.0.2.2. Host names are
19045 resolved by sending domain name system (DNS) queries to 10.0.2.3.
19048 @deftp {Data Type} static-networking
19049 This is the data type representing a static network configuration.
19051 As an example, here is how you would declare the configuration of a
19052 machine with a single network interface controller (NIC) available as
19053 @code{eno1}, and with one IPv4 and one IPv6 address:
19056 ;; Network configuration for one NIC, IPv4 + IPv6.
19058 (addresses (list (network-address
19060 (value "10.0.2.15/24"))
19063 (value "2001:123:4567:101::1/64"))))
19064 (routes (list (network-route
19065 (destination "default")
19066 (gateway "10.0.2.2"))
19068 (destination "default")
19069 (gateway "2020:321:4567:42::1"))))
19070 (name-servers '("10.0.2.3")))
19073 If you are familiar with the @command{ip} command of the
19074 @uref{https://wiki.linuxfoundation.org/networking/iproute2,
19075 @code{iproute2} package} found on Linux-based systems, the declaration
19076 above is equivalent to typing:
19079 ip address add 10.0.2.15/24 dev eno1
19080 ip address add 2001:123:4567:101::1/64 dev eno1
19081 ip route add default via inet 10.0.2.2
19082 ip route add default via inet6 2020:321:4567:42::1
19085 Run @command{man 8 ip} for more info. Venerable GNU/Linux users will
19086 certainly know how to do it with @command{ifconfig} and @command{route},
19087 but we'll spare you that.
19089 The available fields of this data type are as follows:
19092 @item @code{addresses}
19093 @itemx @code{links} (default: @code{'()})
19094 @itemx @code{routes} (default: @code{'()})
19095 The list of @code{network-address}, @code{network-link}, and
19096 @code{network-route} records for this network (see below).
19098 @item @code{name-servers} (default: @code{'()})
19099 The list of IP addresses (strings) of domain name servers. These IP
19100 addresses go to @file{/etc/resolv.conf}.
19102 @item @code{provision} (default: @code{'(networking)})
19103 If true, this should be a list of symbols for the Shepherd service
19104 corresponding to this network configuration.
19106 @item @code{requirement} (default @code{'()})
19107 The list of Shepherd services depended on.
19111 @deftp {Data Type} network-address
19112 This is the data type representing the IP address of a network
19117 The name of the network interface for this address---e.g.,
19121 The actual IP address and network mask, in
19122 @uref{https://en.wikipedia.org/wiki/CIDR#CIDR_notation, @acronym{CIDR,
19123 Classless Inter-Domain Routing} notation}, as a string.
19125 For example, @code{"10.0.2.15/24"} denotes IPv4 address 10.0.2.15 on a
19126 24-bit sub-network---all 10.0.2.@var{x} addresses are on the same local
19130 Whether @code{value} denotes an IPv6 address. By default this is
19131 automatically determined.
19135 @deftp {Data Type} network-route
19136 This is the data type representing a network route.
19139 @item @code{destination}
19140 The route destination (a string), either an IP address or
19141 @code{"default"} to denote the default route.
19143 @item @code{source} (default: @code{#f})
19146 @item @code{device} (default: @code{#f})
19147 The device used for this route---e.g., @code{"eno2"}.
19149 @item @code{ipv6?} (default: auto)
19150 Whether this is an IPv6 route. By default this is automatically
19151 determined based on @code{destination} or @code{gateway}.
19153 @item @code{gateway} (default: @code{#f})
19154 IP address (a string) through which traffic is routed.
19158 @deftp {Data Type} network-link
19159 Data type for a network link (@pxref{Link,,, guile-netlink,
19160 Guile-Netlink Manual}).
19164 The name of the link---e.g., @code{"v0p0"}.
19167 A symbol denoting the type of the link---e.g., @code{'veth}.
19170 List of arguments for this type of link.
19174 @cindex loopback device
19175 @defvr {Scheme Variable} %loopback-static-networking
19176 This is the @code{static-networking} record representing the ``loopback
19177 device'', @code{lo}, for IP addresses 127.0.0.1 and ::1, and providing
19178 the @code{loopback} Shepherd service.
19181 @cindex networking, with QEMU
19182 @cindex QEMU, networking
19183 @defvr {Scheme Variable} %qemu-static-networking
19184 This is the @code{static-networking} record representing network setup
19185 when using QEMU's user-mode network stack on @code{eth0} (@pxref{Using
19186 the user mode network stack,,, QEMU, QEMU Documentation}).
19189 @cindex DHCP, networking service
19190 @defvr {Scheme Variable} dhcp-client-service-type
19191 This is the type of services that run @var{dhcp}, a Dynamic Host Configuration
19192 Protocol (DHCP) client, on all the non-loopback network interfaces. Its value
19193 is the DHCP client package to use, @code{isc-dhcp} by default.
19196 @cindex NetworkManager
19198 @defvr {Scheme Variable} network-manager-service-type
19199 This is the service type for the
19200 @uref{https://wiki.gnome.org/Projects/NetworkManager, NetworkManager}
19201 service. The value for this service type is a
19202 @code{network-manager-configuration} record.
19204 This service is part of @code{%desktop-services} (@pxref{Desktop
19208 @deftp {Data Type} network-manager-configuration
19209 Data type representing the configuration of NetworkManager.
19212 @item @code{network-manager} (default: @code{network-manager})
19213 The NetworkManager package to use.
19215 @item @code{dns} (default: @code{"default"})
19216 Processing mode for DNS, which affects how NetworkManager uses the
19217 @code{resolv.conf} configuration file.
19221 NetworkManager will update @code{resolv.conf} to reflect the nameservers
19222 provided by currently active connections.
19225 NetworkManager will run @code{dnsmasq} as a local caching nameserver, using a
19226 @dfn{conditional forwarding} configuration if you are connected to a VPN, and
19227 then update @code{resolv.conf} to point to the local nameserver.
19229 With this setting, you can share your network connection. For example when
19230 you want to share your network connection to another laptop @i{via} an
19231 Ethernet cable, you can open @command{nm-connection-editor} and configure the
19232 Wired connection's method for IPv4 and IPv6 to be ``Shared to other computers''
19233 and reestablish the connection (or reboot).
19235 You can also set up a @dfn{host-to-guest connection} to QEMU VMs
19236 (@pxref{Installing Guix in a VM}). With a host-to-guest connection, you can
19237 e.g.@: access a Web server running on the VM (@pxref{Web Services}) from a Web
19238 browser on your host system, or connect to the VM @i{via} SSH
19239 (@pxref{Networking Services, @code{openssh-service-type}}). To set up a
19240 host-to-guest connection, run this command once:
19243 nmcli connection add type tun \
19244 connection.interface-name tap0 \
19245 tun.mode tap tun.owner $(id -u) \
19246 ipv4.method shared \
19247 ipv4.addresses 172.28.112.1/24
19250 Then each time you launch your QEMU VM (@pxref{Running Guix in a VM}), pass
19251 @option{-nic tap,ifname=tap0,script=no,downscript=no} to
19252 @command{qemu-system-...}.
19255 NetworkManager will not modify @code{resolv.conf}.
19258 @item @code{vpn-plugins} (default: @code{'()})
19259 This is the list of available plugins for virtual private networks
19260 (VPNs). An example of this is the @code{network-manager-openvpn}
19261 package, which allows NetworkManager to manage VPNs @i{via} OpenVPN.
19267 @deffn {Scheme Variable} connman-service-type
19268 This is the service type to run @url{https://01.org/connman,Connman},
19269 a network connection manager.
19271 Its value must be an
19272 @code{connman-configuration} record as in this example:
19275 (service connman-service-type
19276 (connman-configuration
19277 (disable-vpn? #t)))
19280 See below for details about @code{connman-configuration}.
19283 @deftp {Data Type} connman-configuration
19284 Data Type representing the configuration of connman.
19287 @item @code{connman} (default: @var{connman})
19288 The connman package to use.
19290 @item @code{disable-vpn?} (default: @code{#f})
19291 When true, disable connman's vpn plugin.
19295 @cindex WPA Supplicant
19296 @defvr {Scheme Variable} wpa-supplicant-service-type
19297 This is the service type to run @url{https://w1.fi/wpa_supplicant/,WPA
19298 supplicant}, an authentication daemon required to authenticate against
19299 encrypted WiFi or ethernet networks.
19302 @deftp {Data Type} wpa-supplicant-configuration
19303 Data type representing the configuration of WPA Supplicant.
19305 It takes the following parameters:
19308 @item @code{wpa-supplicant} (default: @code{wpa-supplicant})
19309 The WPA Supplicant package to use.
19311 @item @code{requirement} (default: @code{'(user-processes loopback syslogd)}
19312 List of services that should be started before WPA Supplicant starts.
19314 @item @code{dbus?} (default: @code{#t})
19315 Whether to listen for requests on D-Bus.
19317 @item @code{pid-file} (default: @code{"/var/run/wpa_supplicant.pid"})
19318 Where to store the PID file.
19320 @item @code{interface} (default: @code{#f})
19321 If this is set, it must specify the name of a network interface that
19322 WPA supplicant will control.
19324 @item @code{config-file} (default: @code{#f})
19325 Optional configuration file to use.
19327 @item @code{extra-options} (default: @code{'()})
19328 List of additional command-line arguments to pass to the daemon.
19332 @cindex ModemManager
19333 Some networking devices such as modems require special care, and this is
19334 what the services below focus on.
19336 @defvr {Scheme Variable} modem-manager-service-type
19337 This is the service type for the
19338 @uref{https://wiki.gnome.org/Projects/ModemManager, ModemManager}
19339 service. The value for this service type is a
19340 @code{modem-manager-configuration} record.
19342 This service is part of @code{%desktop-services} (@pxref{Desktop
19346 @deftp {Data Type} modem-manager-configuration
19347 Data type representing the configuration of ModemManager.
19350 @item @code{modem-manager} (default: @code{modem-manager})
19351 The ModemManager package to use.
19356 @cindex USB_ModeSwitch
19357 @cindex Modeswitching
19359 @defvr {Scheme Variable} usb-modeswitch-service-type
19360 This is the service type for the
19361 @uref{https://www.draisberghof.de/usb_modeswitch/, USB_ModeSwitch}
19362 service. The value for this service type is
19363 a @code{usb-modeswitch-configuration} record.
19365 When plugged in, some USB modems (and other USB devices) initially present
19366 themselves as a read-only storage medium and not as a modem. They need to be
19367 @dfn{modeswitched} before they are usable. The USB_ModeSwitch service type
19368 installs udev rules to automatically modeswitch these devices when they are
19371 This service is part of @code{%desktop-services} (@pxref{Desktop
19375 @deftp {Data Type} usb-modeswitch-configuration
19376 Data type representing the configuration of USB_ModeSwitch.
19379 @item @code{usb-modeswitch} (default: @code{usb-modeswitch})
19380 The USB_ModeSwitch package providing the binaries for modeswitching.
19382 @item @code{usb-modeswitch-data} (default: @code{usb-modeswitch-data})
19383 The package providing the device data and udev rules file used by
19386 @item @code{config-file} (default: @code{#~(string-append #$usb-modeswitch:dispatcher "/etc/usb_modeswitch.conf")})
19387 Which config file to use for the USB_ModeSwitch dispatcher. By default the
19388 config file shipped with USB_ModeSwitch is used which disables logging to
19389 @file{/var/log} among other default settings. If set to @code{#f}, no config
19396 @node Networking Services
19397 @subsection Networking Services
19399 The @code{(gnu services networking)} module discussed in the previous
19400 section provides services for more advanced setups: providing a DHCP
19401 service for others to use, filtering packets with iptables or nftables,
19402 running a WiFi access point with @command{hostapd}, running the
19403 @command{inetd} ``superdaemon'', and more. This section describes
19406 @deffn {Scheme Procedure} dhcpd-service-type
19407 This type defines a service that runs a DHCP daemon. To create a
19408 service of this type, you must supply a @code{<dhcpd-configuration>}.
19412 (service dhcpd-service-type
19413 (dhcpd-configuration
19414 (config-file (local-file "my-dhcpd.conf"))
19415 (interfaces '("enp0s25"))))
19419 @deftp {Data Type} dhcpd-configuration
19421 @item @code{package} (default: @code{isc-dhcp})
19422 The package that provides the DHCP daemon. This package is expected to
19423 provide the daemon at @file{sbin/dhcpd} relative to its output
19424 directory. The default package is the
19425 @uref{https://www.isc.org/products/DHCP, ISC's DHCP server}.
19426 @item @code{config-file} (default: @code{#f})
19427 The configuration file to use. This is required. It will be passed to
19428 @code{dhcpd} via its @code{-cf} option. This may be any ``file-like''
19429 object (@pxref{G-Expressions, file-like objects}). See @code{man
19430 dhcpd.conf} for details on the configuration file syntax.
19431 @item @code{version} (default: @code{"4"})
19432 The DHCP version to use. The ISC DHCP server supports the values ``4'',
19433 ``6'', and ``4o6''. These correspond to the @code{dhcpd} program
19434 options @code{-4}, @code{-6}, and @code{-4o6}. See @code{man dhcpd} for
19436 @item @code{run-directory} (default: @code{"/run/dhcpd"})
19437 The run directory to use. At service activation time, this directory
19438 will be created if it does not exist.
19439 @item @code{pid-file} (default: @code{"/run/dhcpd/dhcpd.pid"})
19440 The PID file to use. This corresponds to the @code{-pf} option of
19441 @code{dhcpd}. See @code{man dhcpd} for details.
19442 @item @code{interfaces} (default: @code{'()})
19443 The names of the network interfaces on which dhcpd should listen for
19444 broadcasts. If this list is not empty, then its elements (which must be
19445 strings) will be appended to the @code{dhcpd} invocation when starting
19446 the daemon. It may not be necessary to explicitly specify any
19447 interfaces here; see @code{man dhcpd} for details.
19451 @cindex hostapd service, for Wi-Fi access points
19452 @cindex Wi-Fi access points, hostapd service
19453 @defvr {Scheme Variable} hostapd-service-type
19454 This is the service type to run the @uref{https://w1.fi/hostapd/,
19455 hostapd} daemon to set up WiFi (IEEE 802.11) access points and
19456 authentication servers. Its associated value must be a
19457 @code{hostapd-configuration} as shown below:
19460 ;; Use wlan1 to run the access point for "My Network".
19461 (service hostapd-service-type
19462 (hostapd-configuration
19463 (interface "wlan1")
19464 (ssid "My Network")
19469 @deftp {Data Type} hostapd-configuration
19470 This data type represents the configuration of the hostapd service, with
19471 the following fields:
19474 @item @code{package} (default: @code{hostapd})
19475 The hostapd package to use.
19477 @item @code{interface} (default: @code{"wlan0"})
19478 The network interface to run the WiFi access point.
19481 The SSID (@dfn{service set identifier}), a string that identifies this
19484 @item @code{broadcast-ssid?} (default: @code{#t})
19485 Whether to broadcast this SSID.
19487 @item @code{channel} (default: @code{1})
19488 The WiFi channel to use.
19490 @item @code{driver} (default: @code{"nl80211"})
19491 The driver interface type. @code{"nl80211"} is used with all Linux
19492 mac80211 drivers. Use @code{"none"} if building hostapd as a standalone
19493 RADIUS server that does # not control any wireless/wired driver.
19495 @item @code{extra-settings} (default: @code{""})
19496 Extra settings to append as-is to the hostapd configuration file. See
19497 @uref{https://w1.fi/cgit/hostap/plain/hostapd/hostapd.conf} for the
19498 configuration file reference.
19502 @defvr {Scheme Variable} simulated-wifi-service-type
19503 This is the type of a service to simulate WiFi networking, which can be
19504 useful in virtual machines for testing purposes. The service loads the
19506 @uref{https://www.kernel.org/doc/html/latest/networking/mac80211_hwsim/mac80211_hwsim.html,
19507 @code{mac80211_hwsim} module} and starts hostapd to create a pseudo WiFi
19508 network that can be seen on @code{wlan0}, by default.
19510 The service's value is a @code{hostapd-configuration} record.
19515 @defvr {Scheme Variable} iptables-service-type
19516 This is the service type to set up an iptables configuration. iptables is a
19517 packet filtering framework supported by the Linux kernel. This service
19518 supports configuring iptables for both IPv4 and IPv6. A simple example
19519 configuration rejecting all incoming connections except those to the ssh port
19523 (service iptables-service-type
19524 (iptables-configuration
19525 (ipv4-rules (plain-file "iptables.rules" "*filter
19529 -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
19530 -A INPUT -p tcp --dport 22 -j ACCEPT
19531 -A INPUT -j REJECT --reject-with icmp-port-unreachable
19534 (ipv6-rules (plain-file "ip6tables.rules" "*filter
19538 -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
19539 -A INPUT -p tcp --dport 22 -j ACCEPT
19540 -A INPUT -j REJECT --reject-with icmp6-port-unreachable
19546 @deftp {Data Type} iptables-configuration
19547 The data type representing the configuration of iptables.
19550 @item @code{iptables} (default: @code{iptables})
19551 The iptables package that provides @code{iptables-restore} and
19552 @code{ip6tables-restore}.
19553 @item @code{ipv4-rules} (default: @code{%iptables-accept-all-rules})
19554 The iptables rules to use. It will be passed to @code{iptables-restore}.
19555 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
19557 @item @code{ipv6-rules} (default: @code{%iptables-accept-all-rules})
19558 The ip6tables rules to use. It will be passed to @code{ip6tables-restore}.
19559 This may be any ``file-like'' object (@pxref{G-Expressions, file-like
19565 @defvr {Scheme Variable} nftables-service-type
19566 This is the service type to set up a nftables configuration. nftables is a
19567 netfilter project that aims to replace the existing iptables, ip6tables,
19568 arptables and ebtables framework. It provides a new packet filtering
19569 framework, a new user-space utility @command{nft}, and a compatibility layer
19570 for iptables. This service comes with a default ruleset
19571 @code{%default-nftables-ruleset} that rejecting all incoming connections
19572 except those to the ssh port 22. To use it, simply write:
19575 (service nftables-service-type)
19579 @deftp {Data Type} nftables-configuration
19580 The data type representing the configuration of nftables.
19583 @item @code{package} (default: @code{nftables})
19584 The nftables package that provides @command{nft}.
19585 @item @code{ruleset} (default: @code{%default-nftables-ruleset})
19586 The nftables ruleset to use. This may be any ``file-like'' object
19587 (@pxref{G-Expressions, file-like objects}).
19591 @cindex NTP (Network Time Protocol), service
19592 @cindex ntpd, service for the Network Time Protocol daemon
19593 @cindex real time clock
19594 @defvr {Scheme Variable} ntp-service-type
19595 This is the type of the service running the @uref{https://www.ntp.org,
19596 Network Time Protocol (NTP)} daemon, @command{ntpd}. The daemon will keep the
19597 system clock synchronized with that of the specified NTP servers.
19599 The value of this service is an @code{ntpd-configuration} object, as described
19603 @deftp {Data Type} ntp-configuration
19604 This is the data type for the NTP service configuration.
19607 @item @code{servers} (default: @code{%ntp-servers})
19608 This is the list of servers (@code{<ntp-server>} records) with which
19609 @command{ntpd} will be synchronized. See the @code{ntp-server} data type
19612 @item @code{allow-large-adjustment?} (default: @code{#t})
19613 This determines whether @command{ntpd} is allowed to make an initial
19614 adjustment of more than 1,000 seconds.
19616 @item @code{ntp} (default: @code{ntp})
19617 The NTP package to use.
19621 @defvr {Scheme Variable} %ntp-servers
19622 List of host names used as the default NTP servers. These are servers of the
19623 @uref{https://www.ntppool.org/en/, NTP Pool Project}.
19626 @deftp {Data Type} ntp-server
19627 The data type representing the configuration of a NTP server.
19630 @item @code{type} (default: @code{'server})
19631 The type of the NTP server, given as a symbol. One of @code{'pool},
19632 @code{'server}, @code{'peer}, @code{'broadcast} or @code{'manycastclient}.
19634 @item @code{address}
19635 The address of the server, as a string.
19637 @item @code{options}
19638 NTPD options to use with that specific server, given as a list of option names
19639 and/or of option names and values tuples. The following example define a server
19640 to use with the options @option{iburst} and @option{prefer}, as well as
19641 @option{version} 3 and a @option{maxpoll} time of 16 seconds.
19646 (address "some.ntp.server.org")
19647 (options `(iburst (version 3) (maxpoll 16) prefer))))
19653 @deffn {Scheme Procedure} openntpd-service-type
19654 Run the @command{ntpd}, the Network Time Protocol (NTP) daemon, as implemented
19655 by @uref{http://www.openntpd.org, OpenNTPD}. The daemon will keep the system
19656 clock synchronized with that of the given servers.
19660 openntpd-service-type
19661 (openntpd-configuration
19662 (listen-on '("127.0.0.1" "::1"))
19663 (sensor '("udcf0 correction 70000"))
19664 (constraint-from '("www.gnu.org"))
19665 (constraints-from '("https://www.google.com/"))))
19670 @defvr {Scheme Variable} %openntpd-servers
19671 This variable is a list of the server addresses defined in
19672 @code{%ntp-servers}.
19675 @deftp {Data Type} openntpd-configuration
19677 @item @code{openntpd} (default: @code{(file-append openntpd "/sbin/ntpd")})
19678 The openntpd executable to use.
19679 @item @code{listen-on} (default: @code{'("127.0.0.1" "::1")})
19680 A list of local IP addresses or hostnames the ntpd daemon should listen on.
19681 @item @code{query-from} (default: @code{'()})
19682 A list of local IP address the ntpd daemon should use for outgoing queries.
19683 @item @code{sensor} (default: @code{'()})
19684 Specify a list of timedelta sensor devices ntpd should use. @code{ntpd}
19685 will listen to each sensor that actually exists and ignore non-existent ones.
19686 See @uref{https://man.openbsd.org/ntpd.conf, upstream documentation} for more
19688 @item @code{server} (default: @code{'()})
19689 Specify a list of IP addresses or hostnames of NTP servers to synchronize to.
19690 @item @code{servers} (default: @code{%openntp-servers})
19691 Specify a list of IP addresses or hostnames of NTP pools to synchronize to.
19692 @item @code{constraint-from} (default: @code{'()})
19693 @code{ntpd} can be configured to query the ‘Date’ from trusted HTTPS servers via TLS.
19694 This time information is not used for precision but acts as an authenticated
19695 constraint, thereby reducing the impact of unauthenticated NTP
19696 man-in-the-middle attacks.
19697 Specify a list of URLs, IP addresses or hostnames of HTTPS servers to provide
19699 @item @code{constraints-from} (default: @code{'()})
19700 As with constraint from, specify a list of URLs, IP addresses or hostnames of
19701 HTTPS servers to provide a constraint. Should the hostname resolve to multiple
19702 IP addresses, @code{ntpd} will calculate a median constraint from all of them.
19707 @deffn {Scheme variable} inetd-service-type
19708 This service runs the @command{inetd} (@pxref{inetd invocation,,,
19709 inetutils, GNU Inetutils}) daemon. @command{inetd} listens for
19710 connections on internet sockets, and lazily starts the specified server
19711 program when a connection is made on one of these sockets.
19713 The value of this service is an @code{inetd-configuration} object. The
19714 following example configures the @command{inetd} daemon to provide the
19715 built-in @command{echo} service, as well as an smtp service which
19716 forwards smtp traffic over ssh to a server @code{smtp-server} behind a
19717 gateway @code{hostname}:
19722 (inetd-configuration
19726 (socket-type 'stream)
19733 (socket-type 'stream)
19737 (program (file-append openssh "/bin/ssh"))
19739 '("ssh" "-qT" "-i" "/path/to/ssh_key"
19740 "-W" "smtp-server:25" "user@@hostname")))))))
19743 See below for more details about @code{inetd-configuration}.
19746 @deftp {Data Type} inetd-configuration
19747 Data type representing the configuration of @command{inetd}.
19750 @item @code{program} (default: @code{(file-append inetutils "/libexec/inetd")})
19751 The @command{inetd} executable to use.
19753 @item @code{entries} (default: @code{'()})
19754 A list of @command{inetd} service entries. Each entry should be created
19755 by the @code{inetd-entry} constructor.
19759 @deftp {Data Type} inetd-entry
19760 Data type representing an entry in the @command{inetd} configuration.
19761 Each entry corresponds to a socket where @command{inetd} will listen for
19765 @item @code{node} (default: @code{#f})
19766 Optional string, a comma-separated list of local addresses
19767 @command{inetd} should use when listening for this service.
19768 @xref{Configuration file,,, inetutils, GNU Inetutils} for a complete
19769 description of all options.
19771 A string, the name must correspond to an entry in @code{/etc/services}.
19772 @item @code{socket-type}
19773 One of @code{'stream}, @code{'dgram}, @code{'raw}, @code{'rdm} or
19775 @item @code{protocol}
19776 A string, must correspond to an entry in @code{/etc/protocols}.
19777 @item @code{wait?} (default: @code{#t})
19778 Whether @command{inetd} should wait for the server to exit before
19779 listening to new service requests.
19781 A string containing the user (and, optionally, group) name of the user
19782 as whom the server should run. The group name can be specified in a
19783 suffix, separated by a colon or period, i.e.@: @code{"user"},
19784 @code{"user:group"} or @code{"user.group"}.
19785 @item @code{program} (default: @code{"internal"})
19786 The server program which will serve the requests, or @code{"internal"}
19787 if @command{inetd} should use a built-in service.
19788 @item @code{arguments} (default: @code{'()})
19789 A list strings or file-like objects, which are the server program's
19790 arguments, starting with the zeroth argument, i.e.@: the name of the
19791 program itself. For @command{inetd}'s internal services, this entry
19792 must be @code{'()} or @code{'("internal")}.
19795 @xref{Configuration file,,, inetutils, GNU Inetutils} for a more
19796 detailed discussion of each configuration field.
19799 @cindex opendht, distributed hash table network service
19800 @cindex dhtproxy, for use with jami
19801 @defvr {Scheme Variable} opendht-service-type
19802 This is the type of the service running a @uref{https://opendht.net,
19803 OpenDHT} node, @command{dhtnode}. The daemon can be used to host your
19804 own proxy service to the distributed hash table (DHT), for example to
19805 connect to with Jami, among other applications.
19807 @quotation Important
19808 When using the OpenDHT proxy server, the IP addresses it ``sees'' from
19809 the clients should be addresses reachable from other peers. In practice
19810 this means that a publicly reachable address is best suited for a proxy
19811 server, outside of your private network. For example, hosting the proxy
19812 server on a IPv4 private local network and exposing it via port
19813 forwarding could work for external peers, but peers local to the proxy
19814 would have their private addresses shared with the external peers,
19815 leading to connectivity problems.
19818 The value of this service is a @code{opendht-configuration} object, as
19822 @c The fields documentation has been auto-generated using the
19823 @c configuration->documentation procedure from
19824 @c (gnu services configuration).
19825 @deftp {Data Type} opendht-configuration
19826 Available @code{opendht-configuration} fields are:
19829 @item @code{opendht} (default: @code{opendht}) (type: file-like)
19830 The @code{opendht} package to use.
19832 @item @code{peer-discovery?} (default: @code{#f}) (type: boolean)
19833 Whether to enable the multicast local peer discovery mechanism.
19835 @item @code{enable-logging?} (default: @code{#f}) (type: boolean)
19836 Whether to enable logging messages to syslog. It is disabled by default
19837 as it is rather verbose.
19839 @item @code{debug?} (default: @code{#f}) (type: boolean)
19840 Whether to enable debug-level logging messages. This has no effect if
19841 logging is disabled.
19843 @item @code{bootstrap-host} (default: @code{"bootstrap.jami.net:4222"}) (type: maybe-string)
19844 The node host name that is used to make the first connection to the
19845 network. A specific port value can be provided by appending the
19846 @code{:PORT} suffix. By default, it uses the Jami bootstrap nodes, but
19847 any host can be specified here. It's also possible to disable
19848 bootstrapping by explicitly setting this field to the
19849 @code{'unset} value.
19851 @item @code{port} (default: @code{4222}) (type: maybe-number)
19852 The UDP port to bind to. When left unspecified, an available port is
19853 automatically selected.
19855 @item @code{proxy-server-port} (type: maybe-number)
19856 Spawn a proxy server listening on the specified port.
19858 @item @code{proxy-server-port-tls} (type: maybe-number)
19859 Spawn a proxy server listening to TLS connections on the specified port.
19865 @defvr {Scheme Variable} tor-service-type
19866 This is the type for a service that runs the @uref{https://torproject.org,
19867 Tor} anonymous networking daemon. The service is configured using a
19868 @code{<tor-configuration>} record. By default, the Tor daemon runs as the
19869 @code{tor} unprivileged user, which is a member of the @code{tor} group.
19873 @deftp {Data Type} tor-configuration
19875 @item @code{tor} (default: @code{tor})
19876 The package that provides the Tor daemon. This package is expected to provide
19877 the daemon at @file{bin/tor} relative to its output directory. The default
19878 package is the @uref{https://www.torproject.org, Tor Project's}
19881 @item @code{config-file} (default: @code{(plain-file "empty" "")})
19882 The configuration file to use. It will be appended to a default configuration
19883 file, and the final configuration file will be passed to @code{tor} via its
19884 @code{-f} option. This may be any ``file-like'' object (@pxref{G-Expressions,
19885 file-like objects}). See @code{man tor} for details on the configuration file
19888 @item @code{hidden-services} (default: @code{'()})
19889 The list of @code{<hidden-service>} records to use. For any hidden service
19890 you include in this list, appropriate configuration to enable the hidden
19891 service will be automatically added to the default configuration file. You
19892 may conveniently create @code{<hidden-service>} records using the
19893 @code{tor-hidden-service} procedure described below.
19895 @item @code{socks-socket-type} (default: @code{'tcp})
19896 The default socket type that Tor should use for its SOCKS socket. This must
19897 be either @code{'tcp} or @code{'unix}. If it is @code{'tcp}, then by default
19898 Tor will listen on TCP port 9050 on the loopback interface (i.e., localhost).
19899 If it is @code{'unix}, then Tor will listen on the UNIX domain socket
19900 @file{/var/run/tor/socks-sock}, which will be made writable by members of the
19903 If you want to customize the SOCKS socket in more detail, leave
19904 @code{socks-socket-type} at its default value of @code{'tcp} and use
19905 @code{config-file} to override the default by providing your own
19906 @code{SocksPort} option.
19908 @item @code{control-socket?} (default: @code{#f})
19909 Whether or not to provide a ``control socket'' by which Tor can be
19910 controlled to, for instance, dynamically instantiate tor onion services.
19911 If @code{#t}, Tor will listen for control commands on the UNIX domain socket
19912 @file{/var/run/tor/control-sock}, which will be made writable by members of the
19918 @cindex hidden service
19919 @deffn {Scheme Procedure} tor-hidden-service @var{name} @var{mapping}
19920 Define a new Tor @dfn{hidden service} called @var{name} and implementing
19921 @var{mapping}. @var{mapping} is a list of port/host tuples, such as:
19924 '((22 "127.0.0.1:22")
19925 (80 "127.0.0.1:8080"))
19928 In this example, port 22 of the hidden service is mapped to local port 22, and
19929 port 80 is mapped to local port 8080.
19931 This creates a @file{/var/lib/tor/hidden-services/@var{name}} directory, where
19932 the @file{hostname} file contains the @code{.onion} host name for the hidden
19935 See @uref{https://www.torproject.org/docs/tor-hidden-service.html.en, the Tor
19936 project's documentation} for more information.
19939 The @code{(gnu services rsync)} module provides the following services:
19941 You might want an rsync daemon if you have files that you want available
19942 so anyone (or just yourself) can download existing files or upload new
19945 @deffn {Scheme Variable} rsync-service-type
19946 This is the service type for the @uref{https://rsync.samba.org, rsync} daemon,
19947 The value for this service type is a
19948 @command{rsync-configuration} record as in this example:
19951 ;; Export two directories over rsync. By default rsync listens on
19952 ;; all the network interfaces.
19953 (service rsync-service-type
19954 (rsync-configuration
19955 (modules (list (rsync-module
19957 (file-name "/srv/zik")
19961 (file-name "/home/charlie/movies"))))))
19964 See below for details about @code{rsync-configuration}.
19967 @deftp {Data Type} rsync-configuration
19968 Data type representing the configuration for @code{rsync-service}.
19971 @item @code{package} (default: @var{rsync})
19972 @code{rsync} package to use.
19974 @item @code{address} (default: @code{#f})
19975 IP address on which @command{rsync} listens for incoming connections.
19976 If unspecified, it defaults to listening on all available addresses.
19978 @item @code{port-number} (default: @code{873})
19979 TCP port on which @command{rsync} listens for incoming connections. If port
19980 is less than @code{1024} @command{rsync} needs to be started as the
19981 @code{root} user and group.
19983 @item @code{pid-file} (default: @code{"/var/run/rsyncd/rsyncd.pid"})
19984 Name of the file where @command{rsync} writes its PID.
19986 @item @code{lock-file} (default: @code{"/var/run/rsyncd/rsyncd.lock"})
19987 Name of the file where @command{rsync} writes its lock file.
19989 @item @code{log-file} (default: @code{"/var/log/rsyncd.log"})
19990 Name of the file where @command{rsync} writes its log file.
19992 @item @code{user} (default: @code{"root"})
19993 Owner of the @code{rsync} process.
19995 @item @code{group} (default: @code{"root"})
19996 Group of the @code{rsync} process.
19998 @item @code{uid} (default: @code{"rsyncd"})
19999 User name or user ID that file transfers to and from that module should take
20000 place as when the daemon was run as @code{root}.
20002 @item @code{gid} (default: @code{"rsyncd"})
20003 Group name or group ID that will be used when accessing the module.
20005 @item @code{modules} (default: @code{%default-modules})
20006 List of ``modules''---i.e., directories exported over rsync. Each
20007 element must be a @code{rsync-module} record, as described below.
20011 @deftp {Data Type} rsync-module
20012 This is the data type for rsync ``modules''. A module is a directory
20013 exported over the rsync protocol. The available fields are as follows:
20017 The module name. This is the name that shows up in URLs. For example,
20018 if the module is called @code{music}, the corresponding URL will be
20019 @code{rsync://host.example.org/music}.
20021 @item @code{file-name}
20022 Name of the directory being exported.
20024 @item @code{comment} (default: @code{""})
20025 Comment associated with the module. Client user interfaces may display
20026 it when they obtain the list of available modules.
20028 @item @code{read-only?} (default: @code{#t})
20029 Whether or not client will be able to upload files. If this is false,
20030 the uploads will be authorized if permissions on the daemon side permit
20033 @item @code{chroot?} (default: @code{#t})
20034 When this is true, the rsync daemon changes root to the module's
20035 directory before starting file transfers with the client. This improves
20036 security, but requires rsync to run as root.
20038 @item @code{timeout} (default: @code{300})
20039 Idle time in seconds after which the daemon closes a connection with the
20044 The @code{(gnu services syncthing)} module provides the following services:
20047 You might want a syncthing daemon if you have files between two or more
20048 computers and want to sync them in real time, safely protected from
20051 @deffn {Scheme Variable} syncthing-service-type
20052 This is the service type for the @uref{https://syncthing.net/,
20053 syncthing} daemon, The value for this service type is a
20054 @command{syncthing-configuration} record as in this example:
20057 (service syncthing-service-type
20058 (syncthing-configuration (user "alice")))
20061 See below for details about @code{syncthing-configuration}.
20063 @deftp {Data Type} syncthing-configuration
20064 Data type representing the configuration for @code{syncthing-service-type}.
20067 @item @code{syncthing} (default: @var{syncthing})
20068 @code{syncthing} package to use.
20070 @item @code{arguments} (default: @var{'()})
20071 List of command-line arguments passing to @code{syncthing} binary.
20073 @item @code{logflags} (default: @var{0})
20074 Sum of logging flags, see
20075 @uref{https://docs.syncthing.net/users/syncthing.html#cmdoption-logflags, Syncthing documentation logflags}.
20077 @item @code{user} (default: @var{#f})
20078 The user as which the Syncthing service is to be run.
20079 This assumes that the specified user exists.
20081 @item @code{group} (default: @var{"users"})
20082 The group as which the Syncthing service is to be run.
20083 This assumes that the specified group exists.
20085 @item @code{home} (default: @var{#f})
20086 Common configuration and data directory. The default configuration
20087 directory is @file{$HOME} of the specified Syncthing @code{user}.
20093 Furthermore, @code{(gnu services ssh)} provides the following services.
20097 @deffn {Scheme Procedure} lsh-service [#:host-key "/etc/lsh/host-key"] @
20098 [#:daemonic? #t] [#:interfaces '()] [#:port-number 22] @
20099 [#:allow-empty-passwords? #f] [#:root-login? #f] @
20100 [#:syslog-output? #t] [#:x11-forwarding? #t] @
20101 [#:tcp/ip-forwarding? #t] [#:password-authentication? #t] @
20102 [#:public-key-authentication? #t] [#:initialize? #t]
20103 Run the @command{lshd} program from @var{lsh} to listen on port @var{port-number}.
20104 @var{host-key} must designate a file containing the host key, and readable
20107 When @var{daemonic?} is true, @command{lshd} will detach from the
20108 controlling terminal and log its output to syslogd, unless one sets
20109 @var{syslog-output?} to false. Obviously, it also makes lsh-service
20110 depend on existence of syslogd service. When @var{pid-file?} is true,
20111 @command{lshd} writes its PID to the file called @var{pid-file}.
20113 When @var{initialize?} is true, automatically create the seed and host key
20114 upon service activation if they do not exist yet. This may take long and
20115 require interaction.
20117 When @var{initialize?} is false, it is up to the user to initialize the
20118 randomness generator (@pxref{lsh-make-seed,,, lsh, LSH Manual}), and to create
20119 a key pair with the private key stored in file @var{host-key} (@pxref{lshd
20120 basics,,, lsh, LSH Manual}).
20122 When @var{interfaces} is empty, lshd listens for connections on all the
20123 network interfaces; otherwise, @var{interfaces} must be a list of host names
20126 @var{allow-empty-passwords?} specifies whether to accept log-ins with empty
20127 passwords, and @var{root-login?} specifies whether to accept log-ins as
20130 The other options should be self-descriptive.
20135 @deffn {Scheme Variable} openssh-service-type
20136 This is the type for the @uref{http://www.openssh.org, OpenSSH} secure
20137 shell daemon, @command{sshd}. Its value must be an
20138 @code{openssh-configuration} record as in this example:
20141 (service openssh-service-type
20142 (openssh-configuration
20143 (x11-forwarding? #t)
20144 (permit-root-login 'prohibit-password)
20146 `(("alice" ,(local-file "alice.pub"))
20147 ("bob" ,(local-file "bob.pub"))))))
20150 See below for details about @code{openssh-configuration}.
20152 This service can be extended with extra authorized keys, as in this
20156 (service-extension openssh-service-type
20157 (const `(("charlie"
20158 ,(local-file "charlie.pub")))))
20162 @deftp {Data Type} openssh-configuration
20163 This is the configuration record for OpenSSH's @command{sshd}.
20166 @item @code{openssh} (default @var{openssh})
20167 The OpenSSH package to use.
20169 @item @code{pid-file} (default: @code{"/var/run/sshd.pid"})
20170 Name of the file where @command{sshd} writes its PID.
20172 @item @code{port-number} (default: @code{22})
20173 TCP port on which @command{sshd} listens for incoming connections.
20175 @item @code{max-connections} (default: @code{200})
20176 Hard limit on the maximum number of simultaneous client connections,
20177 enforced by the inetd-style Shepherd service (@pxref{Service De- and
20178 Constructors, @code{make-inetd-constructor},, shepherd, The GNU Shepherd
20181 @item @code{permit-root-login} (default: @code{#f})
20182 This field determines whether and when to allow logins as root. If
20183 @code{#f}, root logins are disallowed; if @code{#t}, they are allowed.
20184 If it's the symbol @code{'prohibit-password}, then root logins are
20185 permitted but not with password-based authentication.
20187 @item @code{allow-empty-passwords?} (default: @code{#f})
20188 When true, users with empty passwords may log in. When false, they may
20191 @item @code{password-authentication?} (default: @code{#t})
20192 When true, users may log in with their password. When false, they have
20193 other authentication methods.
20195 @item @code{public-key-authentication?} (default: @code{#t})
20196 When true, users may log in using public key authentication. When
20197 false, users have to use other authentication method.
20199 Authorized public keys are stored in @file{~/.ssh/authorized_keys}.
20200 This is used only by protocol version 2.
20202 @item @code{x11-forwarding?} (default: @code{#f})
20203 When true, forwarding of X11 graphical client connections is
20204 enabled---in other words, @command{ssh} options @option{-X} and
20205 @option{-Y} will work.
20207 @item @code{allow-agent-forwarding?} (default: @code{#t})
20208 Whether to allow agent forwarding.
20210 @item @code{allow-tcp-forwarding?} (default: @code{#t})
20211 Whether to allow TCP forwarding.
20213 @item @code{gateway-ports?} (default: @code{#f})
20214 Whether to allow gateway ports.
20216 @item @code{challenge-response-authentication?} (default: @code{#f})
20217 Specifies whether challenge response authentication is allowed (e.g.@: via
20220 @item @code{use-pam?} (default: @code{#t})
20221 Enables the Pluggable Authentication Module interface. If set to
20222 @code{#t}, this will enable PAM authentication using
20223 @code{challenge-response-authentication?} and
20224 @code{password-authentication?}, in addition to PAM account and session
20225 module processing for all authentication types.
20227 Because PAM challenge response authentication usually serves an
20228 equivalent role to password authentication, you should disable either
20229 @code{challenge-response-authentication?} or
20230 @code{password-authentication?}.
20232 @item @code{print-last-log?} (default: @code{#t})
20233 Specifies whether @command{sshd} should print the date and time of the
20234 last user login when a user logs in interactively.
20236 @item @code{subsystems} (default: @code{'(("sftp" "internal-sftp"))})
20237 Configures external subsystems (e.g.@: file transfer daemon).
20239 This is a list of two-element lists, each of which containing the
20240 subsystem name and a command (with optional arguments) to execute upon
20243 The command @command{internal-sftp} implements an in-process SFTP
20244 server. Alternatively, one can specify the @command{sftp-server} command:
20246 (service openssh-service-type
20247 (openssh-configuration
20249 `(("sftp" ,(file-append openssh "/libexec/sftp-server"))))))
20252 @item @code{accepted-environment} (default: @code{'()})
20253 List of strings describing which environment variables may be exported.
20255 Each string gets on its own line. See the @code{AcceptEnv} option in
20256 @code{man sshd_config}.
20258 This example allows ssh-clients to export the @env{COLORTERM} variable.
20259 It is set by terminal emulators, which support colors. You can use it in
20260 your shell's resource file to enable colors for the prompt and commands
20261 if this variable is set.
20264 (service openssh-service-type
20265 (openssh-configuration
20266 (accepted-environment '("COLORTERM"))))
20269 @item @code{authorized-keys} (default: @code{'()})
20270 @cindex authorized keys, SSH
20271 @cindex SSH authorized keys
20272 This is the list of authorized keys. Each element of the list is a user
20273 name followed by one or more file-like objects that represent SSH public
20277 (openssh-configuration
20279 `(("rekado" ,(local-file "rekado.pub"))
20280 ("chris" ,(local-file "chris.pub"))
20281 ("root" ,(local-file "rekado.pub") ,(local-file "chris.pub")))))
20285 registers the specified public keys for user accounts @code{rekado},
20286 @code{chris}, and @code{root}.
20288 Additional authorized keys can be specified @i{via}
20289 @code{service-extension}.
20291 Note that this does @emph{not} interfere with the use of
20292 @file{~/.ssh/authorized_keys}.
20294 @item @code{generate-host-keys?} (default: @code{#t})
20295 Whether to generate host key pairs with @command{ssh-keygen -A} under
20296 @file{/etc/ssh} if there are none.
20298 Generating key pairs takes a few seconds when enough entropy is
20299 available and is only done once. You might want to turn it off for
20300 instance in a virtual machine that does not need it because host keys
20301 are provided in some other way, and where the extra boot time is a
20304 @item @code{log-level} (default: @code{'info})
20305 This is a symbol specifying the logging level: @code{quiet}, @code{fatal},
20306 @code{error}, @code{info}, @code{verbose}, @code{debug}, etc. See the man
20307 page for @file{sshd_config} for the full list of level names.
20309 @item @code{extra-content} (default: @code{""})
20310 This field can be used to append arbitrary text to the configuration file. It
20311 is especially useful for elaborate configurations that cannot be expressed
20312 otherwise. This configuration, for example, would generally disable root
20313 logins, but permit them from one specific IP address:
20316 (openssh-configuration
20318 Match Address 192.168.0.1
20319 PermitRootLogin yes"))
20325 @deffn {Scheme Procedure} dropbear-service [@var{config}]
20326 Run the @uref{https://matt.ucc.asn.au/dropbear/dropbear.html,Dropbear SSH
20327 daemon} with the given @var{config}, a @code{<dropbear-configuration>}
20330 For example, to specify a Dropbear service listening on port 1234, add
20331 this call to the operating system's @code{services} field:
20334 (dropbear-service (dropbear-configuration
20335 (port-number 1234)))
20339 @deftp {Data Type} dropbear-configuration
20340 This data type represents the configuration of a Dropbear SSH daemon.
20343 @item @code{dropbear} (default: @var{dropbear})
20344 The Dropbear package to use.
20346 @item @code{port-number} (default: 22)
20347 The TCP port where the daemon waits for incoming connections.
20349 @item @code{syslog-output?} (default: @code{#t})
20350 Whether to enable syslog output.
20352 @item @code{pid-file} (default: @code{"/var/run/dropbear.pid"})
20353 File name of the daemon's PID file.
20355 @item @code{root-login?} (default: @code{#f})
20356 Whether to allow @code{root} logins.
20358 @item @code{allow-empty-passwords?} (default: @code{#f})
20359 Whether to allow empty passwords.
20361 @item @code{password-authentication?} (default: @code{#t})
20362 Whether to enable password-based authentication.
20367 @deffn {Scheme Variable} autossh-service-type
20368 This is the type for the @uref{https://www.harding.motd.ca/autossh,
20369 AutoSSH} program that runs a copy of @command{ssh} and monitors it,
20370 restarting it as necessary should it die or stop passing traffic.
20371 AutoSSH can be run manually from the command-line by passing arguments
20372 to the binary @command{autossh} from the package @code{autossh}, but it
20373 can also be run as a Guix service. This latter use case is documented
20376 AutoSSH can be used to forward local traffic to a remote machine using
20377 an SSH tunnel, and it respects the @file{~/.ssh/config} of the user it
20380 For example, to specify a service running autossh as the user
20381 @code{pino} and forwarding all local connections to port @code{8081} to
20382 @code{remote:8081} using an SSH tunnel, add this call to the operating
20383 system's @code{services} field:
20386 (service autossh-service-type
20387 (autossh-configuration
20389 (ssh-options (list "-T" "-N" "-L" "8081:localhost:8081" "remote.net"))))
20393 @deftp {Data Type} autossh-configuration
20394 This data type represents the configuration of an AutoSSH service.
20398 @item @code{user} (default @code{"autossh"})
20399 The user as which the AutoSSH service is to be run.
20400 This assumes that the specified user exists.
20402 @item @code{poll} (default @code{600})
20403 Specifies the connection poll time in seconds.
20405 @item @code{first-poll} (default @code{#f})
20406 Specifies how many seconds AutoSSH waits before the first connection
20407 test. After this first test, polling is resumed at the pace defined in
20408 @code{poll}. When set to @code{#f}, the first poll is not treated
20409 specially and will also use the connection poll specified in
20412 @item @code{gate-time} (default @code{30})
20413 Specifies how many seconds an SSH connection must be active before it is
20414 considered successful.
20416 @item @code{log-level} (default @code{1})
20417 The log level, corresponding to the levels used by syslog---so @code{0}
20418 is the most silent while @code{7} is the chattiest.
20420 @item @code{max-start} (default @code{#f})
20421 The maximum number of times SSH may be (re)started before AutoSSH exits.
20422 When set to @code{#f}, no maximum is configured and AutoSSH may restart indefinitely.
20424 @item @code{message} (default @code{""})
20425 The message to append to the echo message sent when testing connections.
20427 @item @code{port} (default @code{"0"})
20428 The ports used for monitoring the connection. When set to @code{"0"},
20429 monitoring is disabled. When set to @code{"@var{n}"} where @var{n} is
20430 a positive integer, ports @var{n} and @var{n}+1 are used for
20431 monitoring the connection, such that port @var{n} is the base
20432 monitoring port and @code{n+1} is the echo port. When set to
20433 @code{"@var{n}:@var{m}"} where @var{n} and @var{m} are positive
20434 integers, the ports @var{n} and @var{m} are used for monitoring the
20435 connection, such that port @var{n} is the base monitoring port and
20436 @var{m} is the echo port.
20438 @item @code{ssh-options} (default @code{'()})
20439 The list of command-line arguments to pass to @command{ssh} when it is
20440 run. Options @option{-f} and @option{-M} are reserved for AutoSSH and
20441 may cause undefined behaviour.
20447 @deffn {Scheme Variable} webssh-service-type
20448 This is the type for the @uref{https://webssh.huashengdun.org/, WebSSH}
20449 program that runs a web SSH client. WebSSH can be run manually from the
20450 command-line by passing arguments to the binary @command{wssh} from the
20451 package @code{webssh}, but it can also be run as a Guix service. This
20452 latter use case is documented here.
20454 For example, to specify a service running WebSSH on loopback interface
20455 on port @code{8888} with reject policy with a list of allowed to
20456 connection hosts, and NGINX as a reverse-proxy to this service listening
20457 for HTTPS connection, add this call to the operating system's
20458 @code{services} field:
20461 (service webssh-service-type
20462 (webssh-configuration (address "127.0.0.1")
20465 (known-hosts '("localhost ecdsa-sha2-nistp256 AAAA…"
20466 "127.0.0.1 ecdsa-sha2-nistp256 AAAA…"))))
20468 (service nginx-service-type
20469 (nginx-configuration
20472 (nginx-server-configuration
20473 (inherit %webssh-configuration-nginx)
20474 (server-name '("webssh.example.com"))
20475 (listen '("443 ssl"))
20476 (ssl-certificate (letsencrypt-certificate "webssh.example.com"))
20477 (ssl-certificate-key (letsencrypt-key "webssh.example.com"))
20479 (cons (nginx-location-configuration
20480 (uri "/.well-known")
20481 (body '("root /var/www;")))
20482 (nginx-server-configuration-locations %webssh-configuration-nginx))))))))
20486 @deftp {Data Type} webssh-configuration
20487 Data type representing the configuration for @code{webssh-service}.
20490 @item @code{package} (default: @var{webssh})
20491 @code{webssh} package to use.
20493 @item @code{user-name} (default: @var{"webssh"})
20494 User name or user ID that file transfers to and from that module should take
20497 @item @code{group-name} (default: @var{"webssh"})
20498 Group name or group ID that will be used when accessing the module.
20500 @item @code{address} (default: @var{#f})
20501 IP address on which @command{webssh} listens for incoming connections.
20503 @item @code{port} (default: @var{8888})
20504 TCP port on which @command{webssh} listens for incoming connections.
20506 @item @code{policy} (default: @var{#f})
20507 Connection policy. @var{reject} policy requires to specify @var{known-hosts}.
20509 @item @code{known-hosts} (default: @var{'()})
20510 List of hosts which allowed for SSH connection from @command{webssh}.
20512 @item @code{log-file} (default: @file{"/var/log/webssh.log"})
20513 Name of the file where @command{webssh} writes its log file.
20515 @item @code{log-level} (default: @var{#f})
20521 @defvr {Scheme Variable} %facebook-host-aliases
20522 This variable contains a string for use in @file{/etc/hosts}
20523 (@pxref{Host Names,,, libc, The GNU C Library Reference Manual}). Each
20524 line contains a entry that maps a known server name of the Facebook
20525 on-line service---e.g., @code{www.facebook.com}---to the local
20526 host---@code{127.0.0.1} or its IPv6 equivalent, @code{::1}.
20528 This variable is typically used in the @code{hosts-file} field of an
20529 @code{operating-system} declaration (@pxref{operating-system Reference,
20530 @file{/etc/hosts}}):
20533 (use-modules (gnu) (guix))
20536 (host-name "mymachine")
20539 ;; Create a /etc/hosts file with aliases for "localhost"
20540 ;; and "mymachine", as well as for Facebook servers.
20541 (plain-file "hosts"
20542 (string-append (local-host-aliases host-name)
20543 %facebook-host-aliases))))
20546 This mechanism can prevent programs running locally, such as Web
20547 browsers, from accessing Facebook.
20550 The @code{(gnu services avahi)} provides the following definition.
20552 @defvr {Scheme Variable} avahi-service-type
20553 This is the service that runs @command{avahi-daemon}, a system-wide
20554 mDNS/DNS-SD responder that allows for service discovery and
20555 ``zero-configuration'' host name lookups (see @uref{https://avahi.org/}).
20556 Its value must be an @code{avahi-configuration} record---see below.
20558 This service extends the name service cache daemon (nscd) so that it can
20559 resolve @code{.local} host names using
20560 @uref{https://0pointer.de/lennart/projects/nss-mdns/, nss-mdns}. @xref{Name
20561 Service Switch}, for information on host name resolution.
20563 Additionally, add the @var{avahi} package to the system profile so that
20564 commands such as @command{avahi-browse} are directly usable.
20567 @deftp {Data Type} avahi-configuration
20568 Data type representation the configuration for Avahi.
20572 @item @code{host-name} (default: @code{#f})
20573 If different from @code{#f}, use that as the host name to
20574 publish for this machine; otherwise, use the machine's actual host name.
20576 @item @code{publish?} (default: @code{#t})
20577 When true, allow host names and services to be published (broadcast) over the
20580 @item @code{publish-workstation?} (default: @code{#t})
20581 When true, @command{avahi-daemon} publishes the machine's host name and IP
20582 address via mDNS on the local network. To view the host names published on
20583 your local network, you can run:
20586 avahi-browse _workstation._tcp
20589 @item @code{wide-area?} (default: @code{#f})
20590 When true, DNS-SD over unicast DNS is enabled.
20592 @item @code{ipv4?} (default: @code{#t})
20593 @itemx @code{ipv6?} (default: @code{#t})
20594 These fields determine whether to use IPv4/IPv6 sockets.
20596 @item @code{domains-to-browse} (default: @code{'()})
20597 This is a list of domains to browse.
20601 @deffn {Scheme Variable} openvswitch-service-type
20602 This is the type of the @uref{https://www.openvswitch.org, Open vSwitch}
20603 service, whose value should be an @code{openvswitch-configuration}
20607 @deftp {Data Type} openvswitch-configuration
20608 Data type representing the configuration of Open vSwitch, a multilayer
20609 virtual switch which is designed to enable massive network automation
20610 through programmatic extension.
20613 @item @code{package} (default: @var{openvswitch})
20614 Package object of the Open vSwitch.
20619 @defvr {Scheme Variable} pagekite-service-type
20620 This is the service type for the @uref{https://pagekite.net, PageKite} service,
20621 a tunneling solution for making localhost servers publicly visible, even from
20622 behind restrictive firewalls or NAT without forwarded ports. The value for
20623 this service type is a @code{pagekite-configuration} record.
20625 Here's an example exposing the local HTTP and SSH daemons:
20628 (service pagekite-service-type
20629 (pagekite-configuration
20630 (kites '("http:@@kitename:localhost:80:@@kitesecret"
20631 "raw/22:@@kitename:localhost:22:@@kitesecret"))
20632 (extra-file "/etc/pagekite.rc")))
20636 @deftp {Data Type} pagekite-configuration
20637 Data type representing the configuration of PageKite.
20640 @item @code{package} (default: @var{pagekite})
20641 Package object of PageKite.
20643 @item @code{kitename} (default: @code{#f})
20644 PageKite name for authenticating to the frontend server.
20646 @item @code{kitesecret} (default: @code{#f})
20647 Shared secret for authenticating to the frontend server. You should probably
20648 put this inside @code{extra-file} instead.
20650 @item @code{frontend} (default: @code{#f})
20651 Connect to the named PageKite frontend server instead of the
20652 @uref{https://pagekite.net,,pagekite.net} service.
20654 @item @code{kites} (default: @code{'("http:@@kitename:localhost:80:@@kitesecret")})
20655 List of service kites to use. Exposes HTTP on port 80 by default. The format
20656 is @code{proto:kitename:host:port:secret}.
20658 @item @code{extra-file} (default: @code{#f})
20659 Extra configuration file to read, which you are expected to create manually.
20660 Use this to add additional options and manage shared secrets out-of-band.
20665 @defvr {Scheme Variable} yggdrasil-service-type
20666 The service type for connecting to the @uref{https://yggdrasil-network.github.io/,
20667 Yggdrasil network}, an early-stage implementation of a fully end-to-end
20668 encrypted IPv6 network.
20671 Yggdrasil provides name-independent routing with cryptographically generated
20672 addresses. Static addressing means you can keep the same address as long as
20673 you want, even if you move to a new location, or generate a new address (by
20674 generating new keys) whenever you want.
20675 @uref{https://yggdrasil-network.github.io/2018/07/28/addressing.html}
20678 Pass it a value of @code{yggdrasil-configuration} to connect it to public
20679 peers and/or local peers.
20681 Here is an example using public peers and a static address. The static
20682 signing and encryption keys are defined in @file{/etc/yggdrasil-private.conf}
20683 (the default value for @code{config-file}).
20686 ;; part of the operating-system declaration
20687 (service yggdrasil-service-type
20688 (yggdrasil-configuration
20689 (autoconf? #f) ;; use only the public peers
20692 ;; https://github.com/yggdrasil-network/public-peers
20693 '((peers . #("tcp://1.2.3.4:1337"))))
20694 ;; /etc/yggdrasil-private.conf is the default value for config-file
20698 # sample content for /etc/yggdrasil-private.conf
20700 # Your public key. Your peers may ask you for this to put
20701 # into their AllowedPublicKeys configuration.
20702 PublicKey: 64277...
20704 # Your private key. DO NOT share this with anyone!
20705 PrivateKey: 5c750...
20710 @deftp {Data Type} yggdrasil-configuration
20711 Data type representing the configuration of Yggdrasil.
20714 @item @code{package} (default: @code{yggdrasil})
20715 Package object of Yggdrasil.
20717 @item @code{json-config} (default: @code{'()})
20718 Contents of @file{/etc/yggdrasil.conf}. Will be merged with
20719 @file{/etc/yggdrasil-private.conf}. Note that these settings are stored in
20720 the Guix store, which is readable to all users. @strong{Do not store your
20721 private keys in it}. See the output of @code{yggdrasil -genconf} for a
20722 quick overview of valid keys and their default values.
20724 @item @code{autoconf?} (default: @code{#f})
20725 Whether to use automatic mode. Enabling it makes Yggdrasil use adynamic IP
20726 and peer with IPv6 neighbors.
20728 @item @code{log-level} (default: @code{'info})
20729 How much detail to include in logs. Use @code{'debug} for more detail.
20731 @item @code{log-to} (default: @code{'stdout})
20732 Where to send logs. By default, the service logs standard output to
20733 @file{/var/log/yggdrasil.log}. The alternative is @code{'syslog}, which
20734 sends output to the running syslog service.
20736 @item @code{config-file} (default: @code{"/etc/yggdrasil-private.conf"})
20737 What HJSON file to load sensitive data from. This is where private keys
20738 should be stored, which are necessary to specify if you don't want a
20739 randomized address after each restart. Use @code{#f} to disable. Options
20740 defined in this file take precedence over @code{json-config}. Use the output
20741 of @code{yggdrasil -genconf} as a starting point. To configure a static
20742 address, delete everything except these options:
20745 @item @code{EncryptionPublicKey}
20746 @item @code{EncryptionPrivateKey}
20747 @item @code{SigningPublicKey}
20748 @item @code{SigningPrivateKey}
20754 @defvr {Scheme Variable} ipfs-service-type
20755 The service type for connecting to the @uref{https://ipfs.io,IPFS network},
20756 a global, versioned, peer-to-peer file system. Pass it a
20757 @code{ipfs-configuration} to change the ports used for the gateway and API.
20759 Here's an example configuration, using some non-standard ports:
20762 (service ipfs-service-type
20763 (ipfs-configuration
20764 (gateway "/ip4/127.0.0.1/tcp/8880")
20765 (api "/ip4/127.0.0.1/tcp/8881")))
20769 @deftp {Data Type} ipfs-configuration
20770 Data type representing the configuration of IPFS.
20773 @item @code{package} (default: @code{go-ipfs})
20774 Package object of IPFS.
20776 @item @code{gateway} (default: @code{"/ip4/127.0.0.1/tcp/8082"})
20777 Address of the gateway, in ‘multiaddress’ format.
20779 @item @code{api} (default: @code{"/ip4/127.0.0.1/tcp/5001"})
20780 Address of the API endpoint, in ‘multiaddress’ format.
20785 @deffn {Scheme Variable} keepalived-service-type
20786 This is the type for the @uref{https://www.keepalived.org/, Keepalived}
20787 routing software, @command{keepalived}. Its value must be an
20788 @code{keepalived-configuration} record as in this example for master
20792 (service keepalived-service-type
20793 (keepalived-configuration
20794 (config-file (local-file "keepalived-master.conf"))))
20797 where @file{keepalived-master.conf}:
20800 vrrp_instance my-group @{
20803 virtual_router_id 100
20805 unicast_peer @{ 10.0.0.2 @}
20806 virtual_ipaddress @{
20812 and for backup machine:
20815 (service keepalived-service-type
20816 (keepalived-configuration
20817 (config-file (local-file "keepalived-backup.conf"))))
20820 where @file{keepalived-backup.conf}:
20823 vrrp_instance my-group @{
20826 virtual_router_id 100
20828 unicast_peer @{ 10.0.0.3 @}
20829 virtual_ipaddress @{
20836 @node Unattended Upgrades
20837 @subsection Unattended Upgrades
20839 @cindex unattended upgrades
20840 @cindex upgrades, unattended
20841 Guix provides a service to perform @emph{unattended upgrades}:
20842 periodically, the system automatically reconfigures itself from the
20843 latest Guix. Guix System has several properties that make unattended
20848 upgrades are transactional (either the upgrade succeeds or it fails, but
20849 you cannot end up with an ``in-between'' system state);
20851 the upgrade log is kept---you can view it with @command{guix system
20852 list-generations}---and you can roll back to any previous generation,
20853 should the upgraded system fail to behave as intended;
20855 channel code is authenticated so you know you can only run genuine code
20856 (@pxref{Channels});
20858 @command{guix system reconfigure} prevents downgrades, which makes it
20859 immune to @dfn{downgrade attacks}.
20862 To set up unattended upgrades, add an instance of
20863 @code{unattended-upgrade-service-type} like the one below to the list of
20864 your operating system services:
20867 (service unattended-upgrade-service-type)
20870 The defaults above set up weekly upgrades: every Sunday at midnight.
20871 You do not need to provide the operating system configuration file: it
20872 uses @file{/run/current-system/configuration.scm}, which ensures it
20873 always uses your latest configuration---@pxref{provenance-service-type},
20874 for more information about this file.
20876 There are several things that can be configured, in particular the
20877 periodicity and services (daemons) to be restarted upon completion.
20878 When the upgrade is successful, the service takes care of deleting
20879 system generations older that some threshold, as per @command{guix
20880 system delete-generations}. See the reference below for details.
20882 To ensure that upgrades are actually happening, you can run
20883 @command{guix system describe}. To investigate upgrade failures, visit
20884 the unattended upgrade log file (see below).
20886 @defvr {Scheme Variable} unattended-upgrade-service-type
20887 This is the service type for unattended upgrades. It sets up an mcron
20888 job (@pxref{Scheduled Job Execution}) that runs @command{guix system
20889 reconfigure} from the latest version of the specified channels.
20891 Its value must be a @code{unattended-upgrade-configuration} record (see
20895 @deftp {Data Type} unattended-upgrade-configuration
20896 This data type represents the configuration of the unattended upgrade
20897 service. The following fields are available:
20900 @item @code{schedule} (default: @code{"30 01 * * 0"})
20901 This is the schedule of upgrades, expressed as a gexp containing an
20902 mcron job schedule (@pxref{Guile Syntax, mcron job specifications,,
20903 mcron, GNU@tie{}mcron}).
20905 @item @code{channels} (default: @code{#~%default-channels})
20906 This gexp specifies the channels to use for the upgrade
20907 (@pxref{Channels}). By default, the tip of the official @code{guix}
20910 @item @code{operating-system-file} (default: @code{"/run/current-system/configuration.scm"})
20911 This field specifies the operating system configuration file to use.
20912 The default is to reuse the config file of the current configuration.
20914 There are cases, though, where referring to
20915 @file{/run/current-system/configuration.scm} is not enough, for instance
20916 because that file refers to extra files (SSH public keys, extra
20917 configuration files, etc.) @i{via} @code{local-file} and similar
20918 constructs. For those cases, we recommend something along these lines:
20921 (unattended-upgrade-configuration
20922 (operating-system-file
20923 (file-append (local-file "." "config-dir" #:recursive? #t)
20927 The effect here is to import all of the current directory into the
20928 store, and to refer to @file{config.scm} within that directory.
20929 Therefore, uses of @code{local-file} within @file{config.scm} will work
20930 as expected. @xref{G-Expressions}, for information about
20931 @code{local-file} and @code{file-append}.
20933 @item @code{services-to-restart} (default: @code{'(mcron)})
20934 This field specifies the Shepherd services to restart when the upgrade
20937 Those services are restarted right away upon completion, as with
20938 @command{herd restart}, which ensures that the latest version is
20939 running---remember that by default @command{guix system reconfigure}
20940 only restarts services that are not currently running, which is
20941 conservative: it minimizes disruption but leaves outdated services
20944 Use @command{herd status} to find out candidates for restarting.
20945 @xref{Services}, for general information about services. Common
20946 services to restart would include @code{ntpd} and @code{ssh-daemon}.
20948 By default, the @code{mcron} service is restarted. This ensures that
20949 the latest version of the unattended upgrade job will be used next time.
20951 @item @code{system-expiration} (default: @code{(* 3 30 24 3600)})
20952 This is the expiration time in seconds for system generations. System
20953 generations older that this amount of time are deleted with
20954 @command{guix system delete-generations} when an upgrade completes.
20957 The unattended upgrade service does not run the garbage collector. You
20958 will probably want to set up your own mcron job to run @command{guix gc}
20962 @item @code{maximum-duration} (default: @code{3600})
20963 Maximum duration in seconds for the upgrade; past that time, the upgrade
20966 This is primarily useful to ensure the upgrade does not end up
20967 rebuilding or re-downloading ``the world''.
20969 @item @code{log-file} (default: @code{"/var/log/unattended-upgrade.log"})
20970 File where unattended upgrades are logged.
20975 @subsection X Window
20978 @cindex X Window System
20979 @cindex login manager
20980 Support for the X Window graphical display system---specifically
20981 Xorg---is provided by the @code{(gnu services xorg)} module. Note that
20982 there is no @code{xorg-service} procedure. Instead, the X server is
20983 started by the @dfn{login manager}, by default the GNOME Display Manager (GDM).
20986 @cindex GNOME, login manager
20987 GDM of course allows users to log in into window managers and desktop
20988 environments other than GNOME; for those using GNOME, GDM is required for
20989 features such as automatic screen locking.
20991 @cindex window manager
20992 To use X11, you must install at least one @dfn{window manager}---for
20993 example the @code{windowmaker} or @code{openbox} packages---preferably
20994 by adding it to the @code{packages} field of your operating system
20995 definition (@pxref{operating-system Reference, system-wide packages}).
20997 @anchor{wayland-gdm}
20998 GDM also supports Wayland: it can itself use Wayland instead of X11 for
20999 its user interface, and it can also start Wayland sessions. The former is
21000 required for the latter, to enable, set @code{wayland?} to @code{#t} in
21001 @code{gdm-configuration}.
21003 @defvr {Scheme Variable} gdm-service-type
21004 This is the type for the @uref{https://wiki.gnome.org/Projects/GDM/, GNOME
21005 Desktop Manager} (GDM), a program that manages graphical display servers and
21006 handles graphical user logins. Its value must be a @code{gdm-configuration}
21009 @cindex session types
21010 GDM looks for @dfn{session types} described by the @file{.desktop} files in
21011 @file{/run/current-system/profile/share/xsessions} (for X11 sessions) and
21012 @file{/run/current-system/profile/share/wayland-sessions} (for Wayland
21013 sessions) and allows users to choose a session from the log-in screen.
21014 Packages such as @code{gnome}, @code{xfce}, @code{i3} and @code{sway} provide
21015 @file{.desktop} files; adding them to the system-wide set of packages
21016 automatically makes them available at the log-in screen.
21018 In addition, @file{~/.xsession} files are honored. When available,
21019 @file{~/.xsession} must be an executable that starts a window manager
21020 and/or other X clients.
21023 @deftp {Data Type} gdm-configuration
21025 @item @code{auto-login?} (default: @code{#f})
21026 @itemx @code{default-user} (default: @code{#f})
21027 When @code{auto-login?} is false, GDM presents a log-in screen.
21029 When @code{auto-login?} is true, GDM logs in directly as
21030 @code{default-user}.
21032 @item @code{debug?} (default: @code{#f})
21033 When true, GDM writes debug messages to its log.
21035 @item @code{gnome-shell-assets} (default: ...)
21036 List of GNOME Shell assets needed by GDM: icon theme, fonts, etc.
21038 @item @code{xorg-configuration} (default: @code{(xorg-configuration)})
21039 Configuration of the Xorg graphical server.
21041 @item @code{x-session} (default: @code{(xinitrc)})
21042 Script to run before starting a X session.
21044 @item @code{dbus-daemon} (default: @code{dbus-daemon-wrapper})
21045 File name of the @code{dbus-daemon} executable.
21047 @item @code{gdm} (default: @code{gdm})
21048 The GDM package to use.
21050 @item @code{wayland?} (default: @code{#f})
21051 When true, enables Wayland in GDM, necessary to use Wayland sessions.
21053 @item @code{wayland-session} (default: @code{gdm-wayland-session-wrapper})
21054 The Wayland session wrapper to use, needed to setup the
21059 @defvr {Scheme Variable} slim-service-type
21060 This is the type for the SLiM graphical login manager for X11.
21062 Like GDM, SLiM looks for session types described by @file{.desktop} files and
21063 allows users to choose a session from the log-in screen using @kbd{F1}. It
21064 also honors @file{~/.xsession} files.
21066 Unlike GDM, SLiM does not spawn the user session on a different VT after
21067 logging in, which means that you can only start one graphical session. If you
21068 want to be able to run multiple graphical sessions at the same time you have
21069 to add multiple SLiM services to your system services. The following example
21070 shows how to replace the default GDM service with two SLiM services on tty7
21074 (use-modules (gnu services)
21075 (gnu services desktop)
21076 (gnu services xorg))
21080 (services (cons* (service slim-service-type (slim-configuration
21083 (service slim-service-type (slim-configuration
21086 (modify-services %desktop-services
21087 (delete gdm-service-type)))))
21092 @deftp {Data Type} slim-configuration
21093 Data type representing the configuration of @code{slim-service-type}.
21096 @item @code{allow-empty-passwords?} (default: @code{#t})
21097 Whether to allow logins with empty passwords.
21099 @item @code{gnupg?} (default: @code{#f})
21100 If enabled, @code{pam-gnupg} will attempt to automatically unlock the
21101 user's GPG keys with the login password via @code{gpg-agent}. The
21102 keygrips of all keys to be unlocked should be written to
21103 @file{~/.pam-gnupg}, and can be queried with @code{gpg -K
21104 --with-keygrip}. Presetting passphrases must be enabled by adding
21105 @code{allow-preset-passphrase} in @file{~/.gnupg/gpg-agent.conf}.
21107 @item @code{auto-login?} (default: @code{#f})
21108 @itemx @code{default-user} (default: @code{""})
21109 When @code{auto-login?} is false, SLiM presents a log-in screen.
21111 When @code{auto-login?} is true, SLiM logs in directly as
21112 @code{default-user}.
21114 @item @code{theme} (default: @code{%default-slim-theme})
21115 @itemx @code{theme-name} (default: @code{%default-slim-theme-name})
21116 The graphical theme to use and its name.
21118 @item @code{auto-login-session} (default: @code{#f})
21119 If true, this must be the name of the executable to start as the default
21120 session---e.g., @code{(file-append windowmaker "/bin/windowmaker")}.
21122 If false, a session described by one of the available @file{.desktop}
21123 files in @code{/run/current-system/profile} and @code{~/.guix-profile}
21127 You must install at least one window manager in the system profile or in
21128 your user profile. Failing to do that, if @code{auto-login-session} is
21129 false, you will be unable to log in.
21132 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
21133 Configuration of the Xorg graphical server.
21135 @item @code{display} (default @code{":0"})
21136 The display on which to start the Xorg graphical server.
21138 @item @code{vt} (default @code{"vt7"})
21139 The VT on which to start the Xorg graphical server.
21141 @item @code{xauth} (default: @code{xauth})
21142 The XAuth package to use.
21144 @item @code{shepherd} (default: @code{shepherd})
21145 The Shepherd package used when invoking @command{halt} and
21148 @item @code{sessreg} (default: @code{sessreg})
21149 The sessreg package used in order to register the session.
21151 @item @code{slim} (default: @code{slim})
21152 The SLiM package to use.
21156 @defvr {Scheme Variable} %default-theme
21157 @defvrx {Scheme Variable} %default-theme-name
21158 The default SLiM theme and its name.
21162 @cindex login manager
21164 @defvr {Scheme Variable} sddm-service-type
21165 This is the type of the service to run the
21166 @uref{https://github.com/sddm/sddm,SDDM display manager}. Its value
21167 must be a @code{sddm-configuration} record (see below).
21169 Here's an example use:
21172 (service sddm-service-type
21173 (sddm-configuration
21174 (auto-login-user "alice")
21175 (auto-login-session "xfce.desktop")))
21179 @deftp {Data Type} sddm-configuration
21180 This data type represents the configuration of the SDDM login manager.
21181 The available fields are:
21184 @item @code{sddm} (default: @code{sddm})
21185 The SDDM package to use.
21187 @item @code{display-server} (default: "x11")
21188 Select display server to use for the greeter. Valid values are
21189 @samp{"x11"} or @samp{"wayland"}.
21191 @item @code{numlock} (default: "on")
21192 Valid values are @samp{"on"}, @samp{"off"} or @samp{"none"}.
21194 @item @code{halt-command} (default @code{#~(string-append #$shepherd "/sbin/halt")})
21195 Command to run when halting.
21197 @item @code{reboot-command} (default @code{#~(string-append #$shepherd "/sbin/reboot")})
21198 Command to run when rebooting.
21200 @item @code{theme} (default "maldives")
21201 Theme to use. Default themes provided by SDDM are @samp{"elarun"},
21202 @samp{"maldives"} or @samp{"maya"}.
21204 @item @code{themes-directory} (default "/run/current-system/profile/share/sddm/themes")
21205 Directory to look for themes.
21207 @item @code{faces-directory} (default "/run/current-system/profile/share/sddm/faces")
21208 Directory to look for faces.
21210 @item @code{default-path} (default "/run/current-system/profile/bin")
21211 Default PATH to use.
21213 @item @code{minimum-uid} (default: 1000)
21214 Minimum UID displayed in SDDM and allowed for log-in.
21216 @item @code{maximum-uid} (default: 2000)
21217 Maximum UID to display in SDDM.
21219 @item @code{remember-last-user?} (default #t)
21220 Remember last user.
21222 @item @code{remember-last-session?} (default #t)
21223 Remember last session.
21225 @item @code{hide-users} (default "")
21226 Usernames to hide from SDDM greeter.
21228 @item @code{hide-shells} (default @code{#~(string-append #$shadow "/sbin/nologin")})
21229 Users with shells listed will be hidden from the SDDM greeter.
21231 @item @code{session-command} (default @code{#~(string-append #$sddm "/share/sddm/scripts/wayland-session")})
21232 Script to run before starting a wayland session.
21234 @item @code{sessions-directory} (default "/run/current-system/profile/share/wayland-sessions")
21235 Directory to look for desktop files starting wayland sessions.
21237 @item @code{xorg-configuration} (default @code{(xorg-configuration)})
21238 Configuration of the Xorg graphical server.
21240 @item @code{xauth-path} (default @code{#~(string-append #$xauth "/bin/xauth")})
21243 @item @code{xephyr-path} (default @code{#~(string-append #$xorg-server "/bin/Xephyr")})
21246 @item @code{xdisplay-start} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xsetup")})
21247 Script to run after starting xorg-server.
21249 @item @code{xdisplay-stop} (default @code{#~(string-append #$sddm "/share/sddm/scripts/Xstop")})
21250 Script to run before stopping xorg-server.
21252 @item @code{xsession-command} (default: @code{xinitrc})
21253 Script to run before starting a X session.
21255 @item @code{xsessions-directory} (default: "/run/current-system/profile/share/xsessions")
21256 Directory to look for desktop files starting X sessions.
21258 @item @code{minimum-vt} (default: 7)
21261 @item @code{auto-login-user} (default "")
21262 User account that will be automatically logged in.
21263 Setting this to the empty string disables auto-login.
21265 @item @code{auto-login-session} (default "")
21266 The @file{.desktop} file name to use as the auto-login session, or the empty string.
21268 @item @code{relogin?} (default #f)
21269 Relogin after logout.
21275 @cindex Xorg, configuration
21276 @deftp {Data Type} xorg-configuration
21277 This data type represents the configuration of the Xorg graphical display
21278 server. Note that there is no Xorg service; instead, the X server is started
21279 by a ``display manager'' such as GDM, SDDM, and SLiM@. Thus, the configuration
21280 of these display managers aggregates an @code{xorg-configuration} record.
21283 @item @code{modules} (default: @code{%default-xorg-modules})
21284 This is a list of @dfn{module packages} loaded by the Xorg
21285 server---e.g., @code{xf86-video-vesa}, @code{xf86-input-keyboard}, and so on.
21287 @item @code{fonts} (default: @code{%default-xorg-fonts})
21288 This is a list of font directories to add to the server's @dfn{font path}.
21290 @item @code{drivers} (default: @code{'()})
21291 This must be either the empty list, in which case Xorg chooses a graphics
21292 driver automatically, or a list of driver names that will be tried in this
21293 order---e.g., @code{("modesetting" "vesa")}.
21295 @item @code{resolutions} (default: @code{'()})
21296 When @code{resolutions} is the empty list, Xorg chooses an appropriate screen
21297 resolution. Otherwise, it must be a list of resolutions---e.g., @code{((1024
21300 @cindex keyboard layout, for Xorg
21301 @cindex keymap, for Xorg
21302 @item @code{keyboard-layout} (default: @code{#f})
21303 If this is @code{#f}, Xorg uses the default keyboard layout---usually US
21304 English (``qwerty'') for a 105-key PC keyboard.
21306 Otherwise this must be a @code{keyboard-layout} object specifying the keyboard
21307 layout in use when Xorg is running. @xref{Keyboard Layout}, for more
21308 information on how to specify the keyboard layout.
21310 @item @code{extra-config} (default: @code{'()})
21311 This is a list of strings or objects appended to the configuration file. It
21312 is used to pass extra text to be added verbatim to the configuration file.
21314 @item @code{server} (default: @code{xorg-server})
21315 This is the package providing the Xorg server.
21317 @item @code{server-arguments} (default: @code{%default-xorg-server-arguments})
21318 This is the list of command-line arguments to pass to the X server. The
21319 default is @code{-nolisten tcp}.
21323 @deffn {Scheme Procedure} set-xorg-configuration @var{config} @
21324 [@var{login-manager-service-type}]
21325 Tell the log-in manager (of type @var{login-manager-service-type}) to use
21326 @var{config}, an @code{<xorg-configuration>} record.
21328 Since the Xorg configuration is embedded in the log-in manager's
21329 configuration---e.g., @code{gdm-configuration}---this procedure provides a
21330 shorthand to set the Xorg configuration.
21333 @deffn {Scheme Procedure} xorg-start-command [@var{config}]
21334 Return a @code{startx} script in which the modules, fonts, etc. specified
21335 in @var{config}, are available. The result should be used in place of
21338 Usually the X server is started by a login manager.
21342 @deffn {Scheme Procedure} screen-locker-service @var{package} [@var{program}]
21343 Add @var{package}, a package for a screen locker or screen saver whose
21344 command is @var{program}, to the set of setuid programs and add a PAM entry
21345 for it. For example:
21348 (screen-locker-service xlockmore "xlock")
21351 makes the good ol' XlockMore usable.
21355 @node Printing Services
21356 @subsection Printing Services
21358 @cindex printer support with CUPS
21359 The @code{(gnu services cups)} module provides a Guix service definition
21360 for the CUPS printing service. To add printer support to a Guix
21361 system, add a @code{cups-service} to the operating system definition:
21363 @deffn {Scheme Variable} cups-service-type
21364 The service type for the CUPS print server. Its value should be a valid
21365 CUPS configuration (see below). To use the default settings, simply
21368 (service cups-service-type)
21372 The CUPS configuration controls the basic things about your CUPS
21373 installation: what interfaces it listens on, what to do if a print job
21374 fails, how much logging to do, and so on. To actually add a printer,
21375 you have to visit the @url{http://localhost:631} URL, or use a tool such
21376 as GNOME's printer configuration services. By default, configuring a
21377 CUPS service will generate a self-signed certificate if needed, for
21378 secure connections to the print server.
21380 Suppose you want to enable the Web interface of CUPS and also add
21381 support for Epson printers @i{via} the @code{epson-inkjet-printer-escpr}
21382 package and for HP printers @i{via} the @code{hplip-minimal} package.
21383 You can do that directly, like this (you need to use the
21384 @code{(gnu packages cups)} module):
21387 (service cups-service-type
21388 (cups-configuration
21389 (web-interface? #t)
21391 (list cups-filters epson-inkjet-printer-escpr hplip-minimal))))
21395 If you wish to use the Qt5 based GUI which comes with the hplip
21396 package then it is suggested that you install the @code{hplip} package,
21397 either in your OS configuration file or as your user.
21400 The available configuration parameters follow. Each parameter
21401 definition is preceded by its type; for example, @samp{string-list foo}
21402 indicates that the @code{foo} parameter should be specified as a list of
21403 strings. There is also a way to specify the configuration as a string,
21404 if you have an old @code{cupsd.conf} file that you want to port over
21405 from some other system; see the end for more details.
21407 @c The following documentation was initially generated by
21408 @c (generate-documentation) in (gnu services cups). Manually maintained
21409 @c documentation is better, so we shouldn't hesitate to edit below as
21410 @c needed. However if the change you want to make to this documentation
21411 @c can be done in an automated way, it's probably easier to change
21412 @c (generate-documentation) than to make it below and have to deal with
21413 @c the churn as CUPS updates.
21416 Available @code{cups-configuration} fields are:
21418 @deftypevr {@code{cups-configuration} parameter} package cups
21422 @deftypevr {@code{cups-configuration} parameter} package-list extensions (default: @code{(list brlaser cups-filters epson-inkjet-printer-escpr foomatic-filters hplip-minimal splix)})
21423 Drivers and other extensions to the CUPS package.
21426 @deftypevr {@code{cups-configuration} parameter} files-configuration files-configuration
21427 Configuration of where to write logs, what directories to use for print
21428 spools, and related privileged configuration parameters.
21430 Available @code{files-configuration} fields are:
21432 @deftypevr {@code{files-configuration} parameter} log-location access-log
21433 Defines the access log filename. Specifying a blank filename disables
21434 access log generation. The value @code{stderr} causes log entries to be
21435 sent to the standard error file when the scheduler is running in the
21436 foreground, or to the system log daemon when run in the background. The
21437 value @code{syslog} causes log entries to be sent to the system log
21438 daemon. The server name may be included in filenames using the string
21439 @code{%s}, as in @code{/var/log/cups/%s-access_log}.
21441 Defaults to @samp{"/var/log/cups/access_log"}.
21444 @deftypevr {@code{files-configuration} parameter} file-name cache-dir
21445 Where CUPS should cache data.
21447 Defaults to @samp{"/var/cache/cups"}.
21450 @deftypevr {@code{files-configuration} parameter} string config-file-perm
21451 Specifies the permissions for all configuration files that the scheduler
21454 Note that the permissions for the printers.conf file are currently
21455 masked to only allow access from the scheduler user (typically root).
21456 This is done because printer device URIs sometimes contain sensitive
21457 authentication information that should not be generally known on the
21458 system. There is no way to disable this security feature.
21460 Defaults to @samp{"0640"}.
21463 @deftypevr {@code{files-configuration} parameter} log-location error-log
21464 Defines the error log filename. Specifying a blank filename disables
21465 error log generation. The value @code{stderr} causes log entries to be
21466 sent to the standard error file when the scheduler is running in the
21467 foreground, or to the system log daemon when run in the background. The
21468 value @code{syslog} causes log entries to be sent to the system log
21469 daemon. The server name may be included in filenames using the string
21470 @code{%s}, as in @code{/var/log/cups/%s-error_log}.
21472 Defaults to @samp{"/var/log/cups/error_log"}.
21475 @deftypevr {@code{files-configuration} parameter} string fatal-errors
21476 Specifies which errors are fatal, causing the scheduler to exit. The
21481 No errors are fatal.
21484 All of the errors below are fatal.
21487 Browsing initialization errors are fatal, for example failed connections
21488 to the DNS-SD daemon.
21491 Configuration file syntax errors are fatal.
21494 Listen or Port errors are fatal, except for IPv6 failures on the
21495 loopback or @code{any} addresses.
21498 Log file creation or write errors are fatal.
21501 Bad startup file permissions are fatal, for example shared TLS
21502 certificate and key files with world-read permissions.
21505 Defaults to @samp{"all -browse"}.
21508 @deftypevr {@code{files-configuration} parameter} boolean file-device?
21509 Specifies whether the file pseudo-device can be used for new printer
21510 queues. The URI @uref{file:///dev/null} is always allowed.
21512 Defaults to @samp{#f}.
21515 @deftypevr {@code{files-configuration} parameter} string group
21516 Specifies the group name or ID that will be used when executing external
21519 Defaults to @samp{"lp"}.
21522 @deftypevr {@code{files-configuration} parameter} string log-file-group
21523 Specifies the group name or ID that will be used for log files.
21525 Defaults to @samp{"lpadmin"}.
21528 @deftypevr {@code{files-configuration} parameter} string log-file-perm
21529 Specifies the permissions for all log files that the scheduler writes.
21531 Defaults to @samp{"0644"}.
21534 @deftypevr {@code{files-configuration} parameter} log-location page-log
21535 Defines the page log filename. Specifying a blank filename disables
21536 page log generation. The value @code{stderr} causes log entries to be
21537 sent to the standard error file when the scheduler is running in the
21538 foreground, or to the system log daemon when run in the background. The
21539 value @code{syslog} causes log entries to be sent to the system log
21540 daemon. The server name may be included in filenames using the string
21541 @code{%s}, as in @code{/var/log/cups/%s-page_log}.
21543 Defaults to @samp{"/var/log/cups/page_log"}.
21546 @deftypevr {@code{files-configuration} parameter} string remote-root
21547 Specifies the username that is associated with unauthenticated accesses
21548 by clients claiming to be the root user. The default is @code{remroot}.
21550 Defaults to @samp{"remroot"}.
21553 @deftypevr {@code{files-configuration} parameter} file-name request-root
21554 Specifies the directory that contains print jobs and other HTTP request
21557 Defaults to @samp{"/var/spool/cups"}.
21560 @deftypevr {@code{files-configuration} parameter} sandboxing sandboxing
21561 Specifies the level of security sandboxing that is applied to print
21562 filters, backends, and other child processes of the scheduler; either
21563 @code{relaxed} or @code{strict}. This directive is currently only
21564 used/supported on macOS.
21566 Defaults to @samp{strict}.
21569 @deftypevr {@code{files-configuration} parameter} file-name server-keychain
21570 Specifies the location of TLS certificates and private keys. CUPS will
21571 look for public and private keys in this directory: @file{.crt} files
21572 for PEM-encoded certificates and corresponding @file{.key} files for
21573 PEM-encoded private keys.
21575 Defaults to @samp{"/etc/cups/ssl"}.
21578 @deftypevr {@code{files-configuration} parameter} file-name server-root
21579 Specifies the directory containing the server configuration files.
21581 Defaults to @samp{"/etc/cups"}.
21584 @deftypevr {@code{files-configuration} parameter} boolean sync-on-close?
21585 Specifies whether the scheduler calls fsync(2) after writing
21586 configuration or state files.
21588 Defaults to @samp{#f}.
21591 @deftypevr {@code{files-configuration} parameter} space-separated-string-list system-group
21592 Specifies the group(s) to use for @code{@@SYSTEM} group authentication.
21595 @deftypevr {@code{files-configuration} parameter} file-name temp-dir
21596 Specifies the directory where temporary files are stored.
21598 Defaults to @samp{"/var/spool/cups/tmp"}.
21601 @deftypevr {@code{files-configuration} parameter} string user
21602 Specifies the user name or ID that is used when running external
21605 Defaults to @samp{"lp"}.
21608 @deftypevr {@code{files-configuration} parameter} string set-env
21609 Set the specified environment variable to be passed to child processes.
21611 Defaults to @samp{"variable value"}.
21615 @deftypevr {@code{cups-configuration} parameter} access-log-level access-log-level
21616 Specifies the logging level for the AccessLog file. The @code{config}
21617 level logs when printers and classes are added, deleted, or modified and
21618 when configuration files are accessed or updated. The @code{actions}
21619 level logs when print jobs are submitted, held, released, modified, or
21620 canceled, and any of the conditions for @code{config}. The @code{all}
21621 level logs all requests.
21623 Defaults to @samp{actions}.
21626 @deftypevr {@code{cups-configuration} parameter} boolean auto-purge-jobs?
21627 Specifies whether to purge job history data automatically when it is no
21628 longer required for quotas.
21630 Defaults to @samp{#f}.
21633 @deftypevr {@code{cups-configuration} parameter} comma-separated-string-list browse-dns-sd-sub-types
21634 Specifies a list of DNS-SD sub-types to advertise for each shared printer.
21635 For example, @samp{"_cups" "_print"} will tell network clients that both
21636 CUPS sharing and IPP Everywhere are supported.
21638 Defaults to @samp{"_cups"}.
21641 @deftypevr {@code{cups-configuration} parameter} browse-local-protocols browse-local-protocols
21642 Specifies which protocols to use for local printer sharing.
21644 Defaults to @samp{dnssd}.
21647 @deftypevr {@code{cups-configuration} parameter} boolean browse-web-if?
21648 Specifies whether the CUPS web interface is advertised.
21650 Defaults to @samp{#f}.
21653 @deftypevr {@code{cups-configuration} parameter} boolean browsing?
21654 Specifies whether shared printers are advertised.
21656 Defaults to @samp{#f}.
21659 @deftypevr {@code{cups-configuration} parameter} string classification
21660 Specifies the security classification of the server. Any valid banner
21661 name can be used, including @samp{"classified"}, @samp{"confidential"},
21662 @samp{"secret"}, @samp{"topsecret"}, and @samp{"unclassified"}, or the
21663 banner can be omitted to disable secure printing functions.
21665 Defaults to @samp{""}.
21668 @deftypevr {@code{cups-configuration} parameter} boolean classify-override?
21669 Specifies whether users may override the classification (cover page) of
21670 individual print jobs using the @code{job-sheets} option.
21672 Defaults to @samp{#f}.
21675 @deftypevr {@code{cups-configuration} parameter} default-auth-type default-auth-type
21676 Specifies the default type of authentication to use.
21678 Defaults to @samp{Basic}.
21681 @deftypevr {@code{cups-configuration} parameter} default-encryption default-encryption
21682 Specifies whether encryption will be used for authenticated requests.
21684 Defaults to @samp{Required}.
21687 @deftypevr {@code{cups-configuration} parameter} string default-language
21688 Specifies the default language to use for text and web content.
21690 Defaults to @samp{"en"}.
21693 @deftypevr {@code{cups-configuration} parameter} string default-paper-size
21694 Specifies the default paper size for new print queues. @samp{"Auto"}
21695 uses a locale-specific default, while @samp{"None"} specifies there is
21696 no default paper size. Specific size names are typically
21697 @samp{"Letter"} or @samp{"A4"}.
21699 Defaults to @samp{"Auto"}.
21702 @deftypevr {@code{cups-configuration} parameter} string default-policy
21703 Specifies the default access policy to use.
21705 Defaults to @samp{"default"}.
21708 @deftypevr {@code{cups-configuration} parameter} boolean default-shared?
21709 Specifies whether local printers are shared by default.
21711 Defaults to @samp{#t}.
21714 @deftypevr {@code{cups-configuration} parameter} non-negative-integer dirty-clean-interval
21715 Specifies the delay for updating of configuration and state files, in
21716 seconds. A value of 0 causes the update to happen as soon as possible,
21717 typically within a few milliseconds.
21719 Defaults to @samp{30}.
21722 @deftypevr {@code{cups-configuration} parameter} error-policy error-policy
21723 Specifies what to do when an error occurs. Possible values are
21724 @code{abort-job}, which will discard the failed print job;
21725 @code{retry-job}, which will retry the job at a later time;
21726 @code{retry-current-job}, which retries the failed job immediately; and
21727 @code{stop-printer}, which stops the printer.
21729 Defaults to @samp{stop-printer}.
21732 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-limit
21733 Specifies the maximum cost of filters that are run concurrently, which
21734 can be used to minimize disk, memory, and CPU resource problems. A
21735 limit of 0 disables filter limiting. An average print to a
21736 non-PostScript printer needs a filter limit of about 200. A PostScript
21737 printer needs about half that (100). Setting the limit below these
21738 thresholds will effectively limit the scheduler to printing a single job
21741 Defaults to @samp{0}.
21744 @deftypevr {@code{cups-configuration} parameter} non-negative-integer filter-nice
21745 Specifies the scheduling priority of filters that are run to print a
21746 job. The nice value ranges from 0, the highest priority, to 19, the
21749 Defaults to @samp{0}.
21752 @deftypevr {@code{cups-configuration} parameter} host-name-lookups host-name-lookups
21753 Specifies whether to do reverse lookups on connecting clients. The
21754 @code{double} setting causes @code{cupsd} to verify that the hostname
21755 resolved from the address matches one of the addresses returned for that
21756 hostname. Double lookups also prevent clients with unregistered
21757 addresses from connecting to your server. Only set this option to
21758 @code{#t} or @code{double} if absolutely required.
21760 Defaults to @samp{#f}.
21763 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-kill-delay
21764 Specifies the number of seconds to wait before killing the filters and
21765 backend associated with a canceled or held job.
21767 Defaults to @samp{30}.
21770 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-interval
21771 Specifies the interval between retries of jobs in seconds. This is
21772 typically used for fax queues but can also be used with normal print
21773 queues whose error policy is @code{retry-job} or
21774 @code{retry-current-job}.
21776 Defaults to @samp{30}.
21779 @deftypevr {@code{cups-configuration} parameter} non-negative-integer job-retry-limit
21780 Specifies the number of retries that are done for jobs. This is
21781 typically used for fax queues but can also be used with normal print
21782 queues whose error policy is @code{retry-job} or
21783 @code{retry-current-job}.
21785 Defaults to @samp{5}.
21788 @deftypevr {@code{cups-configuration} parameter} boolean keep-alive?
21789 Specifies whether to support HTTP keep-alive connections.
21791 Defaults to @samp{#t}.
21794 @deftypevr {@code{cups-configuration} parameter} non-negative-integer limit-request-body
21795 Specifies the maximum size of print files, IPP requests, and HTML form
21796 data. A limit of 0 disables the limit check.
21798 Defaults to @samp{0}.
21801 @deftypevr {@code{cups-configuration} parameter} multiline-string-list listen
21802 Listens on the specified interfaces for connections. Valid values are
21803 of the form @var{address}:@var{port}, where @var{address} is either an
21804 IPv6 address enclosed in brackets, an IPv4 address, or @code{*} to
21805 indicate all addresses. Values can also be file names of local UNIX
21806 domain sockets. The Listen directive is similar to the Port directive
21807 but allows you to restrict access to specific interfaces or networks.
21810 @deftypevr {@code{cups-configuration} parameter} non-negative-integer listen-back-log
21811 Specifies the number of pending connections that will be allowed. This
21812 normally only affects very busy servers that have reached the MaxClients
21813 limit, but can also be triggered by large numbers of simultaneous
21814 connections. When the limit is reached, the operating system will
21815 refuse additional connections until the scheduler can accept the pending
21818 Defaults to @samp{128}.
21821 @deftypevr {@code{cups-configuration} parameter} location-access-control-list location-access-controls
21822 Specifies a set of additional access controls.
21824 Available @code{location-access-controls} fields are:
21826 @deftypevr {@code{location-access-controls} parameter} file-name path
21827 Specifies the URI path to which the access control applies.
21830 @deftypevr {@code{location-access-controls} parameter} access-control-list access-controls
21831 Access controls for all access to this path, in the same format as the
21832 @code{access-controls} of @code{operation-access-control}.
21834 Defaults to @samp{()}.
21837 @deftypevr {@code{location-access-controls} parameter} method-access-control-list method-access-controls
21838 Access controls for method-specific access to this path.
21840 Defaults to @samp{()}.
21842 Available @code{method-access-controls} fields are:
21844 @deftypevr {@code{method-access-controls} parameter} boolean reverse?
21845 If @code{#t}, apply access controls to all methods except the listed
21846 methods. Otherwise apply to only the listed methods.
21848 Defaults to @samp{#f}.
21851 @deftypevr {@code{method-access-controls} parameter} method-list methods
21852 Methods to which this access control applies.
21854 Defaults to @samp{()}.
21857 @deftypevr {@code{method-access-controls} parameter} access-control-list access-controls
21858 Access control directives, as a list of strings. Each string should be
21859 one directive, such as @samp{"Order allow,deny"}.
21861 Defaults to @samp{()}.
21866 @deftypevr {@code{cups-configuration} parameter} non-negative-integer log-debug-history
21867 Specifies the number of debugging messages that are retained for logging
21868 if an error occurs in a print job. Debug messages are logged regardless
21869 of the LogLevel setting.
21871 Defaults to @samp{100}.
21874 @deftypevr {@code{cups-configuration} parameter} log-level log-level
21875 Specifies the level of logging for the ErrorLog file. The value
21876 @code{none} stops all logging while @code{debug2} logs everything.
21878 Defaults to @samp{info}.
21881 @deftypevr {@code{cups-configuration} parameter} log-time-format log-time-format
21882 Specifies the format of the date and time in the log files. The value
21883 @code{standard} logs whole seconds while @code{usecs} logs microseconds.
21885 Defaults to @samp{standard}.
21888 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients
21889 Specifies the maximum number of simultaneous clients that are allowed by
21892 Defaults to @samp{100}.
21895 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-clients-per-host
21896 Specifies the maximum number of simultaneous clients that are allowed
21897 from a single address.
21899 Defaults to @samp{100}.
21902 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-copies
21903 Specifies the maximum number of copies that a user can print of each
21906 Defaults to @samp{9999}.
21909 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-hold-time
21910 Specifies the maximum time a job may remain in the @code{indefinite}
21911 hold state before it is canceled. A value of 0 disables cancellation of
21914 Defaults to @samp{0}.
21917 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs
21918 Specifies the maximum number of simultaneous jobs that are allowed. Set
21919 to 0 to allow an unlimited number of jobs.
21921 Defaults to @samp{500}.
21924 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-printer
21925 Specifies the maximum number of simultaneous jobs that are allowed per
21926 printer. A value of 0 allows up to MaxJobs jobs per printer.
21928 Defaults to @samp{0}.
21931 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-jobs-per-user
21932 Specifies the maximum number of simultaneous jobs that are allowed per
21933 user. A value of 0 allows up to MaxJobs jobs per user.
21935 Defaults to @samp{0}.
21938 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-job-time
21939 Specifies the maximum time a job may take to print before it is
21940 canceled, in seconds. Set to 0 to disable cancellation of ``stuck'' jobs.
21942 Defaults to @samp{10800}.
21945 @deftypevr {@code{cups-configuration} parameter} non-negative-integer max-log-size
21946 Specifies the maximum size of the log files before they are rotated, in
21947 bytes. The value 0 disables log rotation.
21949 Defaults to @samp{1048576}.
21952 @deftypevr {@code{cups-configuration} parameter} non-negative-integer multiple-operation-timeout
21953 Specifies the maximum amount of time to allow between files in a
21954 multiple file print job, in seconds.
21956 Defaults to @samp{900}.
21959 @deftypevr {@code{cups-configuration} parameter} string page-log-format
21960 Specifies the format of PageLog lines. Sequences beginning with percent
21961 (@samp{%}) characters are replaced with the corresponding information,
21962 while all other characters are copied literally. The following percent
21963 sequences are recognized:
21967 insert a single percent character
21970 insert the value of the specified IPP attribute
21973 insert the number of copies for the current page
21976 insert the current page number
21979 insert the current date and time in common log format
21985 insert the printer name
21988 insert the username
21991 A value of the empty string disables page logging. The string @code{%p
21992 %u %j %T %P %C %@{job-billing@} %@{job-originating-host-name@}
21993 %@{job-name@} %@{media@} %@{sides@}} creates a page log with the
21996 Defaults to @samp{""}.
21999 @deftypevr {@code{cups-configuration} parameter} environment-variables environment-variables
22000 Passes the specified environment variable(s) to child processes; a list
22003 Defaults to @samp{()}.
22006 @deftypevr {@code{cups-configuration} parameter} policy-configuration-list policies
22007 Specifies named access control policies.
22009 Available @code{policy-configuration} fields are:
22011 @deftypevr {@code{policy-configuration} parameter} string name
22012 Name of the policy.
22015 @deftypevr {@code{policy-configuration} parameter} string job-private-access
22016 Specifies an access list for a job's private values. @code{@@ACL} maps
22017 to the printer's requesting-user-name-allowed or
22018 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
22019 owner. @code{@@SYSTEM} maps to the groups listed for the
22020 @code{system-group} field of the @code{files-configuration},
22021 which is reified into the @code{cups-files.conf(5)} file. Other
22022 possible elements of the access list include specific user names, and
22023 @code{@@@var{group}} to indicate members of a specific group. The
22024 access list may also be simply @code{all} or @code{default}.
22026 Defaults to @samp{"@@OWNER @@SYSTEM"}.
22029 @deftypevr {@code{policy-configuration} parameter} string job-private-values
22030 Specifies the list of job values to make private, or @code{all},
22031 @code{default}, or @code{none}.
22033 Defaults to @samp{"job-name job-originating-host-name
22034 job-originating-user-name phone"}.
22037 @deftypevr {@code{policy-configuration} parameter} string subscription-private-access
22038 Specifies an access list for a subscription's private values.
22039 @code{@@ACL} maps to the printer's requesting-user-name-allowed or
22040 requesting-user-name-denied values. @code{@@OWNER} maps to the job's
22041 owner. @code{@@SYSTEM} maps to the groups listed for the
22042 @code{system-group} field of the @code{files-configuration},
22043 which is reified into the @code{cups-files.conf(5)} file. Other
22044 possible elements of the access list include specific user names, and
22045 @code{@@@var{group}} to indicate members of a specific group. The
22046 access list may also be simply @code{all} or @code{default}.
22048 Defaults to @samp{"@@OWNER @@SYSTEM"}.
22051 @deftypevr {@code{policy-configuration} parameter} string subscription-private-values
22052 Specifies the list of job values to make private, or @code{all},
22053 @code{default}, or @code{none}.
22055 Defaults to @samp{"notify-events notify-pull-method notify-recipient-uri
22056 notify-subscriber-user-name notify-user-data"}.
22059 @deftypevr {@code{policy-configuration} parameter} operation-access-control-list access-controls
22060 Access control by IPP operation.
22062 Defaults to @samp{()}.
22066 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-files
22067 Specifies whether job files (documents) are preserved after a job is
22068 printed. If a numeric value is specified, job files are preserved for
22069 the indicated number of seconds after printing. Otherwise a boolean
22070 value applies indefinitely.
22072 Defaults to @samp{86400}.
22075 @deftypevr {@code{cups-configuration} parameter} boolean-or-non-negative-integer preserve-job-history
22076 Specifies whether the job history is preserved after a job is printed.
22077 If a numeric value is specified, the job history is preserved for the
22078 indicated number of seconds after printing. If @code{#t}, the job
22079 history is preserved until the MaxJobs limit is reached.
22081 Defaults to @samp{#t}.
22084 @deftypevr {@code{cups-configuration} parameter} non-negative-integer reload-timeout
22085 Specifies the amount of time to wait for job completion before
22086 restarting the scheduler.
22088 Defaults to @samp{30}.
22091 @deftypevr {@code{cups-configuration} parameter} string rip-cache
22092 Specifies the maximum amount of memory to use when converting documents
22093 into bitmaps for a printer.
22095 Defaults to @samp{"128m"}.
22098 @deftypevr {@code{cups-configuration} parameter} string server-admin
22099 Specifies the email address of the server administrator.
22101 Defaults to @samp{"root@@localhost.localdomain"}.
22104 @deftypevr {@code{cups-configuration} parameter} host-name-list-or-* server-alias
22105 The ServerAlias directive is used for HTTP Host header validation when
22106 clients connect to the scheduler from external interfaces. Using the
22107 special name @code{*} can expose your system to known browser-based DNS
22108 rebinding attacks, even when accessing sites through a firewall. If the
22109 auto-discovery of alternate names does not work, we recommend listing
22110 each alternate name with a ServerAlias directive instead of using
22113 Defaults to @samp{*}.
22116 @deftypevr {@code{cups-configuration} parameter} string server-name
22117 Specifies the fully-qualified host name of the server.
22119 Defaults to @samp{"localhost"}.
22122 @deftypevr {@code{cups-configuration} parameter} server-tokens server-tokens
22123 Specifies what information is included in the Server header of HTTP
22124 responses. @code{None} disables the Server header. @code{ProductOnly}
22125 reports @code{CUPS}. @code{Major} reports @code{CUPS 2}. @code{Minor}
22126 reports @code{CUPS 2.0}. @code{Minimal} reports @code{CUPS 2.0.0}.
22127 @code{OS} reports @code{CUPS 2.0.0 (@var{uname})} where @var{uname} is
22128 the output of the @code{uname} command. @code{Full} reports @code{CUPS
22129 2.0.0 (@var{uname}) IPP/2.0}.
22131 Defaults to @samp{Minimal}.
22134 @deftypevr {@code{cups-configuration} parameter} multiline-string-list ssl-listen
22135 Listens on the specified interfaces for encrypted connections. Valid
22136 values are of the form @var{address}:@var{port}, where @var{address} is
22137 either an IPv6 address enclosed in brackets, an IPv4 address, or
22138 @code{*} to indicate all addresses.
22140 Defaults to @samp{()}.
22143 @deftypevr {@code{cups-configuration} parameter} ssl-options ssl-options
22144 Sets encryption options. By default, CUPS only supports encryption
22145 using TLS v1.0 or higher using known secure cipher suites. Security is
22146 reduced when @code{Allow} options are used, and enhanced when @code{Deny}
22147 options are used. The @code{AllowRC4} option enables the 128-bit RC4 cipher
22148 suites, which are required for some older clients. The @code{AllowSSL3} option
22149 enables SSL v3.0, which is required for some older clients that do not support
22150 TLS v1.0. The @code{DenyCBC} option disables all CBC cipher suites. The
22151 @code{DenyTLS1.0} option disables TLS v1.0 support - this sets the minimum
22152 protocol version to TLS v1.1.
22154 Defaults to @samp{()}.
22157 @deftypevr {@code{cups-configuration} parameter} boolean strict-conformance?
22158 Specifies whether the scheduler requires clients to strictly adhere to
22159 the IPP specifications.
22161 Defaults to @samp{#f}.
22164 @deftypevr {@code{cups-configuration} parameter} non-negative-integer timeout
22165 Specifies the HTTP request timeout, in seconds.
22167 Defaults to @samp{900}.
22171 @deftypevr {@code{cups-configuration} parameter} boolean web-interface?
22172 Specifies whether the web interface is enabled.
22174 Defaults to @samp{#f}.
22177 At this point you're probably thinking ``oh dear, Guix manual, I like
22178 you but you can stop already with the configuration options''. Indeed.
22179 However, one more point: it could be that you have an existing
22180 @code{cupsd.conf} that you want to use. In that case, you can pass an
22181 @code{opaque-cups-configuration} as the configuration of a
22182 @code{cups-service-type}.
22184 Available @code{opaque-cups-configuration} fields are:
22186 @deftypevr {@code{opaque-cups-configuration} parameter} package cups
22190 @deftypevr {@code{opaque-cups-configuration} parameter} string cupsd.conf
22191 The contents of the @code{cupsd.conf}, as a string.
22194 @deftypevr {@code{opaque-cups-configuration} parameter} string cups-files.conf
22195 The contents of the @code{cups-files.conf} file, as a string.
22198 For example, if your @code{cupsd.conf} and @code{cups-files.conf} are in
22199 strings of the same name, you could instantiate a CUPS service like
22203 (service cups-service-type
22204 (opaque-cups-configuration
22205 (cupsd.conf cupsd.conf)
22206 (cups-files.conf cups-files.conf)))
22210 @node Desktop Services
22211 @subsection Desktop Services
22213 The @code{(gnu services desktop)} module provides services that are
22214 usually useful in the context of a ``desktop'' setup---that is, on a
22215 machine running a graphical display server, possibly with graphical user
22216 interfaces, etc. It also defines services that provide specific desktop
22217 environments like GNOME, Xfce or MATE.
22219 To simplify things, the module defines a variable containing the set of
22220 services that users typically expect on a machine with a graphical
22221 environment and networking:
22223 @defvr {Scheme Variable} %desktop-services
22224 This is a list of services that builds upon @code{%base-services} and
22225 adds or adjusts services for a typical ``desktop'' setup.
22227 In particular, it adds a graphical login manager (@pxref{X Window,
22228 @code{gdm-service-type}}), screen lockers, a network management tool
22229 (@pxref{Networking Services, @code{network-manager-service-type}}) with modem
22230 support (@pxref{Networking Services, @code{modem-manager-service-type}}),
22231 energy and color management services, the @code{elogind} login and seat
22232 manager, the Polkit privilege service, the GeoClue location service, the
22233 AccountsService daemon that allows authorized users change system passwords,
22234 an NTP client (@pxref{Networking Services}), the Avahi daemon, and has the
22235 name service switch service configured to be able to use @code{nss-mdns}
22236 (@pxref{Name Service Switch, mDNS}).
22239 The @code{%desktop-services} variable can be used as the @code{services}
22240 field of an @code{operating-system} declaration (@pxref{operating-system
22241 Reference, @code{services}}).
22243 Additionally, the @code{gnome-desktop-service-type},
22244 @code{xfce-desktop-service}, @code{mate-desktop-service-type},
22245 @code{lxqt-desktop-service-type} and @code{enlightenment-desktop-service-type}
22246 procedures can add GNOME, Xfce, MATE and/or Enlightenment to a system. To
22247 ``add GNOME'' means that system-level services like the backlight adjustment
22248 helpers and the power management utilities are added to the system, extending
22249 @code{polkit} and @code{dbus} appropriately, allowing GNOME to operate with
22250 elevated privileges on a limited number of special-purpose system interfaces.
22251 Additionally, adding a service made by @code{gnome-desktop-service-type} adds
22252 the GNOME metapackage to the system profile. Likewise, adding the Xfce
22253 service not only adds the @code{xfce} metapackage to the system profile, but
22254 it also gives the Thunar file manager the ability to open a ``root-mode'' file
22255 management window, if the user authenticates using the administrator's
22256 password via the standard polkit graphical interface. To ``add MATE'' means
22257 that @code{polkit} and @code{dbus} are extended appropriately, allowing MATE
22258 to operate with elevated privileges on a limited number of special-purpose
22259 system interfaces. Additionally, adding a service of type
22260 @code{mate-desktop-service-type} adds the MATE metapackage to the system
22261 profile. ``Adding Enlightenment'' means that @code{dbus} is extended
22262 appropriately, and several of Enlightenment's binaries are set as setuid,
22263 allowing Enlightenment's screen locker and other functionality to work as
22266 The desktop environments in Guix use the Xorg display server by
22267 default. If you'd like to use the newer display server protocol
22268 called Wayland, you need to enable Wayland support in GDM
22269 (@pxref{wayland-gdm}). Another solution is to use the
22270 @code{sddm-service} instead of GDM as the graphical login manager.
22271 You should then select the ``GNOME (Wayland)'' session in SDDM@.
22272 Alternatively you can also try starting GNOME on Wayland manually from a
22273 TTY with the command ``XDG_SESSION_TYPE=wayland exec dbus-run-session
22274 gnome-session``. Currently only GNOME has support for Wayland.
22276 @defvr {Scheme Variable} gnome-desktop-service-type
22277 This is the type of the service that adds the @uref{https://www.gnome.org,
22278 GNOME} desktop environment. Its value is a @code{gnome-desktop-configuration}
22279 object (see below).
22281 This service adds the @code{gnome} package to the system profile, and extends
22282 polkit with the actions from @code{gnome-settings-daemon}.
22285 @deftp {Data Type} gnome-desktop-configuration
22286 Configuration record for the GNOME desktop environment.
22289 @item @code{gnome} (default: @code{gnome})
22290 The GNOME package to use.
22294 @defvr {Scheme Variable} xfce-desktop-service-type
22295 This is the type of a service to run the @uref{Xfce, https://xfce.org/}
22296 desktop environment. Its value is an @code{xfce-desktop-configuration} object
22299 This service adds the @code{xfce} package to the system profile, and
22300 extends polkit with the ability for @code{thunar} to manipulate the file
22301 system as root from within a user session, after the user has authenticated
22302 with the administrator's password.
22304 Note that @code{xfce4-panel} and its plugin packages should be installed in
22305 the same profile to ensure compatibility. When using this service, you should
22306 add extra plugins (@code{xfce4-whiskermenu-plugin},
22307 @code{xfce4-weather-plugin}, etc.) to the @code{packages} field of your
22308 @code{operating-system}.
22311 @deftp {Data Type} xfce-desktop-configuration
22312 Configuration record for the Xfce desktop environment.
22315 @item @code{xfce} (default: @code{xfce})
22316 The Xfce package to use.
22320 @deffn {Scheme Variable} mate-desktop-service-type
22321 This is the type of the service that runs the @uref{https://mate-desktop.org/,
22322 MATE desktop environment}. Its value is a @code{mate-desktop-configuration}
22323 object (see below).
22325 This service adds the @code{mate} package to the system
22326 profile, and extends polkit with the actions from
22327 @code{mate-settings-daemon}.
22330 @deftp {Data Type} mate-desktop-configuration
22331 Configuration record for the MATE desktop environment.
22334 @item @code{mate} (default: @code{mate})
22335 The MATE package to use.
22339 @deffn {Scheme Variable} lxqt-desktop-service-type
22340 This is the type of the service that runs the @uref{https://lxqt-project.org,
22341 LXQt desktop environment}. Its value is a @code{lxqt-desktop-configuration}
22342 object (see below).
22344 This service adds the @code{lxqt} package to the system
22348 @deftp {Data Type} lxqt-desktop-configuration
22349 Configuration record for the LXQt desktop environment.
22352 @item @code{lxqt} (default: @code{lxqt})
22353 The LXQT package to use.
22357 @deffn {Scheme Variable} enlightenment-desktop-service-type
22358 Return a service that adds the @code{enlightenment} package to the system
22359 profile, and extends dbus with actions from @code{efl}.
22362 @deftp {Data Type} enlightenment-desktop-service-configuration
22364 @item @code{enlightenment} (default: @code{enlightenment})
22365 The enlightenment package to use.
22369 Because the GNOME, Xfce and MATE desktop services pull in so many packages,
22370 the default @code{%desktop-services} variable doesn't include any of
22371 them by default. To add GNOME, Xfce or MATE, just @code{cons} them onto
22372 @code{%desktop-services} in the @code{services} field of your
22373 @code{operating-system}:
22376 (use-modules (gnu))
22377 (use-service-modules desktop)
22380 ;; cons* adds items to the list given as its last argument.
22381 (services (cons* (service gnome-desktop-service-type)
22382 (service xfce-desktop-service)
22383 %desktop-services))
22387 These desktop environments will then be available as options in the
22388 graphical login window.
22390 The actual service definitions included in @code{%desktop-services} and
22391 provided by @code{(gnu services dbus)} and @code{(gnu services desktop)}
22392 are described below.
22394 @deffn {Scheme Procedure} dbus-service [#:dbus @var{dbus}] [#:services '()] @
22396 Return a service that runs the ``system bus'', using @var{dbus}, with
22397 support for @var{services}. When @var{verbose?} is true, it causes the
22398 @samp{DBUS_VERBOSE} environment variable to be set to @samp{1}; a
22399 verbose-enabled D-Bus package such as @code{dbus-verbose} should be
22400 provided as @var{dbus} in this scenario. The verbose output is logged
22401 to @file{/var/log/dbus-daemon.log}.
22403 @uref{https://dbus.freedesktop.org/, D-Bus} is an inter-process communication
22404 facility. Its system bus is used to allow system services to communicate
22405 and to be notified of system-wide events.
22407 @var{services} must be a list of packages that provide an
22408 @file{etc/dbus-1/system.d} directory containing additional D-Bus configuration
22409 and policy files. For example, to allow avahi-daemon to use the system bus,
22410 @var{services} must be equal to @code{(list avahi)}.
22413 @deffn {Scheme Procedure} elogind-service [#:config @var{config}]
22414 Return a service that runs the @code{elogind} login and
22415 seat management daemon. @uref{https://github.com/elogind/elogind,
22416 Elogind} exposes a D-Bus interface that can be used to know which users
22417 are logged in, know what kind of sessions they have open, suspend the
22418 system, inhibit system suspend, reboot the system, and other tasks.
22420 Elogind handles most system-level power events for a computer, for
22421 example suspending the system when a lid is closed, or shutting it down
22422 when the power button is pressed.
22424 The @var{config} keyword argument specifies the configuration for
22425 elogind, and should be the result of an @code{(elogind-configuration
22426 (@var{parameter} @var{value})...)} invocation. Available parameters and
22427 their default values are:
22430 @item kill-user-processes?
22432 @item kill-only-users
22434 @item kill-exclude-users
22436 @item inhibit-delay-max-seconds
22438 @item handle-power-key
22440 @item handle-suspend-key
22442 @item handle-hibernate-key
22444 @item handle-lid-switch
22446 @item handle-lid-switch-docked
22448 @item handle-lid-switch-external-power
22449 @code{*unspecified*}
22450 @item power-key-ignore-inhibited?
22452 @item suspend-key-ignore-inhibited?
22454 @item hibernate-key-ignore-inhibited?
22456 @item lid-switch-ignore-inhibited?
22458 @item holdoff-timeout-seconds
22462 @item idle-action-seconds
22464 @item runtime-directory-size-percent
22466 @item runtime-directory-size
22470 @item suspend-state
22471 @code{("mem" "standby" "freeze")}
22474 @item hibernate-state
22476 @item hibernate-mode
22477 @code{("platform" "shutdown")}
22478 @item hybrid-sleep-state
22480 @item hybrid-sleep-mode
22481 @code{("suspend" "platform" "shutdown")}
22485 @deffn {Scheme Procedure} accountsservice-service @
22486 [#:accountsservice @var{accountsservice}]
22487 Return a service that runs AccountsService, a system service that can
22488 list available accounts, change their passwords, and so on.
22489 AccountsService integrates with PolicyKit to enable unprivileged users
22490 to acquire the capability to modify their system configuration.
22491 @uref{https://www.freedesktop.org/wiki/Software/AccountsService/, the
22492 accountsservice web site} for more information.
22494 The @var{accountsservice} keyword argument is the @code{accountsservice}
22495 package to expose as a service.
22498 @deffn {Scheme Procedure} polkit-service @
22499 [#:polkit @var{polkit}]
22500 Return a service that runs the
22501 @uref{https://www.freedesktop.org/wiki/Software/polkit/, Polkit privilege
22502 management service}, which allows system administrators to grant access to
22503 privileged operations in a structured way. By querying the Polkit service, a
22504 privileged system component can know when it should grant additional
22505 capabilities to ordinary users. For example, an ordinary user can be granted
22506 the capability to suspend the system if the user is logged in locally.
22509 @defvr {Scheme Variable} polkit-wheel-service
22510 Service that adds the @code{wheel} group as admins to the Polkit
22511 service. This makes it so that users in the @code{wheel} group are queried
22512 for their own passwords when performing administrative actions instead of
22513 @code{root}'s, similar to the behaviour used by @code{sudo}.
22516 @defvr {Scheme Variable} upower-service-type
22517 Service that runs @uref{https://upower.freedesktop.org/, @command{upowerd}}, a
22518 system-wide monitor for power consumption and battery levels, with the given
22519 configuration settings.
22521 It implements the @code{org.freedesktop.UPower} D-Bus interface, and is
22522 notably used by GNOME.
22525 @deftp {Data Type} upower-configuration
22526 Data type representation the configuration for UPower.
22530 @item @code{upower} (default: @var{upower})
22531 Package to use for @code{upower}.
22533 @item @code{watts-up-pro?} (default: @code{#f})
22534 Enable the Watts Up Pro device.
22536 @item @code{poll-batteries?} (default: @code{#t})
22537 Enable polling the kernel for battery level changes.
22539 @item @code{ignore-lid?} (default: @code{#f})
22540 Ignore the lid state, this can be useful if it's incorrect on a device.
22542 @item @code{use-percentage-for-policy?} (default: @code{#f})
22543 Whether battery percentage based policy should be used. The default is to use
22544 the time left, change to @code{#t} to use the percentage.
22546 @item @code{percentage-low} (default: @code{10})
22547 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22548 at which the battery is considered low.
22550 @item @code{percentage-critical} (default: @code{3})
22551 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22552 at which the battery is considered critical.
22554 @item @code{percentage-action} (default: @code{2})
22555 When @code{use-percentage-for-policy?} is @code{#t}, this sets the percentage
22556 at which action will be taken.
22558 @item @code{time-low} (default: @code{1200})
22559 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22560 seconds at which the battery is considered low.
22562 @item @code{time-critical} (default: @code{300})
22563 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22564 seconds at which the battery is considered critical.
22566 @item @code{time-action} (default: @code{120})
22567 When @code{use-time-for-policy?} is @code{#f}, this sets the time remaining in
22568 seconds at which action will be taken.
22570 @item @code{critical-power-action} (default: @code{'hybrid-sleep})
22571 The action taken when @code{percentage-action} or @code{time-action} is
22572 reached (depending on the configuration of @code{use-percentage-for-policy?}).
22574 Possible values are:
22584 @code{'hybrid-sleep}.
22590 @deffn {Scheme Procedure} udisks-service [#:udisks @var{udisks}]
22591 Return a service for @uref{https://udisks.freedesktop.org/docs/latest/,
22592 UDisks}, a @dfn{disk management} daemon that provides user interfaces
22593 with notifications and ways to mount/unmount disks. Programs that talk
22594 to UDisks include the @command{udisksctl} command, part of UDisks, and
22595 GNOME Disks. Note that Udisks relies on the @command{mount} command, so
22596 it will only be able to use the file-system utilities installed in the
22597 system profile. For example if you want to be able to mount NTFS
22598 file-systems in read and write fashion, you'll need to have
22599 @code{ntfs-3g} installed system-wide.
22602 @deffn {Scheme Variable} colord-service-type
22603 This is the type of the service that runs @command{colord}, a system
22604 service with a D-Bus
22605 interface to manage the color profiles of input and output devices such as
22606 screens and scanners. It is notably used by the GNOME Color Manager graphical
22607 tool. See @uref{https://www.freedesktop.org/software/colord/, the colord web
22608 site} for more information.
22611 @cindex scanner access
22612 @defvr {Scheme Variable} sane-service-type
22613 This service provides access to scanners @i{via}
22614 @uref{http://www.sane-project.org, SANE} by installing the necessary
22615 udev rules. It is included in @code{%desktop-services} (@pxref{Desktop
22616 Services}) and relies by default on @code{sane-backends-minimal} package
22617 (see below) for hardware support.
22620 @defvr {Scheme Variable} sane-backends-minimal
22621 The default package which the @code{sane-service-type} installs. It
22622 supports many recent scanners.
22625 @defvr {Scheme Variable} sane-backends
22626 This package includes support for all scanners that
22627 @code{sane-backends-minimal} supports, plus older Hewlett-Packard
22628 scanners supported by @code{hplip} package. In order to use this on
22629 a system which relies on @code{%desktop-services}, you may use
22630 @code{modify-services} (@pxref{Service Reference,
22631 @code{modify-services}}) as illustrated below:
22634 (use-modules (gnu))
22635 (use-service-modules
22638 (use-package-modules
22642 (define %my-desktop-services
22643 ;; List of desktop services that supports a broader range of scanners.
22644 (modify-services %desktop-services
22645 (sane-service-type _ => sane-backends)))
22649 (services %my-desktop-services))
22653 @deffn {Scheme Procedure} geoclue-application name [#:allowed? #t] [#:system? #f] [#:users '()]
22654 Return a configuration allowing an application to access GeoClue
22655 location data. @var{name} is the Desktop ID of the application, without
22656 the @code{.desktop} part. If @var{allowed?} is true, the application
22657 will have access to location information by default. The boolean
22658 @var{system?} value indicates whether an application is a system component
22659 or not. Finally @var{users} is a list of UIDs of all users for which
22660 this application is allowed location info access. An empty users list
22661 means that all users are allowed.
22664 @defvr {Scheme Variable} %standard-geoclue-applications
22665 The standard list of well-known GeoClue application configurations,
22666 granting authority to the GNOME date-and-time utility to ask for the
22667 current location in order to set the time zone, and allowing the
22668 IceCat and Epiphany web browsers to request location information.
22669 IceCat and Epiphany both query the user before allowing a web page to
22670 know the user's location.
22673 @deffn {Scheme Procedure} geoclue-service [#:colord @var{colord}] @
22674 [#:whitelist '()] @
22675 [#:wifi-geolocation-url "https://location.services.mozilla.com/v1/geolocate?key=geoclue"] @
22676 [#:submit-data? #f]
22677 [#:wifi-submission-url "https://location.services.mozilla.com/v1/submit?key=geoclue"] @
22678 [#:submission-nick "geoclue"] @
22679 [#:applications %standard-geoclue-applications]
22680 Return a service that runs the GeoClue location service. This service
22681 provides a D-Bus interface to allow applications to request access to a
22682 user's physical location, and optionally to add information to online
22683 location databases. See
22684 @uref{https://wiki.freedesktop.org/www/Software/GeoClue/, the GeoClue
22685 web site} for more information.
22688 @deffn {Scheme Procedure} bluetooth-service [#:bluez @var{bluez}] @
22689 [@w{#:auto-enable? #f}]
22690 Return a service that runs the @command{bluetoothd} daemon, which
22691 manages all the Bluetooth devices and provides a number of D-Bus
22692 interfaces. When AUTO-ENABLE? is true, the bluetooth controller is
22693 powered automatically at boot, which can be useful when using a
22694 bluetooth keyboard or mouse.
22696 Users need to be in the @code{lp} group to access the D-Bus service.
22699 @deffn {Scheme Variable} bluetooth-service-type
22700 This is the type for the @uref{https://bluez.org/, Linux Bluetooth Protocol
22701 Stack} (BlueZ) system, which generates the @file{/etc/bluetooth/main.conf}
22702 configuration file. The value for this type is a @command{bluetooth-configuration}
22703 record as in this example:
22706 (service bluetooth-service-type)
22709 See below for details about @code{bluetooth-configuration}.
22712 @deftp {Data Type} bluetooth-configuration
22713 Data type representing the configuration for @code{bluetooth-service}.
22716 @item @code{bluez} (default: @code{bluez})
22717 @code{bluez} package to use.
22719 @item @code{name} (default: @code{"BlueZ"})
22720 Default adapter name.
22722 @item @code{class} (default: @code{#x000000})
22723 Default device class. Only the major and minor device class bits are considered.
22725 @item @code{discoverable-timeout} (default: @code{180})
22726 How long to stay in discoverable mode before going back to non-discoverable. The
22727 value is in seconds.
22729 @item @code{always-pairable?} (default: @code{#f})
22730 Always allow pairing even if there are no agents registered.
22732 @item @code{pairable-timeout} (default: @code{0})
22733 How long to stay in pairable mode before going back to non-discoverable. The
22734 value is in seconds.
22736 @item @code{device-id} (default: @code{#f})
22737 Use vendor id source (assigner), vendor, product and version information for
22738 DID profile support. The values are separated by ":" and @var{assigner}, @var{VID},
22739 @var{PID} and @var{version}.
22741 Possible values are:
22745 @code{#f} to disable it,
22748 @code{"assigner:1234:5678:abcd"}, where @var{assigner} is either @code{usb} (default)
22749 or @code{bluetooth}.
22753 @item @code{reverse-service-discovery?} (default: @code{#t})
22754 Do reverse service discovery for previously unknown devices that connect to
22755 us. For BR/EDR this option is really only needed for qualification since the
22756 BITE tester doesn't like us doing reverse SDP for some test cases, for LE
22757 this disables the GATT client functionally so it can be used in system which
22758 can only operate as peripheral.
22760 @item @code{name-resolving?} (default: @code{#t})
22761 Enable name resolving after inquiry. Set it to @code{#f} if you don't need
22762 remote devices name and want shorter discovery cycle.
22764 @item @code{debug-keys?} (default: @code{#f})
22765 Enable runtime persistency of debug link keys. Default is false which makes
22766 debug link keys valid only for the duration of the connection that they were
22769 @item @code{controller-mode} (default: @code{'dual})
22770 Restricts all controllers to the specified transport. @code{'dual} means both
22771 BR/EDR and LE are enabled (if supported by the hardware).
22773 Possible values are:
22787 @item @code{multi-profile} (default: @code{'off})
22788 Enables Multi Profile Specification support. This allows to specify if system
22789 supports only Multiple Profiles Single Device (MPSD) configuration or both
22790 Multiple Profiles Single Device (MPSD) and Multiple Profiles Multiple Devices
22791 (MPMD) configurations.
22793 Possible values are:
22807 @item @code{fast-connectable?} (default: @code{#f})
22808 Permanently enables the Fast Connectable setting for adapters that support
22809 it. When enabled other devices can connect faster to us, however the
22810 tradeoff is increased power consumptions. This feature will fully work only
22811 on kernel version 4.1 and newer.
22813 @item @code{privacy} (default: @code{'off})
22814 Default privacy settings.
22818 @code{'off}: Disable local privacy
22821 @code{'network/on}: A device will only accept advertising packets from peer
22822 devices that contain private addresses. It may not be compatible with some
22823 legacy devices since it requires the use of RPA(s) all the time
22826 @code{'device}: A device in device privacy mode is only concerned about the
22827 privacy of the device and will accept advertising packets from peer devices
22828 that contain their Identity Address as well as ones that contain a private
22829 address, even if the peer device has distributed its IRK in the past
22833 and additionally, if @var{controller-mode} is set to @code{'dual}:
22837 @code{'limited-network}: Apply Limited Discoverable Mode to advertising, which
22838 follows the same policy as to BR/EDR that publishes the identity address when
22839 discoverable, and Network Privacy Mode for scanning
22842 @code{'limited-device}: Apply Limited Discoverable Mode to advertising, which
22843 follows the same policy as to BR/EDR that publishes the identity address when
22844 discoverable, and Device Privacy Mode for scanning.
22848 @item @code{just-works-repairing} (default: @code{'never})
22849 Specify the policy to the JUST-WORKS repairing initiated by peer.
22864 @item @code{temporary-timeout} (default: @code{30})
22865 How long to keep temporary devices around. The value is in seconds. @code{0}
22866 disables the timer completely.
22868 @item @code{refresh-discovery?} (default: @code{#t})
22869 Enables the device to issue an SDP request to update known services when
22870 profile is connected.
22872 @item @code{experimental} (default: @code{#f})
22873 Enables experimental features and interfaces, alternatively a list of UUIDs
22886 @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
22889 List of possible UUIDs:
22892 @code{d4992530-b9ec-469f-ab01-6c481c47da1c}: BlueZ Experimental Debug,
22895 @code{671b10b5-42c0-4696-9227-eb28d1b049d6}: BlueZ Experimental Simultaneous Central and Peripheral,
22898 @code{"15c0a148-c273-11ea-b3de-0242ac130004}: BlueZ Experimental LL privacy,
22901 @code{330859bc-7506-492d-9370-9a6f0614037f}: BlueZ Experimental Bluetooth Quality Report,
22904 @code{a6695ace-ee7f-4fb9-881a-5fac66c629af}: BlueZ Experimental Offload Codecs.
22907 @item @code{remote-name-request-retry-delay} (default: @code{300})
22908 The duration to avoid retrying to resolve a peer's name, if the previous
22911 @item @code{page-scan-type} (default: @code{#f})
22912 BR/EDR Page scan activity type.
22914 @item @code{page-scan-interval} (default: @code{#f})
22915 BR/EDR Page scan activity interval.
22917 @item @code{page-scan-window} (default: @code{#f})
22918 BR/EDR Page scan activity window.
22920 @item @code{inquiry-scan-type} (default: @code{#f})
22921 BR/EDR Inquiry scan activity type.
22923 @item @code{inquiry-scan-interval} (default: @code{#f})
22924 BR/EDR Inquiry scan activity interval.
22926 @item @code{inquiry-scan-window} (default: @code{#f})
22927 BR/EDR Inquiry scan activity window.
22929 @item @code{link-supervision-timeout} (default: @code{#f})
22930 BR/EDR Link supervision timeout.
22932 @item @code{page-timeout} (default: @code{#f})
22933 BR/EDR Page timeout.
22935 @item @code{min-sniff-interval} (default: @code{#f})
22936 BR/EDR minimum sniff interval.
22938 @item @code{max-sniff-interval} (default: @code{#f})
22939 BR/EDR maximum sniff interval.
22941 @item @code{min-advertisement-interval} (default: @code{#f})
22942 LE minimum advertisement interval (used for legacy advertisement only).
22944 @item @code{max-advertisement-interval} (default: @code{#f})
22945 LE maximum advertisement interval (used for legacy advertisement only).
22947 @item @code{multi-advertisement-rotation-interval} (default: @code{#f})
22948 LE multiple advertisement rotation interval.
22950 @item @code{scan-interval-auto-connect} (default: @code{#f})
22951 LE scanning interval used for passive scanning supporting auto connect.
22953 @item @code{scan-window-auto-connect} (default: @code{#f})
22954 LE scanning window used for passive scanning supporting auto connect.
22956 @item @code{scan-interval-suspend} (default: @code{#f})
22957 LE scanning interval used for active scanning supporting wake from suspend.
22959 @item @code{scan-window-suspend} (default: @code{#f})
22960 LE scanning window used for active scanning supporting wake from suspend.
22962 @item @code{scan-interval-discovery} (default: @code{#f})
22963 LE scanning interval used for active scanning supporting discovery.
22965 @item @code{scan-window-discovery} (default: @code{#f})
22966 LE scanning window used for active scanning supporting discovery.
22968 @item @code{scan-interval-adv-monitor} (default: @code{#f})
22969 LE scanning interval used for passive scanning supporting the advertisement monitor APIs.
22971 @item @code{scan-window-adv-monitor} (default: @code{#f})
22972 LE scanning window used for passive scanning supporting the advertisement monitor APIs.
22974 @item @code{scan-interval-connect} (default: @code{#f})
22975 LE scanning interval used for connection establishment.
22977 @item @code{scan-window-connect} (default: @code{#f})
22978 LE scanning window used for connection establishment.
22980 @item @code{min-connection-interval} (default: @code{#f})
22981 LE default minimum connection interval. This value is superseded by any specific
22982 value provided via the Load Connection Parameters interface.
22984 @item @code{max-connection-interval} (default: @code{#f})
22985 LE default maximum connection interval. This value is superseded by any specific
22986 value provided via the Load Connection Parameters interface.
22988 @item @code{connection-latency} (default: @code{#f})
22989 LE default connection latency. This value is superseded by any specific
22990 value provided via the Load Connection Parameters interface.
22992 @item @code{connection-supervision-timeout} (default: @code{#f})
22993 LE default connection supervision timeout. This value is superseded by any specific
22994 value provided via the Load Connection Parameters interface.
22996 @item @code{autoconnect-timeout} (default: @code{#f})
22997 LE default autoconnect timeout. This value is superseded by any specific
22998 value provided via the Load Connection Parameters interface.
23000 @item @code{adv-mon-allowlist-scan-duration} (default: @code{300})
23001 Allowlist scan duration during interleaving scan. Only used when scanning for ADV
23002 monitors. The units are msec.
23004 @item @code{adv-mon-no-filter-scan-duration} (default: @code{500})
23005 No filter scan duration during interleaving scan. Only used when scanning for ADV
23006 monitors. The units are msec.
23008 @item @code{enable-adv-mon-interleave-scan?} (default: @code{#t})
23009 Enable/Disable Advertisement Monitor interleave scan for power saving.
23011 @item @code{cache} (default: @code{'always})
23012 GATT attribute cache.
23014 Possible values are:
23017 @code{'always}: Always cache attributes even for devices not paired, this is
23018 recommended as it is best for interoperability, with more consistent
23019 reconnection times and enables proper tracking of notifications for all
23023 @code{'yes}: Only cache attributes of paired devices
23026 @code{'no}: Never cache attributes.
23029 @item @code{key-size} (default: @code{0})
23030 Minimum required Encryption Key Size for accessing secured characteristics.
23032 Possible values are:
23035 @code{0}: Don't care
23038 @code{7 <= N <= 16}
23041 @item @code{exchange-mtu} (default: @code{517})
23042 Exchange MTU size. Possible values are:
23046 @code{23 <= N <= 517}
23049 @item @code{att-channels} (default: @code{3})
23050 Number of ATT channels. Possible values are:
23054 @code{1}: Disables EATT
23060 @item @code{session-mode} (default: @code{'basic})
23061 AVDTP L2CAP signalling channel mode.
23063 Possible values are:
23067 @code{'basic}: Use L2CAP basic mode
23070 @code{'ertm}: Use L2CAP enhanced retransmission mode.
23073 @item @code{stream-mode} (default: @code{'basic})
23074 AVDTP L2CAP transport channel mode.
23076 Possible values are:
23080 @code{'basic}: Use L2CAP basic mode
23083 @code{'streaming}: Use L2CAP streaming mode.
23086 @item @code{reconnect-uuids} (default: @code{'()})
23087 The ReconnectUUIDs defines the set of remote services that should try
23088 to be reconnected to in case of a link loss (link supervision
23089 timeout). The policy plugin should contain a sane set of values by
23090 default, but this list can be overridden here. By setting the list to
23091 empty the reconnection feature gets disabled.
23100 @code{(list (uuid <uuid-1>) (uuid <uuid-2>) ...)}.
23103 @item @code{reconnect-attempts} (default: @code{7})
23104 Defines the number of attempts to reconnect after a link lost. Setting
23105 the value to 0 disables reconnecting feature.
23107 @item @code{reconnect-intervals} (default: @code{'(1 2 4 8 16 32 64)})
23108 Defines a list of intervals in seconds to use in between attempts. If
23109 the number of attempts defined in @var{reconnect-attempts} is bigger than
23110 the list of intervals the last interval is repeated until the last attempt.
23112 @item @code{auto-enable?} (default: @code{#f})
23113 Defines option to enable all controllers when they are found. This includes
23114 adapters present on start as well as adapters that are plugged in later on.
23116 @item @code{resume-delay} (default: @code{2})
23117 Audio devices that were disconnected due to suspend will be reconnected on
23118 resume. @var{resume-delay} determines the delay between when the controller
23119 resumes from suspend and a connection attempt is made. A longer delay is
23120 better for better co-existence with Wi-Fi. The value is in seconds.
23122 @item @code{rssi-sampling-period} (default: @code{#xFF})
23123 Default RSSI Sampling Period. This is used when a client registers an
23124 advertisement monitor and leaves the RSSISamplingPeriod unset.
23126 Possible values are:
23129 @code{#x0}: Report all advertisements
23132 @code{N = #xXX}: Report advertisements every N x 100 msec (range: #x01 to #xFE)
23135 @code{#xFF}: Report only one advertisement per device during monitoring period.
23141 @defvr {Scheme Variable} gnome-keyring-service-type
23142 This is the type of the service that adds the
23143 @uref{https://wiki.gnome.org/Projects/GnomeKeyring, GNOME Keyring}. Its
23144 value is a @code{gnome-keyring-configuration} object (see below).
23146 This service adds the @code{gnome-keyring} package to the system profile
23147 and extends PAM with entries using @code{pam_gnome_keyring.so}, unlocking
23148 a user's login keyring when they log in or setting its password with passwd.
23151 @deftp {Data Type} gnome-keyring-configuration
23152 Configuration record for the GNOME Keyring service.
23155 @item @code{keyring} (default: @code{gnome-keyring})
23156 The GNOME keyring package to use.
23158 @item @code{pam-services}
23159 A list of @code{(@var{service} . @var{kind})} pairs denoting PAM
23160 services to extend, where @var{service} is the name of an existing
23161 service to extend and @var{kind} is one of @code{login} or
23164 If @code{login} is given, it adds an optional
23165 @code{pam_gnome_keyring.so} to the auth block without arguments and to
23166 the session block with @code{auto_start}. If @code{passwd} is given, it
23167 adds an optional @code{pam_gnome_keyring.so} to the password block
23170 By default, this field contains ``gdm-password'' with the value @code{login}
23171 and ``passwd'' is with the value @code{passwd}.
23175 @defvr {Scheme Variable} seatd-service-type
23176 @uref{https://sr.ht/~kennylevinsen/seatd/, seatd} is a minimal seat
23179 Seat management takes care of mediating access to shared devices (graphics,
23180 input), without requiring the applications needing access to be root.
23185 ;; make sure seatd is running
23186 (service seatd-service-type))
23188 ;; normally one would want %base-services
23194 @deftp {Data Type} seatd-configuration
23195 Configuration record for the seatd daemon service.
23198 @item @code{seatd} (default: @code{seatd})
23199 The seatd package to use.
23201 @item @code{user} (default: @samp{"root"})
23202 User to own the seatd socket.
23204 @item @code{group} (default: @samp{"users"})
23205 Group to own the seatd socket.
23207 @item @code{socket} (default: @samp{"/run/seatd.sock"})
23208 Where to create the seatd socket.
23210 @item @code{logfile} (default: @samp{"/var/log/seatd.log"})
23211 Log file to write to.
23213 @item @code{loglevel} (default: @samp{"error"})
23214 Log level to output logs. Possible values: @samp{"silent"}, @samp{"error"},
23215 @samp{"info"} and @samp{"debug"}.
23221 @node Sound Services
23222 @subsection Sound Services
23224 @cindex sound support
23226 @cindex PulseAudio, sound support
23228 The @code{(gnu services sound)} module provides a service to configure the
23229 Advanced Linux Sound Architecture (ALSA) system, which makes PulseAudio the
23230 preferred ALSA output driver.
23232 @deffn {Scheme Variable} alsa-service-type
23233 This is the type for the @uref{https://alsa-project.org/, Advanced Linux Sound
23234 Architecture} (ALSA) system, which generates the @file{/etc/asound.conf}
23235 configuration file. The value for this type is a @command{alsa-configuration}
23236 record as in this example:
23239 (service alsa-service-type)
23242 See below for details about @code{alsa-configuration}.
23245 @deftp {Data Type} alsa-configuration
23246 Data type representing the configuration for @code{alsa-service}.
23249 @item @code{alsa-plugins} (default: @var{alsa-plugins})
23250 @code{alsa-plugins} package to use.
23252 @item @code{pulseaudio?} (default: @var{#t})
23253 Whether ALSA applications should transparently be made to use the
23254 @uref{https://www.pulseaudio.org/, PulseAudio} sound server.
23256 Using PulseAudio allows you to run several sound-producing applications
23257 at the same time and to individual control them @i{via}
23258 @command{pavucontrol}, among other things.
23260 @item @code{extra-options} (default: @var{""})
23261 String to append to the @file{/etc/asound.conf} file.
23266 Individual users who want to override the system configuration of ALSA can do
23267 it with the @file{~/.asoundrc} file:
23270 # In guix, we have to specify the absolute path for plugins.
23272 lib "/home/alice/.guix-profile/lib/alsa-lib/libasound_module_pcm_jack.so"
23275 # Routing ALSA to jack:
23276 # <http://jackaudio.org/faq/routing_alsa.html>.
23280 0 system:playback_1
23281 1 system:playback_2
23298 See @uref{https://www.alsa-project.org/main/index.php/Asoundrc} for the
23301 @deffn {Scheme Variable} pulseaudio-service-type
23302 This is the type for the @uref{https://www.pulseaudio.org/, PulseAudio}
23303 sound server. It exists to allow system overrides of the default settings
23304 via @code{pulseaudio-configuration}, see below.
23307 This service overrides per-user configuration files. If you want
23308 PulseAudio to honor configuration files in @file{~/.config/pulse} you
23309 have to unset the environment variables @env{PULSE_CONFIG} and
23310 @env{PULSE_CLIENTCONFIG} in your @file{~/.bash_profile}.
23314 This service on its own does not ensure, that the @code{pulseaudio} package
23315 exists on your machine. It merely adds configuration files for it, as
23316 detailed below. In the (admittedly unlikely) case, that you find yourself
23317 without a @code{pulseaudio} package, consider enabling it through the
23318 @code{alsa-service-type} above.
23322 @deftp {Data Type} pulseaudio-configuration
23323 Data type representing the configuration for @code{pulseaudio-service}.
23326 @item @code{client-conf} (default: @code{'()})
23327 List of settings to set in @file{client.conf}.
23328 Accepts a list of strings or symbol-value pairs. A string will be
23329 inserted as-is with a newline added. A pair will be formatted as
23330 ``key = value'', again with a newline added.
23332 @item @code{daemon-conf} (default: @code{'((flat-volumes . no))})
23333 List of settings to set in @file{daemon.conf}, formatted just like
23336 @item @code{script-file} (default: @code{(file-append pulseaudio "/etc/pulse/default.pa")})
23337 Script file to use as @file{default.pa}. In case the
23338 @code{extra-script-files} field below is used, an @code{.include}
23339 directive pointing to @file{/etc/pulse/default.pa.d} is appended to the
23342 @item @code{extra-script-files} (default: @code{'())})
23343 A list of file-like objects defining extra PulseAudio scripts to run at
23344 the initialization of the @command{pulseaudio} daemon, after the main
23345 @code{script-file}. The scripts are deployed to the
23346 @file{/etc/pulse/default.pa.d} directory; they should have the
23347 @samp{.pa} file name extension. For a reference of the available
23348 commands, refer to @command{man pulse-cli-syntax}.
23350 @item @code{system-script-file} (default: @code{(file-append pulseaudio "/etc/pulse/system.pa")})
23351 Script file to use as @file{system.pa}.
23354 The example below sets the default PulseAudio card profile, the default
23355 sink and the default source to use for a old SoundBlaster Audigy sound
23358 (pulseaudio-configuration
23359 (extra-script-files
23360 (list (plain-file "audigy.pa"
23362 set-card-profile alsa_card.pci-0000_01_01.0 \
23363 output:analog-surround-40+input:analog-mono
23364 set-default-source alsa_input.pci-0000_01_01.0.analog-mono
23365 set-default-sink alsa_output.pci-0000_01_01.0.analog-surround-40\n")))))
23368 Note that @code{pulseaudio-service-type} is part of
23369 @code{%desktop-services}; if your operating system declaration was
23370 derived from one of the desktop templates, you'll want to adjust the
23371 above example to modify the existing @code{pulseaudio-service-type} via
23372 @code{modify-services} (@pxref{Service Reference,
23373 @code{modify-services}}), instead of defining a new one.
23377 @deffn {Scheme Variable} ladspa-service-type
23378 This service sets the @var{LADSPA_PATH} variable, so that programs, which
23379 respect it, e.g. PulseAudio, can load LADSPA plugins.
23381 The following example will setup the service to enable modules from the
23382 @code{swh-plugins} package:
23385 (service ladspa-service-type
23386 (ladspa-configuration (plugins (list swh-plugins))))
23389 See @uref{http://plugin.org.uk/ladspa-swh/docs/ladspa-swh.html} for the
23394 @node Database Services
23395 @subsection Database Services
23399 The @code{(gnu services databases)} module provides the following services.
23401 @subsubheading PostgreSQL
23403 The following example describes a PostgreSQL service with the default
23407 (service postgresql-service-type
23408 (postgresql-configuration
23409 (postgresql postgresql-10)))
23412 If the services fails to start, it may be due to an incompatible
23413 cluster already present in @var{data-directory}. Adjust it (or, if you
23414 don't need the cluster anymore, delete @var{data-directory}), then
23415 restart the service.
23417 Peer authentication is used by default and the @code{postgres} user
23418 account has no shell, which prevents the direct execution of @code{psql}
23419 commands as this user. To use @code{psql}, you can temporarily log in
23420 as @code{postgres} using a shell, create a PostgreSQL superuser with the
23421 same name as one of the system users and then create the associated
23425 sudo -u postgres -s /bin/sh
23426 createuser --interactive
23427 createdb $MY_USER_LOGIN # Replace appropriately.
23430 @deftp {Data Type} postgresql-configuration
23431 Data type representing the configuration for the
23432 @code{postgresql-service-type}.
23435 @item @code{postgresql}
23436 PostgreSQL package to use for the service.
23438 @item @code{port} (default: @code{5432})
23439 Port on which PostgreSQL should listen.
23441 @item @code{locale} (default: @code{"en_US.utf8"})
23442 Locale to use as the default when creating the database cluster.
23444 @item @code{config-file} (default: @code{(postgresql-config-file)})
23445 The configuration file to use when running PostgreSQL@. The default
23446 behaviour uses the postgresql-config-file record with the default values
23449 @item @code{log-directory} (default: @code{"/var/log/postgresql"})
23450 The directory where @command{pg_ctl} output will be written in a file
23451 named @code{"pg_ctl.log"}. This file can be useful to debug PostgreSQL
23452 configuration errors for instance.
23454 @item @code{data-directory} (default: @code{"/var/lib/postgresql/data"})
23455 Directory in which to store the data.
23457 @item @code{extension-packages} (default: @code{'()})
23458 @cindex postgresql extension-packages
23459 Additional extensions are loaded from packages listed in
23460 @var{extension-packages}. Extensions are available at runtime. For instance,
23461 to create a geographic database using the @code{postgis} extension, a user can
23462 configure the postgresql-service as in this example:
23466 (use-package-modules databases geo)
23470 ;; postgresql is required to run `psql' but postgis is not required for
23471 ;; proper operation.
23472 (packages (cons* postgresql %base-packages))
23475 (service postgresql-service-type
23476 (postgresql-configuration
23477 (postgresql postgresql-10)
23478 (extension-packages (list postgis))))
23482 Then the extension becomes visible and you can initialise an empty geographic
23483 database in this way:
23487 > create database postgistest;
23488 > \connect postgistest;
23489 > create extension postgis;
23490 > create extension postgis_topology;
23493 There is no need to add this field for contrib extensions such as hstore or
23494 dblink as they are already loadable by postgresql. This field is only
23495 required to add extensions provided by other packages.
23500 @deftp {Data Type} postgresql-config-file
23501 Data type representing the PostgreSQL configuration file. As shown in
23502 the following example, this can be used to customize the configuration
23503 of PostgreSQL@. Note that you can use any G-expression or filename in
23504 place of this record, if you already have a configuration file you'd
23505 like to use for example.
23508 (service postgresql-service-type
23509 (postgresql-configuration
23511 (postgresql-config-file
23512 (log-destination "stderr")
23514 (plain-file "pg_hba.conf"
23516 local all all trust
23517 host all all 127.0.0.1/32 md5
23518 host all all ::1/128 md5"))
23520 '(("session_preload_libraries" "auto_explain")
23521 ("random_page_cost" 2)
23522 ("auto_explain.log_min_duration" "100 ms")
23523 ("work_mem" "500 MB")
23524 ("logging_collector" #t)
23525 ("log_directory" "/var/log/postgresql")))))))
23529 @item @code{log-destination} (default: @code{"syslog"})
23530 The logging method to use for PostgreSQL@. Multiple values are accepted,
23531 separated by commas.
23533 @item @code{hba-file} (default: @code{%default-postgres-hba})
23534 Filename or G-expression for the host-based authentication
23537 @item @code{ident-file} (default: @code{%default-postgres-ident})
23538 Filename or G-expression for the user name mapping configuration.
23540 @item @code{socket-directory} (default: @code{"/var/run/postgresql"})
23541 Specifies the directory of the Unix-domain socket(s) on which PostgreSQL
23542 is to listen for connections from client applications. If set to
23543 @code{""} PostgreSQL does not listen on any Unix-domain sockets, in
23544 which case only TCP/IP sockets can be used to connect to the server.
23546 By default, the @code{#false} value means the PostgreSQL default value
23547 will be used, which is currently @samp{/tmp}.
23549 @item @code{extra-config} (default: @code{'()})
23550 List of additional keys and values to include in the PostgreSQL config
23551 file. Each entry in the list should be a list where the first element
23552 is the key, and the remaining elements are the values.
23554 The values can be numbers, booleans or strings and will be mapped to
23555 PostgreSQL parameters types @code{Boolean}, @code{String},
23556 @code{Numeric}, @code{Numeric with Unit} and @code{Enumerated} described
23557 @uref{https://www.postgresql.org/docs/current/config-setting.html,
23563 @deffn {Scheme Variable} postgresql-role-service-type
23564 This service allows to create PostgreSQL roles and databases after
23565 PostgreSQL service start. Here is an example of its use.
23568 (service postgresql-role-service-type
23569 (postgresql-role-configuration
23571 (list (postgresql-role
23573 (create-database? #t))))))
23576 This service can be extended with extra roles, as in this
23580 (service-extension postgresql-role-service-type
23581 (const (postgresql-role
23583 (create-database? #t))))
23587 @deftp {Data Type} postgresql-role
23588 PostgreSQL manages database access permissions using the concept of
23589 roles. A role can be thought of as either a database user, or a group
23590 of database users, depending on how the role is set up. Roles can own
23591 database objects (for example, tables) and can assign privileges on
23592 those objects to other roles to control who has access to which objects.
23598 @item @code{permissions} (default: @code{'(createdb login)})
23599 The role permissions list. Supported permissions are @code{bypassrls},
23600 @code{createdb}, @code{createrole}, @code{login}, @code{replication} and
23603 @item @code{create-database?} (default: @code{#f})
23604 Whether to create a database with the same name as the role.
23609 @deftp {Data Type} postgresql-role-configuration
23610 Data type representing the configuration of
23611 @var{postgresql-role-service-type}.
23614 @item @code{host} (default: @code{"/var/run/postgresql"})
23615 The PostgreSQL host to connect to.
23617 @item @code{log} (default: @code{"/var/log/postgresql_roles.log"})
23618 File name of the log file.
23620 @item @code{roles} (default: @code{'()})
23621 The initial PostgreSQL roles to create.
23625 @subsubheading MariaDB/MySQL
23627 @defvr {Scheme Variable} mysql-service-type
23628 This is the service type for a MySQL or MariaDB database server. Its value
23629 is a @code{mysql-configuration} object that specifies which package to use,
23630 as well as various settings for the @command{mysqld} daemon.
23633 @deftp {Data Type} mysql-configuration
23634 Data type representing the configuration of @var{mysql-service-type}.
23637 @item @code{mysql} (default: @var{mariadb})
23638 Package object of the MySQL database server, can be either @var{mariadb}
23641 For MySQL, a temporary root password will be displayed at activation time.
23642 For MariaDB, the root password is empty.
23644 @item @code{bind-address} (default: @code{"127.0.0.1"})
23645 The IP on which to listen for network connections. Use @code{"0.0.0.0"}
23646 to bind to all available network interfaces.
23648 @item @code{port} (default: @code{3306})
23649 TCP port on which the database server listens for incoming connections.
23651 @item @code{socket} (default: @code{"/run/mysqld/mysqld.sock"})
23652 Socket file to use for local (non-network) connections.
23654 @item @code{extra-content} (default: @code{""})
23655 Additional settings for the @file{my.cnf} configuration file.
23657 @item @code{extra-environment} (default: @code{#~'()})
23658 List of environment variables passed to the @command{mysqld} process.
23660 @item @code{auto-upgrade?} (default: @code{#t})
23661 Whether to automatically run @command{mysql_upgrade} after starting the
23662 service. This is necessary to upgrade the @dfn{system schema} after
23663 ``major'' updates (such as switching from MariaDB 10.4 to 10.5), but can
23664 be disabled if you would rather do that manually.
23669 @subsubheading Memcached
23671 @defvr {Scheme Variable} memcached-service-type
23672 This is the service type for the @uref{https://memcached.org/,
23673 Memcached} service, which provides a distributed in memory cache. The
23674 value for the service type is a @code{memcached-configuration} object.
23678 (service memcached-service-type)
23681 @deftp {Data Type} memcached-configuration
23682 Data type representing the configuration of memcached.
23685 @item @code{memcached} (default: @code{memcached})
23686 The Memcached package to use.
23688 @item @code{interfaces} (default: @code{'("0.0.0.0")})
23689 Network interfaces on which to listen.
23691 @item @code{tcp-port} (default: @code{11211})
23692 Port on which to accept connections.
23694 @item @code{udp-port} (default: @code{11211})
23695 Port on which to accept UDP connections on, a value of 0 will disable
23696 listening on a UDP socket.
23698 @item @code{additional-options} (default: @code{'()})
23699 Additional command line options to pass to @code{memcached}.
23703 @subsubheading Redis
23705 @defvr {Scheme Variable} redis-service-type
23706 This is the service type for the @uref{https://redis.io/, Redis}
23707 key/value store, whose value is a @code{redis-configuration} object.
23710 @deftp {Data Type} redis-configuration
23711 Data type representing the configuration of redis.
23714 @item @code{redis} (default: @code{redis})
23715 The Redis package to use.
23717 @item @code{bind} (default: @code{"127.0.0.1"})
23718 Network interface on which to listen.
23720 @item @code{port} (default: @code{6379})
23721 Port on which to accept connections on, a value of 0 will disable
23722 listening on a TCP socket.
23724 @item @code{working-directory} (default: @code{"/var/lib/redis"})
23725 Directory in which to store the database and related files.
23729 @node Mail Services
23730 @subsection Mail Services
23734 The @code{(gnu services mail)} module provides Guix service definitions
23735 for email services: IMAP, POP3, and LMTP servers, as well as mail
23736 transport agents (MTAs). Lots of acronyms! These services are detailed
23737 in the subsections below.
23739 @subsubheading Dovecot Service
23741 @deffn {Scheme Procedure} dovecot-service [#:config (dovecot-configuration)]
23742 Return a service that runs the Dovecot IMAP/POP3/LMTP mail server.
23745 By default, Dovecot does not need much configuration; the default
23746 configuration object created by @code{(dovecot-configuration)} will
23747 suffice if your mail is delivered to @code{~/Maildir}. A self-signed
23748 certificate will be generated for TLS-protected connections, though
23749 Dovecot will also listen on cleartext ports by default. There are a
23750 number of options, though, which mail administrators might need to change,
23751 and as is the case with other services, Guix allows the system
23752 administrator to specify these parameters via a uniform Scheme interface.
23754 For example, to specify that mail is located at @code{maildir~/.mail},
23755 one would instantiate the Dovecot service like this:
23758 (dovecot-service #:config
23759 (dovecot-configuration
23760 (mail-location "maildir:~/.mail")))
23763 The available configuration parameters follow. Each parameter
23764 definition is preceded by its type; for example, @samp{string-list foo}
23765 indicates that the @code{foo} parameter should be specified as a list of
23766 strings. There is also a way to specify the configuration as a string,
23767 if you have an old @code{dovecot.conf} file that you want to port over
23768 from some other system; see the end for more details.
23770 @c The following documentation was initially generated by
23771 @c (generate-documentation) in (gnu services mail). Manually maintained
23772 @c documentation is better, so we shouldn't hesitate to edit below as
23773 @c needed. However if the change you want to make to this documentation
23774 @c can be done in an automated way, it's probably easier to change
23775 @c (generate-documentation) than to make it below and have to deal with
23776 @c the churn as dovecot updates.
23778 Available @code{dovecot-configuration} fields are:
23780 @deftypevr {@code{dovecot-configuration} parameter} package dovecot
23781 The dovecot package.
23784 @deftypevr {@code{dovecot-configuration} parameter} comma-separated-string-list listen
23785 A list of IPs or hosts where to listen for connections. @samp{*}
23786 listens on all IPv4 interfaces, @samp{::} listens on all IPv6
23787 interfaces. If you want to specify non-default ports or anything more
23788 complex, customize the address and port fields of the
23789 @samp{inet-listener} of the specific services you are interested in.
23792 @deftypevr {@code{dovecot-configuration} parameter} protocol-configuration-list protocols
23793 List of protocols we want to serve. Available protocols include
23794 @samp{imap}, @samp{pop3}, and @samp{lmtp}.
23796 Available @code{protocol-configuration} fields are:
23798 @deftypevr {@code{protocol-configuration} parameter} string name
23799 The name of the protocol.
23802 @deftypevr {@code{protocol-configuration} parameter} string auth-socket-path
23803 UNIX socket path to the master authentication server to find users.
23804 This is used by imap (for shared users) and lda.
23805 It defaults to @samp{"/var/run/dovecot/auth-userdb"}.
23808 @deftypevr {@code{protocol-configuration} parameter} boolean imap-metadata?
23809 Whether to enable the @code{IMAP METADATA} extension as defined in
23810 @uref{https://tools.ietf.org/html/rfc5464,RFC@tie{}5464}, which provides
23811 a means for clients to set and retrieve per-mailbox, per-user metadata
23812 and annotations over IMAP.
23814 If this is @samp{#t}, you must also specify a dictionary @i{via} the
23815 @code{mail-attribute-dict} setting.
23817 Defaults to @samp{#f}.
23821 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-notify-capabilities
23822 Which NOTIFY capabilities to report to clients that first connect to
23823 the ManageSieve service, before authentication. These may differ from the
23824 capabilities offered to authenticated users. If this field is left empty,
23825 report what the Sieve interpreter supports by default.
23827 Defaults to @samp{()}.
23830 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-sieve-capability
23831 Which SIEVE capabilities to report to clients that first connect to
23832 the ManageSieve service, before authentication. These may differ from the
23833 capabilities offered to authenticated users. If this field is left empty,
23834 report what the Sieve interpreter supports by default.
23836 Defaults to @samp{()}.
23840 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
23841 Space separated list of plugins to load.
23844 @deftypevr {@code{protocol-configuration} parameter} non-negative-integer mail-max-userip-connections
23845 Maximum number of IMAP connections allowed for a user from each IP
23846 address. NOTE: The username is compared case-sensitively.
23847 Defaults to @samp{10}.
23852 @deftypevr {@code{dovecot-configuration} parameter} service-configuration-list services
23853 List of services to enable. Available services include @samp{imap},
23854 @samp{imap-login}, @samp{pop3}, @samp{pop3-login}, @samp{auth}, and
23857 Available @code{service-configuration} fields are:
23859 @deftypevr {@code{service-configuration} parameter} string kind
23860 The service kind. Valid values include @code{director},
23861 @code{imap-login}, @code{pop3-login}, @code{lmtp}, @code{imap},
23862 @code{pop3}, @code{auth}, @code{auth-worker}, @code{dict},
23863 @code{tcpwrap}, @code{quota-warning}, or anything else.
23866 @deftypevr {@code{service-configuration} parameter} listener-configuration-list listeners
23867 Listeners for the service. A listener is either a
23868 @code{unix-listener-configuration}, a @code{fifo-listener-configuration}, or
23869 an @code{inet-listener-configuration}.
23870 Defaults to @samp{()}.
23872 Available @code{unix-listener-configuration} fields are:
23874 @deftypevr {@code{unix-listener-configuration} parameter} string path
23875 Path to the file, relative to @code{base-dir} field. This is also used as
23879 @deftypevr {@code{unix-listener-configuration} parameter} string mode
23880 The access mode for the socket.
23881 Defaults to @samp{"0600"}.
23884 @deftypevr {@code{unix-listener-configuration} parameter} string user
23885 The user to own the socket.
23886 Defaults to @samp{""}.
23889 @deftypevr {@code{unix-listener-configuration} parameter} string group
23890 The group to own the socket.
23891 Defaults to @samp{""}.
23895 Available @code{fifo-listener-configuration} fields are:
23897 @deftypevr {@code{fifo-listener-configuration} parameter} string path
23898 Path to the file, relative to @code{base-dir} field. This is also used as
23902 @deftypevr {@code{fifo-listener-configuration} parameter} string mode
23903 The access mode for the socket.
23904 Defaults to @samp{"0600"}.
23907 @deftypevr {@code{fifo-listener-configuration} parameter} string user
23908 The user to own the socket.
23909 Defaults to @samp{""}.
23912 @deftypevr {@code{fifo-listener-configuration} parameter} string group
23913 The group to own the socket.
23914 Defaults to @samp{""}.
23918 Available @code{inet-listener-configuration} fields are:
23920 @deftypevr {@code{inet-listener-configuration} parameter} string protocol
23921 The protocol to listen for.
23924 @deftypevr {@code{inet-listener-configuration} parameter} string address
23925 The address on which to listen, or empty for all addresses.
23926 Defaults to @samp{""}.
23929 @deftypevr {@code{inet-listener-configuration} parameter} non-negative-integer port
23930 The port on which to listen.
23933 @deftypevr {@code{inet-listener-configuration} parameter} boolean ssl?
23934 Whether to use SSL for this service; @samp{yes}, @samp{no}, or
23936 Defaults to @samp{#t}.
23941 @deftypevr {@code{service-configuration} parameter} non-negative-integer client-limit
23942 Maximum number of simultaneous client connections per process. Once
23943 this number of connections is received, the next incoming connection
23944 will prompt Dovecot to spawn another process. If set to 0,
23945 @code{default-client-limit} is used instead.
23947 Defaults to @samp{0}.
23951 @deftypevr {@code{service-configuration} parameter} non-negative-integer service-count
23952 Number of connections to handle before starting a new process.
23953 Typically the only useful values are 0 (unlimited) or 1. 1 is more
23954 secure, but 0 is faster. <doc/wiki/LoginProcess.txt>.
23955 Defaults to @samp{1}.
23959 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-limit
23960 Maximum number of processes that can exist for this service. If set to
23961 0, @code{default-process-limit} is used instead.
23963 Defaults to @samp{0}.
23967 @deftypevr {@code{service-configuration} parameter} non-negative-integer process-min-avail
23968 Number of processes to always keep waiting for more connections.
23969 Defaults to @samp{0}.
23972 @deftypevr {@code{service-configuration} parameter} non-negative-integer vsz-limit
23973 If you set @samp{service-count 0}, you probably need to grow
23975 Defaults to @samp{256000000}.
23980 @deftypevr {@code{dovecot-configuration} parameter} dict-configuration dict
23981 Dict configuration, as created by the @code{dict-configuration}
23984 Available @code{dict-configuration} fields are:
23986 @deftypevr {@code{dict-configuration} parameter} free-form-fields entries
23987 A list of key-value pairs that this dict should hold.
23988 Defaults to @samp{()}.
23993 @deftypevr {@code{dovecot-configuration} parameter} passdb-configuration-list passdbs
23994 A list of passdb configurations, each one created by the
23995 @code{passdb-configuration} constructor.
23997 Available @code{passdb-configuration} fields are:
23999 @deftypevr {@code{passdb-configuration} parameter} string driver
24000 The driver that the passdb should use. Valid values include
24001 @samp{pam}, @samp{passwd}, @samp{shadow}, @samp{bsdauth}, and
24003 Defaults to @samp{"pam"}.
24006 @deftypevr {@code{passdb-configuration} parameter} space-separated-string-list args
24007 Space separated list of arguments to the passdb driver.
24008 Defaults to @samp{""}.
24013 @deftypevr {@code{dovecot-configuration} parameter} userdb-configuration-list userdbs
24014 List of userdb configurations, each one created by the
24015 @code{userdb-configuration} constructor.
24017 Available @code{userdb-configuration} fields are:
24019 @deftypevr {@code{userdb-configuration} parameter} string driver
24020 The driver that the userdb should use. Valid values include
24021 @samp{passwd} and @samp{static}.
24022 Defaults to @samp{"passwd"}.
24025 @deftypevr {@code{userdb-configuration} parameter} space-separated-string-list args
24026 Space separated list of arguments to the userdb driver.
24027 Defaults to @samp{""}.
24030 @deftypevr {@code{userdb-configuration} parameter} free-form-args override-fields
24031 Override fields from passwd.
24032 Defaults to @samp{()}.
24037 @deftypevr {@code{dovecot-configuration} parameter} plugin-configuration plugin-configuration
24038 Plug-in configuration, created by the @code{plugin-configuration}
24042 @deftypevr {@code{dovecot-configuration} parameter} list-of-namespace-configuration namespaces
24043 List of namespaces. Each item in the list is created by the
24044 @code{namespace-configuration} constructor.
24046 Available @code{namespace-configuration} fields are:
24048 @deftypevr {@code{namespace-configuration} parameter} string name
24049 Name for this namespace.
24052 @deftypevr {@code{namespace-configuration} parameter} string type
24053 Namespace type: @samp{private}, @samp{shared} or @samp{public}.
24054 Defaults to @samp{"private"}.
24057 @deftypevr {@code{namespace-configuration} parameter} string separator
24058 Hierarchy separator to use. You should use the same separator for
24059 all namespaces or some clients get confused. @samp{/} is usually a good
24060 one. The default however depends on the underlying mail storage
24062 Defaults to @samp{""}.
24065 @deftypevr {@code{namespace-configuration} parameter} string prefix
24066 Prefix required to access this namespace. This needs to be
24067 different for all namespaces. For example @samp{Public/}.
24068 Defaults to @samp{""}.
24071 @deftypevr {@code{namespace-configuration} parameter} string location
24072 Physical location of the mailbox. This is in the same format as
24073 mail_location, which is also the default for it.
24074 Defaults to @samp{""}.
24077 @deftypevr {@code{namespace-configuration} parameter} boolean inbox?
24078 There can be only one INBOX, and this setting defines which
24080 Defaults to @samp{#f}.
24083 @deftypevr {@code{namespace-configuration} parameter} boolean hidden?
24084 If namespace is hidden, it's not advertised to clients via NAMESPACE
24085 extension. You'll most likely also want to set @samp{list? #f}. This is mostly
24086 useful when converting from another server with different namespaces
24087 which you want to deprecate but still keep working. For example you can
24088 create hidden namespaces with prefixes @samp{~/mail/}, @samp{~%u/mail/}
24090 Defaults to @samp{#f}.
24093 @deftypevr {@code{namespace-configuration} parameter} boolean list?
24094 Show the mailboxes under this namespace with the LIST command. This
24095 makes the namespace visible for clients that do not support the NAMESPACE
24096 extension. The special @code{children} value lists child mailboxes, but
24097 hides the namespace prefix.
24098 Defaults to @samp{#t}.
24101 @deftypevr {@code{namespace-configuration} parameter} boolean subscriptions?
24102 Namespace handles its own subscriptions. If set to @code{#f}, the
24103 parent namespace handles them. The empty prefix should always have this
24105 Defaults to @samp{#t}.
24108 @deftypevr {@code{namespace-configuration} parameter} mailbox-configuration-list mailboxes
24109 List of predefined mailboxes in this namespace.
24110 Defaults to @samp{()}.
24112 Available @code{mailbox-configuration} fields are:
24114 @deftypevr {@code{mailbox-configuration} parameter} string name
24115 Name for this mailbox.
24118 @deftypevr {@code{mailbox-configuration} parameter} string auto
24119 @samp{create} will automatically create this mailbox.
24120 @samp{subscribe} will both create and subscribe to the mailbox.
24121 Defaults to @samp{"no"}.
24124 @deftypevr {@code{mailbox-configuration} parameter} space-separated-string-list special-use
24125 List of IMAP @code{SPECIAL-USE} attributes as specified by RFC 6154.
24126 Valid values are @code{\All}, @code{\Archive}, @code{\Drafts},
24127 @code{\Flagged}, @code{\Junk}, @code{\Sent}, and @code{\Trash}.
24128 Defaults to @samp{()}.
24135 @deftypevr {@code{dovecot-configuration} parameter} file-name base-dir
24136 Base directory where to store runtime data.
24137 Defaults to @samp{"/var/run/dovecot/"}.
24140 @deftypevr {@code{dovecot-configuration} parameter} string login-greeting
24141 Greeting message for clients.
24142 Defaults to @samp{"Dovecot ready."}.
24145 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-trusted-networks
24146 List of trusted network ranges. Connections from these IPs are
24147 allowed to override their IP addresses and ports (for logging and for
24148 authentication checks). @samp{disable-plaintext-auth} is also ignored
24149 for these networks. Typically you would specify your IMAP proxy servers
24151 Defaults to @samp{()}.
24154 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-access-sockets
24155 List of login access check sockets (e.g.@: tcpwrap).
24156 Defaults to @samp{()}.
24159 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-proctitle?
24160 Show more verbose process titles (in ps). Currently shows user name
24161 and IP address. Useful for seeing who is actually using the IMAP
24162 processes (e.g.@: shared mailboxes or if the same uid is used for multiple
24164 Defaults to @samp{#f}.
24167 @deftypevr {@code{dovecot-configuration} parameter} boolean shutdown-clients?
24168 Should all processes be killed when Dovecot master process shuts down.
24169 Setting this to @code{#f} means that Dovecot can be upgraded without
24170 forcing existing client connections to close (although that could also
24171 be a problem if the upgrade is e.g.@: due to a security fix).
24172 Defaults to @samp{#t}.
24175 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer doveadm-worker-count
24176 If non-zero, run mail commands via this many connections to doveadm
24177 server, instead of running them directly in the same process.
24178 Defaults to @samp{0}.
24181 @deftypevr {@code{dovecot-configuration} parameter} string doveadm-socket-path
24182 UNIX socket or host:port used for connecting to doveadm server.
24183 Defaults to @samp{"doveadm-server"}.
24186 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list import-environment
24187 List of environment variables that are preserved on Dovecot startup
24188 and passed down to all of its child processes. You can also give
24189 key=value pairs to always set specific settings.
24192 @deftypevr {@code{dovecot-configuration} parameter} boolean disable-plaintext-auth?
24193 Disable LOGIN command and all other plaintext authentications unless
24194 SSL/TLS is used (LOGINDISABLED capability). Note that if the remote IP
24195 matches the local IP (i.e.@: you're connecting from the same computer),
24196 the connection is considered secure and plaintext authentication is
24197 allowed. See also ssl=required setting.
24198 Defaults to @samp{#t}.
24201 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-cache-size
24202 Authentication cache size (e.g.@: @samp{#e10e6}). 0 means it's disabled.
24203 Note that bsdauth, PAM and vpopmail require @samp{cache-key} to be set
24204 for caching to be used.
24205 Defaults to @samp{0}.
24208 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-ttl
24209 Time to live for cached data. After TTL expires the cached record
24210 is no longer used, *except* if the main database lookup returns internal
24211 failure. We also try to handle password changes automatically: If
24212 user's previous authentication was successful, but this one wasn't, the
24213 cache isn't used. For now this works only with plaintext
24215 Defaults to @samp{"1 hour"}.
24218 @deftypevr {@code{dovecot-configuration} parameter} string auth-cache-negative-ttl
24219 TTL for negative hits (user not found, password mismatch).
24220 0 disables caching them completely.
24221 Defaults to @samp{"1 hour"}.
24224 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-realms
24225 List of realms for SASL authentication mechanisms that need them.
24226 You can leave it empty if you don't want to support multiple realms.
24227 Many clients simply use the first one listed here, so keep the default
24229 Defaults to @samp{()}.
24232 @deftypevr {@code{dovecot-configuration} parameter} string auth-default-realm
24233 Default realm/domain to use if none was specified. This is used for
24234 both SASL realms and appending @@domain to username in plaintext
24236 Defaults to @samp{""}.
24239 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-chars
24240 List of allowed characters in username. If the user-given username
24241 contains a character not listed in here, the login automatically fails.
24242 This is just an extra check to make sure user can't exploit any
24243 potential quote escaping vulnerabilities with SQL/LDAP databases. If
24244 you want to allow all characters, set this value to empty.
24245 Defaults to @samp{"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@@"}.
24248 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-translation
24249 Username character translations before it's looked up from
24250 databases. The value contains series of from -> to characters. For
24251 example @samp{#@@/@@} means that @samp{#} and @samp{/} characters are
24252 translated to @samp{@@}.
24253 Defaults to @samp{""}.
24256 @deftypevr {@code{dovecot-configuration} parameter} string auth-username-format
24257 Username formatting before it's looked up from databases. You can
24258 use the standard variables here, e.g.@: %Lu would lowercase the username,
24259 %n would drop away the domain if it was given, or @samp{%n-AT-%d} would
24260 change the @samp{@@} into @samp{-AT-}. This translation is done after
24261 @samp{auth-username-translation} changes.
24262 Defaults to @samp{"%Lu"}.
24265 @deftypevr {@code{dovecot-configuration} parameter} string auth-master-user-separator
24266 If you want to allow master users to log in by specifying the master
24267 username within the normal username string (i.e.@: not using SASL
24268 mechanism's support for it), you can specify the separator character
24269 here. The format is then <username><separator><master username>.
24270 UW-IMAP uses @samp{*} as the separator, so that could be a good
24272 Defaults to @samp{""}.
24275 @deftypevr {@code{dovecot-configuration} parameter} string auth-anonymous-username
24276 Username to use for users logging in with ANONYMOUS SASL
24278 Defaults to @samp{"anonymous"}.
24281 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer auth-worker-max-count
24282 Maximum number of dovecot-auth worker processes. They're used to
24283 execute blocking passdb and userdb queries (e.g.@: MySQL and PAM).
24284 They're automatically created and destroyed as needed.
24285 Defaults to @samp{30}.
24288 @deftypevr {@code{dovecot-configuration} parameter} string auth-gssapi-hostname
24289 Host name to use in GSSAPI principal names. The default is to use
24290 the name returned by gethostname(). Use @samp{$ALL} (with quotes) to
24291 allow all keytab entries.
24292 Defaults to @samp{""}.
24295 @deftypevr {@code{dovecot-configuration} parameter} string auth-krb5-keytab
24296 Kerberos keytab to use for the GSSAPI mechanism. Will use the
24297 system default (usually @file{/etc/krb5.keytab}) if not specified. You may
24298 need to change the auth service to run as root to be able to read this
24300 Defaults to @samp{""}.
24303 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-use-winbind?
24304 Do NTLM and GSS-SPNEGO authentication using Samba's winbind daemon
24305 and @samp{ntlm-auth} helper.
24306 <doc/wiki/Authentication/Mechanisms/Winbind.txt>.
24307 Defaults to @samp{#f}.
24310 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-winbind-helper-path
24311 Path for Samba's @samp{ntlm-auth} helper binary.
24312 Defaults to @samp{"/usr/bin/ntlm_auth"}.
24315 @deftypevr {@code{dovecot-configuration} parameter} string auth-failure-delay
24316 Time to delay before replying to failed authentications.
24317 Defaults to @samp{"2 secs"}.
24320 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-require-client-cert?
24321 Require a valid SSL client certificate or the authentication
24323 Defaults to @samp{#f}.
24326 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-ssl-username-from-cert?
24327 Take the username from client's SSL certificate, using
24328 @code{X509_NAME_get_text_by_NID()} which returns the subject's DN's
24330 Defaults to @samp{#f}.
24333 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list auth-mechanisms
24334 List of wanted authentication mechanisms. Supported mechanisms are:
24335 @samp{plain}, @samp{login}, @samp{digest-md5}, @samp{cram-md5},
24336 @samp{ntlm}, @samp{rpa}, @samp{apop}, @samp{anonymous}, @samp{gssapi},
24337 @samp{otp}, @samp{skey}, and @samp{gss-spnego}. NOTE: See also
24338 @samp{disable-plaintext-auth} setting.
24341 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-servers
24342 List of IPs or hostnames to all director servers, including ourself.
24343 Ports can be specified as ip:port. The default port is the same as what
24344 director service's @samp{inet-listener} is using.
24345 Defaults to @samp{()}.
24348 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list director-mail-servers
24349 List of IPs or hostnames to all backend mail servers. Ranges are
24350 allowed too, like 10.0.0.10-10.0.0.30.
24351 Defaults to @samp{()}.
24354 @deftypevr {@code{dovecot-configuration} parameter} string director-user-expire
24355 How long to redirect users to a specific server after it no longer
24356 has any connections.
24357 Defaults to @samp{"15 min"}.
24360 @deftypevr {@code{dovecot-configuration} parameter} string director-username-hash
24361 How the username is translated before being hashed. Useful values
24362 include %Ln if user can log in with or without @@domain, %Ld if mailboxes
24363 are shared within domain.
24364 Defaults to @samp{"%Lu"}.
24367 @deftypevr {@code{dovecot-configuration} parameter} string log-path
24368 Log file to use for error messages. @samp{syslog} logs to syslog,
24369 @samp{/dev/stderr} logs to stderr.
24370 Defaults to @samp{"syslog"}.
24373 @deftypevr {@code{dovecot-configuration} parameter} string info-log-path
24374 Log file to use for informational messages. Defaults to
24376 Defaults to @samp{""}.
24379 @deftypevr {@code{dovecot-configuration} parameter} string debug-log-path
24380 Log file to use for debug messages. Defaults to
24381 @samp{info-log-path}.
24382 Defaults to @samp{""}.
24385 @deftypevr {@code{dovecot-configuration} parameter} string syslog-facility
24386 Syslog facility to use if you're logging to syslog. Usually if you
24387 don't want to use @samp{mail}, you'll use local0..local7. Also other
24388 standard facilities are supported.
24389 Defaults to @samp{"mail"}.
24392 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-verbose?
24393 Log unsuccessful authentication attempts and the reasons why they
24395 Defaults to @samp{#f}.
24398 @deftypevr {@code{dovecot-configuration} parameter} string auth-verbose-passwords
24399 In case of password mismatches, log the attempted password. Valid
24400 values are no, plain and sha1. sha1 can be useful for detecting brute
24401 force password attempts vs. user simply trying the same password over
24402 and over again. You can also truncate the value to n chars by appending
24403 ":n" (e.g.@: sha1:6).
24404 Defaults to @samp{"no"}.
24407 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug?
24408 Even more verbose logging for debugging purposes. Shows for example
24410 Defaults to @samp{#f}.
24413 @deftypevr {@code{dovecot-configuration} parameter} boolean auth-debug-passwords?
24414 In case of password mismatches, log the passwords and used scheme so
24415 the problem can be debugged. Enabling this also enables
24417 Defaults to @samp{#f}.
24420 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-debug?
24421 Enable mail process debugging. This can help you figure out why
24422 Dovecot isn't finding your mails.
24423 Defaults to @samp{#f}.
24426 @deftypevr {@code{dovecot-configuration} parameter} boolean verbose-ssl?
24427 Show protocol level SSL errors.
24428 Defaults to @samp{#f}.
24431 @deftypevr {@code{dovecot-configuration} parameter} string log-timestamp
24432 Prefix for each line written to log file. % codes are in
24433 strftime(3) format.
24434 Defaults to @samp{"\"%b %d %H:%M:%S \""}.
24437 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list login-log-format-elements
24438 List of elements we want to log. The elements which have a
24439 non-empty variable value are joined together to form a comma-separated
24443 @deftypevr {@code{dovecot-configuration} parameter} string login-log-format
24444 Login log format. %s contains @samp{login-log-format-elements}
24445 string, %$ contains the data we want to log.
24446 Defaults to @samp{"%$: %s"}.
24449 @deftypevr {@code{dovecot-configuration} parameter} string mail-log-prefix
24450 Log prefix for mail processes. See doc/wiki/Variables.txt for list
24451 of possible variables you can use.
24452 Defaults to @samp{"\"%s(%u)<%@{pid@}><%@{session@}>: \""}.
24455 @deftypevr {@code{dovecot-configuration} parameter} string deliver-log-format
24456 Format to use for logging mail deliveries. You can use variables:
24459 Delivery status message (e.g.@: @samp{saved to INBOX})
24471 Defaults to @samp{"msgid=%m: %$"}.
24474 @deftypevr {@code{dovecot-configuration} parameter} string mail-location
24475 Location for users' mailboxes. The default is empty, which means
24476 that Dovecot tries to find the mailboxes automatically. This won't work
24477 if the user doesn't yet have any mail, so you should explicitly tell
24478 Dovecot the full location.
24480 If you're using mbox, giving a path to the INBOX
24481 file (e.g.@: @file{/var/mail/%u}) isn't enough. You'll also need to tell Dovecot
24482 where the other mailboxes are kept. This is called the @emph{root mail
24483 directory}, and it must be the first path given in the
24484 @samp{mail-location} setting.
24486 There are a few special variables you can use, e.g.:
24492 user part in user@@domain, same as %u if there's no domain
24494 domain part in user@@domain, empty if there's no domain
24499 See doc/wiki/Variables.txt for full list. Some examples:
24501 @item maildir:~/Maildir
24502 @item mbox:~/mail:INBOX=/var/mail/%u
24503 @item mbox:/var/mail/%d/%1n/%n:INDEX=/var/indexes/%d/%1n/%
24505 Defaults to @samp{""}.
24508 @deftypevr {@code{dovecot-configuration} parameter} string mail-uid
24509 System user and group used to access mails. If you use multiple,
24510 userdb can override these by returning uid or gid fields. You can use
24511 either numbers or names. <doc/wiki/UserIds.txt>.
24512 Defaults to @samp{""}.
24515 @deftypevr {@code{dovecot-configuration} parameter} string mail-gid
24517 Defaults to @samp{""}.
24520 @deftypevr {@code{dovecot-configuration} parameter} string mail-privileged-group
24521 Group to enable temporarily for privileged operations. Currently
24522 this is used only with INBOX when either its initial creation or
24523 dotlocking fails. Typically this is set to @samp{"mail"} to give access to
24525 Defaults to @samp{""}.
24528 @deftypevr {@code{dovecot-configuration} parameter} string mail-access-groups
24529 Grant access to these supplementary groups for mail processes.
24530 Typically these are used to set up access to shared mailboxes. Note
24531 that it may be dangerous to set these if users can create symlinks
24532 (e.g.@: if @samp{mail} group is set here, @code{ln -s /var/mail ~/mail/var}
24533 could allow a user to delete others' mailboxes, or @code{ln -s
24534 /secret/shared/box ~/mail/mybox} would allow reading it). Defaults to
24538 @deftypevr {@code{dovecot-configuration} parameter} string mail-attribute-dict
24539 The location of a dictionary used to store @code{IMAP METADATA}
24540 as defined by @uref{https://tools.ietf.org/html/rfc5464, RFC@tie{}5464}.
24542 The IMAP METADATA commands are available only if the ``imap''
24543 protocol configuration's @code{imap-metadata?} field is @samp{#t}.
24545 Defaults to @samp{""}.
24549 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-full-filesystem-access?
24550 Allow full file system access to clients. There's no access checks
24551 other than what the operating system does for the active UID/GID@. It
24552 works with both maildir and mboxes, allowing you to prefix mailboxes
24553 names with e.g.@: @file{/path/} or @file{~user/}.
24554 Defaults to @samp{#f}.
24557 @deftypevr {@code{dovecot-configuration} parameter} boolean mmap-disable?
24558 Don't use @code{mmap()} at all. This is required if you store indexes to
24559 shared file systems (NFS or clustered file system).
24560 Defaults to @samp{#f}.
24563 @deftypevr {@code{dovecot-configuration} parameter} boolean dotlock-use-excl?
24564 Rely on @samp{O_EXCL} to work when creating dotlock files. NFS
24565 supports @samp{O_EXCL} since version 3, so this should be safe to use
24566 nowadays by default.
24567 Defaults to @samp{#t}.
24570 @deftypevr {@code{dovecot-configuration} parameter} string mail-fsync
24571 When to use fsync() or fdatasync() calls:
24574 Whenever necessary to avoid losing important data
24576 Useful with e.g.@: NFS when @code{write()}s are delayed
24578 Never use it (best performance, but crashes can lose data).
24580 Defaults to @samp{"optimized"}.
24583 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-storage?
24584 Mail storage exists in NFS@. Set this to yes to make Dovecot flush
24585 NFS caches whenever needed. If you're using only a single mail server
24587 Defaults to @samp{#f}.
24590 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-nfs-index?
24591 Mail index files also exist in NFS@. Setting this to yes requires
24592 @samp{mmap-disable? #t} and @samp{fsync-disable? #f}.
24593 Defaults to @samp{#f}.
24596 @deftypevr {@code{dovecot-configuration} parameter} string lock-method
24597 Locking method for index files. Alternatives are fcntl, flock and
24598 dotlock. Dotlocking uses some tricks which may create more disk I/O
24599 than other locking methods. NFS users: flock doesn't work, remember to
24600 change @samp{mmap-disable}.
24601 Defaults to @samp{"fcntl"}.
24604 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-temp-dir
24605 Directory in which LDA/LMTP temporarily stores incoming mails >128
24607 Defaults to @samp{"/tmp"}.
24610 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-uid
24611 Valid UID range for users. This is mostly to make sure that users can't
24612 log in as daemons or other system users. Note that denying root logins is
24613 hardcoded to dovecot binary and can't be done even if @samp{first-valid-uid}
24615 Defaults to @samp{500}.
24618 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-uid
24620 Defaults to @samp{0}.
24623 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer first-valid-gid
24624 Valid GID range for users. Users having non-valid GID as primary group ID
24625 aren't allowed to log in. If user belongs to supplementary groups with
24626 non-valid GIDs, those groups are not set.
24627 Defaults to @samp{1}.
24630 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer last-valid-gid
24632 Defaults to @samp{0}.
24635 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-max-keyword-length
24636 Maximum allowed length for mail keyword name. It's only forced when
24637 trying to create new keywords.
24638 Defaults to @samp{50}.
24641 @deftypevr {@code{dovecot-configuration} parameter} colon-separated-file-name-list valid-chroot-dirs
24642 List of directories under which chrooting is allowed for mail
24643 processes (i.e.@: @file{/var/mail} will allow chrooting to @file{/var/mail/foo/bar}
24644 too). This setting doesn't affect @samp{login-chroot}
24645 @samp{mail-chroot} or auth chroot settings. If this setting is empty,
24646 @samp{/./} in home dirs are ignored. WARNING: Never add directories here
24647 which local users can modify, that may lead to root exploit. Usually
24648 this should be done only if you don't allow shell access for users.
24649 <doc/wiki/Chrooting.txt>.
24650 Defaults to @samp{()}.
24653 @deftypevr {@code{dovecot-configuration} parameter} string mail-chroot
24654 Default chroot directory for mail processes. This can be overridden
24655 for specific users in user database by giving @samp{/./} in user's home
24656 directory (e.g.@: @samp{/home/./user} chroots into @file{/home}). Note that usually
24657 there is no real need to do chrooting, Dovecot doesn't allow users to
24658 access files outside their mail directory anyway. If your home
24659 directories are prefixed with the chroot directory, append @samp{/.} to
24660 @samp{mail-chroot}. <doc/wiki/Chrooting.txt>.
24661 Defaults to @samp{""}.
24664 @deftypevr {@code{dovecot-configuration} parameter} file-name auth-socket-path
24665 UNIX socket path to master authentication server to find users.
24666 This is used by imap (for shared users) and lda.
24667 Defaults to @samp{"/var/run/dovecot/auth-userdb"}.
24670 @deftypevr {@code{dovecot-configuration} parameter} file-name mail-plugin-dir
24671 Directory where to look up mail plugins.
24672 Defaults to @samp{"/usr/lib/dovecot"}.
24675 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mail-plugins
24676 List of plugins to load for all services. Plugins specific to IMAP,
24677 LDA, etc.@: are added to this list in their own .conf files.
24678 Defaults to @samp{()}.
24681 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-cache-min-mail-count
24682 The minimum number of mails in a mailbox before updates are done to
24683 cache file. This allows optimizing Dovecot's behavior to do less disk
24684 writes at the cost of more disk reads.
24685 Defaults to @samp{0}.
24688 @deftypevr {@code{dovecot-configuration} parameter} string mailbox-idle-check-interval
24689 When IDLE command is running, mailbox is checked once in a while to
24690 see if there are any new mails or other changes. This setting defines
24691 the minimum time to wait between those checks. Dovecot can also use
24692 dnotify, inotify and kqueue to find out immediately when changes
24694 Defaults to @samp{"30 secs"}.
24697 @deftypevr {@code{dovecot-configuration} parameter} boolean mail-save-crlf?
24698 Save mails with CR+LF instead of plain LF@. This makes sending those
24699 mails take less CPU, especially with sendfile() syscall with Linux and
24700 FreeBSD@. But it also creates a bit more disk I/O which may just make it
24701 slower. Also note that if other software reads the mboxes/maildirs,
24702 they may handle the extra CRs wrong and cause problems.
24703 Defaults to @samp{#f}.
24706 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-stat-dirs?
24707 By default LIST command returns all entries in maildir beginning
24708 with a dot. Enabling this option makes Dovecot return only entries
24709 which are directories. This is done by stat()ing each entry, so it
24710 causes more disk I/O.
24711 (For systems setting struct @samp{dirent->d_type} this check is free
24712 and it's done always regardless of this setting).
24713 Defaults to @samp{#f}.
24716 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-copy-with-hardlinks?
24717 When copying a message, do it with hard links whenever possible.
24718 This makes the performance much better, and it's unlikely to have any
24720 Defaults to @samp{#t}.
24723 @deftypevr {@code{dovecot-configuration} parameter} boolean maildir-very-dirty-syncs?
24724 Assume Dovecot is the only MUA accessing Maildir: Scan cur/
24725 directory only when its mtime changes unexpectedly or when we can't find
24726 the mail otherwise.
24727 Defaults to @samp{#f}.
24730 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-read-locks
24731 Which locking methods to use for locking mbox. There are four
24736 Create <mailbox>.lock file. This is the oldest and most NFS-safe
24737 solution. If you want to use /var/mail/ like directory, the users will
24738 need write access to that directory.
24740 Same as dotlock, but if it fails because of permissions or because there
24741 isn't enough disk space, just skip it.
24743 Use this if possible. Works with NFS too if lockd is used.
24745 May not exist in all systems. Doesn't work with NFS.
24747 May not exist in all systems. Doesn't work with NFS.
24750 You can use multiple locking methods; if you do the order they're declared
24751 in is important to avoid deadlocks if other MTAs/MUAs are using multiple
24752 locking methods as well. Some operating systems don't allow using some of
24753 them simultaneously.
24756 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list mbox-write-locks
24760 @deftypevr {@code{dovecot-configuration} parameter} string mbox-lock-timeout
24761 Maximum time to wait for lock (all of them) before aborting.
24762 Defaults to @samp{"5 mins"}.
24765 @deftypevr {@code{dovecot-configuration} parameter} string mbox-dotlock-change-timeout
24766 If dotlock exists but the mailbox isn't modified in any way,
24767 override the lock file after this much time.
24768 Defaults to @samp{"2 mins"}.
24771 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-dirty-syncs?
24772 When mbox changes unexpectedly we have to fully read it to find out
24773 what changed. If the mbox is large this can take a long time. Since
24774 the change is usually just a newly appended mail, it'd be faster to
24775 simply read the new mails. If this setting is enabled, Dovecot does
24776 this but still safely fallbacks to re-reading the whole mbox file
24777 whenever something in mbox isn't how it's expected to be. The only real
24778 downside to this setting is that if some other MUA changes message
24779 flags, Dovecot doesn't notice it immediately. Note that a full sync is
24780 done with SELECT, EXAMINE, EXPUNGE and CHECK commands.
24781 Defaults to @samp{#t}.
24784 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-very-dirty-syncs?
24785 Like @samp{mbox-dirty-syncs}, but don't do full syncs even with SELECT,
24786 EXAMINE, EXPUNGE or CHECK commands. If this is set,
24787 @samp{mbox-dirty-syncs} is ignored.
24788 Defaults to @samp{#f}.
24791 @deftypevr {@code{dovecot-configuration} parameter} boolean mbox-lazy-writes?
24792 Delay writing mbox headers until doing a full write sync (EXPUNGE
24793 and CHECK commands and when closing the mailbox). This is especially
24794 useful for POP3 where clients often delete all mails. The downside is
24795 that our changes aren't immediately visible to other MUAs.
24796 Defaults to @samp{#t}.
24799 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mbox-min-index-size
24800 If mbox size is smaller than this (e.g.@: 100k), don't write index
24801 files. If an index file already exists it's still read, just not
24803 Defaults to @samp{0}.
24806 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mdbox-rotate-size
24807 Maximum dbox file size until it's rotated.
24808 Defaults to @samp{10000000}.
24811 @deftypevr {@code{dovecot-configuration} parameter} string mdbox-rotate-interval
24812 Maximum dbox file age until it's rotated. Typically in days. Day
24813 begins from midnight, so 1d = today, 2d = yesterday, etc. 0 = check
24815 Defaults to @samp{"1d"}.
24818 @deftypevr {@code{dovecot-configuration} parameter} boolean mdbox-preallocate-space?
24819 When creating new mdbox files, immediately preallocate their size to
24820 @samp{mdbox-rotate-size}. This setting currently works only in Linux
24821 with some file systems (ext4, xfs).
24822 Defaults to @samp{#f}.
24825 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-dir
24826 sdbox and mdbox support saving mail attachments to external files,
24827 which also allows single instance storage for them. Other backends
24828 don't support this for now.
24830 WARNING: This feature hasn't been tested much yet. Use at your own risk.
24832 Directory root where to store mail attachments. Disabled, if empty.
24833 Defaults to @samp{""}.
24836 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer mail-attachment-min-size
24837 Attachments smaller than this aren't saved externally. It's also
24838 possible to write a plugin to disable saving specific attachments
24840 Defaults to @samp{128000}.
24843 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-fs
24844 File system backend to use for saving attachments:
24847 No SiS done by Dovecot (but this might help FS's own deduplication)
24849 SiS with immediate byte-by-byte comparison during saving
24850 @item sis-queue posix
24851 SiS with delayed comparison and deduplication.
24853 Defaults to @samp{"sis posix"}.
24856 @deftypevr {@code{dovecot-configuration} parameter} string mail-attachment-hash
24857 Hash format to use in attachment filenames. You can add any text and
24858 variables: @code{%@{md4@}}, @code{%@{md5@}}, @code{%@{sha1@}},
24859 @code{%@{sha256@}}, @code{%@{sha512@}}, @code{%@{size@}}. Variables can be
24860 truncated, e.g.@: @code{%@{sha256:80@}} returns only first 80 bits.
24861 Defaults to @samp{"%@{sha1@}"}.
24864 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-process-limit
24866 Defaults to @samp{100}.
24869 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-client-limit
24871 Defaults to @samp{1000}.
24874 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer default-vsz-limit
24875 Default VSZ (virtual memory size) limit for service processes.
24876 This is mainly intended to catch and kill processes that leak memory
24877 before they eat up everything.
24878 Defaults to @samp{256000000}.
24881 @deftypevr {@code{dovecot-configuration} parameter} string default-login-user
24882 Login user is internally used by login processes. This is the most
24883 untrusted user in Dovecot system. It shouldn't have access to anything
24885 Defaults to @samp{"dovenull"}.
24888 @deftypevr {@code{dovecot-configuration} parameter} string default-internal-user
24889 Internal user is used by unprivileged processes. It should be
24890 separate from login user, so that login processes can't disturb other
24892 Defaults to @samp{"dovecot"}.
24895 @deftypevr {@code{dovecot-configuration} parameter} string ssl?
24896 SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>.
24897 Defaults to @samp{"required"}.
24900 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert
24901 PEM encoded X.509 SSL/TLS certificate (public key).
24902 Defaults to @samp{"</etc/dovecot/default.pem"}.
24905 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key
24906 PEM encoded SSL/TLS private key. The key is opened before
24907 dropping root privileges, so keep the key file unreadable by anyone but
24909 Defaults to @samp{"</etc/dovecot/private/default.pem"}.
24912 @deftypevr {@code{dovecot-configuration} parameter} string ssl-key-password
24913 If key file is password protected, give the password here.
24914 Alternatively give it when starting dovecot with -p parameter. Since
24915 this file is often world-readable, you may want to place this setting
24916 instead to a different.
24917 Defaults to @samp{""}.
24920 @deftypevr {@code{dovecot-configuration} parameter} string ssl-ca
24921 PEM encoded trusted certificate authority. Set this only if you
24922 intend to use @samp{ssl-verify-client-cert? #t}. The file should
24923 contain the CA certificate(s) followed by the matching
24924 CRL(s). (e.g.@: @samp{ssl-ca </etc/ssl/certs/ca.pem}).
24925 Defaults to @samp{""}.
24928 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-require-crl?
24929 Require that CRL check succeeds for client certificates.
24930 Defaults to @samp{#t}.
24933 @deftypevr {@code{dovecot-configuration} parameter} boolean ssl-verify-client-cert?
24934 Request client to send a certificate. If you also want to require
24935 it, set @samp{auth-ssl-require-client-cert? #t} in auth section.
24936 Defaults to @samp{#f}.
24939 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cert-username-field
24940 Which field from certificate to use for username. commonName and
24941 x500UniqueIdentifier are the usual choices. You'll also need to set
24942 @samp{auth-ssl-username-from-cert? #t}.
24943 Defaults to @samp{"commonName"}.
24946 @deftypevr {@code{dovecot-configuration} parameter} string ssl-min-protocol
24947 Minimum SSL protocol version to accept.
24948 Defaults to @samp{"TLSv1"}.
24951 @deftypevr {@code{dovecot-configuration} parameter} string ssl-cipher-list
24952 SSL ciphers to use.
24953 Defaults to @samp{"ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@@STRENGTH"}.
24956 @deftypevr {@code{dovecot-configuration} parameter} string ssl-crypto-device
24957 SSL crypto device to use, for valid values run "openssl engine".
24958 Defaults to @samp{""}.
24961 @deftypevr {@code{dovecot-configuration} parameter} string postmaster-address
24962 Address to use when sending rejection mails.
24963 %d expands to recipient domain.
24964 Defaults to @samp{"postmaster@@%d"}.
24967 @deftypevr {@code{dovecot-configuration} parameter} string hostname
24968 Hostname to use in various parts of sent mails (e.g.@: in Message-Id)
24969 and in LMTP replies. Default is the system's real hostname@@domain.
24970 Defaults to @samp{""}.
24973 @deftypevr {@code{dovecot-configuration} parameter} boolean quota-full-tempfail?
24974 If user is over quota, return with temporary failure instead of
24976 Defaults to @samp{#f}.
24979 @deftypevr {@code{dovecot-configuration} parameter} file-name sendmail-path
24980 Binary to use for sending mails.
24981 Defaults to @samp{"/usr/sbin/sendmail"}.
24984 @deftypevr {@code{dovecot-configuration} parameter} string submission-host
24985 If non-empty, send mails via this SMTP host[:port] instead of
24987 Defaults to @samp{""}.
24990 @deftypevr {@code{dovecot-configuration} parameter} string rejection-subject
24991 Subject: header to use for rejection mails. You can use the same
24992 variables as for @samp{rejection-reason} below.
24993 Defaults to @samp{"Rejected: %s"}.
24996 @deftypevr {@code{dovecot-configuration} parameter} string rejection-reason
24997 Human readable error message for rejection mails. You can use
25010 Defaults to @samp{"Your message to <%t> was automatically rejected:%n%r"}.
25013 @deftypevr {@code{dovecot-configuration} parameter} string recipient-delimiter
25014 Delimiter character between local-part and detail in email
25016 Defaults to @samp{"+"}.
25019 @deftypevr {@code{dovecot-configuration} parameter} string lda-original-recipient-header
25020 Header where the original recipient address (SMTP's RCPT TO:
25021 address) is taken from if not available elsewhere. With dovecot-lda -a
25022 parameter overrides this. A commonly used header for this is
25024 Defaults to @samp{""}.
25027 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autocreate?
25028 Should saving a mail to a nonexistent mailbox automatically create
25030 Defaults to @samp{#f}.
25033 @deftypevr {@code{dovecot-configuration} parameter} boolean lda-mailbox-autosubscribe?
25034 Should automatically created mailboxes be also automatically
25036 Defaults to @samp{#f}.
25039 @deftypevr {@code{dovecot-configuration} parameter} non-negative-integer imap-max-line-length
25040 Maximum IMAP command line length. Some clients generate very long
25041 command lines with huge mailboxes, so you may need to raise this if you
25042 get "Too long argument" or "IMAP command line too large" errors
25044 Defaults to @samp{64000}.
25047 @deftypevr {@code{dovecot-configuration} parameter} string imap-logout-format
25048 IMAP logout format string:
25051 total number of bytes read from client
25053 total number of bytes sent to client.
25055 See @file{doc/wiki/Variables.txt} for a list of all the variables you can use.
25056 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@}"}.
25059 @deftypevr {@code{dovecot-configuration} parameter} string imap-capability
25060 Override the IMAP CAPABILITY response. If the value begins with '+',
25061 add the given capabilities on top of the defaults (e.g.@: +XFOO XBAR).
25062 Defaults to @samp{""}.
25065 @deftypevr {@code{dovecot-configuration} parameter} string imap-idle-notify-interval
25066 How long to wait between "OK Still here" notifications when client
25068 Defaults to @samp{"2 mins"}.
25071 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-send
25072 ID field names and values to send to clients. Using * as the value
25073 makes Dovecot use the default value. The following fields have default
25074 values currently: name, version, os, os-version, support-url,
25076 Defaults to @samp{""}.
25079 @deftypevr {@code{dovecot-configuration} parameter} string imap-id-log
25080 ID fields sent by client to log. * means everything.
25081 Defaults to @samp{""}.
25084 @deftypevr {@code{dovecot-configuration} parameter} space-separated-string-list imap-client-workarounds
25085 Workarounds for various client bugs:
25088 @item delay-newmail
25089 Send EXISTS/RECENT new mail notifications only when replying to NOOP and
25090 CHECK commands. Some clients ignore them otherwise, for example OSX
25091 Mail (<v2.1). Outlook Express breaks more badly though, without this it
25092 may show user "Message no longer in server" errors. Note that OE6
25093 still breaks even with this workaround if synchronization is set to
25096 @item tb-extra-mailbox-sep
25097 Thunderbird gets somehow confused with LAYOUT=fs (mbox and dbox) and
25098 adds extra @samp{/} suffixes to mailbox names. This option causes Dovecot to
25099 ignore the extra @samp{/} instead of treating it as invalid mailbox name.
25101 @item tb-lsub-flags
25102 Show \Noselect flags for LSUB replies with LAYOUT=fs (e.g.@: mbox).
25103 This makes Thunderbird realize they aren't selectable and show them
25104 greyed out, instead of only later giving "not selectable" popup error.
25106 Defaults to @samp{()}.
25109 @deftypevr {@code{dovecot-configuration} parameter} string imap-urlauth-host
25110 Host allowed in URLAUTH URLs sent by client. "*" allows all.
25111 Defaults to @samp{""}.
25115 Whew! Lots of configuration options. The nice thing about it though is
25116 that Guix has a complete interface to Dovecot's configuration
25117 language. This allows not only a nice way to declare configurations,
25118 but also offers reflective capabilities as well: users can write code to
25119 inspect and transform configurations from within Scheme.
25121 However, it could be that you just want to get a @code{dovecot.conf} up
25122 and running. In that case, you can pass an
25123 @code{opaque-dovecot-configuration} as the @code{#:config} parameter to
25124 @code{dovecot-service}. As its name indicates, an opaque configuration
25125 does not have easy reflective capabilities.
25127 Available @code{opaque-dovecot-configuration} fields are:
25129 @deftypevr {@code{opaque-dovecot-configuration} parameter} package dovecot
25130 The dovecot package.
25133 @deftypevr {@code{opaque-dovecot-configuration} parameter} string string
25134 The contents of the @code{dovecot.conf}, as a string.
25137 For example, if your @code{dovecot.conf} is just the empty string, you
25138 could instantiate a dovecot service like this:
25141 (dovecot-service #:config
25142 (opaque-dovecot-configuration
25146 @subsubheading OpenSMTPD Service
25148 @deffn {Scheme Variable} opensmtpd-service-type
25149 This is the type of the @uref{https://www.opensmtpd.org, OpenSMTPD}
25150 service, whose value should be an @code{opensmtpd-configuration} object
25151 as in this example:
25154 (service opensmtpd-service-type
25155 (opensmtpd-configuration
25156 (config-file (local-file "./my-smtpd.conf"))))
25160 @deftp {Data Type} opensmtpd-configuration
25161 Data type representing the configuration of opensmtpd.
25164 @item @code{package} (default: @var{opensmtpd})
25165 Package object of the OpenSMTPD SMTP server.
25167 @item @code{config-file} (default: @code{%default-opensmtpd-config-file})
25168 File-like object of the OpenSMTPD configuration file to use. By default
25169 it listens on the loopback network interface, and allows for mail from
25170 users and daemons on the local machine, as well as permitting email to
25171 remote servers. Run @command{man smtpd.conf} for more information.
25173 @item @code{setgid-commands?} (default: @code{#t})
25174 Make the following commands setgid to @code{smtpq} so they can be
25175 executed: @command{smtpctl}, @command{sendmail}, @command{send-mail},
25176 @command{makemap}, @command{mailq}, and @command{newaliases}.
25177 @xref{Setuid Programs}, for more information on setgid programs.
25181 @subsubheading Exim Service
25183 @cindex mail transfer agent (MTA)
25184 @cindex MTA (mail transfer agent)
25187 @deffn {Scheme Variable} exim-service-type
25188 This is the type of the @uref{https://exim.org, Exim} mail transfer
25189 agent (MTA), whose value should be an @code{exim-configuration} object
25190 as in this example:
25193 (service exim-service-type
25194 (exim-configuration
25195 (config-file (local-file "./my-exim.conf"))))
25199 In order to use an @code{exim-service-type} service you must also have a
25200 @code{mail-aliases-service-type} service present in your
25201 @code{operating-system} (even if it has no aliases).
25203 @deftp {Data Type} exim-configuration
25204 Data type representing the configuration of exim.
25207 @item @code{package} (default: @var{exim})
25208 Package object of the Exim server.
25210 @item @code{config-file} (default: @code{#f})
25211 File-like object of the Exim configuration file to use. If its value is
25212 @code{#f} then use the default configuration file from the package
25213 provided in @code{package}. The resulting configuration file is loaded
25214 after setting the @code{exim_user} and @code{exim_group} configuration
25220 @subsubheading Getmail service
25225 @deffn {Scheme Variable} getmail-service-type
25226 This is the type of the @uref{http://pyropus.ca/software/getmail/, Getmail}
25227 mail retriever, whose value should be an @code{getmail-configuration}.
25230 Available @code{getmail-configuration} fields are:
25232 @deftypevr {@code{getmail-configuration} parameter} symbol name
25233 A symbol to identify the getmail service.
25235 Defaults to @samp{"unset"}.
25239 @deftypevr {@code{getmail-configuration} parameter} package package
25240 The getmail package to use.
25244 @deftypevr {@code{getmail-configuration} parameter} string user
25245 The user to run getmail as.
25247 Defaults to @samp{"getmail"}.
25251 @deftypevr {@code{getmail-configuration} parameter} string group
25252 The group to run getmail as.
25254 Defaults to @samp{"getmail"}.
25258 @deftypevr {@code{getmail-configuration} parameter} string directory
25259 The getmail directory to use.
25261 Defaults to @samp{"/var/lib/getmail/default"}.
25265 @deftypevr {@code{getmail-configuration} parameter} getmail-configuration-file rcfile
25266 The getmail configuration file to use.
25268 Available @code{getmail-configuration-file} fields are:
25270 @deftypevr {@code{getmail-configuration-file} parameter} getmail-retriever-configuration retriever
25271 What mail account to retrieve mail from, and how to access that account.
25273 Available @code{getmail-retriever-configuration} fields are:
25275 @deftypevr {@code{getmail-retriever-configuration} parameter} string type
25276 The type of mail retriever to use. Valid values include @samp{passwd}
25279 Defaults to @samp{"SimpleIMAPSSLRetriever"}.
25283 @deftypevr {@code{getmail-retriever-configuration} parameter} string server
25284 Username to login to the mail server with.
25286 Defaults to @samp{unset}.
25290 @deftypevr {@code{getmail-retriever-configuration} parameter} string username
25291 Username to login to the mail server with.
25293 Defaults to @samp{unset}.
25297 @deftypevr {@code{getmail-retriever-configuration} parameter} non-negative-integer port
25298 Port number to connect to.
25300 Defaults to @samp{#f}.
25304 @deftypevr {@code{getmail-retriever-configuration} parameter} string password
25305 Override fields from passwd.
25307 Defaults to @samp{""}.
25311 @deftypevr {@code{getmail-retriever-configuration} parameter} list password-command
25312 Override fields from passwd.
25314 Defaults to @samp{()}.
25318 @deftypevr {@code{getmail-retriever-configuration} parameter} string keyfile
25319 PEM-formatted key file to use for the TLS negotiation.
25321 Defaults to @samp{""}.
25325 @deftypevr {@code{getmail-retriever-configuration} parameter} string certfile
25326 PEM-formatted certificate file to use for the TLS negotiation.
25328 Defaults to @samp{""}.
25332 @deftypevr {@code{getmail-retriever-configuration} parameter} string ca-certs
25333 CA certificates to use.
25335 Defaults to @samp{""}.
25339 @deftypevr {@code{getmail-retriever-configuration} parameter} parameter-alist extra-parameters
25340 Extra retriever parameters.
25342 Defaults to @samp{()}.
25348 @deftypevr {@code{getmail-configuration-file} parameter} getmail-destination-configuration destination
25349 What to do with retrieved messages.
25351 Available @code{getmail-destination-configuration} fields are:
25353 @deftypevr {@code{getmail-destination-configuration} parameter} string type
25354 The type of mail destination. Valid values include @samp{Maildir},
25355 @samp{Mboxrd} and @samp{MDA_external}.
25357 Defaults to @samp{unset}.
25361 @deftypevr {@code{getmail-destination-configuration} parameter} string-or-filelike path
25362 The path option for the mail destination. The behaviour depends on the
25365 Defaults to @samp{""}.
25369 @deftypevr {@code{getmail-destination-configuration} parameter} parameter-alist extra-parameters
25370 Extra destination parameters
25372 Defaults to @samp{()}.
25378 @deftypevr {@code{getmail-configuration-file} parameter} getmail-options-configuration options
25381 Available @code{getmail-options-configuration} fields are:
25383 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer verbose
25384 If set to @samp{0}, getmail will only print warnings and errors. A
25385 value of @samp{1} means that messages will be printed about retrieving
25386 and deleting messages. If set to @samp{2}, getmail will print messages
25387 about each of its actions.
25389 Defaults to @samp{1}.
25393 @deftypevr {@code{getmail-options-configuration} parameter} boolean read-all
25394 If true, getmail will retrieve all available messages. Otherwise it
25395 will only retrieve messages it hasn't seen previously.
25397 Defaults to @samp{#t}.
25401 @deftypevr {@code{getmail-options-configuration} parameter} boolean delete
25402 If set to true, messages will be deleted from the server after
25403 retrieving and successfully delivering them. Otherwise, messages will
25404 be left on the server.
25406 Defaults to @samp{#f}.
25410 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-after
25411 Getmail will delete messages this number of days after seeing them, if
25412 they have been delivered. This means messages will be left on the
25413 server this number of days after delivering them. A value of @samp{0}
25414 disabled this feature.
25416 Defaults to @samp{0}.
25420 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer delete-bigger-than
25421 Delete messages larger than this of bytes after retrieving them, even if
25422 the delete and delete-after options are disabled. A value of @samp{0}
25423 disables this feature.
25425 Defaults to @samp{0}.
25429 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-bytes-per-session
25430 Retrieve messages totalling up to this number of bytes before closing
25431 the session with the server. A value of @samp{0} disables this feature.
25433 Defaults to @samp{0}.
25437 @deftypevr {@code{getmail-options-configuration} parameter} non-negative-integer max-message-size
25438 Don't retrieve messages larger than this number of bytes. A value of
25439 @samp{0} disables this feature.
25441 Defaults to @samp{0}.
25445 @deftypevr {@code{getmail-options-configuration} parameter} boolean delivered-to
25446 If true, getmail will add a Delivered-To header to messages.
25448 Defaults to @samp{#t}.
25452 @deftypevr {@code{getmail-options-configuration} parameter} boolean received
25453 If set, getmail adds a Received header to the messages.
25455 Defaults to @samp{#t}.
25459 @deftypevr {@code{getmail-options-configuration} parameter} string message-log
25460 Getmail will record a log of its actions to the named file. A value of
25461 @samp{""} disables this feature.
25463 Defaults to @samp{""}.
25467 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-syslog
25468 If true, getmail will record a log of its actions using the system
25471 Defaults to @samp{#f}.
25475 @deftypevr {@code{getmail-options-configuration} parameter} boolean message-log-verbose
25476 If true, getmail will log information about messages not retrieved and
25477 the reason for not retrieving them, as well as starting and ending
25480 Defaults to @samp{#f}.
25484 @deftypevr {@code{getmail-options-configuration} parameter} parameter-alist extra-parameters
25485 Extra options to include.
25487 Defaults to @samp{()}.
25495 @deftypevr {@code{getmail-configuration} parameter} list idle
25496 A list of mailboxes that getmail should wait on the server for new mail
25497 notifications. This depends on the server supporting the IDLE
25500 Defaults to @samp{()}.
25504 @deftypevr {@code{getmail-configuration} parameter} list environment-variables
25505 Environment variables to set for getmail.
25507 Defaults to @samp{()}.
25511 @subsubheading Mail Aliases Service
25513 @cindex email aliases
25514 @cindex aliases, for email addresses
25516 @deffn {Scheme Variable} mail-aliases-service-type
25517 This is the type of the service which provides @code{/etc/aliases},
25518 specifying how to deliver mail to users on this system.
25521 (service mail-aliases-service-type
25522 '(("postmaster" "bob")
25523 ("bob" "bob@@example.com" "bob@@example2.com")))
25527 The configuration for a @code{mail-aliases-service-type} service is an
25528 association list denoting how to deliver mail that comes to this
25529 system. Each entry is of the form @code{(alias addresses ...)}, with
25530 @code{alias} specifying the local alias and @code{addresses} specifying
25531 where to deliver this user's mail.
25533 The aliases aren't required to exist as users on the local system. In
25534 the above example, there doesn't need to be a @code{postmaster} entry in
25535 the @code{operating-system}'s @code{user-accounts} in order to deliver
25536 the @code{postmaster} mail to @code{bob} (which subsequently would
25537 deliver mail to @code{bob@@example.com} and @code{bob@@example2.com}).
25539 @subsubheading GNU Mailutils IMAP4 Daemon
25540 @cindex GNU Mailutils IMAP4 Daemon
25542 @deffn {Scheme Variable} imap4d-service-type
25543 This is the type of the GNU Mailutils IMAP4 Daemon (@pxref{imap4d,,,
25544 mailutils, GNU Mailutils Manual}), whose value should be an
25545 @code{imap4d-configuration} object as in this example:
25548 (service imap4d-service-type
25549 (imap4d-configuration
25550 (config-file (local-file "imap4d.conf"))))
25554 @deftp {Data Type} imap4d-configuration
25555 Data type representing the configuration of @command{imap4d}.
25558 @item @code{package} (default: @code{mailutils})
25559 The package that provides @command{imap4d}.
25561 @item @code{config-file} (default: @code{%default-imap4d-config-file})
25562 File-like object of the configuration file to use, by default it will listen
25563 on TCP port 143 of @code{localhost}. @xref{Conf-imap4d,,, mailutils, GNU
25564 Mailutils Manual}, for details.
25569 @subsubheading Radicale Service
25573 @deffn {Scheme Variable} radicale-service-type
25574 This is the type of the @uref{https://radicale.org, Radicale} CalDAV/CardDAV
25575 server whose value should be a @code{radicale-configuration}.
25578 @deftp {Data Type} radicale-configuration
25579 Data type representing the configuration of @command{radicale}.
25582 @item @code{package} (default: @code{radicale})
25583 The package that provides @command{radicale}.
25585 @item @code{config-file} (default: @code{%default-radicale-config-file})
25586 File-like object of the configuration file to use, by default it will listen
25587 on TCP port 5232 of @code{localhost} and use the @code{htpasswd} file at
25588 @file{/var/lib/radicale/users} with no (@code{plain}) encryption.
25593 @node Messaging Services
25594 @subsection Messaging Services
25599 The @code{(gnu services messaging)} module provides Guix service
25600 definitions for messaging services. Currently it provides the following
25603 @subsubheading Prosody Service
25605 @deffn {Scheme Variable} prosody-service-type
25606 This is the type for the @uref{https://prosody.im, Prosody XMPP
25607 communication server}. Its value must be a @code{prosody-configuration}
25608 record as in this example:
25611 (service prosody-service-type
25612 (prosody-configuration
25613 (modules-enabled (cons* "groups" "mam" %default-modules-enabled))
25616 (int-component-configuration
25617 (hostname "conference.example.net")
25619 (mod-muc (mod-muc-configuration)))))
25622 (virtualhost-configuration
25623 (domain "example.net"))))))
25626 See below for details about @code{prosody-configuration}.
25630 By default, Prosody does not need much configuration. Only one
25631 @code{virtualhosts} field is needed: it specifies the domain you wish
25634 You can perform various sanity checks on the generated configuration
25635 with the @code{prosodyctl check} command.
25637 Prosodyctl will also help you to import certificates from the
25638 @code{letsencrypt} directory so that the @code{prosody} user can access
25639 them. See @url{https://prosody.im/doc/letsencrypt}.
25642 prosodyctl --root cert import /etc/letsencrypt/live
25645 The available configuration parameters follow. Each parameter
25646 definition is preceded by its type; for example, @samp{string-list foo}
25647 indicates that the @code{foo} parameter should be specified as a list of
25648 strings. Types starting with @code{maybe-} denote parameters that won't
25649 show up in @code{prosody.cfg.lua} when their value is left unspecified.
25651 There is also a way to specify the configuration as a string, if you
25652 have an old @code{prosody.cfg.lua} file that you want to port over from
25653 some other system; see the end for more details.
25655 The @code{file-object} type designates either a file-like object
25656 (@pxref{G-Expressions, file-like objects}) or a file name.
25658 @c The following documentation was initially generated by
25659 @c (generate-documentation) in (gnu services messaging). Manually maintained
25660 @c documentation is better, so we shouldn't hesitate to edit below as
25661 @c needed. However if the change you want to make to this documentation
25662 @c can be done in an automated way, it's probably easier to change
25663 @c (generate-documentation) than to make it below and have to deal with
25664 @c the churn as Prosody updates.
25666 Available @code{prosody-configuration} fields are:
25668 @deftypevr {@code{prosody-configuration} parameter} package prosody
25669 The Prosody package.
25672 @deftypevr {@code{prosody-configuration} parameter} file-name data-path
25673 Location of the Prosody data storage directory. See
25674 @url{https://prosody.im/doc/configure}.
25675 Defaults to @samp{"/var/lib/prosody"}.
25678 @deftypevr {@code{prosody-configuration} parameter} file-object-list plugin-paths
25679 Additional plugin directories. They are searched in all the specified
25680 paths in order. See @url{https://prosody.im/doc/plugins_directory}.
25681 Defaults to @samp{()}.
25684 @deftypevr {@code{prosody-configuration} parameter} file-name certificates
25685 Every virtual host and component needs a certificate so that clients and
25686 servers can securely verify its identity. Prosody will automatically load
25687 certificates/keys from the directory specified here.
25688 Defaults to @samp{"/etc/prosody/certs"}.
25691 @deftypevr {@code{prosody-configuration} parameter} string-list admins
25692 This is a list of accounts that are admins for the server. Note that you
25693 must create the accounts separately. See @url{https://prosody.im/doc/admins} and
25694 @url{https://prosody.im/doc/creating_accounts}.
25695 Example: @code{(admins '("user1@@example.com" "user2@@example.net"))}
25696 Defaults to @samp{()}.
25699 @deftypevr {@code{prosody-configuration} parameter} boolean use-libevent?
25700 Enable use of libevent for better performance under high load. See
25701 @url{https://prosody.im/doc/libevent}.
25702 Defaults to @samp{#f}.
25705 @deftypevr {@code{prosody-configuration} parameter} module-list modules-enabled
25706 This is the list of modules Prosody will load on startup. It looks for
25707 @code{mod_modulename.lua} in the plugins folder, so make sure that exists too.
25708 Documentation on modules can be found at:
25709 @url{https://prosody.im/doc/modules}.
25710 Defaults to @samp{("roster" "saslauth" "tls" "dialback" "disco" "carbons" "private" "blocklist" "vcard" "version" "uptime" "time" "ping" "pep" "register" "admin_adhoc")}.
25713 @deftypevr {@code{prosody-configuration} parameter} string-list modules-disabled
25714 @samp{"offline"}, @samp{"c2s"} and @samp{"s2s"} are auto-loaded, but
25715 should you want to disable them then add them to this list.
25716 Defaults to @samp{()}.
25719 @deftypevr {@code{prosody-configuration} parameter} file-object groups-file
25720 Path to a text file where the shared groups are defined. If this path is
25721 empty then @samp{mod_groups} does nothing. See
25722 @url{https://prosody.im/doc/modules/mod_groups}.
25723 Defaults to @samp{"/var/lib/prosody/sharedgroups.txt"}.
25726 @deftypevr {@code{prosody-configuration} parameter} boolean allow-registration?
25727 Disable account creation by default, for security. See
25728 @url{https://prosody.im/doc/creating_accounts}.
25729 Defaults to @samp{#f}.
25732 @deftypevr {@code{prosody-configuration} parameter} maybe-ssl-configuration ssl
25733 These are the SSL/TLS-related settings. Most of them are disabled so to
25734 use Prosody's defaults. If you do not completely understand these options, do
25735 not add them to your config, it is easy to lower the security of your server
25736 using them. See @url{https://prosody.im/doc/advanced_ssl_config}.
25738 Available @code{ssl-configuration} fields are:
25740 @deftypevr {@code{ssl-configuration} parameter} maybe-string protocol
25741 This determines what handshake to use.
25744 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name key
25745 Path to your private key file.
25748 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name certificate
25749 Path to your certificate file.
25752 @deftypevr {@code{ssl-configuration} parameter} file-object capath
25753 Path to directory containing root certificates that you wish Prosody to
25754 trust when verifying the certificates of remote servers.
25755 Defaults to @samp{"/etc/ssl/certs"}.
25758 @deftypevr {@code{ssl-configuration} parameter} maybe-file-object cafile
25759 Path to a file containing root certificates that you wish Prosody to trust.
25760 Similar to @code{capath} but with all certificates concatenated together.
25763 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verify
25764 A list of verification options (these mostly map to OpenSSL's
25765 @code{set_verify()} flags).
25768 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list options
25769 A list of general options relating to SSL/TLS@. These map to OpenSSL's
25770 @code{set_options()}. For a full list of options available in LuaSec, see the
25774 @deftypevr {@code{ssl-configuration} parameter} maybe-non-negative-integer depth
25775 How long a chain of certificate authorities to check when looking for a
25776 trusted root certificate.
25779 @deftypevr {@code{ssl-configuration} parameter} maybe-string ciphers
25780 An OpenSSL cipher string. This selects what ciphers Prosody will offer to
25781 clients, and in what order.
25784 @deftypevr {@code{ssl-configuration} parameter} maybe-file-name dhparam
25785 A path to a file containing parameters for Diffie-Hellman key exchange. You
25786 can create such a file with:
25787 @code{openssl dhparam -out /etc/prosody/certs/dh-2048.pem 2048}
25790 @deftypevr {@code{ssl-configuration} parameter} maybe-string curve
25791 Curve for Elliptic curve Diffie-Hellman. Prosody's default is
25792 @samp{"secp384r1"}.
25795 @deftypevr {@code{ssl-configuration} parameter} maybe-string-list verifyext
25796 A list of ``extra'' verification options.
25799 @deftypevr {@code{ssl-configuration} parameter} maybe-string password
25800 Password for encrypted private keys.
25805 @deftypevr {@code{prosody-configuration} parameter} boolean c2s-require-encryption?
25806 Whether to force all client-to-server connections to be encrypted or not.
25807 See @url{https://prosody.im/doc/modules/mod_tls}.
25808 Defaults to @samp{#f}.
25811 @deftypevr {@code{prosody-configuration} parameter} string-list disable-sasl-mechanisms
25812 Set of mechanisms that will never be offered. See
25813 @url{https://prosody.im/doc/modules/mod_saslauth}.
25814 Defaults to @samp{("DIGEST-MD5")}.
25817 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-require-encryption?
25818 Whether to force all server-to-server connections to be encrypted or not.
25819 See @url{https://prosody.im/doc/modules/mod_tls}.
25820 Defaults to @samp{#f}.
25823 @deftypevr {@code{prosody-configuration} parameter} boolean s2s-secure-auth?
25824 Whether to require encryption and certificate authentication. This
25825 provides ideal security, but requires servers you communicate with to support
25826 encryption AND present valid, trusted certificates. See
25827 @url{https://prosody.im/doc/s2s#security}.
25828 Defaults to @samp{#f}.
25831 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-insecure-domains
25832 Many servers don't support encryption or have invalid or self-signed
25833 certificates. You can list domains here that will not be required to
25834 authenticate using certificates. They will be authenticated using DNS@. See
25835 @url{https://prosody.im/doc/s2s#security}.
25836 Defaults to @samp{()}.
25839 @deftypevr {@code{prosody-configuration} parameter} string-list s2s-secure-domains
25840 Even if you leave @code{s2s-secure-auth?} disabled, you can still require
25841 valid certificates for some domains by specifying a list here. See
25842 @url{https://prosody.im/doc/s2s#security}.
25843 Defaults to @samp{()}.
25846 @deftypevr {@code{prosody-configuration} parameter} string authentication
25847 Select the authentication backend to use. The default provider stores
25848 passwords in plaintext and uses Prosody's configured data storage to store the
25849 authentication data. If you do not trust your server please see
25850 @url{https://prosody.im/doc/modules/mod_auth_internal_hashed} for information
25851 about using the hashed backend. See also
25852 @url{https://prosody.im/doc/authentication}
25853 Defaults to @samp{"internal_plain"}.
25856 @deftypevr {@code{prosody-configuration} parameter} maybe-string log
25857 Set logging options. Advanced logging configuration is not yet supported
25858 by the Prosody service. See @url{https://prosody.im/doc/logging}.
25859 Defaults to @samp{"*syslog"}.
25862 @deftypevr {@code{prosody-configuration} parameter} file-name pidfile
25863 File to write pid in. See @url{https://prosody.im/doc/modules/mod_posix}.
25864 Defaults to @samp{"/var/run/prosody/prosody.pid"}.
25867 @deftypevr {@code{prosody-configuration} parameter} maybe-non-negative-integer http-max-content-size
25868 Maximum allowed size of the HTTP body (in bytes).
25871 @deftypevr {@code{prosody-configuration} parameter} maybe-string http-external-url
25872 Some modules expose their own URL in various ways. This URL is built
25873 from the protocol, host and port used. If Prosody sits behind a proxy, the
25874 public URL will be @code{http-external-url} instead. See
25875 @url{https://prosody.im/doc/http#external_url}.
25878 @deftypevr {@code{prosody-configuration} parameter} virtualhost-configuration-list virtualhosts
25879 A host in Prosody is a domain on which user accounts can be created. For
25880 example if you want your users to have addresses like
25881 @samp{"john.smith@@example.com"} then you need to add a host
25882 @samp{"example.com"}. All options in this list will apply only to this host.
25885 The name @emph{virtual} host is used in configuration to avoid confusion with
25886 the actual physical host that Prosody is installed on. A single Prosody
25887 instance can serve many domains, each one defined as a VirtualHost entry in
25888 Prosody's configuration. Conversely a server that hosts a single domain would
25889 have just one VirtualHost entry.
25891 See @url{https://prosody.im/doc/configure#virtual_host_settings}.
25894 Available @code{virtualhost-configuration} fields are:
25896 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:
25897 @deftypevr {@code{virtualhost-configuration} parameter} string domain
25898 Domain you wish Prosody to serve.
25903 @deftypevr {@code{prosody-configuration} parameter} int-component-configuration-list int-components
25904 Components are extra services on a server which are available to clients,
25905 usually on a subdomain of the main server (such as
25906 @samp{"mycomponent.example.com"}). Example components might be chatroom
25907 servers, user directories, or gateways to other protocols.
25909 Internal components are implemented with Prosody-specific plugins. To add an
25910 internal component, you simply fill the hostname field, and the plugin you wish
25911 to use for the component.
25913 See @url{https://prosody.im/doc/components}.
25914 Defaults to @samp{()}.
25916 Available @code{int-component-configuration} fields are:
25918 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:
25919 @deftypevr {@code{int-component-configuration} parameter} string hostname
25920 Hostname of the component.
25923 @deftypevr {@code{int-component-configuration} parameter} string plugin
25924 Plugin you wish to use for the component.
25927 @deftypevr {@code{int-component-configuration} parameter} maybe-mod-muc-configuration mod-muc
25928 Multi-user chat (MUC) is Prosody's module for allowing you to create
25929 hosted chatrooms/conferences for XMPP users.
25931 General information on setting up and using multi-user chatrooms can be found
25932 in the ``Chatrooms'' documentation (@url{https://prosody.im/doc/chatrooms}),
25933 which you should read if you are new to XMPP chatrooms.
25935 See also @url{https://prosody.im/doc/modules/mod_muc}.
25937 Available @code{mod-muc-configuration} fields are:
25939 @deftypevr {@code{mod-muc-configuration} parameter} string name
25940 The name to return in service discovery responses.
25941 Defaults to @samp{"Prosody Chatrooms"}.
25944 @deftypevr {@code{mod-muc-configuration} parameter} string-or-boolean restrict-room-creation
25945 If @samp{#t}, this will only allow admins to create new chatrooms.
25946 Otherwise anyone can create a room. The value @samp{"local"} restricts room
25947 creation to users on the service's parent domain. E.g.@: @samp{user@@example.com}
25948 can create rooms on @samp{rooms.example.com}. The value @samp{"admin"}
25949 restricts to service administrators only.
25950 Defaults to @samp{#f}.
25953 @deftypevr {@code{mod-muc-configuration} parameter} non-negative-integer max-history-messages
25954 Maximum number of history messages that will be sent to the member that has
25955 just joined the room.
25956 Defaults to @samp{20}.
25963 @deftypevr {@code{prosody-configuration} parameter} ext-component-configuration-list ext-components
25964 External components use XEP-0114, which most standalone components
25965 support. To add an external component, you simply fill the hostname field. See
25966 @url{https://prosody.im/doc/components}.
25967 Defaults to @samp{()}.
25969 Available @code{ext-component-configuration} fields are:
25971 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:
25972 @deftypevr {@code{ext-component-configuration} parameter} string component-secret
25973 Password which the component will use to log in.
25976 @deftypevr {@code{ext-component-configuration} parameter} string hostname
25977 Hostname of the component.
25982 @deftypevr {@code{prosody-configuration} parameter} non-negative-integer-list component-ports
25983 Port(s) Prosody listens on for component connections.
25984 Defaults to @samp{(5347)}.
25987 @deftypevr {@code{prosody-configuration} parameter} string component-interface
25988 Interface Prosody listens on for component connections.
25989 Defaults to @samp{"127.0.0.1"}.
25992 @deftypevr {@code{prosody-configuration} parameter} maybe-raw-content raw-content
25993 Raw content that will be added to the configuration file.
25996 It could be that you just want to get a @code{prosody.cfg.lua}
25997 up and running. In that case, you can pass an
25998 @code{opaque-prosody-configuration} record as the value of
25999 @code{prosody-service-type}. As its name indicates, an opaque configuration
26000 does not have easy reflective capabilities.
26001 Available @code{opaque-prosody-configuration} fields are:
26003 @deftypevr {@code{opaque-prosody-configuration} parameter} package prosody
26004 The prosody package.
26007 @deftypevr {@code{opaque-prosody-configuration} parameter} string prosody.cfg.lua
26008 The contents of the @code{prosody.cfg.lua} to use.
26011 For example, if your @code{prosody.cfg.lua} is just the empty
26012 string, you could instantiate a prosody service like this:
26015 (service prosody-service-type
26016 (opaque-prosody-configuration
26017 (prosody.cfg.lua "")))
26020 @c end of Prosody auto-generated documentation
26022 @subsubheading BitlBee Service
26024 @cindex IRC (Internet Relay Chat)
26025 @cindex IRC gateway
26026 @url{https://bitlbee.org,BitlBee} is a gateway that provides an IRC
26027 interface to a variety of messaging protocols such as XMPP.
26029 @defvr {Scheme Variable} bitlbee-service-type
26030 This is the service type for the @url{https://bitlbee.org,BitlBee} IRC
26031 gateway daemon. Its value is a @code{bitlbee-configuration} (see
26034 To have BitlBee listen on port 6667 on localhost, add this line to your
26038 (service bitlbee-service-type)
26042 @deftp {Data Type} bitlbee-configuration
26043 This is the configuration for BitlBee, with the following fields:
26046 @item @code{interface} (default: @code{"127.0.0.1"})
26047 @itemx @code{port} (default: @code{6667})
26048 Listen on the network interface corresponding to the IP address
26049 specified in @var{interface}, on @var{port}.
26051 When @var{interface} is @code{127.0.0.1}, only local clients can
26052 connect; when it is @code{0.0.0.0}, connections can come from any
26053 networking interface.
26055 @item @code{bitlbee} (default: @code{bitlbee})
26056 The BitlBee package to use.
26058 @item @code{plugins} (default: @code{'()})
26059 List of plugin packages to use---e.g., @code{bitlbee-discord}.
26061 @item @code{extra-settings} (default: @code{""})
26062 Configuration snippet added as-is to the BitlBee configuration file.
26066 @subsubheading Quassel Service
26068 @cindex IRC (Internet Relay Chat)
26069 @url{https://quassel-irc.org/,Quassel} is a distributed IRC client,
26070 meaning that one or more clients can attach to and detach from the
26073 @defvr {Scheme Variable} quassel-service-type
26074 This is the service type for the @url{https://quassel-irc.org/,Quassel}
26075 IRC backend daemon. Its value is a @code{quassel-configuration}
26079 @deftp {Data Type} quassel-configuration
26080 This is the configuration for Quassel, with the following fields:
26083 @item @code{quassel} (default: @code{quassel})
26084 The Quassel package to use.
26086 @item @code{interface} (default: @code{"::,0.0.0.0"})
26087 @item @code{port} (default: @code{4242})
26088 Listen on the network interface(s) corresponding to the IPv4 or IPv6
26089 interfaces specified in the comma delimited @var{interface}, on
26092 @item @code{loglevel} (default: @code{"Info"})
26093 The level of logging desired. Accepted values are Debug, Info, Warning
26098 @node Telephony Services
26099 @subsection Telephony Services
26101 @cindex telephony, services
26102 The @code{(gnu services telephony)} module contains Guix service
26103 definitions for telephony services. Currently it provides the following
26106 @subsubheading Jami
26108 @cindex jami, service
26110 This section describes how to configure a Jami server that can be used
26111 to host video (or audio) conferences, among other uses. The following
26112 example demonstrates how to specify Jami account archives (backups) to
26113 be provisioned automatically:
26116 (service jami-service-type
26117 (jami-configuration
26119 (list (jami-account
26120 (archive "/etc/jami/unencrypted-account-1.gz"))
26122 (archive "/etc/jami/unencrypted-account-2.gz"))))))
26125 When the accounts field is specified, the Jami account files of the
26126 service found under @file{/var/lib/jami} are recreated every time the
26129 Jami accounts and their corresponding backup archives can be generated
26130 using the @code{jami} or @code{jami-gnome} Jami clients. The accounts
26131 should not be password-protected, but it is wise to ensure their files
26132 are only readable by @samp{root}.
26134 The next example shows how to declare that only some contacts should be
26135 allowed to communicate with a given account:
26138 (service jami-service-type
26139 (jami-configuration
26141 (list (jami-account
26142 (archive "/etc/jami/unencrypted-account-1.gz")
26143 (peer-discovery? #t)
26144 (rendezvous-point? #t)
26146 '("1dbcb0f5f37324228235564b79f2b9737e9a008f"
26147 "2dbcb0f5f37324228235564b79f2b9737e9a008f")))))))
26150 In this mode, only the declared @code{allowed-contacts} can initiate
26151 communication with the Jami account. This can be used, for example,
26152 with rendezvous point accounts to create a private video conferencing
26155 To put the system administrator in full control of the conferences
26156 hosted on their system, the Jami service supports the following actions:
26159 # herd doc jami list-actions
26161 list-account-details
26162 list-banned-contacts
26171 The above actions aim to provide the most valuable actions for
26172 moderation purposes, not to cover the whole Jami API. Users wanting to
26173 interact with the Jami daemon from Guile may be interested in
26174 experimenting with the @code{(gnu build jami-service)} module, which
26175 powers the above Shepherd actions.
26177 @c TODO: This should be auto-generated from the doc already defined on
26178 @c the shepherd-actions themselves in (gnu services telephony).
26179 The @code{add-moderator} and @code{ban-contact} actions accept a contact
26180 @emph{fingerprint} (40 characters long hash) as first argument and an
26181 account fingerprint or username as second argument:
26184 # herd add-moderator jami 1dbcb0f5f37324228235564b79f2b9737e9a008f \
26185 f3345f2775ddfe07a4b0d95daea111d15fbc1199
26187 # herd list-moderators jami
26188 Moderators for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
26189 - 1dbcb0f5f37324228235564b79f2b9737e9a008f
26193 In the case of @code{ban-contact}, the second username argument is
26194 optional; when omitted, the account is banned from all Jami accounts:
26197 # herd ban-contact jami 1dbcb0f5f37324228235564b79f2b9737e9a008f
26199 # herd list-banned-contacts jami
26200 Banned contacts for account f3345f2775ddfe07a4b0d95daea111d15fbc1199:
26201 - 1dbcb0f5f37324228235564b79f2b9737e9a008f
26205 Banned contacts are also stripped from their moderation privileges.
26207 The @code{disable-account} action allows to completely disconnect an
26208 account from the network, making it unreachable, while
26209 @code{enable-account} does the inverse. They accept a single account
26210 username or fingerprint as first argument:
26213 # herd disable-account jami f3345f2775ddfe07a4b0d95daea111d15fbc1199
26215 # herd list-accounts jami
26216 The following Jami accounts are available:
26217 - f3345f2775ddfe07a4b0d95daea111d15fbc1199 (dummy) [disabled]
26221 The @code{list-account-details} action prints the detailed parameters of
26222 each accounts in the Recutils format, which means the @command{recsel}
26223 command can be used to select accounts of interest (@pxref{Selection
26224 Expressions,,,recutils, GNU recutils manual}). Note that period
26225 characters (@samp{.}) found in the account parameter keys are mapped to
26226 underscores (@samp{_}) in the output, to meet the requirements of the
26227 Recutils format. The following example shows how to print the account
26228 fingerprints for all accounts operating in the rendezvous point mode:
26231 # herd list-account-details jami | \
26232 recsel -p Account.username -e 'Account.rendezVous ~ "true"'
26233 Account_username: f3345f2775ddfe07a4b0d95daea111d15fbc1199
26236 The remaining actions should be self-explanatory.
26238 The complete set of available configuration options is detailed below.
26240 @c TODO: Ideally, the following fragments would be auto-generated at
26241 @c build time, so that they needn't be manually duplicated.
26242 @c Auto-generated via (configuration->documentation 'jami-configuration)
26243 @deftp {Data Type} jami-configuration
26244 Available @code{jami-configuration} fields are:
26247 @item @code{libjami} (default: @code{libjami}) (type: package)
26248 The Jami daemon package to use.
26250 @item @code{dbus} (default: @code{dbus-for-jami}) (type: package)
26251 The D-Bus package to use to start the required D-Bus session.
26253 @item @code{nss-certs} (default: @code{nss-certs}) (type: package)
26254 The nss-certs package to use to provide TLS certificates.
26256 @item @code{enable-logging?} (default: @code{#t}) (type: boolean)
26257 Whether to enable logging to syslog.
26259 @item @code{debug?} (default: @code{#f}) (type: boolean)
26260 Whether to enable debug level messages.
26262 @item @code{auto-answer?} (default: @code{#f}) (type: boolean)
26263 Whether to force automatic answer to incoming calls.
26265 @item @code{accounts} (type: maybe-jami-account-list)
26266 A list of Jami accounts to be (re-)provisioned every time the Jami
26267 daemon service starts. When providing this field, the account
26268 directories under @file{/var/lib/jami/} are recreated every time the
26269 service starts, ensuring a consistent state.
26275 @c Auto-generated via (configuration->documentation 'jami-account)
26276 @deftp {Data Type} jami-account
26277 Available @code{jami-account} fields are:
26280 @item @code{archive} (type: string-or-computed-file)
26281 The account archive (backup) file name of the account. This is used to
26282 provision the account when the service starts. The account archive
26283 should @emph{not} be encrypted. It is highly recommended to make it
26284 readable only to the @samp{root} user (i.e., not in the store), to guard
26285 against leaking the secret key material of the Jami account it contains.
26287 @item @code{allowed-contacts} (type: maybe-account-fingerprint-list)
26288 The list of allowed contacts for the account, entered as their 40
26289 characters long fingerprint. Messages or calls from accounts not in
26290 that list will be rejected. When left specified, the configuration of
26291 the account archive is used as-is with respect to contacts and public
26292 inbound calls/messaging allowance, which typically defaults to allow any
26293 contact to communicate with the account.
26295 @item @code{moderators} (type: maybe-account-fingerprint-list)
26296 The list of contacts that should have moderation privileges (to ban,
26297 mute, etc. other users) in rendezvous conferences, entered as their 40
26298 characters long fingerprint. When left unspecified, the configuration
26299 of the account archive is used as-is with respect to moderation, which
26300 typically defaults to allow anyone to moderate.
26302 @item @code{rendezvous-point?} (type: maybe-boolean)
26303 Whether the account should operate in the rendezvous mode. In this
26304 mode, all the incoming audio/video calls are mixed into a conference.
26305 When left unspecified, the value from the account archive prevails.
26307 @item @code{peer-discovery?} (type: maybe-boolean)
26308 Whether peer discovery should be enabled. Peer discovery is used to
26309 discover other OpenDHT nodes on the local network, which can be useful
26310 to maintain communication between devices on such network even when the
26311 connection to the the Internet has been lost. When left unspecified,
26312 the value from the account archive prevails.
26314 @item @code{bootstrap-hostnames} (type: maybe-string-list)
26315 A list of hostnames or IPs pointing to OpenDHT nodes, that should be
26316 used to initially join the OpenDHT network. When left unspecified, the
26317 value from the account archive prevails.
26319 @item @code{name-server-uri} (type: maybe-string)
26320 The URI of the name server to use, that can be used to retrieve the
26321 account fingerprint for a registered username.
26327 @subsubheading Mumble server
26331 @cindex VoIP server
26332 This section describes how to set up and run a
26333 @uref{https://mumble.info, Mumble} server (formerly known as Murmur).
26335 @deftp {Data Type} mumble-server-configuration
26336 The service type for the Mumble server. An example configuration can
26340 (service mumble-server-service-type
26341 (mumble-server-configuration
26343 "Welcome to this Mumble server running on Guix!")
26344 (cert-required? #t) ;disallow text password logins
26345 (ssl-cert "/etc/letsencrypt/live/mumble.example.com/fullchain.pem")
26346 (ssl-key "/etc/letsencrypt/live/mumble.example.com/privkey.pem")))
26349 After reconfiguring your system, you can manually set the mumble-server
26351 password with the command that is printed during the activation phase.
26353 It is recommended to register a normal Mumble user account
26354 and grant it admin or moderator rights.
26355 You can use the @code{mumble} client to
26356 login as new normal user, register yourself, and log out.
26357 For the next step login with the name @code{SuperUser} use
26358 the @code{SuperUser} password that you set previously,
26359 and grant your newly registered mumble user administrator or moderator
26360 rights and create some channels.
26362 Available @code{mumble-server-configuration} fields are:
26365 @item @code{package} (default: @code{mumble})
26366 Package that contains @code{bin/mumble-server}.
26368 @item @code{user} (default: @code{"mumble-server"})
26369 User who will run the Mumble-Server server.
26371 @item @code{group} (default: @code{"mumble-server"})
26372 Group of the user who will run the mumble-server server.
26374 @item @code{port} (default: @code{64738})
26375 Port on which the server will listen.
26377 @item @code{welcome-text} (default: @code{""})
26378 Welcome text sent to clients when they connect.
26380 @item @code{server-password} (default: @code{""})
26381 Password the clients have to enter in order to connect.
26383 @item @code{max-users} (default: @code{100})
26384 Maximum of users that can be connected to the server at once.
26386 @item @code{max-user-bandwidth} (default: @code{#f})
26387 Maximum voice traffic a user can send per second.
26389 @item @code{database-file} (default: @code{"/var/lib/mumble-server/db.sqlite"})
26390 File name of the sqlite database.
26391 The service's user will become the owner of the directory.
26393 @item @code{log-file} (default: @code{"/var/log/mumble-server/mumble-server.log"})
26394 File name of the log file.
26395 The service's user will become the owner of the directory.
26397 @item @code{autoban-attempts} (default: @code{10})
26398 Maximum number of logins a user can make in @code{autoban-timeframe}
26399 without getting auto banned for @code{autoban-time}.
26401 @item @code{autoban-timeframe} (default: @code{120})
26402 Timeframe for autoban in seconds.
26404 @item @code{autoban-time} (default: @code{300})
26405 Amount of time in seconds for which a client gets banned
26406 when violating the autoban limits.
26408 @item @code{opus-threshold} (default: @code{100})
26409 Percentage of clients that need to support opus
26410 before switching over to opus audio codec.
26412 @item @code{channel-nesting-limit} (default: @code{10})
26413 How deep channels can be nested at maximum.
26415 @item @code{channelname-regex} (default: @code{#f})
26416 A string in form of a Qt regular expression that channel names must conform to.
26418 @item @code{username-regex} (default: @code{#f})
26419 A string in form of a Qt regular expression that user names must conform to.
26421 @item @code{text-message-length} (default: @code{5000})
26422 Maximum size in bytes that a user can send in one text chat message.
26424 @item @code{image-message-length} (default: @code{(* 128 1024)})
26425 Maximum size in bytes that a user can send in one image message.
26427 @item @code{cert-required?} (default: @code{#f})
26428 If it is set to @code{#t} clients that use weak password authentication
26429 will not be accepted. Users must have completed the certificate wizard to join.
26431 @item @code{remember-channel?} (default: @code{#f})
26432 Should mumble-server remember the last channel each user was in when
26433 they disconnected and put them into the remembered channel when they
26436 @item @code{allow-html?} (default: @code{#f})
26437 Should html be allowed in text messages, user comments, and channel descriptions.
26439 @item @code{allow-ping?} (default: @code{#f})
26440 Setting to true exposes the current user count, the maximum user count, and
26441 the server's maximum bandwidth per client to unauthenticated users. In the
26442 Mumble client, this information is shown in the Connect dialog.
26444 Disabling this setting will prevent public listing of the server.
26446 @item @code{bonjour?} (default: @code{#f})
26447 Should the server advertise itself in the local network through the bonjour protocol.
26449 @item @code{send-version?} (default: @code{#f})
26450 Should the mumble-server server version be exposed in ping requests.
26452 @item @code{log-days} (default: @code{31})
26453 Mumble also stores logs in the database, which are accessible via RPC.
26454 The default is 31 days of months, but you can set this setting to 0 to keep logs forever,
26455 or -1 to disable logging to the database.
26457 @item @code{obfuscate-ips?} (default: @code{#t})
26458 Should logged ips be obfuscated to protect the privacy of users.
26460 @item @code{ssl-cert} (default: @code{#f})
26461 File name of the SSL/TLS certificate used for encrypted connections.
26464 (ssl-cert "/etc/letsencrypt/live/example.com/fullchain.pem")
26466 @item @code{ssl-key} (default: @code{#f})
26467 Filepath to the ssl private key used for encrypted connections.
26469 (ssl-key "/etc/letsencrypt/live/example.com/privkey.pem")
26472 @item @code{ssl-dh-params} (default: @code{#f})
26473 File name of a PEM-encoded file with Diffie-Hellman parameters
26474 for the SSL/TLS encryption. Alternatively you set it to
26475 @code{"@@ffdhe2048"}, @code{"@@ffdhe3072"}, @code{"@@ffdhe4096"}, @code{"@@ffdhe6144"}
26476 or @code{"@@ffdhe8192"} to use bundled parameters from RFC 7919.
26478 @item @code{ssl-ciphers} (default: @code{#f})
26479 The @code{ssl-ciphers} option chooses the cipher suites to make available for use
26482 This option is specified using
26483 @uref{https://www.openssl.org/docs/apps/ciphers.html#CIPHER-LIST-FORMAT,
26484 OpenSSL cipher list notation}.
26486 It is recommended that you try your cipher string using
26487 'openssl ciphers <string>' before setting it here, to get a feel for
26488 which cipher suites you will get.
26489 After setting this option, it is recommend that you inspect your Mumble
26490 server log to ensure that Mumble is using the cipher suites that you
26494 Changing this option may impact the backwards compatibility of your
26495 Mumble-Server server, and can remove the ability for older Mumble clients to be able to connect to it.
26498 @item @code{public-registration} (default: @code{#f})
26499 Must be a @code{<mumble-server-public-registration-configuration>}
26500 record or @code{#f}.
26502 You can optionally register your server in the public server list that the
26503 @code{mumble} client shows on startup.
26504 You cannot register your server if you have set a @code{server-password},
26505 or set @code{allow-ping} to @code{#f}.
26507 It might take a few hours until it shows up in the public list.
26509 @item @code{file} (default: @code{#f})
26510 Optional alternative override for this configuration.
26514 @deftp {Data Type} mumble-server-public-registration-configuration
26515 Configuration for public registration of a mumble-server service.
26519 This is a display name for your server. Not to be confused with the hostname.
26521 @item @code{password}
26522 A password to identify your registration.
26523 Subsequent updates will need the same password. Don't lose your password.
26526 This should be a @code{http://} or @code{https://} link to your web
26529 @item @code{hostname} (default: @code{#f})
26530 By default your server will be listed by its IP address.
26531 If it is set your server will be linked by this host name instead.
26535 @quotation Deprecation notice
26536 Due to historical reasons, all of the above @code{mumble-server-}
26537 procedures are also exported with the @code{murmur-} prefix.
26538 It is recommended that you switch to using @code{mumble-server-}
26542 @node File-Sharing Services
26543 @subsection File-Sharing Services
26545 The @code{(gnu services file-sharing)} module provides services that
26546 assist with transferring files over peer-to-peer file-sharing networks.
26548 @subsubheading Transmission Daemon Service
26550 @uref{https://transmissionbt.com/, Transmission} is a flexible
26551 BitTorrent client that offers a variety of graphical and command-line
26552 interfaces. A @code{transmission-daemon-service-type} service provides
26553 Transmission's headless variant, @command{transmission-daemon}, as a
26554 system service, allowing users to share files via BitTorrent even when
26555 they are not logged in.
26557 @deffn {Scheme Variable} transmission-daemon-service-type
26558 The service type for the Transmission Daemon BitTorrent client. Its
26559 value must be a @code{transmission-daemon-configuration} object as in
26563 (service transmission-daemon-service-type
26564 (transmission-daemon-configuration
26565 ;; Restrict access to the RPC ("control") interface
26566 (rpc-authentication-required? #t)
26567 (rpc-username "transmission")
26569 (transmission-password-hash
26570 "transmission" ; desired password
26571 "uKd1uMs9")) ; arbitrary salt value
26573 ;; Accept requests from this and other hosts on the
26575 (rpc-whitelist-enabled? #t)
26576 (rpc-whitelist '("::1" "127.0.0.1" "192.168.0.*"))
26578 ;; Limit bandwidth use during work hours
26579 (alt-speed-down (* 1024 2)) ; 2 MB/s
26580 (alt-speed-up 512) ; 512 kB/s
26582 (alt-speed-time-enabled? #t)
26583 (alt-speed-time-day 'weekdays)
26584 (alt-speed-time-begin
26585 (+ (* 60 8) 30)) ; 8:30 am
26586 (alt-speed-time-end
26587 (+ (* 60 (+ 12 5)) 30)))) ; 5:30 pm
26591 Once the service is started, users can interact with the daemon through
26592 its Web interface (at @code{http://localhost:9091/}) or by using the
26593 @command{transmission-remote} command-line tool, available in the
26594 @code{transmission} package. (Emacs users may want to also consider the
26595 @code{emacs-transmission} package.) Both communicate with the daemon
26596 through its remote procedure call (RPC) interface, which by default is
26597 available to all users on the system; you may wish to change this by
26598 assigning values to the @code{rpc-authentication-required?},
26599 @code{rpc-username} and @code{rpc-password} settings, as shown in the
26600 example above and documented further below.
26602 The value for @code{rpc-password} must be a password hash of the type
26603 generated and used by Transmission clients. This can be copied verbatim
26604 from an existing @file{settings.json} file, if another Transmission
26605 client is already being used. Otherwise, the
26606 @code{transmission-password-hash} and @code{transmission-random-salt}
26607 procedures provided by this module can be used to obtain a suitable hash
26610 @deffn {Scheme Procedure} transmission-password-hash @var{password} @var{salt}
26611 Returns a string containing the result of hashing @var{password}
26612 together with @var{salt}, in the format recognized by Transmission
26613 clients for their @code{rpc-password} configuration setting.
26615 @var{salt} must be an eight-character string. The
26616 @code{transmission-random-salt} procedure can be used to generate a
26617 suitable salt value at random.
26620 @deffn {Scheme Procedure} transmission-random-salt
26621 Returns a string containing a random, eight-character salt value of the
26622 type generated and used by Transmission clients, suitable for passing to
26623 the @code{transmission-password-hash} procedure.
26626 These procedures are accessible from within a Guile REPL started with
26627 the @command{guix repl} command (@pxref{Invoking guix repl}). This is
26628 useful for obtaining a random salt value to provide as the second
26629 parameter to `transmission-password-hash`, as in this example session:
26633 scheme@@(guix-user)> ,use (gnu services file-sharing)
26634 scheme@@(guix-user)> (transmission-random-salt)
26638 Alternatively, a complete password hash can generated in a single step:
26641 scheme@@(guix-user)> (transmission-password-hash "transmission"
26642 (transmission-random-salt))
26643 $2 = "@{c8bbc6d1740cd8dc819a6e25563b67812c1c19c9VtFPfdsX"
26646 The resulting string can be used as-is for the value of
26647 @code{rpc-password}, allowing the password to be kept hidden even in the
26648 operating-system configuration.
26650 Torrent files downloaded by the daemon are directly accessible only to
26651 users in the ``transmission'' user group, who receive read-only access
26652 to the directory specified by the @code{download-dir} configuration
26653 setting (and also the directory specified by @code{incomplete-dir}, if
26654 @code{incomplete-dir-enabled?} is @code{#t}). Downloaded files can be
26655 moved to another directory or deleted altogether using
26656 @command{transmission-remote} with its @code{--move} and
26657 @code{--remove-and-delete} options.
26659 If the @code{watch-dir-enabled?} setting is set to @code{#t}, users in
26660 the ``transmission'' group are able also to place @file{.torrent} files
26661 in the directory specified by @code{watch-dir} to have the corresponding
26662 torrents added by the daemon. (The @code{trash-original-torrent-files?}
26663 setting controls whether the daemon deletes these files after processing
26666 Some of the daemon's configuration settings can be changed temporarily
26667 by @command{transmission-remote} and similar tools. To undo these
26668 changes, use the service's @code{reload} action to have the daemon
26669 reload its settings from disk:
26672 # herd reload transmission-daemon
26675 The full set of available configuration settings is defined by the
26676 @code{transmission-daemon-configuration} data type.
26678 @deftp {Data Type} transmission-daemon-configuration
26679 The data type representing configuration settings for Transmission
26680 Daemon. These correspond directly to the settings recognized by
26681 Transmission clients in their @file{settings.json} file.
26684 @c The following documentation was initially generated by
26685 @c (generate-transmission-daemon-documentation) in (gnu services
26686 @c file-sharing). Manually maintained documentation is better, so we
26687 @c shouldn't hesitate to edit below as needed. However if the change
26688 @c you want to make to this documentation can be done in an automated
26689 @c way, it's probably easier to change (generate-documentation) than to
26690 @c make it below and have to deal with the churn as Transmission Daemon
26693 @c %start of fragment
26695 Available @code{transmission-daemon-configuration} fields are:
26697 @deftypevr {@code{transmission-daemon-configuration} parameter} package transmission
26698 The Transmission package to use.
26702 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer stop-wait-period
26703 The period, in seconds, to wait when stopping the service for
26704 @command{transmission-daemon} to exit before killing its process. This
26705 allows the daemon time to complete its housekeeping and send a final
26706 update to trackers as it shuts down. On slow hosts, or hosts with a
26707 slow network connection, this value may need to be increased.
26709 Defaults to @samp{10}.
26713 @deftypevr {@code{transmission-daemon-configuration} parameter} string download-dir
26714 The directory to which torrent files are downloaded.
26716 Defaults to @samp{"/var/lib/transmission-daemon/downloads"}.
26720 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean incomplete-dir-enabled?
26721 If @code{#t}, files will be held in @code{incomplete-dir} while their
26722 torrent is being downloaded, then moved to @code{download-dir} once the
26723 torrent is complete. Otherwise, files for all torrents (including those
26724 still being downloaded) will be placed in @code{download-dir}.
26726 Defaults to @samp{#f}.
26730 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string incomplete-dir
26731 The directory in which files from incompletely downloaded torrents will
26732 be held when @code{incomplete-dir-enabled?} is @code{#t}.
26734 Defaults to @samp{disabled}.
26738 @deftypevr {@code{transmission-daemon-configuration} parameter} umask umask
26739 The file mode creation mask used for downloaded files. (See the
26740 @command{umask} man page for more information.)
26742 Defaults to @samp{18}.
26746 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rename-partial-files?
26747 When @code{#t}, ``.part'' is appended to the name of partially
26750 Defaults to @samp{#t}.
26754 @deftypevr {@code{transmission-daemon-configuration} parameter} preallocation-mode preallocation
26755 The mode by which space should be preallocated for downloaded files, one
26756 of @code{none}, @code{fast} (or @code{sparse}) and @code{full}.
26757 Specifying @code{full} will minimize disk fragmentation at a cost to
26758 file-creation speed.
26760 Defaults to @samp{fast}.
26764 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean watch-dir-enabled?
26765 If @code{#t}, the directory specified by @code{watch-dir} will be
26766 watched for new @file{.torrent} files and the torrents they describe
26767 added automatically (and the original files removed, if
26768 @code{trash-original-torrent-files?} is @code{#t}).
26770 Defaults to @samp{#f}.
26774 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string watch-dir
26775 The directory to be watched for @file{.torrent} files indicating new
26776 torrents to be added, when @code{watch-dir-enabled} is @code{#t}.
26778 Defaults to @samp{disabled}.
26782 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean trash-original-torrent-files?
26783 When @code{#t}, @file{.torrent} files will be deleted from the watch
26784 directory once their torrent has been added (see
26785 @code{watch-directory-enabled?}).
26787 Defaults to @samp{#f}.
26791 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-down-enabled?
26792 When @code{#t}, the daemon's download speed will be limited to the rate
26793 specified by @code{speed-limit-down}.
26795 Defaults to @samp{#f}.
26799 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-down
26800 The default global-maximum download speed, in kilobytes per second.
26802 Defaults to @samp{100}.
26806 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean speed-limit-up-enabled?
26807 When @code{#t}, the daemon's upload speed will be limited to the rate
26808 specified by @code{speed-limit-up}.
26810 Defaults to @samp{#f}.
26814 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer speed-limit-up
26815 The default global-maximum upload speed, in kilobytes per second.
26817 Defaults to @samp{100}.
26821 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-enabled?
26822 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
26823 @code{alt-speed-up} are used (in place of @code{speed-limit-down} and
26824 @code{speed-limit-up}, if they are enabled) to constrain the daemon's
26825 bandwidth usage. This can be scheduled to occur automatically at
26826 certain times during the week; see @code{alt-speed-time-enabled?}.
26828 Defaults to @samp{#f}.
26832 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-down
26833 The alternate global-maximum download speed, in kilobytes per second.
26835 Defaults to @samp{50}.
26839 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-up
26840 The alternate global-maximum upload speed, in kilobytes per second.
26842 Defaults to @samp{50}.
26846 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean alt-speed-time-enabled?
26847 When @code{#t}, the alternate speed limits @code{alt-speed-down} and
26848 @code{alt-speed-up} will be enabled automatically during the periods
26849 specified by @code{alt-speed-time-day}, @code{alt-speed-time-begin} and
26850 @code{alt-time-speed-end}.
26852 Defaults to @samp{#f}.
26856 @deftypevr {@code{transmission-daemon-configuration} parameter} day-list alt-speed-time-day
26857 The days of the week on which the alternate-speed schedule should be
26858 used, specified either as a list of days (@code{sunday}, @code{monday},
26859 and so on) or using one of the symbols @code{weekdays}, @code{weekends}
26862 Defaults to @samp{all}.
26866 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-begin
26867 The time of day at which to enable the alternate speed limits, expressed
26868 as a number of minutes since midnight.
26870 Defaults to @samp{540}.
26874 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer alt-speed-time-end
26875 The time of day at which to disable the alternate speed limits,
26876 expressed as a number of minutes since midnight.
26878 Defaults to @samp{1020}.
26882 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv4
26883 The IP address at which to listen for peer connections, or ``0.0.0.0''
26884 to listen at all available IP addresses.
26886 Defaults to @samp{"0.0.0.0"}.
26890 @deftypevr {@code{transmission-daemon-configuration} parameter} string bind-address-ipv6
26891 The IPv6 address at which to listen for peer connections, or ``::'' to
26892 listen at all available IPv6 addresses.
26894 Defaults to @samp{"::"}.
26898 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean peer-port-random-on-start?
26899 If @code{#t}, when the daemon starts it will select a port at random on
26900 which to listen for peer connections, from the range specified
26901 (inclusively) by @code{peer-port-random-low} and
26902 @code{peer-port-random-high}. Otherwise, it listens on the port
26903 specified by @code{peer-port}.
26905 Defaults to @samp{#f}.
26909 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-low
26910 The lowest selectable port number when @code{peer-port-random-on-start?}
26913 Defaults to @samp{49152}.
26917 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port-random-high
26918 The highest selectable port number when @code{peer-port-random-on-start}
26921 Defaults to @samp{65535}.
26925 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number peer-port
26926 The port on which to listen for peer connections when
26927 @code{peer-port-random-on-start?} is @code{#f}.
26929 Defaults to @samp{51413}.
26933 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean port-forwarding-enabled?
26934 If @code{#t}, the daemon will attempt to configure port-forwarding on an
26935 upstream gateway automatically using @acronym{UPnP} and
26938 Defaults to @samp{#t}.
26942 @deftypevr {@code{transmission-daemon-configuration} parameter} encryption-mode encryption
26943 The encryption preference for peer connections, one of
26944 @code{prefer-unencrypted-connections},
26945 @code{prefer-encrypted-connections} or
26946 @code{require-encrypted-connections}.
26948 Defaults to @samp{prefer-encrypted-connections}.
26952 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string peer-congestion-algorithm
26953 The TCP congestion-control algorithm to use for peer connections,
26954 specified using a string recognized by the operating system in calls to
26955 @code{setsockopt}. When left unspecified, the operating-system default
26958 Note that on GNU/Linux systems, the kernel must be configured to allow
26959 processes to use a congestion-control algorithm not in the default set;
26960 otherwise, it will deny these requests with ``Operation not permitted''.
26961 To see which algorithms are available on your system and which are
26962 currently permitted for use, look at the contents of the files
26963 @file{tcp_available_congestion_control} and
26964 @file{tcp_allowed_congestion_control} in the @file{/proc/sys/net/ipv4}
26967 As an example, to have Transmission Daemon use
26968 @uref{http://www-ece.rice.edu/networks/TCP-LP/,the TCP Low Priority
26969 congestion-control algorithm}, you'll need to modify your kernel
26970 configuration to build in support for the algorithm, then update your
26971 operating-system configuration to allow its use by adding a
26972 @code{sysctl-service-type} service (or updating the existing one's
26973 configuration) with lines like the following:
26976 (service sysctl-service-type
26977 (sysctl-configuration
26979 ("net.ipv4.tcp_allowed_congestion_control" .
26980 "reno cubic lp"))))
26983 The Transmission Daemon configuration can then be updated with
26986 (peer-congestion-algorithm "lp")
26989 and the system reconfigured to have the changes take effect.
26991 Defaults to @samp{disabled}.
26995 @deftypevr {@code{transmission-daemon-configuration} parameter} tcp-type-of-service peer-socket-tos
26996 The type of service to request in outgoing @acronym{TCP} packets, one of
26997 @code{default}, @code{low-cost}, @code{throughput}, @code{low-delay} and
26998 @code{reliability}.
27000 Defaults to @samp{default}.
27004 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-global
27005 The global limit on the number of connected peers.
27007 Defaults to @samp{200}.
27011 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-limit-per-torrent
27012 The per-torrent limit on the number of connected peers.
27014 Defaults to @samp{50}.
27018 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer upload-slots-per-torrent
27019 The maximum number of peers to which the daemon will upload data
27020 simultaneously for each torrent.
27022 Defaults to @samp{14}.
27026 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer peer-id-ttl-hours
27027 The maximum lifespan, in hours, of the peer ID associated with each
27028 public torrent before it is regenerated.
27030 Defaults to @samp{6}.
27034 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean blocklist-enabled?
27035 When @code{#t}, the daemon will ignore peers mentioned in the blocklist
27036 it has most recently downloaded from @code{blocklist-url}.
27038 Defaults to @samp{#f}.
27042 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string blocklist-url
27043 The URL of a peer blocklist (in @acronym{P2P}-plaintext or eMule
27044 @file{.dat} format) to be periodically downloaded and applied when
27045 @code{blocklist-enabled?} is @code{#t}.
27047 Defaults to @samp{disabled}.
27051 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean download-queue-enabled?
27052 If @code{#t}, the daemon will be limited to downloading at most
27053 @code{download-queue-size} non-stalled torrents simultaneously.
27055 Defaults to @samp{#t}.
27059 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer download-queue-size
27060 The size of the daemon's download queue, which limits the number of
27061 non-stalled torrents it will download at any one time when
27062 @code{download-queue-enabled?} is @code{#t}.
27064 Defaults to @samp{5}.
27068 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean seed-queue-enabled?
27069 If @code{#t}, the daemon will be limited to seeding at most
27070 @code{seed-queue-size} non-stalled torrents simultaneously.
27072 Defaults to @samp{#f}.
27076 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer seed-queue-size
27077 The size of the daemon's seed queue, which limits the number of
27078 non-stalled torrents it will seed at any one time when
27079 @code{seed-queue-enabled?} is @code{#t}.
27081 Defaults to @samp{10}.
27085 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean queue-stalled-enabled?
27086 When @code{#t}, the daemon will consider torrents for which it has not
27087 shared data in the past @code{queue-stalled-minutes} minutes to be
27088 stalled and not count them against its @code{download-queue-size} and
27089 @code{seed-queue-size} limits.
27091 Defaults to @samp{#t}.
27095 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer queue-stalled-minutes
27096 The maximum period, in minutes, a torrent may be idle before it is
27097 considered to be stalled, when @code{queue-stalled-enabled?} is
27100 Defaults to @samp{30}.
27104 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean ratio-limit-enabled?
27105 When @code{#t}, a torrent being seeded will automatically be paused once
27106 it reaches the ratio specified by @code{ratio-limit}.
27108 Defaults to @samp{#f}.
27112 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-rational ratio-limit
27113 The ratio at which a torrent being seeded will be paused, when
27114 @code{ratio-limit-enabled?} is @code{#t}.
27116 Defaults to @samp{2.0}.
27120 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean idle-seeding-limit-enabled?
27121 When @code{#t}, a torrent being seeded will automatically be paused once
27122 it has been idle for @code{idle-seeding-limit} minutes.
27124 Defaults to @samp{#f}.
27128 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer idle-seeding-limit
27129 The maximum period, in minutes, a torrent being seeded may be idle
27130 before it is paused, when @code{idle-seeding-limit-enabled?} is
27133 Defaults to @samp{30}.
27137 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean dht-enabled?
27138 Enable @uref{http://bittorrent.org/beps/bep_0005.html,the distributed
27139 hash table (@acronym{DHT}) protocol}, which supports the use of
27140 trackerless torrents.
27142 Defaults to @samp{#t}.
27146 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean lpd-enabled?
27147 Enable @uref{https://en.wikipedia.org/wiki/Local_Peer_Discovery,local
27148 peer discovery} (@acronym{LPD}), which allows the discovery of peers on
27149 the local network and may reduce the amount of data sent over the public
27152 Defaults to @samp{#f}.
27156 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean pex-enabled?
27157 Enable @uref{https://en.wikipedia.org/wiki/Peer_exchange,peer exchange}
27158 (@acronym{PEX}), which reduces the daemon's reliance on external
27159 trackers and may improve its performance.
27161 Defaults to @samp{#t}.
27165 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean utp-enabled?
27166 Enable @uref{http://bittorrent.org/beps/bep_0029.html,the micro
27167 transport protocol} (@acronym{uTP}), which aims to reduce the impact of
27168 BitTorrent traffic on other users of the local network while maintaining
27169 full utilization of the available bandwidth.
27171 Defaults to @samp{#t}.
27175 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-enabled?
27176 If @code{#t}, enable the remote procedure call (@acronym{RPC})
27177 interface, which allows remote control of the daemon via its Web
27178 interface, the @command{transmission-remote} command-line client, and
27181 Defaults to @samp{#t}.
27185 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-bind-address
27186 The IP address at which to listen for @acronym{RPC} connections, or
27187 ``0.0.0.0'' to listen at all available IP addresses.
27189 Defaults to @samp{"0.0.0.0"}.
27193 @deftypevr {@code{transmission-daemon-configuration} parameter} port-number rpc-port
27194 The port on which to listen for @acronym{RPC} connections.
27196 Defaults to @samp{9091}.
27200 @deftypevr {@code{transmission-daemon-configuration} parameter} string rpc-url
27201 The path prefix to use in the @acronym{RPC}-endpoint @acronym{URL}.
27203 Defaults to @samp{"/transmission/"}.
27207 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-authentication-required?
27208 When @code{#t}, clients must authenticate (see @code{rpc-username} and
27209 @code{rpc-password}) when using the @acronym{RPC} interface. Note this
27210 has the side effect of disabling host-name whitelisting (see
27211 @code{rpc-host-whitelist-enabled?}.
27213 Defaults to @samp{#f}.
27217 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-string rpc-username
27218 The username required by clients to access the @acronym{RPC} interface
27219 when @code{rpc-authentication-required?} is @code{#t}.
27221 Defaults to @samp{disabled}.
27225 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-transmission-password-hash rpc-password
27226 The password required by clients to access the @acronym{RPC} interface
27227 when @code{rpc-authentication-required?} is @code{#t}. This must be
27228 specified using a password hash in the format recognized by Transmission
27229 clients, either copied from an existing @file{settings.json} file or
27230 generated using the @code{transmission-password-hash} procedure.
27232 Defaults to @samp{disabled}.
27236 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-whitelist-enabled?
27237 When @code{#t}, @acronym{RPC} requests will be accepted only when they
27238 originate from an address specified in @code{rpc-whitelist}.
27240 Defaults to @samp{#t}.
27244 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-whitelist
27245 The list of IP and IPv6 addresses from which @acronym{RPC} requests will
27246 be accepted when @code{rpc-whitelist-enabled?} is @code{#t}. Wildcards
27247 may be specified using @samp{*}.
27249 Defaults to @samp{("127.0.0.1" "::1")}.
27253 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean rpc-host-whitelist-enabled?
27254 When @code{#t}, @acronym{RPC} requests will be accepted only when they
27255 are addressed to a host named in @code{rpc-host-whitelist}. Note that
27256 requests to ``localhost'' or ``localhost.'', or to a numeric address,
27257 are always accepted regardless of these settings.
27259 Note also this functionality is disabled when
27260 @code{rpc-authentication-required?} is @code{#t}.
27262 Defaults to @samp{#t}.
27266 @deftypevr {@code{transmission-daemon-configuration} parameter} string-list rpc-host-whitelist
27267 The list of host names recognized by the @acronym{RPC} server when
27268 @code{rpc-host-whitelist-enabled?} is @code{#t}.
27270 Defaults to @samp{()}.
27274 @deftypevr {@code{transmission-daemon-configuration} parameter} message-level message-level
27275 The minimum severity level of messages to be logged (to
27276 @file{/var/log/transmission.log}) by the daemon, one of @code{none} (no
27277 logging), @code{error}, @code{info} and @code{debug}.
27279 Defaults to @samp{info}.
27283 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean start-added-torrents?
27284 When @code{#t}, torrents are started as soon as they are added;
27285 otherwise, they are added in ``paused'' state.
27287 Defaults to @samp{#t}.
27291 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean script-torrent-done-enabled?
27292 When @code{#t}, the script specified by
27293 @code{script-torrent-done-filename} will be invoked each time a torrent
27296 Defaults to @samp{#f}.
27300 @deftypevr {@code{transmission-daemon-configuration} parameter} maybe-file-object script-torrent-done-filename
27301 A file name or file-like object specifying a script to run each time a
27302 torrent completes, when @code{script-torrent-done-enabled?} is
27305 Defaults to @samp{disabled}.
27309 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean scrape-paused-torrents-enabled?
27310 When @code{#t}, the daemon will scrape trackers for a torrent even when
27311 the torrent is paused.
27313 Defaults to @samp{#t}.
27317 @deftypevr {@code{transmission-daemon-configuration} parameter} non-negative-integer cache-size-mb
27318 The amount of memory, in megabytes, to allocate for the daemon's
27319 in-memory cache. A larger value may increase performance by reducing
27320 the frequency of disk I/O.
27322 Defaults to @samp{4}.
27326 @deftypevr {@code{transmission-daemon-configuration} parameter} boolean prefetch-enabled?
27327 When @code{#t}, the daemon will try to improve I/O performance by
27328 hinting to the operating system which data is likely to be read next
27329 from disk to satisfy requests from peers.
27331 Defaults to @samp{#t}.
27336 @c %end of fragment
27340 @node Monitoring Services
27341 @subsection Monitoring Services
27343 @subsubheading Tailon Service
27345 @uref{https://tailon.readthedocs.io/, Tailon} is a web application for
27346 viewing and searching log files.
27348 The following example will configure the service with default values.
27349 By default, Tailon can be accessed on port 8080 (@code{http://localhost:8080}).
27352 (service tailon-service-type)
27355 The following example customises more of the Tailon configuration,
27356 adding @command{sed} to the list of allowed commands.
27359 (service tailon-service-type
27360 (tailon-configuration
27362 (tailon-configuration-file
27363 (allowed-commands '("tail" "grep" "awk" "sed"))))))
27367 @deftp {Data Type} tailon-configuration
27368 Data type representing the configuration of Tailon.
27369 This type has the following parameters:
27372 @item @code{config-file} (default: @code{(tailon-configuration-file)})
27373 The configuration file to use for Tailon. This can be set to a
27374 @dfn{tailon-configuration-file} record value, or any gexp
27375 (@pxref{G-Expressions}).
27377 For example, to instead use a local file, the @code{local-file} function
27381 (service tailon-service-type
27382 (tailon-configuration
27383 (config-file (local-file "./my-tailon.conf"))))
27386 @item @code{package} (default: @code{tailon})
27387 The tailon package to use.
27392 @deftp {Data Type} tailon-configuration-file
27393 Data type representing the configuration options for Tailon.
27394 This type has the following parameters:
27397 @item @code{files} (default: @code{(list "/var/log")})
27398 List of files to display. The list can include strings for a single file
27399 or directory, or a list, where the first item is the name of a
27400 subsection, and the remaining items are the files or directories in that
27403 @item @code{bind} (default: @code{"localhost:8080"})
27404 Address and port to which Tailon should bind on.
27406 @item @code{relative-root} (default: @code{#f})
27407 URL path to use for Tailon, set to @code{#f} to not use a path.
27409 @item @code{allow-transfers?} (default: @code{#t})
27410 Allow downloading the log files in the web interface.
27412 @item @code{follow-names?} (default: @code{#t})
27413 Allow tailing of not-yet existent files.
27415 @item @code{tail-lines} (default: @code{200})
27416 Number of lines to read initially from each file.
27418 @item @code{allowed-commands} (default: @code{(list "tail" "grep" "awk")})
27419 Commands to allow running. By default, @code{sed} is disabled.
27421 @item @code{debug?} (default: @code{#f})
27422 Set @code{debug?} to @code{#t} to show debug messages.
27424 @item @code{wrap-lines} (default: @code{#t})
27425 Initial line wrapping state in the web interface. Set to @code{#t} to
27426 initially wrap lines (the default), or to @code{#f} to initially not
27429 @item @code{http-auth} (default: @code{#f})
27430 HTTP authentication type to use. Set to @code{#f} to disable
27431 authentication (the default). Supported values are @code{"digest"} or
27434 @item @code{users} (default: @code{#f})
27435 If HTTP authentication is enabled (see @code{http-auth}), access will be
27436 restricted to the credentials provided here. To configure users, use a
27437 list of pairs, where the first element of the pair is the username, and
27438 the 2nd element of the pair is the password.
27441 (tailon-configuration-file
27442 (http-auth "basic")
27443 (users '(("user1" . "password1")
27444 ("user2" . "password2"))))
27451 @subsubheading Darkstat Service
27453 Darkstat is a packet sniffer that captures network traffic, calculates
27454 statistics about usage, and serves reports over HTTP.
27456 @defvar {Scheme Variable} darkstat-service-type
27457 This is the service type for the
27458 @uref{https://unix4lyfe.org/darkstat/, darkstat}
27459 service, its value must be a @code{darkstat-configuration} record as in
27463 (service darkstat-service-type
27464 (darkstat-configuration
27465 (interface "eno1")))
27469 @deftp {Data Type} darkstat-configuration
27470 Data type representing the configuration of @command{darkstat}.
27473 @item @code{package} (default: @code{darkstat})
27474 The darkstat package to use.
27476 @item @code{interface}
27477 Capture traffic on the specified network interface.
27479 @item @code{port} (default: @code{"667"})
27480 Bind the web interface to the specified port.
27482 @item @code{bind-address} (default: @code{"127.0.0.1"})
27483 Bind the web interface to the specified address.
27485 @item @code{base} (default: @code{"/"})
27486 Specify the path of the base URL@. This can be useful if
27487 @command{darkstat} is accessed via a reverse proxy.
27492 @anchor{prometheus-node-exporter}
27493 @subsubheading Prometheus Node Exporter Service
27494 @cindex prometheus-node-exporter
27496 The Prometheus ``node exporter'' makes hardware and operating system statistics
27497 provided by the Linux kernel available for the Prometheus monitoring system.
27498 This service should be deployed on all physical nodes and virtual machines,
27499 where monitoring these statistics is desirable.
27501 @defvar {Scheme variable} prometheus-node-exporter-service-type
27502 This is the service type for the
27503 @uref{https://github.com/prometheus/node_exporter/, prometheus-node-exporter}
27504 service, its value must be a @code{prometheus-node-exporter-configuration}.
27507 (service prometheus-node-exporter-service-type)
27511 @deftp {Data Type} prometheus-node-exporter-configuration
27512 Data type representing the configuration of @command{node_exporter}.
27515 @item @code{package} (default: @code{go-github-com-prometheus-node-exporter})
27516 The prometheus-node-exporter package to use.
27518 @item @code{web-listen-address} (default: @code{":9100"})
27519 Bind the web interface to the specified address.
27521 @item @code{textfile-directory} (default: @code{"/var/lib/prometheus/node-exporter"})
27522 This directory can be used to export metrics specific to this machine.
27523 Files containing metrics in the text format, with the filename ending in
27524 @code{.prom} should be placed in this directory.
27526 @item @code{extra-options} (default: @code{'()})
27527 Extra options to pass to the Prometheus node exporter.
27532 @subsubheading Zabbix server
27533 @cindex zabbix zabbix-server
27534 Zabbix is a high performance monitoring system that can collect data from a
27535 variety of sources and provide the results in a web-based interface. Alerting
27536 and reporting is built-in, as well as @dfn{templates} for common operating
27537 system metrics such as network utilization, CPU load, and disk space consumption.
27539 This service provides the central Zabbix monitoring service; you also need
27540 @ref{zabbix-front-end,@code{zabbix-front-end-service-type}} to configure Zabbix
27541 and display results, and optionally @ref{zabbix-agent,
27542 @code{zabbix-agent-service-type}} on machines that should be monitored (other
27543 data sources are supported, such as @ref{prometheus-node-exporter,
27544 Prometheus Node Exporter}).
27546 @defvar {Scheme variable} zabbix-server-service-type
27547 This is the service type for the Zabbix server service. Its value must be a
27548 @code{zabbix-server-configuration} record, shown below.
27551 @c %start of fragment
27553 @deftp {Data Type} zabbix-server-configuration
27554 Available @code{zabbix-server-configuration} fields are:
27557 @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
27558 The zabbix-server package.
27560 @item @code{user} (default: @code{"zabbix"}) (type: string)
27561 User who will run the Zabbix server.
27563 @item @code{group} (default: @code{"zabbix"}) (type: group)
27564 Group who will run the Zabbix server.
27566 @item @code{db-host} (default: @code{"127.0.0.1"}) (type: string)
27567 Database host name.
27569 @item @code{db-name} (default: @code{"zabbix"}) (type: string)
27572 @item @code{db-user} (default: @code{"zabbix"}) (type: string)
27575 @item @code{db-password} (default: @code{""}) (type: string)
27576 Database password. Please, use @code{include-files} with
27577 @code{DBPassword=SECRET} inside a specified file instead.
27579 @item @code{db-port} (default: @code{5432}) (type: number)
27582 @item @code{log-type} (default: @code{""}) (type: string)
27583 Specifies where log messages are written to:
27587 @item @code{system} - syslog.
27589 @item @code{file} - file specified with @code{log-file} parameter.
27591 @item @code{console} - standard output.
27595 @item @code{log-file} (default: @code{"/var/log/zabbix/server.log"}) (type: string)
27596 Log file name for @code{log-type} @code{file} parameter.
27598 @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_server.pid"}) (type: string)
27601 @item @code{ssl-ca-location} (default: @code{"/etc/ssl/certs/ca-certificates.crt"}) (type: string)
27602 The location of certificate authority (CA) files for SSL server
27603 certificate verification.
27605 @item @code{ssl-cert-location} (default: @code{"/etc/ssl/certs"}) (type: string)
27606 Location of SSL client certificates.
27608 @item @code{extra-options} (default: @code{""}) (type: extra-options)
27609 Extra options will be appended to Zabbix server configuration file.
27611 @item @code{include-files} (default: @code{()}) (type: include-files)
27612 You may include individual files or all files in a directory in the
27613 configuration file.
27620 @c %end of fragment
27622 @anchor{zabbix-agent}
27623 @subsubheading Zabbix agent
27624 @cindex zabbix zabbix-agent
27626 The Zabbix agent gathers information about the running system for the Zabbix
27627 monitoring server. It has a variety of built-in checks, and can be extended
27629 @uref{https://www.zabbix.com/documentation/current/en/manual/config/items/userparameters,
27630 @dfn{user parameters}}.
27632 @defvar {Scheme variable} zabbix-agent-service-type
27633 This is the service type for the Zabbix agent service. Its value must be a
27634 @code{zabbix-agent-configuration} record, shown below.
27637 @c %start of fragment
27639 @deftp {Data Type} zabbix-agent-configuration
27640 Available @code{zabbix-agent-configuration} fields are:
27643 @item @code{zabbix-agent} (default: @code{zabbix-agentd}) (type: file-like)
27644 The zabbix-agent package.
27646 @item @code{user} (default: @code{"zabbix"}) (type: string)
27647 User who will run the Zabbix agent.
27649 @item @code{group} (default: @code{"zabbix"}) (type: group)
27650 Group who will run the Zabbix agent.
27652 @item @code{hostname} (default: @code{""}) (type: string)
27653 Unique, case sensitive hostname which is required for active checks and
27654 must match hostname as configured on the server.
27656 @item @code{log-type} (default: @code{""}) (type: string)
27657 Specifies where log messages are written to:
27661 @code{system} - syslog.
27663 @item @code{file} - file specified with
27664 @code{log-file} parameter.
27666 @item @code{console} - standard output.
27670 @item @code{log-file} (default: @code{"/var/log/zabbix/agent.log"}) (type: string)
27671 Log file name for @code{log-type} @code{file} parameter.
27673 @item @code{pid-file} (default: @code{"/var/run/zabbix/zabbix_agent.pid"}) (type: string)
27676 @item @code{server} (default: @code{("127.0.0.1")}) (type: list)
27677 List of IP addresses, optionally in CIDR notation, or hostnames of
27678 Zabbix servers and Zabbix proxies. Incoming connections will be
27679 accepted only from the hosts listed here.
27681 @item @code{server-active} (default: @code{("127.0.0.1")}) (type: list)
27682 List of IP:port (or hostname:port) pairs of Zabbix servers and Zabbix
27683 proxies for active checks. If port is not specified, default port is
27684 used. If this parameter is not specified, active checks are disabled.
27686 @item @code{extra-options} (default: @code{""}) (type: extra-options)
27687 Extra options will be appended to Zabbix server configuration file.
27689 @item @code{include-files} (default: @code{()}) (type: include-files)
27690 You may include individual files or all files in a directory in the
27691 configuration file.
27698 @c %end of fragment
27700 @anchor{zabbix-front-end}
27701 @subsubheading Zabbix front-end
27702 @cindex zabbix zabbix-front-end
27704 The Zabbix front-end provides a web interface to Zabbix. It does not need
27705 to run on the same machine as the Zabbix server. This service works by
27706 extending the @ref{PHP-FPM} and @ref{NGINX} services with the configuration
27707 necessary for loading the Zabbix user interface.
27709 @defvar {Scheme variable} zabbix-front-end-service-type
27710 This is the service type for the Zabbix web frontend. Its value must be a
27711 @code{zabbix-front-end-configuration} record, shown below.
27714 @c %start of fragment
27716 @deftp {Data Type} zabbix-front-end-configuration
27717 Available @code{zabbix-front-end-configuration} fields are:
27720 @item @code{zabbix-server} (default: @code{zabbix-server}) (type: file-like)
27721 The Zabbix server package to use.
27723 @item @code{nginx} (default: @code{()}) (type: list)
27724 List of @ref{nginx-server-configuration,@code{nginx-server-configuration}}
27725 blocks for the Zabbix front-end. When empty, a default that listens on
27728 @item @code{db-host} (default: @code{"localhost"}) (type: string)
27729 Database host name.
27731 @item @code{db-port} (default: @code{5432}) (type: number)
27734 @item @code{db-name} (default: @code{"zabbix"}) (type: string)
27737 @item @code{db-user} (default: @code{"zabbix"}) (type: string)
27740 @item @code{db-password} (default: @code{""}) (type: string)
27741 Database password. Please, use @code{db-secret-file} instead.
27743 @item @code{db-secret-file} (default: @code{""}) (type: string)
27744 Secret file which will be appended to @file{zabbix.conf.php} file. This
27745 file contains credentials for use by Zabbix front-end. You are expected
27746 to create it manually.
27748 @item @code{zabbix-host} (default: @code{"localhost"}) (type: string)
27749 Zabbix server hostname.
27751 @item @code{zabbix-port} (default: @code{10051}) (type: number)
27752 Zabbix server port.
27759 @c %end of fragment
27761 @node Kerberos Services
27762 @subsection Kerberos Services
27765 The @code{(gnu services kerberos)} module provides services relating to
27766 the authentication protocol @dfn{Kerberos}.
27768 @subsubheading Krb5 Service
27770 Programs using a Kerberos client library normally
27771 expect a configuration file in @file{/etc/krb5.conf}.
27772 This service generates such a file from a definition provided in the
27773 operating system declaration.
27774 It does not cause any daemon to be started.
27776 No ``keytab'' files are provided by this service---you must explicitly create them.
27777 This service is known to work with the MIT client library, @code{mit-krb5}.
27778 Other implementations have not been tested.
27780 @defvr {Scheme Variable} krb5-service-type
27781 A service type for Kerberos 5 clients.
27785 Here is an example of its use:
27787 (service krb5-service-type
27788 (krb5-configuration
27789 (default-realm "EXAMPLE.COM")
27790 (allow-weak-crypto? #t)
27793 (name "EXAMPLE.COM")
27794 (admin-server "groucho.example.com")
27795 (kdc "karl.example.com"))
27798 (admin-server "kerb-admin.argrx.edu")
27799 (kdc "keys.argrx.edu"))))))
27803 This example provides a Kerberos@tie{}5 client configuration which:
27805 @item Recognizes two realms, @i{viz:} ``EXAMPLE.COM'' and ``ARGRX.EDU'', both
27806 of which have distinct administration servers and key distribution centers;
27807 @item Will default to the realm ``EXAMPLE.COM'' if the realm is not explicitly
27808 specified by clients;
27809 @item Accepts services which only support encryption types known to be weak.
27812 The @code{krb5-realm} and @code{krb5-configuration} types have many fields.
27813 Only the most commonly used ones are described here.
27814 For a full list, and more detailed explanation of each, see the MIT
27815 @uref{https://web.mit.edu/kerberos/krb5-devel/doc/admin/conf_files/krb5_conf.html,,krb5.conf}
27819 @deftp {Data Type} krb5-realm
27820 @cindex realm, kerberos
27823 This field is a string identifying the name of the realm.
27824 A common convention is to use the fully qualified DNS name of your organization,
27825 converted to upper case.
27827 @item @code{admin-server}
27828 This field is a string identifying the host where the administration server is
27832 This field is a string identifying the key distribution center
27837 @deftp {Data Type} krb5-configuration
27840 @item @code{allow-weak-crypto?} (default: @code{#f})
27841 If this flag is @code{#t} then services which only offer encryption algorithms
27842 known to be weak will be accepted.
27844 @item @code{default-realm} (default: @code{#f})
27845 This field should be a string identifying the default Kerberos
27846 realm for the client.
27847 You should set this field to the name of your Kerberos realm.
27848 If this value is @code{#f}
27849 then a realm must be specified with every Kerberos principal when invoking programs
27850 such as @command{kinit}.
27852 @item @code{realms}
27853 This should be a non-empty list of @code{krb5-realm} objects, which clients may
27855 Normally, one of them will have a @code{name} field matching the @code{default-realm}
27861 @subsubheading PAM krb5 Service
27864 The @code{pam-krb5} service allows for login authentication and password
27865 management via Kerberos.
27866 You will need this service if you want PAM enabled applications to authenticate
27867 users using Kerberos.
27869 @defvr {Scheme Variable} pam-krb5-service-type
27870 A service type for the Kerberos 5 PAM module.
27873 @deftp {Data Type} pam-krb5-configuration
27874 Data type representing the configuration of the Kerberos 5 PAM module.
27875 This type has the following parameters:
27877 @item @code{pam-krb5} (default: @code{pam-krb5})
27878 The pam-krb5 package to use.
27880 @item @code{minimum-uid} (default: @code{1000})
27881 The smallest user ID for which Kerberos authentications should be attempted.
27882 Local accounts with lower values will silently fail to authenticate.
27887 @node LDAP Services
27888 @subsection LDAP Services
27890 @cindex nslcd, LDAP service
27892 The @code{(gnu services authentication)} module provides the
27893 @code{nslcd-service-type}, which can be used to authenticate against an LDAP
27894 server. In addition to configuring the service itself, you may want to add
27895 @code{ldap} as a name service to the Name Service Switch. @xref{Name Service
27896 Switch} for detailed information.
27898 Here is a simple operating system declaration with a default configuration of
27899 the @code{nslcd-service-type} and a Name Service Switch configuration that
27900 consults the @code{ldap} name service last:
27903 (use-service-modules authentication)
27904 (use-modules (gnu system nss))
27910 (service nslcd-service-type)
27911 (service dhcp-client-service-type)
27913 (name-service-switch
27914 (let ((services (list (name-service (name "db"))
27915 (name-service (name "files"))
27916 (name-service (name "ldap")))))
27917 (name-service-switch
27918 (inherit %mdns-host-lookup-nss)
27919 (password services)
27922 (netgroup services)
27923 (gshadow services)))))
27926 @c %start of generated documentation for nslcd-configuration
27928 Available @code{nslcd-configuration} fields are:
27930 @deftypevr {@code{nslcd-configuration} parameter} package nss-pam-ldapd
27931 The @code{nss-pam-ldapd} package to use.
27935 @deftypevr {@code{nslcd-configuration} parameter} maybe-number threads
27936 The number of threads to start that can handle requests and perform LDAP
27937 queries. Each thread opens a separate connection to the LDAP server.
27938 The default is to start 5 threads.
27940 Defaults to @samp{disabled}.
27944 @deftypevr {@code{nslcd-configuration} parameter} string uid
27945 This specifies the user id with which the daemon should be run.
27947 Defaults to @samp{"nslcd"}.
27951 @deftypevr {@code{nslcd-configuration} parameter} string gid
27952 This specifies the group id with which the daemon should be run.
27954 Defaults to @samp{"nslcd"}.
27958 @deftypevr {@code{nslcd-configuration} parameter} log-option log
27959 This option controls the way logging is done via a list containing
27960 SCHEME and LEVEL@. The SCHEME argument may either be the symbols
27961 @samp{none} or @samp{syslog}, or an absolute file name. The LEVEL
27962 argument is optional and specifies the log level. The log level may be
27963 one of the following symbols: @samp{crit}, @samp{error}, @samp{warning},
27964 @samp{notice}, @samp{info} or @samp{debug}. All messages with the
27965 specified log level or higher are logged.
27967 Defaults to @samp{("/var/log/nslcd" info)}.
27971 @deftypevr {@code{nslcd-configuration} parameter} list uri
27972 The list of LDAP server URIs. Normally, only the first server will be
27973 used with the following servers as fall-back.
27975 Defaults to @samp{("ldap://localhost:389/")}.
27979 @deftypevr {@code{nslcd-configuration} parameter} maybe-string ldap-version
27980 The version of the LDAP protocol to use. The default is to use the
27981 maximum version supported by the LDAP library.
27983 Defaults to @samp{disabled}.
27987 @deftypevr {@code{nslcd-configuration} parameter} maybe-string binddn
27988 Specifies the distinguished name with which to bind to the directory
27989 server for lookups. The default is to bind anonymously.
27991 Defaults to @samp{disabled}.
27995 @deftypevr {@code{nslcd-configuration} parameter} maybe-string bindpw
27996 Specifies the credentials with which to bind. This option is only
27997 applicable when used with binddn.
27999 Defaults to @samp{disabled}.
28003 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmoddn
28004 Specifies the distinguished name to use when the root user tries to
28005 modify a user's password using the PAM module.
28007 Defaults to @samp{disabled}.
28011 @deftypevr {@code{nslcd-configuration} parameter} maybe-string rootpwmodpw
28012 Specifies the credentials with which to bind if the root user tries to
28013 change a user's password. This option is only applicable when used with
28016 Defaults to @samp{disabled}.
28020 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-mech
28021 Specifies the SASL mechanism to be used when performing SASL
28024 Defaults to @samp{disabled}.
28028 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-realm
28029 Specifies the SASL realm to be used when performing SASL authentication.
28031 Defaults to @samp{disabled}.
28035 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authcid
28036 Specifies the authentication identity to be used when performing SASL
28039 Defaults to @samp{disabled}.
28043 @deftypevr {@code{nslcd-configuration} parameter} maybe-string sasl-authzid
28044 Specifies the authorization identity to be used when performing SASL
28047 Defaults to @samp{disabled}.
28051 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean sasl-canonicalize?
28052 Determines whether the LDAP server host name should be canonicalised. If
28053 this is enabled the LDAP library will do a reverse host name lookup. By
28054 default, it is left up to the LDAP library whether this check is
28057 Defaults to @samp{disabled}.
28061 @deftypevr {@code{nslcd-configuration} parameter} maybe-string krb5-ccname
28062 Set the name for the GSS-API Kerberos credentials cache.
28064 Defaults to @samp{disabled}.
28068 @deftypevr {@code{nslcd-configuration} parameter} string base
28069 The directory search base.
28071 Defaults to @samp{"dc=example,dc=com"}.
28075 @deftypevr {@code{nslcd-configuration} parameter} scope-option scope
28076 Specifies the search scope (subtree, onelevel, base or children). The
28077 default scope is subtree; base scope is almost never useful for name
28078 service lookups; children scope is not supported on all servers.
28080 Defaults to @samp{(subtree)}.
28084 @deftypevr {@code{nslcd-configuration} parameter} maybe-deref-option deref
28085 Specifies the policy for dereferencing aliases. The default policy is
28086 to never dereference aliases.
28088 Defaults to @samp{disabled}.
28092 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean referrals
28093 Specifies whether automatic referral chasing should be enabled. The
28094 default behaviour is to chase referrals.
28096 Defaults to @samp{disabled}.
28100 @deftypevr {@code{nslcd-configuration} parameter} list-of-map-entries maps
28101 This option allows for custom attributes to be looked up instead of the
28102 default RFC 2307 attributes. It is a list of maps, each consisting of
28103 the name of a map, the RFC 2307 attribute to match and the query
28104 expression for the attribute as it is available in the directory.
28106 Defaults to @samp{()}.
28110 @deftypevr {@code{nslcd-configuration} parameter} list-of-filter-entries filters
28111 A list of filters consisting of the name of a map to which the filter
28112 applies and an LDAP search filter expression.
28114 Defaults to @samp{()}.
28118 @deftypevr {@code{nslcd-configuration} parameter} maybe-number bind-timelimit
28119 Specifies the time limit in seconds to use when connecting to the
28120 directory server. The default value is 10 seconds.
28122 Defaults to @samp{disabled}.
28126 @deftypevr {@code{nslcd-configuration} parameter} maybe-number timelimit
28127 Specifies the time limit (in seconds) to wait for a response from the
28128 LDAP server. A value of zero, which is the default, is to wait
28129 indefinitely for searches to be completed.
28131 Defaults to @samp{disabled}.
28135 @deftypevr {@code{nslcd-configuration} parameter} maybe-number idle-timelimit
28136 Specifies the period if inactivity (in seconds) after which the con‐
28137 nection to the LDAP server will be closed. The default is not to time
28140 Defaults to @samp{disabled}.
28144 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-sleeptime
28145 Specifies the number of seconds to sleep when connecting to all LDAP
28146 servers fails. By default one second is waited between the first
28147 failure and the first retry.
28149 Defaults to @samp{disabled}.
28153 @deftypevr {@code{nslcd-configuration} parameter} maybe-number reconnect-retrytime
28154 Specifies the time after which the LDAP server is considered to be
28155 permanently unavailable. Once this time is reached retries will be done
28156 only once per this time period. The default value is 10 seconds.
28158 Defaults to @samp{disabled}.
28162 @deftypevr {@code{nslcd-configuration} parameter} maybe-ssl-option ssl
28163 Specifies whether to use SSL/TLS or not (the default is not to). If
28164 'start-tls is specified then StartTLS is used rather than raw LDAP over
28167 Defaults to @samp{disabled}.
28171 @deftypevr {@code{nslcd-configuration} parameter} maybe-tls-reqcert-option tls-reqcert
28172 Specifies what checks to perform on a server-supplied certificate. The
28173 meaning of the values is described in the ldap.conf(5) manual page.
28175 Defaults to @samp{disabled}.
28179 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertdir
28180 Specifies the directory containing X.509 certificates for peer authen‐
28181 tication. This parameter is ignored when using GnuTLS.
28183 Defaults to @samp{disabled}.
28187 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cacertfile
28188 Specifies the path to the X.509 certificate for peer authentication.
28190 Defaults to @samp{disabled}.
28194 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-randfile
28195 Specifies the path to an entropy source. This parameter is ignored when
28198 Defaults to @samp{disabled}.
28202 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-ciphers
28203 Specifies the ciphers to use for TLS as a string.
28205 Defaults to @samp{disabled}.
28209 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-cert
28210 Specifies the path to the file containing the local certificate for
28211 client TLS authentication.
28213 Defaults to @samp{disabled}.
28217 @deftypevr {@code{nslcd-configuration} parameter} maybe-string tls-key
28218 Specifies the path to the file containing the private key for client TLS
28221 Defaults to @samp{disabled}.
28225 @deftypevr {@code{nslcd-configuration} parameter} maybe-number pagesize
28226 Set this to a number greater than 0 to request paged results from the
28227 LDAP server in accordance with RFC2696. The default (0) is to not
28228 request paged results.
28230 Defaults to @samp{disabled}.
28234 @deftypevr {@code{nslcd-configuration} parameter} maybe-ignore-users-option nss-initgroups-ignoreusers
28235 This option prevents group membership lookups through LDAP for the
28236 specified users. Alternatively, the value 'all-local may be used. With
28237 that value nslcd builds a full list of non-LDAP users on startup.
28239 Defaults to @samp{disabled}.
28243 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-min-uid
28244 This option ensures that LDAP users with a numeric user id lower than
28245 the specified value are ignored.
28247 Defaults to @samp{disabled}.
28251 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-uid-offset
28252 This option specifies an offset that is added to all LDAP numeric user
28253 ids. This can be used to avoid user id collisions with local users.
28255 Defaults to @samp{disabled}.
28259 @deftypevr {@code{nslcd-configuration} parameter} maybe-number nss-gid-offset
28260 This option specifies an offset that is added to all LDAP numeric group
28261 ids. This can be used to avoid user id collisions with local groups.
28263 Defaults to @samp{disabled}.
28267 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-nested-groups
28268 If this option is set, the member attribute of a group may point to
28269 another group. Members of nested groups are also returned in the higher
28270 level group and parent groups are returned when finding groups for a
28271 specific user. The default is not to perform extra searches for nested
28274 Defaults to @samp{disabled}.
28278 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-getgrent-skipmembers
28279 If this option is set, the group member list is not retrieved when
28280 looking up groups. Lookups for finding which groups a user belongs to
28281 will remain functional so the user will likely still get the correct
28282 groups assigned on login.
28284 Defaults to @samp{disabled}.
28288 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean nss-disable-enumeration
28289 If this option is set, functions which cause all user/group entries to
28290 be loaded from the directory will not succeed in doing so. This can
28291 dramatically reduce LDAP server load in situations where there are a
28292 great number of users and/or groups. This option is not recommended for
28293 most configurations.
28295 Defaults to @samp{disabled}.
28299 @deftypevr {@code{nslcd-configuration} parameter} maybe-string validnames
28300 This option can be used to specify how user and group names are verified
28301 within the system. This pattern is used to check all user and group
28302 names that are requested and returned from LDAP.
28304 Defaults to @samp{disabled}.
28308 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean ignorecase
28309 This specifies whether or not to perform searches using case-insensitive
28310 matching. Enabling this could open up the system to authorization
28311 bypass vulnerabilities and introduce nscd cache poisoning
28312 vulnerabilities which allow denial of service.
28314 Defaults to @samp{disabled}.
28318 @deftypevr {@code{nslcd-configuration} parameter} maybe-boolean pam-authc-ppolicy
28319 This option specifies whether password policy controls are requested and
28320 handled from the LDAP server when performing user authentication.
28322 Defaults to @samp{disabled}.
28326 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authc-search
28327 By default nslcd performs an LDAP search with the user's credentials
28328 after BIND (authentication) to ensure that the BIND operation was
28329 successful. The default search is a simple check to see if the user's
28330 DN exists. A search filter can be specified that will be used instead.
28331 It should return at least one entry.
28333 Defaults to @samp{disabled}.
28337 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-authz-search
28338 This option allows flexible fine tuning of the authorisation check that
28339 should be performed. The search filter specified is executed and if any
28340 entries match, access is granted, otherwise access is denied.
28342 Defaults to @samp{disabled}.
28346 @deftypevr {@code{nslcd-configuration} parameter} maybe-string pam-password-prohibit-message
28347 If this option is set password modification using pam_ldap will be
28348 denied and the specified message will be presented to the user instead.
28349 The message can be used to direct the user to an alternative means of
28350 changing their password.
28352 Defaults to @samp{disabled}.
28356 @deftypevr {@code{nslcd-configuration} parameter} list pam-services
28357 List of pam service names for which LDAP authentication should suffice.
28359 Defaults to @samp{()}.
28363 @c %end of generated documentation for nslcd-configuration
28367 @subsection Web Services
28372 The @code{(gnu services web)} module provides the Apache HTTP Server,
28373 the nginx web server, and also a fastcgi wrapper daemon.
28375 @subsubheading Apache HTTP Server
28377 @deffn {Scheme Variable} httpd-service-type
28378 Service type for the @uref{https://httpd.apache.org/,Apache HTTP} server
28379 (@dfn{httpd}). The value for this service type is a
28380 @code{httpd-configuration} record.
28382 A simple example configuration is given below.
28385 (service httpd-service-type
28386 (httpd-configuration
28389 (server-name "www.example.com")
28390 (document-root "/srv/http/www.example.com")))))
28393 Other services can also extend the @code{httpd-service-type} to add to
28397 (simple-service 'www.example.com-server httpd-service-type
28401 (list (string-join '("ServerName www.example.com"
28402 "DocumentRoot /srv/http/www.example.com")
28407 The details for the @code{httpd-configuration}, @code{httpd-module},
28408 @code{httpd-config-file} and @code{httpd-virtualhost} record types are
28411 @deffn {Data Type} httpd-configuration
28412 This data type represents the configuration for the httpd service.
28415 @item @code{package} (default: @code{httpd})
28416 The httpd package to use.
28418 @item @code{pid-file} (default: @code{"/var/run/httpd"})
28419 The pid file used by the shepherd-service.
28421 @item @code{config} (default: @code{(httpd-config-file)})
28422 The configuration file to use with the httpd service. The default value
28423 is a @code{httpd-config-file} record, but this can also be a different
28424 G-expression that generates a file, for example a @code{plain-file}. A
28425 file outside of the store can also be specified through a string.
28430 @deffn {Data Type} httpd-module
28431 This data type represents a module for the httpd service.
28435 The name of the module.
28438 The file for the module. This can be relative to the httpd package being
28439 used, the absolute location of a file, or a G-expression for a file
28440 within the store, for example @code{(file-append mod-wsgi
28441 "/modules/mod_wsgi.so")}.
28446 @defvr {Scheme Variable} %default-httpd-modules
28447 A default list of @code{httpd-module} objects.
28450 @deffn {Data Type} httpd-config-file
28451 This data type represents a configuration file for the httpd service.
28454 @item @code{modules} (default: @code{%default-httpd-modules})
28455 The modules to load. Additional modules can be added here, or loaded by
28456 additional configuration.
28458 For example, in order to handle requests for PHP files, you can use Apache’s
28459 @code{mod_proxy_fcgi} module along with @code{php-fpm-service-type}:
28462 (service httpd-service-type
28463 (httpd-configuration
28468 (name "proxy_module")
28469 (file "modules/mod_proxy.so"))
28471 (name "proxy_fcgi_module")
28472 (file "modules/mod_proxy_fcgi.so"))
28473 %default-httpd-modules))
28474 (extra-config (list "\
28475 <FilesMatch \\.php$>
28476 SetHandler \"proxy:unix:/var/run/php-fpm.sock|fcgi://localhost/\"
28477 </FilesMatch>"))))))
28478 (service php-fpm-service-type
28479 (php-fpm-configuration
28480 (socket "/var/run/php-fpm.sock")
28481 (socket-group "httpd")))
28484 @item @code{server-root} (default: @code{httpd})
28485 The @code{ServerRoot} in the configuration file, defaults to the httpd
28486 package. Directives including @code{Include} and @code{LoadModule} are
28487 taken as relative to the server root.
28489 @item @code{server-name} (default: @code{#f})
28490 The @code{ServerName} in the configuration file, used to specify the
28491 request scheme, hostname and port that the server uses to identify
28494 This doesn't need to be set in the server config, and can be specified
28495 in virtual hosts. The default is @code{#f} to not specify a
28498 @item @code{document-root} (default: @code{"/srv/http"})
28499 The @code{DocumentRoot} from which files will be served.
28501 @item @code{listen} (default: @code{'("80")})
28502 The list of values for the @code{Listen} directives in the config
28503 file. The value should be a list of strings, when each string can
28504 specify the port number to listen on, and optionally the IP address and
28507 @item @code{pid-file} (default: @code{"/var/run/httpd"})
28508 The @code{PidFile} to use. This should match the @code{pid-file} set in
28509 the @code{httpd-configuration} so that the Shepherd service is
28510 configured correctly.
28512 @item @code{error-log} (default: @code{"/var/log/httpd/error_log"})
28513 The @code{ErrorLog} to which the server will log errors.
28515 @item @code{user} (default: @code{"httpd"})
28516 The @code{User} which the server will answer requests as.
28518 @item @code{group} (default: @code{"httpd"})
28519 The @code{Group} which the server will answer requests as.
28521 @item @code{extra-config} (default: @code{(list "TypesConfig etc/httpd/mime.types")})
28522 A flat list of strings and G-expressions which will be added to the end
28523 of the configuration file.
28525 Any values which the service is extended with will be appended to this
28531 @deffn {Data Type} httpd-virtualhost
28532 This data type represents a virtualhost configuration block for the httpd service.
28534 These should be added to the extra-config for the httpd-service.
28537 (simple-service 'www.example.com-server httpd-service-type
28541 (list (string-join '("ServerName www.example.com"
28542 "DocumentRoot /srv/http/www.example.com")
28547 @item @code{addresses-and-ports}
28548 The addresses and ports for the @code{VirtualHost} directive.
28550 @item @code{contents}
28551 The contents of the @code{VirtualHost} directive, this should be a list
28552 of strings and G-expressions.
28558 @subsubheading NGINX
28560 @deffn {Scheme Variable} nginx-service-type
28561 Service type for the @uref{https://nginx.org/,NGinx} web server. The
28562 value for this service type is a @code{<nginx-configuration>} record.
28564 A simple example configuration is given below.
28567 (service nginx-service-type
28568 (nginx-configuration
28570 (list (nginx-server-configuration
28571 (server-name '("www.example.com"))
28572 (root "/srv/http/www.example.com"))))))
28575 In addition to adding server blocks to the service configuration
28576 directly, this service can be extended by other services to add server
28577 blocks, as in this example:
28580 (simple-service 'my-extra-server nginx-service-type
28581 (list (nginx-server-configuration
28582 (root "/srv/http/extra-website")
28583 (try-files (list "$uri" "$uri/index.html")))))
28587 At startup, @command{nginx} has not yet read its configuration file, so
28588 it uses a default file to log error messages. If it fails to load its
28589 configuration file, that is where error messages are logged. After the
28590 configuration file is loaded, the default error log file changes as per
28591 configuration. In our case, startup error messages can be found in
28592 @file{/var/run/nginx/logs/error.log}, and after configuration in
28593 @file{/var/log/nginx/error.log}. The second location can be changed
28594 with the @var{log-directory} configuration option.
28596 @deffn {Data Type} nginx-configuration
28597 This data type represents the configuration for NGinx. Some
28598 configuration can be done through this and the other provided record
28599 types, or alternatively, a config file can be provided.
28602 @item @code{nginx} (default: @code{nginx})
28603 The nginx package to use.
28605 @item @code{log-directory} (default: @code{"/var/log/nginx"})
28606 The directory to which NGinx will write log files.
28608 @item @code{run-directory} (default: @code{"/var/run/nginx"})
28609 The directory in which NGinx will create a pid file, and write temporary
28612 @item @code{server-blocks} (default: @code{'()})
28613 A list of @dfn{server blocks} to create in the generated configuration
28614 file, the elements should be of type
28615 @code{<nginx-server-configuration>}.
28617 The following example would setup NGinx to serve @code{www.example.com}
28618 from the @code{/srv/http/www.example.com} directory, without using
28621 (service nginx-service-type
28622 (nginx-configuration
28624 (list (nginx-server-configuration
28625 (server-name '("www.example.com"))
28626 (root "/srv/http/www.example.com"))))))
28629 @item @code{upstream-blocks} (default: @code{'()})
28630 A list of @dfn{upstream blocks} to create in the generated configuration
28631 file, the elements should be of type
28632 @code{<nginx-upstream-configuration>}.
28634 Configuring upstreams through the @code{upstream-blocks} can be useful
28635 when combined with @code{locations} in the
28636 @code{<nginx-server-configuration>} records. The following example
28637 creates a server configuration with one location configuration, that
28638 will proxy requests to a upstream configuration, which will handle
28639 requests with two servers.
28644 (nginx-configuration
28646 (list (nginx-server-configuration
28647 (server-name '("www.example.com"))
28648 (root "/srv/http/www.example.com")
28651 (nginx-location-configuration
28653 (body '("proxy_pass http://server-proxy;"))))))))
28655 (list (nginx-upstream-configuration
28656 (name "server-proxy")
28657 (servers (list "server1.example.com"
28658 "server2.example.com")))))))
28661 @item @code{file} (default: @code{#f})
28662 If a configuration @var{file} is provided, this will be used, rather than
28663 generating a configuration file from the provided @code{log-directory},
28664 @code{run-directory}, @code{server-blocks} and @code{upstream-blocks}. For
28665 proper operation, these arguments should match what is in @var{file} to ensure
28666 that the directories are created when the service is activated.
28668 This can be useful if you have an existing configuration file, or it's
28669 not possible to do what is required through the other parts of the
28670 nginx-configuration record.
28672 @item @code{server-names-hash-bucket-size} (default: @code{#f})
28673 Bucket size for the server names hash tables, defaults to @code{#f} to
28674 use the size of the processors cache line.
28676 @item @code{server-names-hash-bucket-max-size} (default: @code{#f})
28677 Maximum bucket size for the server names hash tables.
28679 @item @code{modules} (default: @code{'()})
28680 List of nginx dynamic modules to load. This should be a list of file
28681 names of loadable modules, as in this example:
28686 (file-append nginx-accept-language-module "\
28687 /etc/nginx/modules/ngx_http_accept_language_module.so")
28688 (file-append nginx-lua-module "\
28689 /etc/nginx/modules/ngx_http_lua_module.so")))
28692 @item @code{lua-package-path} (default: @code{'()})
28693 List of nginx lua packages to load. This should be a list of package
28694 names of loadable lua modules, as in this example:
28697 (lua-package-path (list lua-resty-core
28704 @item @code{lua-package-cpath} (default: @code{'()})
28705 List of nginx lua C packages to load. This should be a list of package
28706 names of loadable lua C modules, as in this example:
28709 (lua-package-cpath (list lua-resty-signal))
28712 @item @code{global-directives} (default: @code{'((events . ()))})
28713 Association list of global directives for the top level of the nginx
28714 configuration. Values may themselves be association lists.
28718 `((worker_processes . 16)
28720 (events . ((worker_connections . 1024)))))
28723 @item @code{extra-content} (default: @code{""})
28724 Extra content for the @code{http} block. Should be string or a string
28725 valued G-expression.
28730 @anchor{nginx-server-configuration}
28731 @deftp {Data Type} nginx-server-configuration
28732 Data type representing the configuration of an nginx server block.
28733 This type has the following parameters:
28736 @item @code{listen} (default: @code{'("80" "443 ssl")})
28737 Each @code{listen} directive sets the address and port for IP, or the
28738 path for a UNIX-domain socket on which the server will accept requests.
28739 Both address and port, or only address or only port can be specified.
28740 An address may also be a hostname, for example:
28743 '("127.0.0.1:8000" "127.0.0.1" "8000" "*:8000" "localhost:8000")
28746 @item @code{server-name} (default: @code{(list 'default)})
28747 A list of server names this server represents. @code{'default} represents the
28748 default server for connections matching no other server.
28750 @item @code{root} (default: @code{"/srv/http"})
28751 Root of the website nginx will serve.
28753 @item @code{locations} (default: @code{'()})
28754 A list of @dfn{nginx-location-configuration} or
28755 @dfn{nginx-named-location-configuration} records to use within this
28758 @item @code{index} (default: @code{(list "index.html")})
28759 Index files to look for when clients ask for a directory. If it cannot be found,
28760 Nginx will send the list of files in the directory.
28762 @item @code{try-files} (default: @code{'()})
28763 A list of files whose existence is checked in the specified order.
28764 @code{nginx} will use the first file it finds to process the request.
28766 @item @code{ssl-certificate} (default: @code{#f})
28767 Where to find the certificate for secure connections. Set it to @code{#f} if
28768 you don't have a certificate or you don't want to use HTTPS.
28770 @item @code{ssl-certificate-key} (default: @code{#f})
28771 Where to find the private key for secure connections. Set it to @code{#f} if
28772 you don't have a key or you don't want to use HTTPS.
28774 @item @code{server-tokens?} (default: @code{#f})
28775 Whether the server should add its configuration to response.
28777 @item @code{raw-content} (default: @code{'()})
28778 A list of raw lines added to the server block.
28783 @deftp {Data Type} nginx-upstream-configuration
28784 Data type representing the configuration of an nginx @code{upstream}
28785 block. This type has the following parameters:
28789 Name for this group of servers.
28791 @item @code{servers}
28792 Specify the addresses of the servers in the group. The address can be
28793 specified as a IP address (e.g.@: @samp{127.0.0.1}), domain name
28794 (e.g.@: @samp{backend1.example.com}) or a path to a UNIX socket using the
28795 prefix @samp{unix:}. For addresses using an IP address or domain name,
28796 the default port is 80, and a different port can be specified
28799 @item @code{extra-content}
28800 A string or list of strings to add to the upstream block.
28805 @deftp {Data Type} nginx-location-configuration
28806 Data type representing the configuration of an nginx @code{location}
28807 block. This type has the following parameters:
28811 URI which this location block matches.
28813 @anchor{nginx-location-configuration body}
28815 Body of the location block, specified as a list of strings. This can contain
28817 configuration directives. For example, to pass requests to a upstream
28818 server group defined using an @code{nginx-upstream-configuration} block,
28819 the following directive would be specified in the body @samp{(list "proxy_pass
28820 http://upstream-name;")}.
28825 @deftp {Data Type} nginx-named-location-configuration
28826 Data type representing the configuration of an nginx named location
28827 block. Named location blocks are used for request redirection, and not
28828 used for regular request processing. This type has the following
28833 Name to identify this location block.
28836 @xref{nginx-location-configuration body}, as the body for named location
28837 blocks can be used in a similar way to the
28838 @code{nginx-location-configuration body}. One restriction is that the
28839 body of a named location block cannot contain location blocks.
28844 @subsubheading Varnish Cache
28846 Varnish is a fast cache server that sits in between web applications
28847 and end users. It proxies requests from clients and caches the
28848 accessed URLs such that multiple requests for the same resource only
28849 creates one request to the back-end.
28851 @defvr {Scheme Variable} varnish-service-type
28852 Service type for the Varnish daemon.
28855 @deftp {Data Type} varnish-configuration
28856 Data type representing the @code{varnish} service configuration.
28857 This type has the following parameters:
28860 @item @code{package} (default: @code{varnish})
28861 The Varnish package to use.
28863 @item @code{name} (default: @code{"default"})
28864 A name for this Varnish instance. Varnish will create a directory in
28865 @file{/var/varnish/} with this name and keep temporary files there. If
28866 the name starts with a forward slash, it is interpreted as an absolute
28869 Pass the @code{-n} argument to other Varnish programs to connect to the
28870 named instance, e.g.@: @command{varnishncsa -n default}.
28872 @item @code{backend} (default: @code{"localhost:8080"})
28873 The backend to use. This option has no effect if @code{vcl} is set.
28875 @item @code{vcl} (default: #f)
28876 The @dfn{VCL} (Varnish Configuration Language) program to run. If this
28877 is @code{#f}, Varnish will proxy @code{backend} using the default
28878 configuration. Otherwise this must be a file-like object with valid
28881 @c Varnish does not support HTTPS, so keep this URL to avoid confusion.
28882 For example, to mirror @url{https://www.gnu.org,www.gnu.org} with VCL you
28883 can do something along these lines:
28886 (define %gnu-mirror
28887 (plain-file "gnu.vcl"
28889 backend gnu @{ .host = \"www.gnu.org\"; @}"))
28893 (services (cons (service varnish-service-type
28894 (varnish-configuration
28896 (vcl %gnu-mirror)))
28900 The configuration of an already running Varnish instance can be inspected
28901 and changed using the @command{varnishadm} program.
28903 Consult the @url{https://varnish-cache.org/docs/,Varnish User Guide} and
28904 @url{https://book.varnish-software.com/4.0/,Varnish Book} for
28905 comprehensive documentation on Varnish and its configuration language.
28907 @item @code{listen} (default: @code{'("localhost:80")})
28908 List of addresses Varnish will listen on.
28910 @item @code{storage} (default: @code{'("malloc,128m")})
28911 List of storage backends that will be available in VCL.
28913 @item @code{parameters} (default: @code{'()})
28914 List of run-time parameters in the form @code{'(("parameter" . "value"))}.
28916 @item @code{extra-options} (default: @code{'()})
28917 Additional arguments to pass to the @command{varnishd} process.
28922 @subsubheading Patchwork
28924 Patchwork is a patch tracking system. It can collect patches sent to a
28925 mailing list, and display them in a web interface.
28927 @defvr {Scheme Variable} patchwork-service-type
28928 Service type for Patchwork.
28931 The following example is an example of a minimal service for Patchwork, for
28932 the @code{patchwork.example.com} domain.
28935 (service patchwork-service-type
28936 (patchwork-configuration
28937 (domain "patchwork.example.com")
28939 (patchwork-settings-module
28940 (allowed-hosts (list domain))
28941 (default-from-email "patchwork@@patchwork.example.com")))
28942 (getmail-retriever-config
28943 (getmail-retriever-configuration
28944 (type "SimpleIMAPSSLRetriever")
28945 (server "imap.example.com")
28947 (username "patchwork")
28949 (list (file-append coreutils "/bin/cat")
28950 "/etc/getmail-patchwork-imap-password"))
28952 '((mailboxes . ("Patches"))))))))
28956 There are three records for configuring the Patchwork service. The
28957 @code{<patchwork-configuration>} relates to the configuration for Patchwork
28958 within the HTTPD service.
28960 The @code{settings-module} field within the @code{<patchwork-configuration>}
28961 record can be populated with the @code{<patchwork-settings-module>} record,
28962 which describes a settings module that is generated within the Guix store.
28964 For the @code{database-configuration} field within the
28965 @code{<patchwork-settings-module>}, the
28966 @code{<patchwork-database-configuration>} must be used.
28968 @deftp {Data Type} patchwork-configuration
28969 Data type representing the Patchwork service configuration. This type has the
28970 following parameters:
28973 @item @code{patchwork} (default: @code{patchwork})
28974 The Patchwork package to use.
28976 @item @code{domain}
28977 The domain to use for Patchwork, this is used in the HTTPD service virtual
28980 @item @code{settings-module}
28981 The settings module to use for Patchwork. As a Django application, Patchwork
28982 is configured with a Python module containing the settings. This can either be
28983 an instance of the @code{<patchwork-settings-module>} record, any other record
28984 that represents the settings in the store, or a directory outside of the
28987 @item @code{static-path} (default: @code{"/static/"})
28988 The path under which the HTTPD service should serve the static files.
28990 @item @code{getmail-retriever-config}
28991 The getmail-retriever-configuration record value to use with
28992 Patchwork. Getmail will be configured with this value, the messages will be
28993 delivered to Patchwork.
28998 @deftp {Data Type} patchwork-settings-module
28999 Data type representing a settings module for Patchwork. Some of these
29000 settings relate directly to Patchwork, but others relate to Django, the web
29001 framework used by Patchwork, or the Django Rest Framework library. This type
29002 has the following parameters:
29005 @item @code{database-configuration} (default: @code{(patchwork-database-configuration)})
29006 The database connection settings used for Patchwork. See the
29007 @code{<patchwork-database-configuration>} record type for more information.
29009 @item @code{secret-key-file} (default: @code{"/etc/patchwork/django-secret-key"})
29010 Patchwork, as a Django web application uses a secret key for cryptographically
29011 signing values. This file should contain a unique unpredictable value.
29013 If this file does not exist, it will be created and populated with a random
29014 value by the patchwork-setup shepherd service.
29016 This setting relates to Django.
29018 @item @code{allowed-hosts}
29019 A list of valid hosts for this Patchwork service. This should at least include
29020 the domain specified in the @code{<patchwork-configuration>} record.
29022 This is a Django setting.
29024 @item @code{default-from-email}
29025 The email address from which Patchwork should send email by default.
29027 This is a Patchwork setting.
29029 @item @code{static-url} (default: @code{#f})
29030 The URL to use when serving static assets. It can be part of a URL, or a full
29031 URL, but must end in a @code{/}.
29033 If the default value is used, the @code{static-path} value from the
29034 @code{<patchwork-configuration>} record will be used.
29036 This is a Django setting.
29038 @item @code{admins} (default: @code{'()})
29039 Email addresses to send the details of errors that occur. Each value should
29040 be a list containing two elements, the name and then the email address.
29042 This is a Django setting.
29044 @item @code{debug?} (default: @code{#f})
29045 Whether to run Patchwork in debug mode. If set to @code{#t}, detailed error
29046 messages will be shown.
29048 This is a Django setting.
29050 @item @code{enable-rest-api?} (default: @code{#t})
29051 Whether to enable the Patchwork REST API.
29053 This is a Patchwork setting.
29055 @item @code{enable-xmlrpc?} (default: @code{#t})
29056 Whether to enable the XML RPC API.
29058 This is a Patchwork setting.
29060 @item @code{force-https-links?} (default: @code{#t})
29061 Whether to use HTTPS links on Patchwork pages.
29063 This is a Patchwork setting.
29065 @item @code{extra-settings} (default: @code{""})
29066 Extra code to place at the end of the Patchwork settings module.
29071 @deftp {Data Type} patchwork-database-configuration
29072 Data type representing the database configuration for Patchwork.
29075 @item @code{engine} (default: @code{"django.db.backends.postgresql_psycopg2"})
29076 The database engine to use.
29078 @item @code{name} (default: @code{"patchwork"})
29079 The name of the database to use.
29081 @item @code{user} (default: @code{"httpd"})
29082 The user to connect to the database as.
29084 @item @code{password} (default: @code{""})
29085 The password to use when connecting to the database.
29087 @item @code{host} (default: @code{""})
29088 The host to make the database connection to.
29090 @item @code{port} (default: @code{""})
29091 The port on which to connect to the database.
29096 @subsubheading Mumi
29098 @cindex Mumi, Debbugs Web interface
29099 @cindex Debbugs, Mumi Web interface
29100 @uref{https://git.elephly.net/gitweb.cgi?p=software/mumi.git, Mumi} is a
29101 Web interface to the Debbugs bug tracker, by default for
29102 @uref{https://bugs.gnu.org, the GNU instance}. Mumi is a Web server,
29103 but it also fetches and indexes mail retrieved from Debbugs.
29105 @defvr {Scheme Variable} mumi-service-type
29106 This is the service type for Mumi.
29109 @deftp {Data Type} mumi-configuration
29110 Data type representing the Mumi service configuration. This type has the
29114 @item @code{mumi} (default: @code{mumi})
29115 The Mumi package to use.
29117 @item @code{mailer?} (default: @code{#true})
29118 Whether to enable or disable the mailer component.
29120 @item @code{mumi-configuration-sender}
29121 The email address used as the sender for comments.
29123 @item @code{mumi-configuration-smtp}
29124 A URI to configure the SMTP settings for Mailutils. This could be
29125 something like @code{sendmail:///path/to/bin/msmtp} or any other URI
29126 supported by Mailutils. @xref{SMTP Mailboxes, SMTP Mailboxes,,
29127 mailutils, GNU@tie{}Mailutils}.
29133 @subsubheading FastCGI
29136 FastCGI is an interface between the front-end and the back-end of a web
29137 service. It is a somewhat legacy facility; new web services should
29138 generally just talk HTTP between the front-end and the back-end.
29139 However there are a number of back-end services such as PHP or the
29140 optimized HTTP Git repository access that use FastCGI, so we have
29141 support for it in Guix.
29143 To use FastCGI, you configure the front-end web server (e.g., nginx) to
29144 dispatch some subset of its requests to the fastcgi backend, which
29145 listens on a local TCP or UNIX socket. There is an intermediary
29146 @code{fcgiwrap} program that sits between the actual backend process and
29147 the web server. The front-end indicates which backend program to run,
29148 passing that information to the @code{fcgiwrap} process.
29150 @defvr {Scheme Variable} fcgiwrap-service-type
29151 A service type for the @code{fcgiwrap} FastCGI proxy.
29154 @deftp {Data Type} fcgiwrap-configuration
29155 Data type representing the configuration of the @code{fcgiwrap} service.
29156 This type has the following parameters:
29158 @item @code{package} (default: @code{fcgiwrap})
29159 The fcgiwrap package to use.
29161 @item @code{socket} (default: @code{tcp:127.0.0.1:9000})
29162 The socket on which the @code{fcgiwrap} process should listen, as a
29163 string. Valid @var{socket} values include
29164 @code{unix:@var{/path/to/unix/socket}},
29165 @code{tcp:@var{dot.ted.qu.ad}:@var{port}} and
29166 @code{tcp6:[@var{ipv6_addr}]:port}.
29168 @item @code{user} (default: @code{fcgiwrap})
29169 @itemx @code{group} (default: @code{fcgiwrap})
29170 The user and group names, as strings, under which to run the
29171 @code{fcgiwrap} process. The @code{fastcgi} service will ensure that if
29172 the user asks for the specific user or group names @code{fcgiwrap} that
29173 the corresponding user and/or group is present on the system.
29175 It is possible to configure a FastCGI-backed web service to pass HTTP
29176 authentication information from the front-end to the back-end, and to
29177 allow @code{fcgiwrap} to run the back-end process as a corresponding
29178 local user. To enable this capability on the back-end, run
29179 @code{fcgiwrap} as the @code{root} user and group. Note that this
29180 capability also has to be configured on the front-end as well.
29185 @subsubheading PHP-FPM
29187 PHP-FPM (FastCGI Process Manager) is an alternative PHP FastCGI implementation
29188 with some additional features useful for sites of any size.
29190 These features include:
29192 @item Adaptive process spawning
29193 @item Basic statistics (similar to Apache's mod_status)
29194 @item Advanced process management with graceful stop/start
29195 @item Ability to start workers with different uid/gid/chroot/environment
29196 and different php.ini (replaces safe_mode)
29197 @item Stdout & stderr logging
29198 @item Emergency restart in case of accidental opcode cache destruction
29199 @item Accelerated upload support
29200 @item Support for a "slowlog"
29201 @item Enhancements to FastCGI, such as fastcgi_finish_request() -
29202 a special function to finish request & flush all data while continuing to do
29203 something time-consuming (video converting, stats processing, etc.)
29205 ...@: and much more.
29207 @defvr {Scheme Variable} php-fpm-service-type
29208 A Service type for @code{php-fpm}.
29211 @deftp {Data Type} php-fpm-configuration
29212 Data Type for php-fpm service configuration.
29214 @item @code{php} (default: @code{php})
29215 The php package to use.
29216 @item @code{socket} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.sock")})
29217 The address on which to accept FastCGI requests. Valid syntaxes are:
29219 @item @code{"ip.add.re.ss:port"}
29220 Listen on a TCP socket to a specific address on a specific port.
29221 @item @code{"port"}
29222 Listen on a TCP socket to all addresses on a specific port.
29223 @item @code{"/path/to/unix/socket"}
29224 Listen on a unix socket.
29227 @item @code{user} (default: @code{php-fpm})
29228 User who will own the php worker processes.
29229 @item @code{group} (default: @code{php-fpm})
29230 Group of the worker processes.
29231 @item @code{socket-user} (default: @code{php-fpm})
29232 User who can speak to the php-fpm socket.
29233 @item @code{socket-group} (default: @code{nginx})
29234 Group that can speak to the php-fpm socket.
29235 @item @code{pid-file} (default: @code{(string-append "/var/run/php" (version-major (package-version php)) "-fpm.pid")})
29236 The process id of the php-fpm process is written to this file
29237 once the service has started.
29238 @item @code{log-file} (default: @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.log")})
29239 Log for the php-fpm master process.
29240 @item @code{process-manager} (default: @code{(php-fpm-dynamic-process-manager-configuration)})
29241 Detailed settings for the php-fpm process manager.
29244 @item @code{<php-fpm-dynamic-process-manager-configuration>}
29245 @item @code{<php-fpm-static-process-manager-configuration>}
29246 @item @code{<php-fpm-on-demand-process-manager-configuration>}
29248 @item @code{display-errors} (default @code{#f})
29249 Determines whether php errors and warning should be sent to clients
29250 and displayed in their browsers.
29251 This is useful for local php development, but a security risk for public sites,
29252 as error messages can reveal passwords and personal data.
29253 @item @code{timezone} (default @code{#f})
29254 Specifies @code{php_admin_value[date.timezone]} parameter.
29255 @item @code{workers-logfile} (default @code{(string-append "/var/log/php" (version-major (package-version php)) "-fpm.www.log")})
29256 This file will log the @code{stderr} outputs of php worker processes.
29257 Can be set to @code{#f} to disable logging.
29258 @item @code{file} (default @code{#f})
29259 An optional override of the whole configuration.
29260 You can use the @code{mixed-text-file} function or an absolute filepath for it.
29261 @item @code{php-ini-file} (default @code{#f})
29262 An optional override of the default php settings.
29263 It may be any ``file-like'' object (@pxref{G-Expressions, file-like objects}).
29264 You can use the @code{mixed-text-file} function or an absolute filepath for it.
29266 For local development it is useful to set a higher timeout and memory
29267 limit for spawned php processes. This be accomplished with the
29268 following operating system configuration snippet:
29270 (define %local-php-ini
29271 (plain-file "php.ini"
29273 max_execution_time = 1800"))
29277 (services (cons (service php-fpm-service-type
29278 (php-fpm-configuration
29279 (php-ini-file %local-php-ini)))
29283 Consult the @url{https://www.php.net/manual/en/ini.core.php,core php.ini
29284 directives} for comprehensive documentation on the acceptable
29285 @file{php.ini} directives.
29289 @deftp {Data type} php-fpm-dynamic-process-manager-configuration
29290 Data Type for the @code{dynamic} php-fpm process manager. With the
29291 @code{dynamic} process manager, spare worker processes are kept around
29292 based on its configured limits.
29294 @item @code{max-children} (default: @code{5})
29295 Maximum of worker processes.
29296 @item @code{start-servers} (default: @code{2})
29297 How many worker processes should be started on start-up.
29298 @item @code{min-spare-servers} (default: @code{1})
29299 How many spare worker processes should be kept around at minimum.
29300 @item @code{max-spare-servers} (default: @code{3})
29301 How many spare worker processes should be kept around at maximum.
29305 @deftp {Data type} php-fpm-static-process-manager-configuration
29306 Data Type for the @code{static} php-fpm process manager. With the
29307 @code{static} process manager, an unchanging number of worker processes
29310 @item @code{max-children} (default: @code{5})
29311 Maximum of worker processes.
29315 @deftp {Data type} php-fpm-on-demand-process-manager-configuration
29316 Data Type for the @code{on-demand} php-fpm process manager. With the
29317 @code{on-demand} process manager, worker processes are only created as
29320 @item @code{max-children} (default: @code{5})
29321 Maximum of worker processes.
29322 @item @code{process-idle-timeout} (default: @code{10})
29323 The time in seconds after which a process with no requests is killed.
29328 @deffn {Scheme Procedure} nginx-php-location @
29329 [#:nginx-package nginx] @
29330 [socket (string-append "/var/run/php" @
29331 (version-major (package-version php)) @
29333 A helper function to quickly add php to an @code{nginx-server-configuration}.
29336 A simple services setup for nginx with php can look like this:
29338 (services (cons* (service dhcp-client-service-type)
29339 (service php-fpm-service-type)
29340 (service nginx-service-type
29341 (nginx-server-configuration
29342 (server-name '("example.com"))
29343 (root "/srv/http/")
29345 (list (nginx-php-location)))
29347 (ssl-certificate #f)
29348 (ssl-certificate-key #f)))
29352 @cindex cat-avatar-generator
29353 The cat avatar generator is a simple service to demonstrate the use of php-fpm
29354 in @code{Nginx}. It is used to generate cat avatar from a seed, for instance
29355 the hash of a user's email address.
29357 @deffn {Scheme Procedure} cat-avatar-generator-service @
29358 [#:cache-dir "/var/cache/cat-avatar-generator"] @
29359 [#:package cat-avatar-generator] @
29360 [#:configuration (nginx-server-configuration)]
29361 Returns an nginx-server-configuration that inherits @code{configuration}. It
29362 extends the nginx configuration to add a server block that serves @code{package},
29363 a version of cat-avatar-generator. During execution, cat-avatar-generator will
29364 be able to use @code{cache-dir} as its cache directory.
29367 A simple setup for cat-avatar-generator can look like this:
29369 (services (cons* (cat-avatar-generator-service
29371 (nginx-server-configuration
29372 (server-name '("example.com"))))
29377 @subsubheading Hpcguix-web
29379 @cindex hpcguix-web
29380 The @uref{https://github.com/UMCUGenetics/hpcguix-web/, hpcguix-web}
29381 program is a customizable web interface to browse Guix packages,
29382 initially designed for users of high-performance computing (HPC)
29385 @defvr {Scheme Variable} hpcguix-web-service-type
29386 The service type for @code{hpcguix-web}.
29389 @deftp {Data Type} hpcguix-web-configuration
29390 Data type for the hpcguix-web service configuration.
29394 A gexp (@pxref{G-Expressions}) specifying the hpcguix-web service
29395 configuration. The main items available in this spec are:
29398 @item @code{title-prefix} (default: @code{"hpcguix | "})
29399 The page title prefix.
29401 @item @code{guix-command} (default: @code{"guix"})
29402 The @command{guix} command.
29404 @item @code{package-filter-proc} (default: @code{(const #t)})
29405 A procedure specifying how to filter packages that are displayed.
29407 @item @code{package-page-extension-proc} (default: @code{(const '())})
29408 Extension package for @code{hpcguix-web}.
29410 @item @code{menu} (default: @code{'()})
29411 Additional entry in page @code{menu}.
29413 @item @code{channels} (default: @code{%default-channels})
29414 List of channels from which the package list is built (@pxref{Channels}).
29416 @item @code{package-list-expiration} (default: @code{(* 12 3600)})
29417 The expiration time, in seconds, after which the package list is rebuilt from
29418 the latest instances of the given channels.
29421 See the hpcguix-web repository for a
29422 @uref{https://github.com/UMCUGenetics/hpcguix-web/blob/master/hpcweb-configuration.scm,
29425 @item @code{package} (default: @code{hpcguix-web})
29426 The hpcguix-web package to use.
29428 @item @code{address} (default: @code{"127.0.0.1"})
29429 The IP address to listen to.
29431 @item @code{port} (default: @code{5000})
29432 The port number to listen to.
29436 A typical hpcguix-web service declaration looks like this:
29439 (service hpcguix-web-service-type
29440 (hpcguix-web-configuration
29442 #~(define site-config
29443 (hpcweb-configuration
29444 (title-prefix "Guix-HPC - ")
29445 (menu '(("/about" "ABOUT"))))))))
29449 The hpcguix-web service periodically updates the package list it publishes by
29450 pulling channels from Git. To that end, it needs to access X.509 certificates
29451 so that it can authenticate Git servers when communicating over HTTPS, and it
29452 assumes that @file{/etc/ssl/certs} contains those certificates.
29454 Thus, make sure to add @code{nss-certs} or another certificate package to the
29455 @code{packages} field of your configuration. @ref{X.509 Certificates}, for
29456 more information on X.509 certificates.
29459 @subsubheading gmnisrv
29462 The @uref{https://git.sr.ht/~sircmpwn/gmnisrv, gmnisrv} program is a
29463 simple @uref{https://gemini.circumlunar.space/, Gemini} protocol server.
29465 @deffn {Scheme Variable} gmnisrv-service-type
29466 This is the type of the gmnisrv service, whose value should be a
29467 @code{gmnisrv-configuration} object, as in this example:
29470 (service gmnisrv-service-type
29471 (gmnisrv-configuration
29472 (config-file (local-file "./my-gmnisrv.ini"))))
29476 @deftp {Data Type} gmnisrv-configuration
29477 Data type representing the configuration of gmnisrv.
29480 @item @code{package} (default: @var{gmnisrv})
29481 Package object of the gmnisrv server.
29483 @item @code{config-file} (default: @code{%default-gmnisrv-config-file})
29484 File-like object of the gmnisrv configuration file to use. The default
29485 configuration listens on port 1965 and serves files from
29486 @file{/srv/gemini}. Certificates are stored in
29487 @file{/var/lib/gemini/certs}. For more information, run @command{man
29488 gmnisrv} and @command{man gmnisrv.ini}.
29493 @subsubheading Agate
29496 The @uref{gemini://qwertqwefsday.eu/agate.gmi, Agate}
29497 (@uref{https://github.com/mbrubeck/agate, GitHub page over HTTPS})
29498 program is a simple @uref{https://gemini.circumlunar.space/, Gemini}
29499 protocol server written in Rust.
29501 @deffn {Scheme Variable} agate-service-type
29502 This is the type of the agate service, whose value should be an
29503 @code{agate-service-type} object, as in this example:
29506 (service agate-service-type
29507 (agate-configuration
29508 (content "/srv/gemini")
29509 (cert "/srv/cert.pem")
29510 (key "/srv/key.rsa")))
29513 The example above represents the minimal tweaking necessary to get Agate
29514 up and running. Specifying the path to the certificate and key is
29515 always necessary, as the Gemini protocol requires TLS by default.
29517 To obtain a certificate and a key, you could, for example, use OpenSSL,
29518 running a command similar to the following example:
29521 openssl req -x509 -newkey rsa:4096 -keyout key.rsa -out cert.pem \
29522 -days 3650 -nodes -subj "/CN=example.com"
29525 Of course, you'll have to replace @i{example.com} with your own domain
29526 name, and then point the Agate configuration towards the path of the
29527 generated key and certificate.
29531 @deftp {Data Type} agate-configuration
29532 Data type representing the configuration of Agate.
29535 @item @code{package} (default: @code{agate})
29536 The package object of the Agate server.
29538 @item @code{content} (default: @file{"/srv/gemini"})
29539 The directory from which Agate will serve files.
29541 @item @code{cert} (default: @code{#f})
29542 The path to the TLS certificate PEM file to be used for encrypted
29543 connections. Must be filled in with a value from the user.
29545 @item @code{key} (default: @code{#f})
29546 The path to the PKCS8 private key file to be used for encrypted
29547 connections. Must be filled in with a value from the user.
29549 @item @code{addr} (default: @code{'("0.0.0.0:1965" "[::]:1965")})
29550 A list of the addresses to listen on.
29552 @item @code{hostname} (default: @code{#f})
29553 The domain name of this Gemini server. Optional.
29555 @item @code{lang} (default: @code{#f})
29556 RFC 4646 language code(s) for text/gemini documents. Optional.
29558 @item @code{silent?} (default: @code{#f})
29559 Set to @code{#t} to disable logging output.
29561 @item @code{serve-secret?} (default: @code{#f})
29562 Set to @code{#t} to serve secret files (files/directories starting with
29565 @item @code{log-ip?} (default: @code{#t})
29566 Whether or not to output IP addresses when logging.
29568 @item @code{user} (default: @code{"agate"})
29569 Owner of the @code{agate} process.
29571 @item @code{group} (default: @code{"agate"})
29572 Owner's group of the @code{agate} process.
29574 @item @code{log-file} (default: @file{"/var/log/agate.log"})
29575 The file which should store the logging output of Agate.
29580 @node Certificate Services
29581 @subsection Certificate Services
29584 @cindex HTTP, HTTPS
29585 @cindex Let's Encrypt
29586 @cindex TLS certificates
29587 The @code{(gnu services certbot)} module provides a service to
29588 automatically obtain a valid TLS certificate from the Let's Encrypt
29589 certificate authority. These certificates can then be used to serve
29590 content securely over HTTPS or other TLS-based protocols, with the
29591 knowledge that the client will be able to verify the server's
29594 @url{https://letsencrypt.org/, Let's Encrypt} provides the
29595 @code{certbot} tool to automate the certification process. This tool
29596 first securely generates a key on the server. It then makes a request
29597 to the Let's Encrypt certificate authority (CA) to sign the key. The CA
29598 checks that the request originates from the host in question by using a
29599 challenge-response protocol, requiring the server to provide its
29600 response over HTTP@. If that protocol completes successfully, the CA
29601 signs the key, resulting in a certificate. That certificate is valid
29602 for a limited period of time, and therefore to continue to provide TLS
29603 services, the server needs to periodically ask the CA to renew its
29606 The certbot service automates this process: the initial key
29607 generation, the initial certification request to the Let's Encrypt
29608 service, the web server challenge/response integration, writing the
29609 certificate to disk, the automated periodic renewals, and the deployment
29610 tasks associated with the renewal (e.g.@: reloading services, copying keys
29611 with different permissions).
29613 Certbot is run twice a day, at a random minute within the hour. It
29614 won't do anything until your certificates are due for renewal or
29615 revoked, but running it regularly would give your service a chance of
29616 staying online in case a Let's Encrypt-initiated revocation happened for
29619 By using this service, you agree to the ACME Subscriber Agreement, which
29620 can be found there:
29621 @url{https://acme-v01.api.letsencrypt.org/directory}.
29623 @defvr {Scheme Variable} certbot-service-type
29624 A service type for the @code{certbot} Let's Encrypt client. Its value
29625 must be a @code{certbot-configuration} record as in this example:
29628 (define %nginx-deploy-hook
29630 "nginx-deploy-hook"
29631 #~(let ((pid (call-with-input-file "/var/run/nginx/pid" read)))
29632 (kill pid SIGHUP))))
29634 (service certbot-service-type
29635 (certbot-configuration
29636 (email "foo@@example.net")
29639 (certificate-configuration
29640 (domains '("example.net" "www.example.net"))
29641 (deploy-hook %nginx-deploy-hook))
29642 (certificate-configuration
29643 (domains '("bar.example.net")))))))
29646 See below for details about @code{certbot-configuration}.
29649 @deftp {Data Type} certbot-configuration
29650 Data type representing the configuration of the @code{certbot} service.
29651 This type has the following parameters:
29654 @item @code{package} (default: @code{certbot})
29655 The certbot package to use.
29657 @item @code{webroot} (default: @code{/var/www})
29658 The directory from which to serve the Let's Encrypt challenge/response
29661 @item @code{certificates} (default: @code{()})
29662 A list of @code{certificates-configuration}s for which to generate
29663 certificates and request signatures. Each certificate has a @code{name}
29664 and several @code{domains}.
29666 @item @code{email} (default: @code{#f})
29667 Optional email address used for registration and recovery contact.
29668 Setting this is encouraged as it allows you to receive important
29669 notifications about the account and issued certificates.
29671 @item @code{server} (default: @code{#f})
29672 Optional URL of ACME server. Setting this overrides certbot's default,
29673 which is the Let's Encrypt server.
29675 @item @code{rsa-key-size} (default: @code{2048})
29676 Size of the RSA key.
29678 @item @code{default-location} (default: @i{see below})
29679 The default @code{nginx-location-configuration}. Because @code{certbot}
29680 needs to be able to serve challenges and responses, it needs to be able
29681 to run a web server. It does so by extending the @code{nginx} web
29682 service with an @code{nginx-server-configuration} listening on the
29683 @var{domains} on port 80, and which has a
29684 @code{nginx-location-configuration} for the @code{/.well-known/} URI
29685 path subspace used by Let's Encrypt. @xref{Web Services}, for more on
29686 these nginx configuration data types.
29688 Requests to other URL paths will be matched by the
29689 @code{default-location}, which if present is added to all
29690 @code{nginx-server-configuration}s.
29692 By default, the @code{default-location} will issue a redirect from
29693 @code{http://@var{domain}/...} to @code{https://@var{domain}/...}, leaving
29694 you to define what to serve on your site via @code{https}.
29696 Pass @code{#f} to not issue a default location.
29700 @deftp {Data Type} certificate-configuration
29701 Data type representing the configuration of a certificate.
29702 This type has the following parameters:
29705 @item @code{name} (default: @i{see below})
29706 This name is used by Certbot for housekeeping and in file paths; it
29707 doesn't affect the content of the certificate itself. To see
29708 certificate names, run @code{certbot certificates}.
29710 Its default is the first provided domain.
29712 @item @code{domains} (default: @code{()})
29713 The first domain provided will be the subject CN of the certificate, and
29714 all domains will be Subject Alternative Names on the certificate.
29716 @item @code{challenge} (default: @code{#f})
29717 The challenge type that has to be run by certbot. If @code{#f} is specified,
29718 default to the HTTP challenge. If a value is specified, defaults to the
29719 manual plugin (see @code{authentication-hook}, @code{cleanup-hook} and
29720 the documentation at @url{https://certbot.eff.org/docs/using.html#hooks}),
29721 and gives Let's Encrypt permission to log the public IP address of the
29722 requesting machine.
29724 @item @code{csr} (default: @code{#f})
29725 File name of Certificate Signing Request (CSR) in DER or PEM format.
29726 If @code{#f} is specified, this argument will not be passed to certbot.
29727 If a value is specified, certbot will use it to obtain a certificate, instead of
29728 using a self-generated CSR.
29729 The domain-name(s) mentioned in @code{domains}, must be consistent with the
29730 domain-name(s) mentioned in CSR file.
29732 @item @code{authentication-hook} (default: @code{#f})
29733 Command to be run in a shell once for each certificate challenge to be
29734 answered. For this command, the shell variable @code{$CERTBOT_DOMAIN}
29735 will contain the domain being authenticated, @code{$CERTBOT_VALIDATION}
29736 contains the validation string and @code{$CERTBOT_TOKEN} contains the
29737 file name of the resource requested when performing an HTTP-01 challenge.
29739 @item @code{cleanup-hook} (default: @code{#f})
29740 Command to be run in a shell once for each certificate challenge that
29741 have been answered by the @code{auth-hook}. For this command, the shell
29742 variables available in the @code{auth-hook} script are still available, and
29743 additionally @code{$CERTBOT_AUTH_OUTPUT} will contain the standard output
29744 of the @code{auth-hook} script.
29746 @item @code{deploy-hook} (default: @code{#f})
29747 Command to be run in a shell once for each successfully issued
29748 certificate. For this command, the shell variable
29749 @code{$RENEWED_LINEAGE} will point to the config live subdirectory (for
29750 example, @samp{"/etc/letsencrypt/live/example.com"}) containing the new
29751 certificates and keys; the shell variable @code{$RENEWED_DOMAINS} will
29752 contain a space-delimited list of renewed certificate domains (for
29753 example, @samp{"example.com www.example.com"}.
29758 For each @code{certificate-configuration}, the certificate is saved to
29759 @code{/etc/letsencrypt/live/@var{name}/fullchain.pem} and the key is
29760 saved to @code{/etc/letsencrypt/live/@var{name}/privkey.pem}.
29762 @subsection DNS Services
29763 @cindex DNS (domain name system)
29764 @cindex domain name system (DNS)
29766 The @code{(gnu services dns)} module provides services related to the
29767 @dfn{domain name system} (DNS). It provides a server service for hosting
29768 an @emph{authoritative} DNS server for multiple zones, slave or master.
29769 This service uses @uref{https://www.knot-dns.cz/, Knot DNS}. And also a
29770 caching and forwarding DNS server for the LAN, which uses
29771 @uref{http://www.thekelleys.org.uk/dnsmasq/doc.html, dnsmasq}.
29773 @subsubheading Knot Service
29775 An example configuration of an authoritative server for two zones, one master
29779 (define-zone-entries example.org.zone
29780 ;; Name TTL Class Type Data
29781 ("@@" "" "IN" "A" "127.0.0.1")
29782 ("@@" "" "IN" "NS" "ns")
29783 ("ns" "" "IN" "A" "127.0.0.1"))
29785 (define master-zone
29786 (knot-zone-configuration
29787 (domain "example.org")
29789 (origin "example.org")
29790 (entries example.org.zone)))))
29793 (knot-zone-configuration
29794 (domain "plop.org")
29795 (dnssec-policy "default")
29796 (master (list "plop-master"))))
29798 (define plop-master
29799 (knot-remote-configuration
29801 (address (list "208.76.58.171"))))
29805 (services (cons* (service knot-service-type
29806 (knot-configuration
29807 (remotes (list plop-master))
29808 (zones (list master-zone slave-zone))))
29813 @deffn {Scheme Variable} knot-service-type
29814 This is the type for the Knot DNS server.
29816 Knot DNS is an authoritative DNS server, meaning that it can serve multiple
29817 zones, that is to say domain names you would buy from a registrar. This server
29818 is not a resolver, meaning that it can only resolve names for which it is
29819 authoritative. This server can be configured to serve zones as a master server
29820 or a slave server as a per-zone basis. Slave zones will get their data from
29821 masters, and will serve it as an authoritative server. From the point of view
29822 of a resolver, there is no difference between master and slave.
29824 The following data types are used to configure the Knot DNS server:
29827 @deftp {Data Type} knot-key-configuration
29828 Data type representing a key.
29829 This type has the following parameters:
29832 @item @code{id} (default: @code{""})
29833 An identifier for other configuration fields to refer to this key. IDs must
29834 be unique and must not be empty.
29836 @item @code{algorithm} (default: @code{#f})
29837 The algorithm to use. Choose between @code{#f}, @code{'hmac-md5},
29838 @code{'hmac-sha1}, @code{'hmac-sha224}, @code{'hmac-sha256}, @code{'hmac-sha384}
29839 and @code{'hmac-sha512}.
29841 @item @code{secret} (default: @code{""})
29842 The secret key itself.
29847 @deftp {Data Type} knot-acl-configuration
29848 Data type representing an Access Control List (ACL) configuration.
29849 This type has the following parameters:
29852 @item @code{id} (default: @code{""})
29853 An identifier for other configuration fields to refer to this key. IDs must be
29854 unique and must not be empty.
29856 @item @code{address} (default: @code{'()})
29857 An ordered list of IP addresses, network subnets, or network ranges represented
29858 with strings. The query must match one of them. Empty value means that
29859 address match is not required.
29861 @item @code{key} (default: @code{'()})
29862 An ordered list of references to keys represented with strings. The string
29863 must match a key ID defined in a @code{knot-key-configuration}. No key means
29864 that a key is not require to match that ACL.
29866 @item @code{action} (default: @code{'()})
29867 An ordered list of actions that are permitted or forbidden by this ACL@. Possible
29868 values are lists of zero or more elements from @code{'transfer}, @code{'notify}
29869 and @code{'update}.
29871 @item @code{deny?} (default: @code{#f})
29872 When true, the ACL defines restrictions. Listed actions are forbidden. When
29873 false, listed actions are allowed.
29878 @deftp {Data Type} zone-entry
29879 Data type representing a record entry in a zone file.
29880 This type has the following parameters:
29883 @item @code{name} (default: @code{"@@"})
29884 The name of the record. @code{"@@"} refers to the origin of the zone. Names
29885 are relative to the origin of the zone. For example, in the @code{example.org}
29886 zone, @code{"ns.example.org"} actually refers to @code{ns.example.org.example.org}.
29887 Names ending with a dot are absolute, which means that @code{"ns.example.org."}
29888 refers to @code{ns.example.org}.
29890 @item @code{ttl} (default: @code{""})
29891 The Time-To-Live (TTL) of this record. If not set, the default TTL is used.
29893 @item @code{class} (default: @code{"IN"})
29894 The class of the record. Knot currently supports only @code{"IN"} and
29895 partially @code{"CH"}.
29897 @item @code{type} (default: @code{"A"})
29898 The type of the record. Common types include A (IPv4 address), AAAA (IPv6
29899 address), NS (Name Server) and MX (Mail eXchange). Many other types are
29902 @item @code{data} (default: @code{""})
29903 The data contained in the record. For instance an IP address associated with
29904 an A record, or a domain name associated with an NS record. Remember that
29905 domain names are relative to the origin unless they end with a dot.
29910 @deftp {Data Type} zone-file
29911 Data type representing the content of a zone file.
29912 This type has the following parameters:
29915 @item @code{entries} (default: @code{'()})
29916 The list of entries. The SOA record is taken care of, so you don't need to
29917 put it in the list of entries. This list should probably contain an entry
29918 for your primary authoritative DNS server. Other than using a list of entries
29919 directly, you can use @code{define-zone-entries} to define a object containing
29920 the list of entries more easily, that you can later pass to the @code{entries}
29921 field of the @code{zone-file}.
29923 @item @code{origin} (default: @code{""})
29924 The name of your zone. This parameter cannot be empty.
29926 @item @code{ns} (default: @code{"ns"})
29927 The domain of your primary authoritative DNS server. The name is relative to
29928 the origin, unless it ends with a dot. It is mandatory that this primary
29929 DNS server corresponds to an NS record in the zone and that it is associated
29930 to an IP address in the list of entries.
29932 @item @code{mail} (default: @code{"hostmaster"})
29933 An email address people can contact you at, as the owner of the zone. This
29934 is translated as @code{<mail>@@<origin>}.
29936 @item @code{serial} (default: @code{1})
29937 The serial number of the zone. As this is used to keep track of changes by
29938 both slaves and resolvers, it is mandatory that it @emph{never} decreases.
29939 Always increment it when you make a change in your zone.
29941 @item @code{refresh} (default: @code{(* 2 24 3600)})
29942 The frequency at which slaves will do a zone transfer. This value is a number
29943 of seconds. It can be computed by multiplications or with
29944 @code{(string->duration)}.
29946 @item @code{retry} (default: @code{(* 15 60)})
29947 The period after which a slave will retry to contact its master when it fails
29948 to do so a first time.
29950 @item @code{expiry} (default: @code{(* 14 24 3600)})
29951 Default TTL of records. Existing records are considered correct for at most
29952 this amount of time. After this period, resolvers will invalidate their cache
29953 and check again that it still exists.
29955 @item @code{nx} (default: @code{3600})
29956 Default TTL of inexistent records. This delay is usually short because you want
29957 your new domains to reach everyone quickly.
29962 @deftp {Data Type} knot-remote-configuration
29963 Data type representing a remote configuration.
29964 This type has the following parameters:
29967 @item @code{id} (default: @code{""})
29968 An identifier for other configuration fields to refer to this remote. IDs must
29969 be unique and must not be empty.
29971 @item @code{address} (default: @code{'()})
29972 An ordered list of destination IP addresses. Addresses are tried in sequence.
29973 An optional port can be given with the @@ separator. For instance:
29974 @code{(list "1.2.3.4" "2.3.4.5@@53")}. Default port is 53.
29976 @item @code{via} (default: @code{'()})
29977 An ordered list of source IP addresses. An empty list will have Knot choose
29978 an appropriate source IP@. An optional port can be given with the @@ separator.
29979 The default is to choose at random.
29981 @item @code{key} (default: @code{#f})
29982 A reference to a key, that is a string containing the identifier of a key
29983 defined in a @code{knot-key-configuration} field.
29988 @deftp {Data Type} knot-keystore-configuration
29989 Data type representing a keystore to hold dnssec keys.
29990 This type has the following parameters:
29993 @item @code{id} (default: @code{""})
29994 The id of the keystore. It must not be empty.
29996 @item @code{backend} (default: @code{'pem})
29997 The backend to store the keys in. Can be @code{'pem} or @code{'pkcs11}.
29999 @item @code{config} (default: @code{"/var/lib/knot/keys/keys"})
30000 The configuration string of the backend. An example for the PKCS#11 is:
30001 @code{"pkcs11:token=knot;pin-value=1234 /gnu/store/.../lib/pkcs11/libsofthsm2.so"}.
30002 For the pem backend, the string represents a path in the file system.
30007 @deftp {Data Type} knot-policy-configuration
30008 Data type representing a dnssec policy. Knot DNS is able to automatically
30009 sign your zones. It can either generate and manage your keys automatically or
30010 use keys that you generate.
30012 Dnssec is usually implemented using two keys: a Key Signing Key (KSK) that is
30013 used to sign the second, and a Zone Signing Key (ZSK) that is used to sign the
30014 zone. In order to be trusted, the KSK needs to be present in the parent zone
30015 (usually a top-level domain). If your registrar supports dnssec, you will
30016 have to send them your KSK's hash so they can add a DS record in their zone.
30017 This is not automated and need to be done each time you change your KSK.
30019 The policy also defines the lifetime of keys. Usually, ZSK can be changed
30020 easily and use weaker cryptographic functions (they use lower parameters) in
30021 order to sign records quickly, so they are changed often. The KSK however
30022 requires manual interaction with the registrar, so they are changed less often
30023 and use stronger parameters because they sign only one record.
30025 This type has the following parameters:
30028 @item @code{id} (default: @code{""})
30029 The id of the policy. It must not be empty.
30031 @item @code{keystore} (default: @code{"default"})
30032 A reference to a keystore, that is a string containing the identifier of a
30033 keystore defined in a @code{knot-keystore-configuration} field. The
30034 @code{"default"} identifier means the default keystore (a kasp database that
30035 was setup by this service).
30037 @item @code{manual?} (default: @code{#f})
30038 Whether the key management is manual or automatic.
30040 @item @code{single-type-signing?} (default: @code{#f})
30041 When @code{#t}, use the Single-Type Signing Scheme.
30043 @item @code{algorithm} (default: @code{"ecdsap256sha256"})
30044 An algorithm of signing keys and issued signatures.
30046 @item @code{ksk-size} (default: @code{256})
30047 The length of the KSK@. Note that this value is correct for the default
30048 algorithm, but would be unsecure for other algorithms.
30050 @item @code{zsk-size} (default: @code{256})
30051 The length of the ZSK@. Note that this value is correct for the default
30052 algorithm, but would be unsecure for other algorithms.
30054 @item @code{dnskey-ttl} (default: @code{'default})
30055 The TTL value for DNSKEY records added into zone apex. The special
30056 @code{'default} value means same as the zone SOA TTL.
30058 @item @code{zsk-lifetime} (default: @code{(* 30 24 3600)})
30059 The period between ZSK publication and the next rollover initiation.
30061 @item @code{propagation-delay} (default: @code{(* 24 3600)})
30062 An extra delay added for each key rollover step. This value should be high
30063 enough to cover propagation of data from the master server to all slaves.
30065 @item @code{rrsig-lifetime} (default: @code{(* 14 24 3600)})
30066 A validity period of newly issued signatures.
30068 @item @code{rrsig-refresh} (default: @code{(* 7 24 3600)})
30069 A period how long before a signature expiration the signature will be refreshed.
30071 @item @code{nsec3?} (default: @code{#f})
30072 When @code{#t}, NSEC3 will be used instead of NSEC.
30074 @item @code{nsec3-iterations} (default: @code{5})
30075 The number of additional times the hashing is performed.
30077 @item @code{nsec3-salt-length} (default: @code{8})
30078 The length of a salt field in octets, which is appended to the original owner
30079 name before hashing.
30081 @item @code{nsec3-salt-lifetime} (default: @code{(* 30 24 3600)})
30082 The validity period of newly issued salt field.
30087 @deftp {Data Type} knot-zone-configuration
30088 Data type representing a zone served by Knot.
30089 This type has the following parameters:
30092 @item @code{domain} (default: @code{""})
30093 The domain served by this configuration. It must not be empty.
30095 @item @code{file} (default: @code{""})
30096 The file where this zone is saved. This parameter is ignored by master zones.
30097 Empty means default location that depends on the domain name.
30099 @item @code{zone} (default: @code{(zone-file)})
30100 The content of the zone file. This parameter is ignored by slave zones. It
30101 must contain a zone-file record.
30103 @item @code{master} (default: @code{'()})
30104 A list of master remotes. When empty, this zone is a master. When set, this
30105 zone is a slave. This is a list of remotes identifiers.
30107 @item @code{ddns-master} (default: @code{#f})
30108 The main master. When empty, it defaults to the first master in the list of
30111 @item @code{notify} (default: @code{'()})
30112 A list of slave remote identifiers.
30114 @item @code{acl} (default: @code{'()})
30115 A list of acl identifiers.
30117 @item @code{semantic-checks?} (default: @code{#f})
30118 When set, this adds more semantic checks to the zone.
30120 @item @code{zonefile-sync} (default: @code{0})
30121 The delay between a modification in memory and on disk. 0 means immediate
30124 @item @code{zonefile-load} (default: @code{#f})
30125 The way the zone file contents are applied during zone load. Possible values
30129 @item @code{#f} for using the default value from Knot,
30130 @item @code{'none} for not using the zone file at all,
30131 @item @code{'difference} for computing the difference between already available
30132 contents and zone contents and applying it to the current zone contents,
30133 @item @code{'difference-no-serial} for the same as @code{'difference}, but
30134 ignoring the SOA serial in the zone file, while the server takes care of it
30136 @item @code{'whole} for loading zone contents from the zone file.
30139 @item @code{journal-content} (default: @code{#f})
30140 The way the journal is used to store zone and its changes. Possible values
30141 are @code{'none} to not use it at all, @code{'changes} to store changes and
30142 @code{'all} to store contents. @code{#f} does not set this option, so the
30143 default value from Knot is used.
30145 @item @code{max-journal-usage} (default: @code{#f})
30146 The maximum size for the journal on disk. @code{#f} does not set this option,
30147 so the default value from Knot is used.
30149 @item @code{max-journal-depth} (default: @code{#f})
30150 The maximum size of the history. @code{#f} does not set this option, so the
30151 default value from Knot is used.
30153 @item @code{max-zone-size} (default: @code{#f})
30154 The maximum size of the zone file. This limit is enforced for incoming
30155 transfer and updates. @code{#f} does not set this option, so the default
30156 value from Knot is used.
30158 @item @code{dnssec-policy} (default: @code{#f})
30159 A reference to a @code{knot-policy-configuration} record, or the special
30160 name @code{"default"}. If the value is @code{#f}, there is no dnssec signing
30163 @item @code{serial-policy} (default: @code{'increment})
30164 A policy between @code{'increment} and @code{'unixtime}.
30169 @deftp {Data Type} knot-configuration
30170 Data type representing the Knot configuration.
30171 This type has the following parameters:
30174 @item @code{knot} (default: @code{knot})
30177 @item @code{run-directory} (default: @code{"/var/run/knot"})
30178 The run directory. This directory will be used for pid file and sockets.
30180 @item @code{includes} (default: @code{'()})
30181 A list of strings or file-like objects denoting other files that must be
30182 included at the top of the configuration file.
30184 @cindex secrets, Knot service
30185 This can be used to manage secrets out-of-band. For example, secret
30186 keys may be stored in an out-of-band file not managed by Guix, and
30187 thus not visible in @file{/gnu/store}---e.g., you could store secret
30188 key configuration in @file{/etc/knot/secrets.conf} and add this file
30189 to the @code{includes} list.
30191 One can generate a secret tsig key (for nsupdate and zone transfers with the
30192 keymgr command from the knot package. Note that the package is not automatically
30193 installed by the service. The following example shows how to generate a new
30197 keymgr -t mysecret > /etc/knot/secrets.conf
30198 chmod 600 /etc/knot/secrets.conf
30201 Also note that the generated key will be named @var{mysecret}, so it is the
30202 name that needs to be used in the @var{key} field of the
30203 @code{knot-acl-configuration} record and in other places that need to refer
30206 It can also be used to add configuration not supported by this interface.
30208 @item @code{listen-v4} (default: @code{"0.0.0.0"})
30209 An ip address on which to listen.
30211 @item @code{listen-v6} (default: @code{"::"})
30212 An ip address on which to listen.
30214 @item @code{listen-port} (default: @code{53})
30215 A port on which to listen.
30217 @item @code{keys} (default: @code{'()})
30218 The list of knot-key-configuration used by this configuration.
30220 @item @code{acls} (default: @code{'()})
30221 The list of knot-acl-configuration used by this configuration.
30223 @item @code{remotes} (default: @code{'()})
30224 The list of knot-remote-configuration used by this configuration.
30226 @item @code{zones} (default: @code{'()})
30227 The list of knot-zone-configuration used by this configuration.
30232 @subsubheading Knot Resolver Service
30234 @deffn {Scheme Variable} knot-resolver-service-type
30235 This is the type of the knot resolver service, whose value should be
30236 an @code{knot-resolver-configuration} object as in this example:
30239 (service knot-resolver-service-type
30240 (knot-resolver-configuration
30241 (kresd-config-file (plain-file "kresd.conf" "
30242 net.listen('192.168.0.1', 5353)
30243 user('knot-resolver', 'knot-resolver')
30244 modules = @{ 'hints > iterate', 'stats', 'predict' @}
30245 cache.size = 100 * MB
30249 For more information, refer its @url{https://knot-resolver.readthedocs.org/en/stable/daemon.html#configuration, manual}.
30252 @deftp {Data Type} knot-resolver-configuration
30253 Data type representing the configuration of knot-resolver.
30256 @item @code{package} (default: @var{knot-resolver})
30257 Package object of the knot DNS resolver.
30259 @item @code{kresd-config-file} (default: %kresd.conf)
30260 File-like object of the kresd configuration file to use, by default it
30261 will listen on @code{127.0.0.1} and @code{::1}.
30263 @item @code{garbage-collection-interval} (default: 1000)
30264 Number of milliseconds for @code{kres-cache-gc} to periodically trim the cache.
30270 @subsubheading Dnsmasq Service
30272 @deffn {Scheme Variable} dnsmasq-service-type
30273 This is the type of the dnsmasq service, whose value should be an
30274 @code{dnsmasq-configuration} object as in this example:
30277 (service dnsmasq-service-type
30278 (dnsmasq-configuration
30280 (servers '("192.168.1.1"))))
30284 @deftp {Data Type} dnsmasq-configuration
30285 Data type representing the configuration of dnsmasq.
30288 @item @code{package} (default: @var{dnsmasq})
30289 Package object of the dnsmasq server.
30291 @item @code{no-hosts?} (default: @code{#f})
30292 When true, don't read the hostnames in /etc/hosts.
30294 @item @code{port} (default: @code{53})
30295 The port to listen on. Setting this to zero completely disables DNS
30296 responses, leaving only DHCP and/or TFTP functions.
30298 @item @code{local-service?} (default: @code{#t})
30299 Accept DNS queries only from hosts whose address is on a local subnet,
30300 ie a subnet for which an interface exists on the server.
30302 @item @code{listen-addresses} (default: @code{'()})
30303 Listen on the given IP addresses.
30305 @item @code{resolv-file} (default: @code{"/etc/resolv.conf"})
30306 The file to read the IP address of the upstream nameservers from.
30308 @item @code{no-resolv?} (default: @code{#f})
30309 When true, don't read @var{resolv-file}.
30311 @item @code{forward-private-reverse-lookup?} (default: @code{#t})
30312 When false, all reverse lookups for private IP ranges are answered with
30313 "no such domain" rather than being forwarded upstream.
30315 @item @code{query-servers-in-order?} (default: @code{#f})
30316 When true, dnsmasq queries the servers in the same order as they appear
30319 @item @code{servers} (default: @code{'()})
30320 Specify IP address of upstream servers directly.
30322 @item @code{addresses} (default: @code{'()})
30323 For each entry, specify an IP address to return for any host in the
30324 given domains. Queries in the domains are never forwarded and always
30325 replied to with the specified IP address.
30327 This is useful for redirecting hosts locally, for example:
30330 (service dnsmasq-service-type
30331 (dnsmasq-configuration
30333 '(; Redirect to a local web-server.
30334 "/example.org/127.0.0.1"
30335 ; Redirect subdomain to a specific IP.
30336 "/subdomain.example.org/192.168.1.42"))))
30339 Note that rules in @file{/etc/hosts} take precedence over this.
30341 @item @code{cache-size} (default: @code{150})
30342 Set the size of dnsmasq's cache. Setting the cache size to zero
30345 @item @code{negative-cache?} (default: @code{#t})
30346 When false, disable negative caching.
30348 @item @code{cpe-id} (default: @code{#f})
30349 If set, add a CPE (Customer-Premises Equipment) identifier to DNS
30350 queries which are forwarded upstream.
30352 @item @code{tftp-enable?} (default: @code{#f})
30353 Whether to enable the built-in TFTP server.
30355 @item @code{tftp-no-fail?} (default: @code{#f})
30356 If true, does not fail dnsmasq if the TFTP server could not start up.
30358 @item @code{tftp-single-port?} (default: @code{#f})
30359 Whether to use only one single port for TFTP.
30361 @item @code{tftp-secure?} (default: @code{#f})
30362 If true, only files owned by the user running the dnsmasq process are accessible.
30364 If dnsmasq is being run as root, different rules apply:
30365 @code{tftp-secure?} has no effect, but only files which have the
30366 world-readable bit set are accessible.
30368 @item @code{tftp-max} (default: @code{#f})
30369 If set, sets the maximal number of concurrent connections allowed.
30371 @item @code{tftp-mtu} (default: @code{#f})
30372 If set, sets the MTU for TFTP packets to that value.
30374 @item @code{tftp-no-blocksize?} (default: @code{#f})
30375 If true, stops the TFTP server from negotiating the blocksize with a client.
30377 @item @code{tftp-lowercase?} (default: @code{#f})
30378 Whether to convert all filenames in TFTP requests to lowercase.
30380 @item @code{tftp-port-range} (default: @code{#f})
30381 If set, fixes the dynamical ports (one per client) to the given range
30382 (@code{"<start>,<end>"}).
30384 @item @code{tftp-root} (default: @code{/var/empty,lo})
30385 Look for files to transfer using TFTP relative to the given directory.
30386 When this is set, TFTP paths which include @samp{..} are rejected, to stop clients
30387 getting outside the specified root. Absolute paths (starting with @samp{/}) are
30388 allowed, but they must be within the TFTP-root. If the optional interface
30389 argument is given, the directory is only used for TFTP requests via that
30392 @item @code{tftp-unique-root} (default: @code{#f})
30393 If set, add the IP or hardware address of the TFTP client as a path component
30394 on the end of the TFTP-root. Only valid if a TFTP root is set and the
30395 directory exists. Defaults to adding IP address (in standard dotted-quad
30398 For instance, if @option{--tftp-root} is @samp{/tftp} and client
30399 @samp{1.2.3.4} requests file @file{myfile} then the effective path will
30400 be @file{/tftp/1.2.3.4/myfile} if @file{/tftp/1.2.3.4} exists or
30401 @file{/tftp/myfile} otherwise. When @samp{=mac} is specified it will
30402 append the MAC address instead, using lowercase zero padded digits
30403 separated by dashes, e.g.: @samp{01-02-03-04-aa-bb}. Note that
30404 resolving MAC addresses is only possible if the client is in the local
30405 network or obtained a DHCP lease from dnsmasq.
30410 @subsubheading ddclient Service
30413 The ddclient service described below runs the ddclient daemon, which takes
30414 care of automatically updating DNS entries for service providers such as
30415 @uref{https://dyn.com/dns/, Dyn}.
30417 The following example show instantiates the service with its default
30421 (service ddclient-service-type)
30424 Note that ddclient needs to access credentials that are stored in a
30425 @dfn{secret file}, by default @file{/etc/ddclient/secrets} (see
30426 @code{secret-file} below). You are expected to create this file manually, in
30427 an ``out-of-band'' fashion (you @emph{could} make this file part of the
30428 service configuration, for instance by using @code{plain-file}, but it will be
30429 world-readable @i{via} @file{/gnu/store}). See the examples in the
30430 @file{share/ddclient} directory of the @code{ddclient} package.
30432 @c %start of fragment
30434 Available @code{ddclient-configuration} fields are:
30436 @deftypevr {@code{ddclient-configuration} parameter} package ddclient
30437 The ddclient package.
30441 @deftypevr {@code{ddclient-configuration} parameter} integer daemon
30442 The period after which ddclient will retry to check IP and domain name.
30444 Defaults to @samp{300}.
30448 @deftypevr {@code{ddclient-configuration} parameter} boolean syslog
30449 Use syslog for the output.
30451 Defaults to @samp{#t}.
30455 @deftypevr {@code{ddclient-configuration} parameter} string mail
30458 Defaults to @samp{"root"}.
30462 @deftypevr {@code{ddclient-configuration} parameter} string mail-failure
30463 Mail failed update to user.
30465 Defaults to @samp{"root"}.
30469 @deftypevr {@code{ddclient-configuration} parameter} string pid
30470 The ddclient PID file.
30472 Defaults to @samp{"/var/run/ddclient/ddclient.pid"}.
30476 @deftypevr {@code{ddclient-configuration} parameter} boolean ssl
30477 Enable SSL support.
30479 Defaults to @samp{#t}.
30483 @deftypevr {@code{ddclient-configuration} parameter} string user
30484 Specifies the user name or ID that is used when running ddclient
30487 Defaults to @samp{"ddclient"}.
30491 @deftypevr {@code{ddclient-configuration} parameter} string group
30492 Group of the user who will run the ddclient program.
30494 Defaults to @samp{"ddclient"}.
30498 @deftypevr {@code{ddclient-configuration} parameter} string secret-file
30499 Secret file which will be appended to @file{ddclient.conf} file. This
30500 file contains credentials for use by ddclient. You are expected to
30501 create it manually.
30503 Defaults to @samp{"/etc/ddclient/secrets.conf"}.
30507 @deftypevr {@code{ddclient-configuration} parameter} list extra-options
30508 Extra options will be appended to @file{ddclient.conf} file.
30510 Defaults to @samp{()}.
30515 @c %end of fragment
30519 @subsection VPN Services
30520 @cindex VPN (virtual private network)
30521 @cindex virtual private network (VPN)
30523 The @code{(gnu services vpn)} module provides services related to
30524 @dfn{virtual private networks} (VPNs).
30526 @subsubheading Bitmask
30528 @defvr {Scheme Variable} bitmask-service-type
30529 A service type for the @uref{https://bitmask.net, Bitmask} VPN client. It makes
30530 the client available in the system and loads its polkit policy. Please note that
30531 the client expects an active polkit-agent, which is either run by your
30532 desktop-environment or should be run manually.
30535 @subsubheading OpenVPN
30537 It provides a @emph{client} service for your machine to connect to a
30538 VPN, and a @emph{server} service for your machine to host a VPN@.
30540 @deffn {Scheme Procedure} openvpn-client-service @
30541 [#:config (openvpn-client-configuration)]
30543 Return a service that runs @command{openvpn}, a VPN daemon, as a client.
30546 @deffn {Scheme Procedure} openvpn-server-service @
30547 [#:config (openvpn-server-configuration)]
30549 Return a service that runs @command{openvpn}, a VPN daemon, as a server.
30551 Both can be run simultaneously.
30554 @c %automatically generated documentation
30556 @deftp {Data Type} openvpn-client-configuration
30557 Available @code{openvpn-client-configuration} fields are:
30560 @item @code{openvpn} (default: @code{openvpn}) (type: file-like)
30561 The OpenVPN package.
30563 @item @code{pid-file} (default: @code{"/var/run/openvpn/openvpn.pid"}) (type: string)
30564 The OpenVPN pid file.
30566 @item @code{proto} (default: @code{udp}) (type: proto)
30567 The protocol (UDP or TCP) used to open a channel between clients and
30570 @item @code{dev} (default: @code{tun}) (type: dev)
30571 The device type used to represent the VPN connection.
30573 @item @code{ca} (default: @code{"/etc/openvpn/ca.crt"}) (type: maybe-string)
30574 The certificate authority to check connections against.
30576 @item @code{cert} (default: @code{"/etc/openvpn/client.crt"}) (type: maybe-string)
30577 The certificate of the machine the daemon is running on. It should be
30578 signed by the authority given in @code{ca}.
30580 @item @code{key} (default: @code{"/etc/openvpn/client.key"}) (type: maybe-string)
30581 The key of the machine the daemon is running on. It must be the key
30582 whose certificate is @code{cert}.
30584 @item @code{comp-lzo?} (default: @code{#t}) (type: boolean)
30585 Whether to use the lzo compression algorithm.
30587 @item @code{persist-key?} (default: @code{#t}) (type: boolean)
30588 Don't re-read key files across SIGUSR1 or --ping-restart.
30590 @item @code{persist-tun?} (default: @code{#t}) (type: boolean)
30591 Don't close and reopen TUN/TAP device or run up/down scripts across
30592 SIGUSR1 or --ping-restart restarts.
30594 @item @code{fast-io?} (default: @code{#f}) (type: boolean)
30595 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
30596 poll/epoll/select prior to the write operation.
30598 @item @code{verbosity} (default: @code{3}) (type: number)
30601 @item @code{tls-auth} (default: @code{#f}) (type: tls-auth-client)
30602 Add an additional layer of HMAC authentication on top of the TLS control
30603 channel to protect against DoS attacks.
30605 @item @code{auth-user-pass} (type: maybe-string)
30606 Authenticate with server using username/password. The option is a file
30607 containing username/password on 2 lines. Do not use a file-like object
30608 as it would be added to the store and readable by any user.
30610 @item @code{verify-key-usage?} (default: @code{#t}) (type: key-usage)
30611 Whether to check the server certificate has server usage extension.
30613 @item @code{bind?} (default: @code{#f}) (type: bind)
30614 Bind to a specific local port number.
30616 @item @code{resolv-retry?} (default: @code{#t}) (type: resolv-retry)
30617 Retry resolving server address.
30619 @item @code{remote} (default: @code{()}) (type: openvpn-remote-list)
30620 A list of remote servers to connect to.
30622 @deftp {Data Type} openvpn-remote-configuration
30623 Available @code{openvpn-remote-configuration} fields are:
30626 @item @code{name} (default: @code{"my-server"}) (type: string)
30629 @item @code{port} (default: @code{1194}) (type: number)
30630 Port number the server listens to.
30640 @c %end of automatic openvpn-client documentation
30642 @c %automatically generated documentation
30644 @deftp {Data Type} openvpn-server-configuration
30645 Available @code{openvpn-server-configuration} fields are:
30648 @item @code{openvpn} (default: @code{openvpn}) (type: file-like)
30649 The OpenVPN package.
30651 @item @code{pid-file} (default: @code{"/var/run/openvpn/openvpn.pid"}) (type: string)
30652 The OpenVPN pid file.
30654 @item @code{proto} (default: @code{udp}) (type: proto)
30655 The protocol (UDP or TCP) used to open a channel between clients and
30658 @item @code{dev} (default: @code{tun}) (type: dev)
30659 The device type used to represent the VPN connection.
30661 @item @code{ca} (default: @code{"/etc/openvpn/ca.crt"}) (type: maybe-string)
30662 The certificate authority to check connections against.
30664 @item @code{cert} (default: @code{"/etc/openvpn/client.crt"}) (type: maybe-string)
30665 The certificate of the machine the daemon is running on. It should be
30666 signed by the authority given in @code{ca}.
30668 @item @code{key} (default: @code{"/etc/openvpn/client.key"}) (type: maybe-string)
30669 The key of the machine the daemon is running on. It must be the key
30670 whose certificate is @code{cert}.
30672 @item @code{comp-lzo?} (default: @code{#t}) (type: boolean)
30673 Whether to use the lzo compression algorithm.
30675 @item @code{persist-key?} (default: @code{#t}) (type: boolean)
30676 Don't re-read key files across SIGUSR1 or --ping-restart.
30678 @item @code{persist-tun?} (default: @code{#t}) (type: boolean)
30679 Don't close and reopen TUN/TAP device or run up/down scripts across
30680 SIGUSR1 or --ping-restart restarts.
30682 @item @code{fast-io?} (default: @code{#f}) (type: boolean)
30683 (Experimental) Optimize TUN/TAP/UDP I/O writes by avoiding a call to
30684 poll/epoll/select prior to the write operation.
30686 @item @code{verbosity} (default: @code{3}) (type: number)
30689 @item @code{tls-auth} (default: @code{#f}) (type: tls-auth-server)
30690 Add an additional layer of HMAC authentication on top of the TLS control
30691 channel to protect against DoS attacks.
30693 @item @code{port} (default: @code{1194}) (type: number)
30694 Specifies the port number on which the server listens.
30696 @item @code{server} (default: @code{"10.8.0.0 255.255.255.0"}) (type: ip-mask)
30697 An ip and mask specifying the subnet inside the virtual network.
30699 @item @code{server-ipv6} (default: @code{#f}) (type: cidr6)
30700 A CIDR notation specifying the IPv6 subnet inside the virtual network.
30702 @item @code{dh} (default: @code{"/etc/openvpn/dh2048.pem"}) (type: string)
30703 The Diffie-Hellman parameters file.
30705 @item @code{ifconfig-pool-persist} (default: @code{"/etc/openvpn/ipp.txt"}) (type: string)
30706 The file that records client IPs.
30708 @item @code{redirect-gateway?} (default: @code{#f}) (type: gateway)
30709 When true, the server will act as a gateway for its clients.
30711 @item @code{client-to-client?} (default: @code{#f}) (type: boolean)
30712 When true, clients are allowed to talk to each other inside the VPN.
30714 @item @code{keepalive} (default: @code{(10 120)}) (type: keepalive)
30715 Causes ping-like messages to be sent back and forth over the link so
30716 that each side knows when the other side has gone down. @code{keepalive}
30717 requires a pair. The first element is the period of the ping sending,
30718 and the second element is the timeout before considering the other side
30721 @item @code{max-clients} (default: @code{100}) (type: number)
30722 The maximum number of clients.
30724 @item @code{status} (default: @code{"/var/run/openvpn/status"}) (type: string)
30725 The status file. This file shows a small report on current connection.
30726 It is truncated and rewritten every minute.
30728 @item @code{client-config-dir} (default: @code{()}) (type: openvpn-ccd-list)
30729 The list of configuration for some clients.
30735 @c %end of automatic openvpn-server documentation
30737 @subheading strongSwan
30739 Currently, the strongSwan service only provides legacy-style configuration with
30740 @file{ipsec.conf} and @file{ipsec.secrets} files.
30742 @defvr {Scheme Variable} strongswan-service-type
30743 A service type for configuring strongSwan for IPsec @acronym{VPN,
30744 Virtual Private Networking}. Its value must be a
30745 @code{strongswan-configuration} record as in this example:
30748 (service strongswan-service-type
30749 (strongswan-configuration
30750 (ipsec-conf "/etc/ipsec.conf")
30751 (ipsec-secrets "/etc/ipsec.secrets")))
30756 @deftp {Data Type} strongswan-configuration
30757 Data type representing the configuration of the StrongSwan service.
30760 @item @code{strongswan}
30761 The strongSwan package to use for this service.
30763 @item @code{ipsec-conf} (default: @code{#f})
30764 The file name of your @file{ipsec.conf}. If not @code{#f}, then this and
30765 @code{ipsec-secrets} must both be strings.
30767 @item @code{ipsec-secrets} (default @code{#f})
30768 The file name of your @file{ipsec.secrets}. If not @code{#f}, then this and
30769 @code{ipsec-conf} must both be strings.
30774 @subsubheading Wireguard
30776 @defvr {Scheme Variable} wireguard-service-type
30777 A service type for a Wireguard tunnel interface. Its value must be a
30778 @code{wireguard-configuration} record as in this example:
30781 (service wireguard-service-type
30782 (wireguard-configuration
30787 (endpoint "my.wireguard.com:51820")
30788 (public-key "hzpKg9X1yqu1axN6iJp0mWf6BZGo8m1wteKwtTmDGF4=")
30789 (allowed-ips '("10.0.0.2/32")))))))
30794 @deftp {Data Type} wireguard-configuration
30795 Data type representing the configuration of the Wireguard service.
30798 @item @code{wireguard}
30799 The wireguard package to use for this service.
30801 @item @code{interface} (default: @code{"wg0"})
30802 The interface name for the VPN.
30804 @item @code{addresses} (default: @code{'("10.0.0.1/32")})
30805 The IP addresses to be assigned to the above interface.
30807 @item @code{port} (default: @code{51820})
30808 The port on which to listen for incoming connections.
30810 @item @code{dns} (default: @code{#f})
30811 The DNS server(s) to announce to VPN clients via DHCP.
30813 @item @code{private-key} (default: @code{"/etc/wireguard/private.key"})
30814 The private key file for the interface. It is automatically generated if
30815 the file does not exist.
30817 @item @code{peers} (default: @code{'()})
30818 The authorized peers on this interface. This is a list of
30819 @var{wireguard-peer} records.
30824 @deftp {Data Type} wireguard-peer
30825 Data type representing a Wireguard peer attached to a given interface.
30831 @item @code{endpoint} (default: @code{#f})
30832 The optional endpoint for the peer, such as
30833 @code{"demo.wireguard.com:51820"}.
30835 @item @code{public-key}
30836 The peer public-key represented as a base64 string.
30838 @item @code{allowed-ips}
30839 A list of IP addresses from which incoming traffic for this peer is
30840 allowed and to which incoming traffic for this peer is directed.
30842 @item @code{keep-alive} (default: @code{#f})
30843 An optional time interval in seconds. A packet will be sent to the
30844 server endpoint once per time interval. This helps receiving
30845 incoming connections from this peer when you are behind a NAT or
30851 @node Network File System
30852 @subsection Network File System
30855 The @code{(gnu services nfs)} module provides the following services,
30856 which are most commonly used in relation to mounting or exporting
30857 directory trees as @dfn{network file systems} (NFS).
30859 While it is possible to use the individual components that together make
30860 up a Network File System service, we recommended to configure an NFS
30861 server with the @code{nfs-service-type}.
30863 @subsubheading NFS Service
30864 @cindex NFS, server
30866 The NFS service takes care of setting up all NFS component services,
30867 kernel configuration file systems, and installs configuration files in
30868 the locations that NFS expects.
30870 @defvr {Scheme Variable} nfs-service-type
30871 A service type for a complete NFS server.
30874 @deftp {Data Type} nfs-configuration
30875 This data type represents the configuration of the NFS service and all
30878 It has the following parameters:
30880 @item @code{nfs-utils} (default: @code{nfs-utils})
30881 The nfs-utils package to use.
30883 @item @code{nfs-versions} (default: @code{'("4.2" "4.1" "4.0")})
30884 If a list of string values is provided, the @command{rpc.nfsd} daemon
30885 will be limited to supporting the given versions of the NFS protocol.
30887 @item @code{exports} (default: @code{'()})
30888 This is a list of directories the NFS server should export. Each entry
30889 is a list consisting of two elements: a directory name and a string
30890 containing all options. This is an example in which the directory
30891 @file{/export} is served to all NFS clients as a read-only share:
30897 "*(ro,insecure,no_subtree_check,crossmnt,fsid=0)"))))
30900 @item @code{rpcmountd-port} (default: @code{#f})
30901 The network port that the @command{rpc.mountd} daemon should use.
30903 @item @code{rpcstatd-port} (default: @code{#f})
30904 The network port that the @command{rpc.statd} daemon should use.
30906 @item @code{rpcbind} (default: @code{rpcbind})
30907 The rpcbind package to use.
30909 @item @code{idmap-domain} (default: @code{"localdomain"})
30910 The local NFSv4 domain name.
30912 @item @code{nfsd-port} (default: @code{2049})
30913 The network port that the @command{nfsd} daemon should use.
30915 @item @code{nfsd-threads} (default: @code{8})
30916 The number of threads used by the @command{nfsd} daemon.
30918 @item @code{nfsd-tcp?} (default: @code{#t})
30919 Whether the @command{nfsd} daemon should listen on a TCP socket.
30921 @item @code{nfsd-udp?} (default: @code{#f})
30922 Whether the @command{nfsd} daemon should listen on a UDP socket.
30924 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
30925 The directory where the pipefs file system is mounted.
30927 @item @code{debug} (default: @code{'()"})
30928 A list of subsystems for which debugging output should be enabled. This
30929 is a list of symbols. Any of these symbols are valid: @code{nfsd},
30930 @code{nfs}, @code{rpc}, @code{idmap}, @code{statd}, or @code{mountd}.
30934 If you don't need a complete NFS service or prefer to build it yourself
30935 you can use the individual component services that are documented below.
30937 @subsubheading RPC Bind Service
30940 The RPC Bind service provides a facility to map program numbers into
30941 universal addresses.
30942 Many NFS related services use this facility. Hence it is automatically
30943 started when a dependent service starts.
30945 @defvr {Scheme Variable} rpcbind-service-type
30946 A service type for the RPC portmapper daemon.
30950 @deftp {Data Type} rpcbind-configuration
30951 Data type representing the configuration of the RPC Bind Service.
30952 This type has the following parameters:
30954 @item @code{rpcbind} (default: @code{rpcbind})
30955 The rpcbind package to use.
30957 @item @code{warm-start?} (default: @code{#t})
30958 If this parameter is @code{#t}, then the daemon will read a
30959 state file on startup thus reloading state information saved by a previous
30965 @subsubheading Pipefs Pseudo File System
30969 The pipefs file system is used to transfer NFS related data
30970 between the kernel and user space programs.
30972 @defvr {Scheme Variable} pipefs-service-type
30973 A service type for the pipefs pseudo file system.
30976 @deftp {Data Type} pipefs-configuration
30977 Data type representing the configuration of the pipefs pseudo file system service.
30978 This type has the following parameters:
30980 @item @code{mount-point} (default: @code{"/var/lib/nfs/rpc_pipefs"})
30981 The directory to which the file system is to be attached.
30986 @subsubheading GSS Daemon Service
30989 @cindex global security system
30991 The @dfn{global security system} (GSS) daemon provides strong security for RPC
30993 Before exchanging RPC requests an RPC client must establish a security
30994 context. Typically this is done using the Kerberos command @command{kinit}
30995 or automatically at login time using PAM services (@pxref{Kerberos Services}).
30997 @defvr {Scheme Variable} gss-service-type
30998 A service type for the Global Security System (GSS) daemon.
31001 @deftp {Data Type} gss-configuration
31002 Data type representing the configuration of the GSS daemon service.
31003 This type has the following parameters:
31005 @item @code{nfs-utils} (default: @code{nfs-utils})
31006 The package in which the @command{rpc.gssd} command is to be found.
31008 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31009 The directory where the pipefs file system is mounted.
31015 @subsubheading IDMAP Daemon Service
31017 @cindex name mapper
31019 The idmap daemon service provides mapping between user IDs and user names.
31020 Typically it is required in order to access file systems mounted via NFSv4.
31022 @defvr {Scheme Variable} idmap-service-type
31023 A service type for the Identity Mapper (IDMAP) daemon.
31026 @deftp {Data Type} idmap-configuration
31027 Data type representing the configuration of the IDMAP daemon service.
31028 This type has the following parameters:
31030 @item @code{nfs-utils} (default: @code{nfs-utils})
31031 The package in which the @command{rpc.idmapd} command is to be found.
31033 @item @code{pipefs-directory} (default: @code{"/var/lib/nfs/rpc_pipefs"})
31034 The directory where the pipefs file system is mounted.
31036 @item @code{domain} (default: @code{#f})
31037 The local NFSv4 domain name.
31038 This must be a string or @code{#f}.
31039 If it is @code{#f} then the daemon will use the host's fully qualified domain name.
31041 @item @code{verbosity} (default: @code{0})
31042 The verbosity level of the daemon.
31047 @node Continuous Integration
31048 @subsection Continuous Integration
31050 @cindex continuous integration
31051 @uref{https://guix.gnu.org/cuirass/, Cuirass} is a continuous
31052 integration tool for Guix. It can be used both for development and for
31053 providing substitutes to others (@pxref{Substitutes}).
31055 The @code{(gnu services cuirass)} module provides the following service.
31057 @defvr {Scheme Procedure} cuirass-service-type
31058 The type of the Cuirass service. Its value must be a
31059 @code{cuirass-configuration} object, as described below.
31062 To add build jobs, you have to set the @code{specifications} field of
31063 the configuration. For instance, the following example will build all
31064 the packages provided by the @code{my-channel} channel.
31067 (define %cuirass-specs
31068 #~(list (specification
31069 (name "my-channel")
31070 (build '(channels my-channel))
31074 (url "https://my-channel.git"))
31075 %default-channels)))))
31077 (service cuirass-service-type
31078 (cuirass-configuration
31079 (specifications %cuirass-specs)))
31082 To build the @code{linux-libre} package defined by the default Guix
31083 channel, one can use the following configuration.
31086 (define %cuirass-specs
31087 #~(list (specification
31089 (build '(packages "linux-libre")))))
31091 (service cuirass-service-type
31092 (cuirass-configuration
31093 (specifications %cuirass-specs)))
31096 The other configuration possibilities, as well as the specification
31097 record itself are described in the Cuirass manual
31098 (@pxref{Specifications,,, cuirass, Cuirass}).
31100 While information related to build jobs is located directly in the
31101 specifications, global settings for the @command{cuirass} process are
31102 accessible in other @code{cuirass-configuration} fields.
31104 @deftp {Data Type} cuirass-configuration
31105 Data type representing the configuration of Cuirass.
31108 @item @code{cuirass} (default: @code{cuirass})
31109 The Cuirass package to use.
31111 @item @code{log-file} (default: @code{"/var/log/cuirass.log"})
31112 Location of the log file.
31114 @item @code{web-log-file} (default: @code{"/var/log/cuirass-web.log"})
31115 Location of the log file used by the web interface.
31117 @item @code{cache-directory} (default: @code{"/var/cache/cuirass"})
31118 Location of the repository cache.
31120 @item @code{user} (default: @code{"cuirass"})
31121 Owner of the @code{cuirass} process.
31123 @item @code{group} (default: @code{"cuirass"})
31124 Owner's group of the @code{cuirass} process.
31126 @item @code{interval} (default: @code{60})
31127 Number of seconds between the poll of the repositories followed by the
31130 @item @code{parameters} (default: @code{#f})
31131 Read parameters from the given @var{parameters} file. The supported
31132 parameters are described here (@pxref{Parameters,,, cuirass, Cuirass}).
31134 @item @code{remote-server} (default: @code{#f})
31135 A @code{cuirass-remote-server-configuration} record to use the build
31136 remote mechanism or @code{#f} to use the default build mechanism.
31138 @item @code{database} (default: @code{"dbname=cuirass host=/var/run/postgresql"})
31139 Use @var{database} as the database containing the jobs and the past
31140 build results. Since Cuirass uses PostgreSQL as a database engine,
31141 @var{database} must be a string such as @code{"dbname=cuirass
31144 @item @code{port} (default: @code{8081})
31145 Port number used by the HTTP server.
31147 @item @code{host} (default: @code{"localhost"})
31148 Listen on the network interface for @var{host}. The default is to
31149 accept connections from localhost.
31151 @item @code{specifications} (default: @code{#~'()})
31152 A gexp (@pxref{G-Expressions}) that evaluates to a list of
31153 specifications records. The specification record is described in the
31154 Cuirass manual (@pxref{Specifications,,, cuirass, Cuirass}).
31156 @item @code{use-substitutes?} (default: @code{#f})
31157 This allows using substitutes to avoid building every dependencies of a job
31160 @item @code{one-shot?} (default: @code{#f})
31161 Only evaluate specifications and build derivations once.
31163 @item @code{fallback?} (default: @code{#f})
31164 When substituting a pre-built binary fails, fall back to building
31167 @item @code{extra-options} (default: @code{'()})
31168 Extra options to pass when running the Cuirass processes.
31173 @cindex remote build
31174 @subsubheading Cuirass remote building
31176 Cuirass supports two mechanisms to build derivations.
31179 @item Using the local Guix daemon.
31180 This is the default build mechanism. Once the build jobs are
31181 evaluated, they are sent to the local Guix daemon. Cuirass then
31182 listens to the Guix daemon output to detect the various build events.
31184 @item Using the remote build mechanism.
31185 The build jobs are not submitted to the local Guix daemon. Instead, a
31186 remote server dispatches build requests to the connect remote workers,
31187 according to the build priorities.
31191 To enable this build mode a @code{cuirass-remote-server-configuration}
31192 record must be passed as @code{remote-server} argument of the
31193 @code{cuirass-configuration} record. The
31194 @code{cuirass-remote-server-configuration} record is described below.
31196 This build mode scales way better than the default build mode. This is
31197 the build mode that is used on the GNU Guix build farm at
31198 @url{https://ci.guix.gnu.org}. It should be preferred when using
31199 Cuirass to build large amount of packages.
31201 @deftp {Data Type} cuirass-remote-server-configuration
31202 Data type representing the configuration of the Cuirass remote-server.
31205 @item @code{backend-port} (default: @code{5555})
31206 The TCP port for communicating with @code{remote-worker} processes
31207 using ZMQ. It defaults to @code{5555}.
31209 @item @code{log-port} (default: @code{5556})
31210 The TCP port of the log server. It defaults to @code{5556}.
31212 @item @code{publish-port} (default: @code{5557})
31213 The TCP port of the publish server. It defaults to @code{5557}.
31215 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-server.log"})
31216 Location of the log file.
31218 @item @code{cache} (default: @code{"/var/cache/cuirass/remote"})
31219 Use @var{cache} directory to cache build log files.
31221 @item @code{trigger-url} (default: @code{#f})
31222 Once a substitute is successfully fetched, trigger substitute baking at
31225 @item @code{publish?} (default: @code{#t})
31226 If set to false, do not start a publish server and ignore the
31227 @code{publish-port} argument. This can be useful if there is already a
31228 standalone publish server standing next to the remote server.
31230 @item @code{public-key}
31231 @item @code{private-key}
31232 Use the specific @var{file}s as the public/private key pair used to sign
31233 the store items being published.
31238 At least one remote worker must also be started on any machine of the
31239 local network to actually perform the builds and report their status.
31241 @deftp {Data Type} cuirass-remote-worker-configuration
31242 Data type representing the configuration of the Cuirass remote-worker.
31245 @item @code{cuirass} (default: @code{cuirass})
31246 The Cuirass package to use.
31248 @item @code{workers} (default: @code{1})
31249 Start @var{workers} parallel workers.
31251 @item @code{server} (default: @code{#f})
31252 Do not use Avahi discovery and connect to the given @code{server} IP
31255 @item @code{systems} (default: @code{(list (%current-system))})
31256 Only request builds for the given @var{systems}.
31258 @item @code{log-file} (default: @code{"/var/log/cuirass-remote-worker.log"})
31259 Location of the log file.
31261 @item @code{publish-port} (default: @code{5558})
31262 The TCP port of the publish server. It defaults to @code{5558}.
31264 @item @code{substitute-urls} (default: @code{%default-substitute-urls})
31265 The list of URLs where to look for substitutes by default.
31267 @item @code{public-key}
31268 @item @code{private-key}
31269 Use the specific @var{file}s as the public/private key pair used to sign
31270 the store items being published.
31275 @subsubheading Laminar
31277 @uref{https://laminar.ohwg.net/, Laminar} is a lightweight and modular
31278 Continuous Integration service. It doesn't have a configuration web UI
31279 instead uses version-controllable configuration files and scripts.
31281 Laminar encourages the use of existing tools such as bash and cron
31282 instead of reinventing them.
31284 @defvr {Scheme Procedure} laminar-service-type
31285 The type of the Laminar service. Its value must be a
31286 @code{laminar-configuration} object, as described below.
31288 All configuration values have defaults, a minimal configuration to get
31289 Laminar running is shown below. By default, the web interface is
31290 available on port 8080.
31293 (service laminar-service-type)
31297 @deftp {Data Type} laminar-configuration
31298 Data type representing the configuration of Laminar.
31301 @item @code{laminar} (default: @code{laminar})
31302 The Laminar package to use.
31304 @item @code{home-directory} (default: @code{"/var/lib/laminar"})
31305 The directory for job configurations and run directories.
31307 @item @code{bind-http} (default: @code{"*:8080"})
31308 The interface/port or unix socket on which laminard should listen for
31309 incoming connections to the web frontend.
31311 @item @code{bind-rpc} (default: @code{"unix-abstract:laminar"})
31312 The interface/port or unix socket on which laminard should listen for
31313 incoming commands such as build triggers.
31315 @item @code{title} (default: @code{"Laminar"})
31316 The page title to show in the web frontend.
31318 @item @code{keep-rundirs} (default: @code{0})
31319 Set to an integer defining how many rundirs to keep per job. The
31320 lowest-numbered ones will be deleted. The default is 0, meaning all run
31321 dirs will be immediately deleted.
31323 @item @code{archive-url} (default: @code{#f})
31324 The web frontend served by laminard will use this URL to form links to
31325 artefacts archived jobs.
31327 @item @code{base-url} (default: @code{#f})
31328 Base URL to use for links to laminar itself.
31333 @node Power Management Services
31334 @subsection Power Management Services
31337 @cindex power management with TLP
31338 @subsubheading TLP daemon
31340 The @code{(gnu services pm)} module provides a Guix service definition
31341 for the Linux power management tool TLP.
31343 TLP enables various powersaving modes in userspace and kernel.
31344 Contrary to @code{upower-service}, it is not a passive,
31345 monitoring tool, as it will apply custom settings each time a new power
31346 source is detected. More information can be found at
31347 @uref{https://linrunner.de/en/tlp/tlp.html, TLP home page}.
31349 @deffn {Scheme Variable} tlp-service-type
31350 The service type for the TLP tool. The default settings are optimised
31351 for battery life on most systems, but you can tweak them to your heart's
31352 content by adding a valid @code{tlp-configuration}:
31354 (service tlp-service-type
31356 (cpu-scaling-governor-on-ac (list "performance"))
31357 (sched-powersave-on-bat? #t)))
31361 Each parameter definition is preceded by its type; for example,
31362 @samp{boolean foo} indicates that the @code{foo} parameter should be
31363 specified as a boolean. Types starting with @code{maybe-} denote
31364 parameters that won't show up in TLP config file when their value is
31365 left unset, or is explicitly set to the @code{'unset} value.
31367 @c The following documentation was initially generated by
31368 @c (generate-tlp-documentation) in (gnu services pm). Manually maintained
31369 @c documentation is better, so we shouldn't hesitate to edit below as
31370 @c needed. However if the change you want to make to this documentation
31371 @c can be done in an automated way, it's probably easier to change
31372 @c (generate-documentation) than to make it below and have to deal with
31373 @c the churn as TLP updates.
31375 Available @code{tlp-configuration} fields are:
31377 @deftypevr {@code{tlp-configuration} parameter} package tlp
31382 @deftypevr {@code{tlp-configuration} parameter} boolean tlp-enable?
31383 Set to true if you wish to enable TLP.
31385 Defaults to @samp{#t}.
31389 @deftypevr {@code{tlp-configuration} parameter} string tlp-default-mode
31390 Default mode when no power supply can be detected. Alternatives are AC
31393 Defaults to @samp{"AC"}.
31397 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-ac
31398 Number of seconds Linux kernel has to wait after the disk goes idle,
31399 before syncing on AC.
31401 Defaults to @samp{0}.
31405 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer disk-idle-secs-on-bat
31406 Same as @code{disk-idle-ac} but on BAT mode.
31408 Defaults to @samp{2}.
31412 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-ac
31413 Dirty pages flushing periodicity, expressed in seconds.
31415 Defaults to @samp{15}.
31419 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer max-lost-work-secs-on-bat
31420 Same as @code{max-lost-work-secs-on-ac} but on BAT mode.
31422 Defaults to @samp{60}.
31426 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-ac
31427 CPU frequency scaling governor on AC mode. With intel_pstate driver,
31428 alternatives are powersave and performance. With acpi-cpufreq driver,
31429 alternatives are ondemand, powersave, performance and conservative.
31431 Defaults to @samp{disabled}.
31435 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list cpu-scaling-governor-on-bat
31436 Same as @code{cpu-scaling-governor-on-ac} but on BAT mode.
31438 Defaults to @samp{disabled}.
31442 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-ac
31443 Set the min available frequency for the scaling governor on AC.
31445 Defaults to @samp{disabled}.
31449 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-ac
31450 Set the max available frequency for the scaling governor on AC.
31452 Defaults to @samp{disabled}.
31456 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-min-freq-on-bat
31457 Set the min available frequency for the scaling governor on BAT.
31459 Defaults to @samp{disabled}.
31463 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-scaling-max-freq-on-bat
31464 Set the max available frequency for the scaling governor on BAT.
31466 Defaults to @samp{disabled}.
31470 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-ac
31471 Limit the min P-state to control the power dissipation of the CPU, in AC
31472 mode. Values are stated as a percentage of the available performance.
31474 Defaults to @samp{disabled}.
31478 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-ac
31479 Limit the max P-state to control the power dissipation of the CPU, in AC
31480 mode. Values are stated as a percentage of the available performance.
31482 Defaults to @samp{disabled}.
31486 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-min-perf-on-bat
31487 Same as @code{cpu-min-perf-on-ac} on BAT mode.
31489 Defaults to @samp{disabled}.
31493 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer cpu-max-perf-on-bat
31494 Same as @code{cpu-max-perf-on-ac} on BAT mode.
31496 Defaults to @samp{disabled}.
31500 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-ac?
31501 Enable CPU turbo boost feature on AC mode.
31503 Defaults to @samp{disabled}.
31507 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean cpu-boost-on-bat?
31508 Same as @code{cpu-boost-on-ac?} on BAT mode.
31510 Defaults to @samp{disabled}.
31514 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-ac?
31515 Allow Linux kernel to minimize the number of CPU cores/hyper-threads
31516 used under light load conditions.
31518 Defaults to @samp{#f}.
31522 @deftypevr {@code{tlp-configuration} parameter} boolean sched-powersave-on-bat?
31523 Same as @code{sched-powersave-on-ac?} but on BAT mode.
31525 Defaults to @samp{#t}.
31529 @deftypevr {@code{tlp-configuration} parameter} boolean nmi-watchdog?
31530 Enable Linux kernel NMI watchdog.
31532 Defaults to @samp{#f}.
31536 @deftypevr {@code{tlp-configuration} parameter} maybe-string phc-controls
31537 For Linux kernels with PHC patch applied, change CPU voltages. An
31538 example value would be @samp{"F:V F:V F:V F:V"}.
31540 Defaults to @samp{disabled}.
31544 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-ac
31545 Set CPU performance versus energy saving policy on AC@. Alternatives are
31546 performance, normal, powersave.
31548 Defaults to @samp{"performance"}.
31552 @deftypevr {@code{tlp-configuration} parameter} string energy-perf-policy-on-bat
31553 Same as @code{energy-perf-policy-ac} but on BAT mode.
31555 Defaults to @samp{"powersave"}.
31559 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disks-devices
31564 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-ac
31565 Hard disk advanced power management level.
31569 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list disk-apm-level-on-bat
31570 Same as @code{disk-apm-bat} but on BAT mode.
31574 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-ac
31575 Hard disk spin down timeout. One value has to be specified for each
31576 declared hard disk.
31578 Defaults to @samp{disabled}.
31582 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-spindown-timeout-on-bat
31583 Same as @code{disk-spindown-timeout-on-ac} but on BAT mode.
31585 Defaults to @samp{disabled}.
31589 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list disk-iosched
31590 Select IO scheduler for disk devices. One value has to be specified for
31591 each declared hard disk. Example alternatives are cfq, deadline and
31594 Defaults to @samp{disabled}.
31598 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-ac
31599 SATA aggressive link power management (ALPM) level. Alternatives are
31600 min_power, medium_power, max_performance.
31602 Defaults to @samp{"max_performance"}.
31606 @deftypevr {@code{tlp-configuration} parameter} string sata-linkpwr-on-bat
31607 Same as @code{sata-linkpwr-ac} but on BAT mode.
31609 Defaults to @samp{"min_power"}.
31613 @deftypevr {@code{tlp-configuration} parameter} maybe-string sata-linkpwr-blacklist
31614 Exclude specified SATA host devices for link power management.
31616 Defaults to @samp{disabled}.
31620 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-ac?
31621 Enable Runtime Power Management for AHCI controller and disks on AC
31624 Defaults to @samp{disabled}.
31628 @deftypevr {@code{tlp-configuration} parameter} maybe-on-off-boolean ahci-runtime-pm-on-bat?
31629 Same as @code{ahci-runtime-pm-on-ac} on BAT mode.
31631 Defaults to @samp{disabled}.
31635 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer ahci-runtime-pm-timeout
31636 Seconds of inactivity before disk is suspended.
31638 Defaults to @samp{15}.
31642 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-ac
31643 PCI Express Active State Power Management level. Alternatives are
31644 default, performance, powersave.
31646 Defaults to @samp{"performance"}.
31650 @deftypevr {@code{tlp-configuration} parameter} string pcie-aspm-on-bat
31651 Same as @code{pcie-aspm-ac} but on BAT mode.
31653 Defaults to @samp{"powersave"}.
31657 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat0
31658 Percentage when battery 0 should begin charging. Only supported on some laptops.
31660 Defaults to @samp{disabled}.
31664 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat0
31665 Percentage when battery 0 should stop charging. Only supported on some laptops.
31667 Defaults to @samp{disabled}.
31671 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer start-charge-thresh-bat1
31672 Percentage when battery 1 should begin charging. Only supported on some laptops.
31674 Defaults to @samp{disabled}.
31678 @deftypevr {@code{tlp-configuration} parameter} maybe-non-negative-integer stop-charge-thresh-bat1
31679 Percentage when battery 1 should stop charging. Only supported on some laptops.
31681 Defaults to @samp{disabled}.
31685 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-ac
31686 Radeon graphics clock speed level. Alternatives are low, mid, high,
31689 Defaults to @samp{"high"}.
31693 @deftypevr {@code{tlp-configuration} parameter} string radeon-power-profile-on-bat
31694 Same as @code{radeon-power-ac} but on BAT mode.
31696 Defaults to @samp{"low"}.
31700 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-ac
31701 Radeon dynamic power management method (DPM). Alternatives are battery,
31704 Defaults to @samp{"performance"}.
31708 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-state-on-bat
31709 Same as @code{radeon-dpm-state-ac} but on BAT mode.
31711 Defaults to @samp{"battery"}.
31715 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-ac
31716 Radeon DPM performance level. Alternatives are auto, low, high.
31718 Defaults to @samp{"auto"}.
31722 @deftypevr {@code{tlp-configuration} parameter} string radeon-dpm-perf-level-on-bat
31723 Same as @code{radeon-dpm-perf-ac} but on BAT mode.
31725 Defaults to @samp{"auto"}.
31729 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-ac?
31730 Wifi power saving mode.
31732 Defaults to @samp{#f}.
31736 @deftypevr {@code{tlp-configuration} parameter} on-off-boolean wifi-pwr-on-bat?
31737 Same as @code{wifi-power-ac?} but on BAT mode.
31739 Defaults to @samp{#t}.
31743 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean wol-disable?
31744 Disable wake on LAN.
31746 Defaults to @samp{#t}.
31750 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-ac
31751 Timeout duration in seconds before activating audio power saving on
31752 Intel HDA and AC97 devices. A value of 0 disables power saving.
31754 Defaults to @samp{0}.
31758 @deftypevr {@code{tlp-configuration} parameter} non-negative-integer sound-power-save-on-bat
31759 Same as @code{sound-powersave-ac} but on BAT mode.
31761 Defaults to @samp{1}.
31765 @deftypevr {@code{tlp-configuration} parameter} y-n-boolean sound-power-save-controller?
31766 Disable controller in powersaving mode on Intel HDA devices.
31768 Defaults to @samp{#t}.
31772 @deftypevr {@code{tlp-configuration} parameter} boolean bay-poweroff-on-bat?
31773 Enable optical drive in UltraBay/MediaBay on BAT mode. Drive can be
31774 powered on again by releasing (and reinserting) the eject lever or by
31775 pressing the disc eject button on newer models.
31777 Defaults to @samp{#f}.
31781 @deftypevr {@code{tlp-configuration} parameter} string bay-device
31782 Name of the optical drive device to power off.
31784 Defaults to @samp{"sr0"}.
31788 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-ac
31789 Runtime Power Management for PCI(e) bus devices. Alternatives are on
31792 Defaults to @samp{"on"}.
31796 @deftypevr {@code{tlp-configuration} parameter} string runtime-pm-on-bat
31797 Same as @code{runtime-pm-ac} but on BAT mode.
31799 Defaults to @samp{"auto"}.
31803 @deftypevr {@code{tlp-configuration} parameter} boolean runtime-pm-all?
31804 Runtime Power Management for all PCI(e) bus devices, except blacklisted
31807 Defaults to @samp{#t}.
31811 @deftypevr {@code{tlp-configuration} parameter} maybe-space-separated-string-list runtime-pm-blacklist
31812 Exclude specified PCI(e) device addresses from Runtime Power Management.
31814 Defaults to @samp{disabled}.
31818 @deftypevr {@code{tlp-configuration} parameter} space-separated-string-list runtime-pm-driver-blacklist
31819 Exclude PCI(e) devices assigned to the specified drivers from Runtime
31824 @deftypevr {@code{tlp-configuration} parameter} boolean usb-autosuspend?
31825 Enable USB autosuspend feature.
31827 Defaults to @samp{#t}.
31831 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-blacklist
31832 Exclude specified devices from USB autosuspend.
31834 Defaults to @samp{disabled}.
31838 @deftypevr {@code{tlp-configuration} parameter} boolean usb-blacklist-wwan?
31839 Exclude WWAN devices from USB autosuspend.
31841 Defaults to @samp{#t}.
31845 @deftypevr {@code{tlp-configuration} parameter} maybe-string usb-whitelist
31846 Include specified devices into USB autosuspend, even if they are already
31847 excluded by the driver or via @code{usb-blacklist-wwan?}.
31849 Defaults to @samp{disabled}.
31853 @deftypevr {@code{tlp-configuration} parameter} maybe-boolean usb-autosuspend-disable-on-shutdown?
31854 Enable USB autosuspend before shutdown.
31856 Defaults to @samp{disabled}.
31860 @deftypevr {@code{tlp-configuration} parameter} boolean restore-device-state-on-startup?
31861 Restore radio device state (bluetooth, wifi, wwan) from previous
31862 shutdown on system startup.
31864 Defaults to @samp{#f}.
31869 @cindex CPU frequency scaling with thermald
31870 @subsubheading Thermald daemon
31872 The @code{(gnu services pm)} module provides an interface to
31873 thermald, a CPU frequency scaling service which helps prevent overheating.
31875 @defvr {Scheme Variable} thermald-service-type
31876 This is the service type for
31877 @uref{https://01.org/linux-thermal-daemon/, thermald}, the Linux
31878 Thermal Daemon, which is responsible for controlling the thermal state
31879 of processors and preventing overheating.
31882 @deftp {Data Type} thermald-configuration
31883 Data type representing the configuration of @code{thermald-service-type}.
31886 @item @code{adaptive?} (default: @code{#f})
31887 Use @acronym{DPTF, Dynamic Power and Thermal Framework} adaptive tables
31890 @item @code{ignore-cpuid-check?} (default: @code{#f})
31891 Ignore cpuid check for supported CPU models.
31893 @item @code{thermald} (default: @var{thermald})
31894 Package object of thermald.
31899 @node Audio Services
31900 @subsection Audio Services
31902 The @code{(gnu services audio)} module provides a service to start MPD
31903 (the Music Player Daemon).
31906 @subsubheading Music Player Daemon
31908 The Music Player Daemon (MPD) is a service that can play music while
31909 being controlled from the local machine or over the network by a variety
31912 The following example shows how one might run @code{mpd} as user
31913 @code{"bob"} on port @code{6666}. It uses pulseaudio for output.
31916 (service mpd-service-type
31922 @defvr {Scheme Variable} mpd-service-type
31923 The service type for @command{mpd}
31926 @deftp {Data Type} mpd-configuration
31927 Data type representing the configuration of @command{mpd}.
31930 @item @code{user} (default: @code{"mpd"})
31931 The user to run mpd as.
31933 @item @code{music-dir} (default: @code{"~/Music"})
31934 The directory to scan for music files.
31936 @item @code{playlist-dir} (default: @code{"~/.mpd/playlists"})
31937 The directory to store playlists.
31939 @item @code{db-file} (default: @code{"~/.mpd/tag_cache"})
31940 The location of the music database.
31942 @item @code{state-file} (default: @code{"~/.mpd/state"})
31943 The location of the file that stores current MPD's state.
31945 @item @code{sticker-file} (default: @code{"~/.mpd/sticker.sql"})
31946 The location of the sticker database.
31948 @item @code{port} (default: @code{"6600"})
31949 The port to run mpd on.
31951 @item @code{address} (default: @code{"any"})
31952 The address that mpd will bind to. To use a Unix domain socket,
31953 an absolute path can be specified here.
31955 @item @code{outputs} (default: @code{"(list (mpd-output))"})
31956 The audio outputs that MPD can use. By default this is a single output using pulseaudio.
31961 @deftp {Data Type} mpd-output
31962 Data type representing an @command{mpd} audio output.
31965 @item @code{name} (default: @code{"MPD"})
31966 The name of the audio output.
31968 @item @code{type} (default: @code{"pulse"})
31969 The type of audio output.
31971 @item @code{enabled?} (default: @code{#t})
31972 Specifies whether this audio output is enabled when MPD is started. By
31973 default, all audio outputs are enabled. This is just the default
31974 setting when there is no state file; with a state file, the previous
31977 @item @code{tags?} (default: @code{#t})
31978 If set to @code{#f}, then MPD will not send tags to this output. This
31979 is only useful for output plugins that can receive tags, for example the
31980 @code{httpd} output plugin.
31982 @item @code{always-on?} (default: @code{#f})
31983 If set to @code{#t}, then MPD attempts to keep this audio output always
31984 open. This may be useful for streaming servers, when you don’t want to
31985 disconnect all listeners even when playback is accidentally stopped.
31987 @item @code{mixer-type}
31988 This field accepts a symbol that specifies which mixer should be used
31989 for this audio output: the @code{hardware} mixer, the @code{software}
31990 mixer, the @code{null} mixer (allows setting the volume, but with no
31991 effect; this can be used as a trick to implement an external mixer
31992 External Mixer) or no mixer (@code{none}).
31994 @item @code{extra-options} (default: @code{'()})
31995 An association list of option symbols to string values to be appended to
31996 the audio output configuration.
32001 The following example shows a configuration of @code{mpd} that provides
32002 an HTTP audio streaming output.
32005 (service mpd-service-type
32013 `((encoder . "vorbis")
32014 (port . "8080"))))))))
32018 @node Virtualization Services
32019 @subsection Virtualization Services
32021 The @code{(gnu services virtualization)} module provides services for
32022 the libvirt and virtlog daemons, as well as other virtualization-related
32025 @subsubheading Libvirt daemon
32027 @code{libvirtd} is the server side daemon component of the libvirt
32028 virtualization management system. This daemon runs on host servers
32029 and performs required management tasks for virtualized guests.
32031 @deffn {Scheme Variable} libvirt-service-type
32032 This is the type of the @uref{https://libvirt.org, libvirt daemon}.
32033 Its value must be a @code{libvirt-configuration}.
32036 (service libvirt-service-type
32037 (libvirt-configuration
32038 (unix-sock-group "libvirt")
32039 (tls-port "16555")))
32043 @c Auto-generated with (generate-libvirt-documentation)
32044 Available @code{libvirt-configuration} fields are:
32046 @deftypevr {@code{libvirt-configuration} parameter} package libvirt
32051 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tls?
32052 Flag listening for secure TLS connections on the public TCP/IP port.
32053 You must set @code{listen} for this to have any effect.
32055 It is necessary to setup a CA and issue server certificates before using
32058 Defaults to @samp{#t}.
32062 @deftypevr {@code{libvirt-configuration} parameter} boolean listen-tcp?
32063 Listen for unencrypted TCP connections on the public TCP/IP port. You must
32064 set @code{listen} for this to have any effect.
32066 Using the TCP socket requires SASL authentication by default. Only SASL
32067 mechanisms which support data encryption are allowed. This is
32068 DIGEST_MD5 and GSSAPI (Kerberos5).
32070 Defaults to @samp{#f}.
32074 @deftypevr {@code{libvirt-configuration} parameter} string tls-port
32075 Port for accepting secure TLS connections. This can be a port number,
32078 Defaults to @samp{"16514"}.
32082 @deftypevr {@code{libvirt-configuration} parameter} string tcp-port
32083 Port for accepting insecure TCP connections. This can be a port number,
32086 Defaults to @samp{"16509"}.
32090 @deftypevr {@code{libvirt-configuration} parameter} string listen-addr
32091 IP address or hostname used for client connections.
32093 Defaults to @samp{"0.0.0.0"}.
32097 @deftypevr {@code{libvirt-configuration} parameter} boolean mdns-adv?
32098 Flag toggling mDNS advertisement of the libvirt service.
32100 Alternatively can disable for all services on a host by stopping the
32103 Defaults to @samp{#f}.
32107 @deftypevr {@code{libvirt-configuration} parameter} string mdns-name
32108 Default mDNS advertisement name. This must be unique on the immediate
32111 Defaults to @samp{"Virtualization Host <hostname>"}.
32115 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-group
32116 UNIX domain socket group ownership. This can be used to allow a
32117 'trusted' set of users access to management capabilities without
32120 Defaults to @samp{"root"}.
32124 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-ro-perms
32125 UNIX socket permissions for the R/O socket. This is used for monitoring
32128 Defaults to @samp{"0777"}.
32132 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-rw-perms
32133 UNIX socket permissions for the R/W socket. Default allows only root.
32134 If PolicyKit is enabled on the socket, the default will change to allow
32135 everyone (eg, 0777)
32137 Defaults to @samp{"0770"}.
32141 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-admin-perms
32142 UNIX socket permissions for the admin socket. Default allows only owner
32143 (root), do not change it unless you are sure to whom you are exposing
32146 Defaults to @samp{"0777"}.
32150 @deftypevr {@code{libvirt-configuration} parameter} string unix-sock-dir
32151 The directory in which sockets will be found/created.
32153 Defaults to @samp{"/var/run/libvirt"}.
32157 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-ro
32158 Authentication scheme for UNIX read-only sockets. By default socket
32159 permissions allow anyone to connect
32161 Defaults to @samp{"polkit"}.
32165 @deftypevr {@code{libvirt-configuration} parameter} string auth-unix-rw
32166 Authentication scheme for UNIX read-write sockets. By default socket
32167 permissions only allow root. If PolicyKit support was compiled into
32168 libvirt, the default will be to use 'polkit' auth.
32170 Defaults to @samp{"polkit"}.
32174 @deftypevr {@code{libvirt-configuration} parameter} string auth-tcp
32175 Authentication scheme for TCP sockets. If you don't enable SASL, then
32176 all TCP traffic is cleartext. Don't do this outside of a dev/test
32179 Defaults to @samp{"sasl"}.
32183 @deftypevr {@code{libvirt-configuration} parameter} string auth-tls
32184 Authentication scheme for TLS sockets. TLS sockets already have
32185 encryption provided by the TLS layer, and limited authentication is done
32188 It is possible to make use of any SASL authentication mechanism as well,
32189 by using 'sasl' for this option
32191 Defaults to @samp{"none"}.
32195 @deftypevr {@code{libvirt-configuration} parameter} optional-list access-drivers
32196 API access control scheme.
32198 By default an authenticated user is allowed access to all APIs. Access
32199 drivers can place restrictions on this.
32201 Defaults to @samp{()}.
32205 @deftypevr {@code{libvirt-configuration} parameter} string key-file
32206 Server key file path. If set to an empty string, then no private key is
32209 Defaults to @samp{""}.
32213 @deftypevr {@code{libvirt-configuration} parameter} string cert-file
32214 Server key file path. If set to an empty string, then no certificate is
32217 Defaults to @samp{""}.
32221 @deftypevr {@code{libvirt-configuration} parameter} string ca-file
32222 Server key file path. If set to an empty string, then no CA certificate
32225 Defaults to @samp{""}.
32229 @deftypevr {@code{libvirt-configuration} parameter} string crl-file
32230 Certificate revocation list path. If set to an empty string, then no
32233 Defaults to @samp{""}.
32237 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-sanity-cert
32238 Disable verification of our own server certificates.
32240 When libvirtd starts it performs some sanity checks against its own
32243 Defaults to @samp{#f}.
32247 @deftypevr {@code{libvirt-configuration} parameter} boolean tls-no-verify-cert
32248 Disable verification of client certificates.
32250 Client certificate verification is the primary authentication mechanism.
32251 Any client which does not present a certificate signed by the CA will be
32254 Defaults to @samp{#f}.
32258 @deftypevr {@code{libvirt-configuration} parameter} optional-list tls-allowed-dn-list
32259 Whitelist of allowed x509 Distinguished Name.
32261 Defaults to @samp{()}.
32265 @deftypevr {@code{libvirt-configuration} parameter} optional-list sasl-allowed-usernames
32266 Whitelist of allowed SASL usernames. The format for username depends on
32267 the SASL authentication mechanism.
32269 Defaults to @samp{()}.
32273 @deftypevr {@code{libvirt-configuration} parameter} string tls-priority
32274 Override the compile time default TLS priority string. The default is
32275 usually @samp{"NORMAL"} unless overridden at build time. Only set this is it
32276 is desired for libvirt to deviate from the global default settings.
32278 Defaults to @samp{"NORMAL"}.
32282 @deftypevr {@code{libvirt-configuration} parameter} integer max-clients
32283 Maximum number of concurrent client connections to allow over all
32286 Defaults to @samp{5000}.
32290 @deftypevr {@code{libvirt-configuration} parameter} integer max-queued-clients
32291 Maximum length of queue of connections waiting to be accepted by the
32292 daemon. Note, that some protocols supporting retransmission may obey
32293 this so that a later reattempt at connection succeeds.
32295 Defaults to @samp{1000}.
32299 @deftypevr {@code{libvirt-configuration} parameter} integer max-anonymous-clients
32300 Maximum length of queue of accepted but not yet authenticated clients.
32301 Set this to zero to turn this feature off
32303 Defaults to @samp{20}.
32307 @deftypevr {@code{libvirt-configuration} parameter} integer min-workers
32308 Number of workers to start up initially.
32310 Defaults to @samp{5}.
32314 @deftypevr {@code{libvirt-configuration} parameter} integer max-workers
32315 Maximum number of worker threads.
32317 If the number of active clients exceeds @code{min-workers}, then more
32318 threads are spawned, up to max_workers limit. Typically you'd want
32319 max_workers to equal maximum number of clients allowed.
32321 Defaults to @samp{20}.
32325 @deftypevr {@code{libvirt-configuration} parameter} integer prio-workers
32326 Number of priority workers. If all workers from above pool are stuck,
32327 some calls marked as high priority (notably domainDestroy) can be
32328 executed in this pool.
32330 Defaults to @samp{5}.
32334 @deftypevr {@code{libvirt-configuration} parameter} integer max-requests
32335 Total global limit on concurrent RPC calls.
32337 Defaults to @samp{20}.
32341 @deftypevr {@code{libvirt-configuration} parameter} integer max-client-requests
32342 Limit on concurrent requests from a single client connection. To avoid
32343 one client monopolizing the server this should be a small fraction of
32344 the global max_requests and max_workers parameter.
32346 Defaults to @samp{5}.
32350 @deftypevr {@code{libvirt-configuration} parameter} integer admin-min-workers
32351 Same as @code{min-workers} but for the admin interface.
32353 Defaults to @samp{1}.
32357 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-workers
32358 Same as @code{max-workers} but for the admin interface.
32360 Defaults to @samp{5}.
32364 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-clients
32365 Same as @code{max-clients} but for the admin interface.
32367 Defaults to @samp{5}.
32371 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-queued-clients
32372 Same as @code{max-queued-clients} but for the admin interface.
32374 Defaults to @samp{5}.
32378 @deftypevr {@code{libvirt-configuration} parameter} integer admin-max-client-requests
32379 Same as @code{max-client-requests} but for the admin interface.
32381 Defaults to @samp{5}.
32385 @deftypevr {@code{libvirt-configuration} parameter} integer log-level
32386 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
32388 Defaults to @samp{3}.
32392 @deftypevr {@code{libvirt-configuration} parameter} string log-filters
32395 A filter allows to select a different logging level for a given category
32396 of logs. The format for a filter is one of:
32407 where @code{name} is a string which is matched against the category
32408 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
32409 file, e.g., @samp{"remote"}, @samp{"qemu"}, or @samp{"util.json"} (the
32410 name in the filter can be a substring of the full category name, in
32411 order to match multiple similar categories), the optional @samp{"+"}
32412 prefix tells libvirt to log stack trace for each message matching name,
32413 and @code{x} is the minimal level where matching messages should be
32431 Multiple filters can be defined in a single filters statement, they just
32432 need to be separated by spaces.
32434 Defaults to @samp{"3:remote 4:event"}.
32438 @deftypevr {@code{libvirt-configuration} parameter} string log-outputs
32441 An output is one of the places to save logging information. The format
32442 for an output can be:
32446 output goes to stderr
32448 @item x:syslog:name
32449 use syslog for the output and use the given name as the ident
32451 @item x:file:file_path
32452 output to a file, with the given filepath
32455 output to journald logging system
32459 In all case the x prefix is the minimal level, acting as a filter
32476 Multiple outputs can be defined, they just need to be separated by
32479 Defaults to @samp{"3:stderr"}.
32483 @deftypevr {@code{libvirt-configuration} parameter} integer audit-level
32484 Allows usage of the auditing subsystem to be altered
32488 0: disable all auditing
32491 1: enable auditing, only if enabled on host
32494 2: enable auditing, and exit if disabled on host.
32498 Defaults to @samp{1}.
32502 @deftypevr {@code{libvirt-configuration} parameter} boolean audit-logging
32503 Send audit messages via libvirt logging infrastructure.
32505 Defaults to @samp{#f}.
32509 @deftypevr {@code{libvirt-configuration} parameter} optional-string host-uuid
32510 Host UUID@. UUID must not have all digits be the same.
32512 Defaults to @samp{""}.
32516 @deftypevr {@code{libvirt-configuration} parameter} string host-uuid-source
32517 Source to read host UUID.
32521 @code{smbios}: fetch the UUID from @code{dmidecode -s system-uuid}
32524 @code{machine-id}: fetch the UUID from @code{/etc/machine-id}
32528 If @code{dmidecode} does not provide a valid UUID a temporary UUID will
32531 Defaults to @samp{"smbios"}.
32535 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-interval
32536 A keepalive message is sent to a client after @code{keepalive_interval}
32537 seconds of inactivity to check if the client is still responding. If
32538 set to -1, libvirtd will never send keepalive requests; however clients
32539 can still send them and the daemon will send responses.
32541 Defaults to @samp{5}.
32545 @deftypevr {@code{libvirt-configuration} parameter} integer keepalive-count
32546 Maximum number of keepalive messages that are allowed to be sent to the
32547 client without getting any response before the connection is considered
32550 In other words, the connection is automatically closed approximately
32551 after @code{keepalive_interval * (keepalive_count + 1)} seconds since
32552 the last message received from the client. When @code{keepalive-count}
32553 is set to 0, connections will be automatically closed after
32554 @code{keepalive-interval} seconds of inactivity without sending any
32555 keepalive messages.
32557 Defaults to @samp{5}.
32561 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-interval
32562 Same as above but for admin interface.
32564 Defaults to @samp{5}.
32568 @deftypevr {@code{libvirt-configuration} parameter} integer admin-keepalive-count
32569 Same as above but for admin interface.
32571 Defaults to @samp{5}.
32575 @deftypevr {@code{libvirt-configuration} parameter} integer ovs-timeout
32576 Timeout for Open vSwitch calls.
32578 The @code{ovs-vsctl} utility is used for the configuration and its
32579 timeout option is set by default to 5 seconds to avoid potential
32580 infinite waits blocking libvirt.
32582 Defaults to @samp{5}.
32586 @c %end of autogenerated docs
32588 @subsubheading Virtlog daemon
32589 The virtlogd service is a server side daemon component of libvirt that is
32590 used to manage logs from virtual machine consoles.
32592 This daemon is not used directly by libvirt client applications, rather it
32593 is called on their behalf by @code{libvirtd}. By maintaining the logs in a
32594 standalone daemon, the main @code{libvirtd} daemon can be restarted without
32595 risk of losing logs. The @code{virtlogd} daemon has the ability to re-exec()
32596 itself upon receiving @code{SIGUSR1}, to allow live upgrades without downtime.
32598 @deffn {Scheme Variable} virtlog-service-type
32599 This is the type of the virtlog daemon.
32600 Its value must be a @code{virtlog-configuration}.
32603 (service virtlog-service-type
32604 (virtlog-configuration
32605 (max-clients 1000)))
32609 @deftypevar {@code{libvirt} parameter} package libvirt
32613 @deftypevr {@code{virtlog-configuration} parameter} integer log-level
32614 Logging level. 4 errors, 3 warnings, 2 information, 1 debug.
32616 Defaults to @samp{3}.
32620 @deftypevr {@code{virtlog-configuration} parameter} string log-filters
32623 A filter allows to select a different logging level for a given category
32624 of logs The format for a filter is one of:
32635 where @code{name} is a string which is matched against the category
32636 given in the @code{VIR_LOG_INIT()} at the top of each libvirt source
32637 file, e.g., "remote", "qemu", or "util.json" (the name in the filter can
32638 be a substring of the full category name, in order to match multiple
32639 similar categories), the optional "+" prefix tells libvirt to log stack
32640 trace for each message matching name, and @code{x} is the minimal level
32641 where matching messages should be logged:
32658 Multiple filters can be defined in a single filters statement, they just
32659 need to be separated by spaces.
32661 Defaults to @samp{"3:remote 4:event"}.
32665 @deftypevr {@code{virtlog-configuration} parameter} string log-outputs
32668 An output is one of the places to save logging information The format
32669 for an output can be:
32673 output goes to stderr
32675 @item x:syslog:name
32676 use syslog for the output and use the given name as the ident
32678 @item x:file:file_path
32679 output to a file, with the given filepath
32682 output to journald logging system
32686 In all case the x prefix is the minimal level, acting as a filter
32703 Multiple outputs can be defined, they just need to be separated by
32706 Defaults to @samp{"3:stderr"}.
32710 @deftypevr {@code{virtlog-configuration} parameter} integer max-clients
32711 Maximum number of concurrent client connections to allow over all
32714 Defaults to @samp{1024}.
32718 @deftypevr {@code{virtlog-configuration} parameter} integer max-size
32719 Maximum file size before rolling over.
32721 Defaults to @samp{2MB}
32725 @deftypevr {@code{virtlog-configuration} parameter} integer max-backups
32726 Maximum number of backup files to keep.
32728 Defaults to @samp{3}
32732 @anchor{transparent-emulation-qemu}
32733 @subsubheading Transparent Emulation with QEMU
32736 @cindex @code{binfmt_misc}
32737 @code{qemu-binfmt-service-type} provides support for transparent
32738 emulation of program binaries built for different architectures---e.g.,
32739 it allows you to transparently execute an ARMv7 program on an x86_64
32740 machine. It achieves this by combining the @uref{https://www.qemu.org,
32741 QEMU} emulator and the @code{binfmt_misc} feature of the kernel Linux.
32742 This feature only allows you to emulate GNU/Linux on a different
32743 architecture, but see below for GNU/Hurd support.
32745 @defvr {Scheme Variable} qemu-binfmt-service-type
32746 This is the type of the QEMU/binfmt service for transparent emulation.
32747 Its value must be a @code{qemu-binfmt-configuration} object, which
32748 specifies the QEMU package to use as well as the architecture we want to
32752 (service qemu-binfmt-service-type
32753 (qemu-binfmt-configuration
32754 (platforms (lookup-qemu-platforms "arm" "aarch64"))))
32757 In this example, we enable transparent emulation for the ARM and aarch64
32758 platforms. Running @code{herd stop qemu-binfmt} turns it off, and
32759 running @code{herd start qemu-binfmt} turns it back on (@pxref{Invoking
32760 herd, the @command{herd} command,, shepherd, The GNU Shepherd Manual}).
32763 @deftp {Data Type} qemu-binfmt-configuration
32764 This is the configuration for the @code{qemu-binfmt} service.
32767 @item @code{platforms} (default: @code{'()})
32768 The list of emulated QEMU platforms. Each item must be a @dfn{platform
32769 object} as returned by @code{lookup-qemu-platforms} (see below).
32771 For example, let's suppose you're on an x86_64 machine and you have this
32775 (service qemu-binfmt-service-type
32776 (qemu-binfmt-configuration
32777 (platforms (lookup-qemu-platforms "arm"))))
32783 guix build -s armhf-linux inkscape
32787 and it will build Inkscape for ARMv7 @emph{as if it were a native
32788 build}, transparently using QEMU to emulate the ARMv7 CPU@. Pretty handy
32789 if you'd like to test a package build for an architecture you don't have
32792 @item @code{qemu} (default: @code{qemu})
32793 The QEMU package to use.
32797 @deffn {Scheme Procedure} lookup-qemu-platforms @var{platforms}@dots{}
32798 Return the list of QEMU platform objects corresponding to
32799 @var{platforms}@dots{}. @var{platforms} must be a list of strings
32800 corresponding to platform names, such as @code{"arm"}, @code{"sparc"},
32801 @code{"mips64el"}, and so on.
32804 @deffn {Scheme Procedure} qemu-platform? @var{obj}
32805 Return true if @var{obj} is a platform object.
32808 @deffn {Scheme Procedure} qemu-platform-name @var{platform}
32809 Return the name of @var{platform}---a string such as @code{"arm"}.
32813 @subsubheading QEMU Guest Agent
32817 The QEMU guest agent provides control over the emulated system to the
32818 host. The @code{qemu-guest-agent} service runs the agent on Guix
32819 guests. To control the agent from the host, open a socket by invoking
32820 QEMU with the following arguments:
32823 qemu-system-x86_64 \
32824 -chardev socket,path=/tmp/qga.sock,server=on,wait=off,id=qga0 \
32825 -device virtio-serial \
32826 -device virtserialport,chardev=qga0,name=org.qemu.guest_agent.0 \
32830 This creates a socket at @file{/tmp/qga.sock} on the host. Once the
32831 guest agent is running, you can issue commands with @code{socat}:
32834 $ guix shell socat -- socat unix-connect:/tmp/qga.sock stdio
32835 @{"execute": "guest-get-host-name"@}
32836 @{"return": @{"host-name": "guix"@}@}
32839 See @url{https://wiki.qemu.org/Features/GuestAgent,QEMU guest agent
32840 documentation} for more options and commands.
32842 @defvr {Scheme Variable} qemu-guest-agent-service-type
32843 Service type for the QEMU guest agent service.
32846 @deftp {Data Type} qemu-guest-agent-configuration
32847 Configuration for the @code{qemu-guest-agent} service.
32850 @item @code{qemu} (default: @code{qemu-minimal})
32851 The QEMU package to use.
32853 @item @code{device} (default: @code{""})
32854 File name of the device or socket the agent uses to communicate with the
32855 host. If empty, QEMU uses a default file name.
32860 @subsubheading The Hurd in a Virtual Machine
32862 @cindex @code{hurd}
32866 Service @code{hurd-vm} provides support for running GNU/Hurd in a
32867 virtual machine (VM), a so-called @dfn{childhurd}. This service is meant
32868 to be used on GNU/Linux and the given GNU/Hurd operating system
32869 configuration is cross-compiled. The virtual machine is a Shepherd
32870 service that can be referred to by the names @code{hurd-vm} and
32871 @code{childhurd} and be controlled with commands such as:
32875 herd stop childhurd
32878 When the service is running, you can view its console by connecting to
32879 it with a VNC client, for example with:
32882 guix shell tigervnc-client -- vncviewer localhost:5900
32885 The default configuration (see @code{hurd-vm-configuration} below)
32886 spawns a secure shell (SSH) server in your GNU/Hurd system, which QEMU
32887 (the virtual machine emulator) redirects to port 10222 on the host.
32888 Thus, you can connect over SSH to the childhurd with:
32891 ssh root@@localhost -p 10022
32894 The childhurd is volatile and stateless: it starts with a fresh root
32895 file system every time you restart it. By default though, all the files
32896 under @file{/etc/childhurd} on the host are copied as is to the root
32897 file system of the childhurd when it boots. This allows you to
32898 initialize ``secrets'' inside the VM: SSH host keys, authorized
32899 substitute keys, and so on---see the explanation of @code{secret-root}
32902 @defvr {Scheme Variable} hurd-vm-service-type
32903 This is the type of the Hurd in a Virtual Machine service. Its value
32904 must be a @code{hurd-vm-configuration} object, which specifies the
32905 operating system (@pxref{operating-system Reference}) and the disk size
32906 for the Hurd Virtual Machine, the QEMU package to use as well as the
32907 options for running it.
32912 (service hurd-vm-service-type
32913 (hurd-vm-configuration
32914 (disk-size (* 5000 (expt 2 20))) ;5G
32915 (memory-size 1024))) ;1024MiB
32918 would create a disk image big enough to build GNU@tie{}Hello, with some
32922 @deftp {Data Type} hurd-vm-configuration
32923 The data type representing the configuration for
32924 @code{hurd-vm-service-type}.
32927 @item @code{os} (default: @var{%hurd-vm-operating-system})
32928 The operating system to instantiate. This default is bare-bones with a
32929 permissive OpenSSH secure shell daemon listening on port 2222
32930 (@pxref{Networking Services, @code{openssh-service-type}}).
32932 @item @code{qemu} (default: @code{qemu-minimal})
32933 The QEMU package to use.
32935 @item @code{image} (default: @var{hurd-vm-disk-image})
32936 The procedure used to build the disk-image built from this
32939 @item @code{disk-size} (default: @code{'guess})
32940 The size of the disk image.
32942 @item @code{memory-size} (default: @code{512})
32943 The memory size of the Virtual Machine in mebibytes.
32945 @item @code{options} (default: @code{'("--snapshot")})
32946 The extra options for running QEMU.
32948 @item @code{id} (default: @code{#f})
32949 If set, a non-zero positive integer used to parameterize Childhurd
32950 instances. It is appended to the service's name,
32951 e.g. @code{childhurd1}.
32953 @item @code{net-options} (default: @var{hurd-vm-net-options})
32954 The procedure used to produce the list of QEMU networking options.
32956 By default, it produces
32959 '("--device" "rtl8139,netdev=net0"
32960 "--netdev" (string-append
32962 "hostfwd=tcp:127.0.0.1:@var{secrets-port}-:1004,"
32963 "hostfwd=tcp:127.0.0.1:@var{ssh-port}-:2222,"
32964 "hostfwd=tcp:127.0.0.1:@var{vnc-port}-:5900"))
32967 with forwarded ports:
32970 @var{secrets-port}: @code{(+ 11004 (* 1000 @var{ID}))}
32971 @var{ssh-port}: @code{(+ 10022 (* 1000 @var{ID}))}
32972 @var{vnc-port}: @code{(+ 15900 (* 1000 @var{ID}))}
32975 @item @code{secret-root} (default: @file{/etc/childhurd})
32976 The root directory with out-of-band secrets to be installed into the
32977 childhurd once it runs. Childhurds are volatile which means that on
32978 every startup, secrets such as the SSH host keys and Guix signing key
32981 If the @file{/etc/childhurd} directory does not exist, the
32982 @code{secret-service} running in the Childhurd will be sent an empty
32985 By default, the service automatically populates @file{/etc/childhurd}
32986 with the following non-volatile secrets, unless they already exist:
32989 /etc/childhurd/etc/guix/acl
32990 /etc/childhurd/etc/guix/signing-key.pub
32991 /etc/childhurd/etc/guix/signing-key.sec
32992 /etc/childhurd/etc/ssh/ssh_host_ed25519_key
32993 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key
32994 /etc/childhurd/etc/ssh/ssh_host_ed25519_key.pub
32995 /etc/childhurd/etc/ssh/ssh_host_ecdsa_key.pub
32998 These files are automatically sent to the guest Hurd VM when it boots,
32999 including permissions.
33001 @cindex childhurd, offloading
33002 @cindex Hurd, offloading
33003 Having these files in place means that only a couple of things are
33004 missing to allow the host to offload @code{i586-gnu} builds to the
33009 Authorizing the childhurd's key on the host so that the host accepts
33010 build results coming from the childhurd, which can be done like so:
33013 guix archive --authorize < \
33014 /etc/childhurd/etc/guix/signing-key.pub
33018 Adding the childhurd to @file{/etc/guix/machines.scm} (@pxref{Daemon
33022 We're working towards making that happen automatically---get in touch
33023 with us at @email{guix-devel@@gnu.org} to discuss it!
33027 Note that by default the VM image is volatile, i.e., once stopped the
33028 contents are lost. If you want a stateful image instead, override the
33029 configuration's @code{image} and @code{options} without
33030 the @code{--snapshot} flag using something along these lines:
33033 (service hurd-vm-service-type
33034 (hurd-vm-configuration
33035 (image (const "/out/of/store/writable/hurd.img"))
33039 @subsubheading Ganeti
33044 This service is considered experimental. Configuration options may be changed
33045 in a backwards-incompatible manner, and not all features have been thorougly
33046 tested. Users of this service are encouraged to share their experience at
33047 @email{guix-devel@@gnu.org}.
33050 Ganeti is a virtual machine management system. It is designed to keep virtual
33051 machines running on a cluster of servers even in the event of hardware failures,
33052 and to make maintenance and recovery tasks easy. It consists of multiple
33053 services which are described later in this section. In addition to the Ganeti
33054 service, you will need the OpenSSH service (@pxref{Networking Services,
33055 @code{openssh-service-type}}), and update the @file{/etc/hosts} file
33056 (@pxref{operating-system Reference, @code{hosts-file}}) with the cluster name
33057 and address (or use a DNS server).
33059 All nodes participating in a Ganeti cluster should have the same Ganeti and
33060 @file{/etc/hosts} configuration. Here is an example configuration for a Ganeti
33061 cluster node that supports multiple storage backends, and installs the
33062 @code{debootstrap} and @code{guix} @dfn{OS providers}:
33065 (use-package-modules virtualization)
33066 (use-service-modules base ganeti networking ssh)
33069 (host-name "node1")
33070 (hosts-file (plain-file "hosts" (format #f "
33071 127.0.0.1 localhost
33074 192.168.1.200 ganeti.example.com
33075 192.168.1.201 node1.example.com node1
33076 192.168.1.202 node2.example.com node2
33079 ;; Install QEMU so we can use KVM-based instances, and LVM, DRBD and Ceph
33080 ;; in order to use the "plain", "drbd" and "rbd" storage backends.
33081 (packages (append (map specification->package
33082 '("qemu" "lvm2" "drbd-utils" "ceph"
33083 ;; Add the debootstrap and guix OS providers.
33084 "ganeti-instance-guix" "ganeti-instance-debootstrap"))
33087 (append (list (service static-networking-service-type
33088 (list (static-networking
33090 (list (network-address
33092 (value "192.168.1.201/24"))))
33094 (list (network-route
33095 (destination "default")
33096 (gateway "192.168.1.254"))))
33097 (name-servers '("192.168.1.252"
33098 "192.168.1.253")))))
33100 ;; Ganeti uses SSH to communicate between nodes.
33101 (service openssh-service-type
33102 (openssh-configuration
33103 (permit-root-login 'prohibit-password)))
33105 (service ganeti-service-type
33106 (ganeti-configuration
33107 ;; This list specifies allowed file system paths
33108 ;; for storing virtual machine images.
33109 (file-storage-paths '("/srv/ganeti/file-storage"))
33110 ;; This variable configures a single "variant" for
33111 ;; both Debootstrap and Guix that works with KVM.
33112 (os %default-ganeti-os))))
33116 Users are advised to read the
33117 @url{http://docs.ganeti.org/ganeti/master/html/admin.html,Ganeti
33118 administrators guide} to learn about the various cluster options and
33119 day-to-day operations. There is also a
33120 @url{https://guix.gnu.org/blog/2020/running-a-ganeti-cluster-on-guix/,blog post}
33121 describing how to configure and initialize a small cluster.
33123 @defvr {Scheme Variable} ganeti-service-type
33124 This is a service type that includes all the various services that Ganeti
33127 Its value is a @code{ganeti-configuration} object that defines the package
33128 to use for CLI operations, as well as configuration for the various daemons.
33129 Allowed file storage paths and available guest operating systems are also
33130 configured through this data type.
33133 @deftp {Data Type} ganeti-configuration
33134 The @code{ganeti} service takes the following configuration options:
33137 @item @code{ganeti} (default: @code{ganeti})
33138 The @code{ganeti} package to use. It will be installed to the system profile
33139 and make @command{gnt-cluster}, @command{gnt-instance}, etc available. Note
33140 that the value specified here does not affect the other services as each refer
33141 to a specific @code{ganeti} package (see below).
33143 @item @code{noded-configuration} (default: @code{(ganeti-noded-configuration)})
33144 @itemx @code{confd-configuration} (default: @code{(ganeti-confd-configuration)})
33145 @itemx @code{wconfd-configuration} (default: @code{(ganeti-wconfd-configuration)})
33146 @itemx @code{luxid-configuration} (default: @code{(ganeti-luxid-configuration)})
33147 @itemx @code{rapi-configuration} (default: @code{(ganeti-rapi-configuration)})
33148 @itemx @code{kvmd-configuration} (default: @code{(ganeti-kvmd-configuration)})
33149 @itemx @code{mond-configuration} (default: @code{(ganeti-mond-configuration)})
33150 @itemx @code{metad-configuration} (default: @code{(ganeti-metad-configuration)})
33151 @itemx @code{watcher-configuration} (default: @code{(ganeti-watcher-configuration)})
33152 @itemx @code{cleaner-configuration} (default: @code{(ganeti-cleaner-configuration)})
33154 These options control the various daemons and cron jobs that are distributed
33155 with Ganeti. The possible values for these are described in detail below.
33156 To override a setting, you must use the configuration type for that service:
33159 (service ganeti-service-type
33160 (ganeti-configuration
33161 (rapi-configuration
33162 (ganeti-rapi-configuration
33163 (interface "eth1"))))
33164 (watcher-configuration
33165 (ganeti-watcher-configuration
33166 (rapi-ip "10.0.0.1"))))
33169 @item @code{file-storage-paths} (default: @code{'()})
33170 List of allowed directories for file storage backend.
33172 @item @code{os} (default: @code{%default-ganeti-os})
33173 List of @code{<ganeti-os>} records.
33176 In essence @code{ganeti-service-type} is shorthand for declaring each service
33180 (service ganeti-noded-service-type)
33181 (service ganeti-confd-service-type)
33182 (service ganeti-wconfd-service-type)
33183 (service ganeti-luxid-service-type)
33184 (service ganeti-kvmd-service-type)
33185 (service ganeti-mond-service-type)
33186 (service ganeti-metad-service-type)
33187 (service ganeti-watcher-service-type)
33188 (service ganeti-cleaner-service-type)
33191 Plus a service extension for @code{etc-service-type} that configures the file
33192 storage backend and OS variants.
33196 @deftp {Data Type} ganeti-os
33197 This data type is suitable for passing to the @code{os} parameter of
33198 @code{ganeti-configuration}. It takes the following parameters:
33202 The name for this OS provider. It is only used to specify where the
33203 configuration ends up. Setting it to ``debootstrap'' will create
33204 @file{/etc/ganeti/instance-debootstrap}.
33206 @item @code{extension}
33207 The file extension for variants of this OS type. For example
33208 @file{.conf} or @file{.scm}.
33210 @item @code{variants} (default: @code{'()})
33211 List of @code{ganeti-os-variant} objects for this OS.
33216 @deftp {Data Type} ganeti-os-variant
33217 This is the data type for a Ganeti OS variant. It takes the following
33222 The name of this variant.
33224 @item @code{configuration}
33225 A configuration file for this variant.
33229 @defvr {Scheme Variable} %default-debootstrap-hooks
33230 This variable contains hooks to configure networking and the GRUB bootloader.
33233 @defvr {Scheme Variable} %default-debootstrap-extra-pkgs
33234 This variable contains a list of packages suitable for a fully-virtualized guest.
33237 @deftp {Data Type} debootstrap-configuration
33239 This data type creates configuration files suitable for the debootstrap OS provider.
33242 @item @code{hooks} (default: @code{%default-debootstrap-hooks})
33243 When not @code{#f}, this must be a G-expression that specifies a directory with
33244 scripts that will run when the OS is installed. It can also be a list of
33245 @code{(name . file-like)} pairs. For example:
33248 `((99-hello-world . ,(plain-file "#!/bin/sh\necho Hello, World")))
33251 That will create a directory with one executable named @code{99-hello-world}
33252 and run it every time this variant is installed. If set to @code{#f}, hooks
33253 in @file{/etc/ganeti/instance-debootstrap/hooks} will be used, if any.
33254 @item @code{proxy} (default: @code{#f})
33255 Optional HTTP proxy to use.
33256 @item @code{mirror} (default: @code{#f})
33257 The Debian mirror. Typically something like @code{http://ftp.no.debian.org/debian}.
33258 The default varies depending on the distribution.
33259 @item @code{arch} (default: @code{#f})
33260 The dpkg architecture. Set to @code{armhf} to debootstrap an ARMv7 instance
33261 on an AArch64 host. Default is to use the current system architecture.
33262 @item @code{suite} (default: @code{"stable"})
33263 When set, this must be a Debian distribution ``suite'' such as @code{buster}
33264 or @code{focal}. If set to @code{#f}, the default for the OS provider is used.
33265 @item @code{extra-pkgs} (default: @code{%default-debootstrap-extra-pkgs})
33266 List of extra packages that will get installed by dpkg in addition
33267 to the minimal system.
33268 @item @code{components} (default: @code{#f})
33269 When set, must be a list of Debian repository ``components''. For example
33270 @code{'("main" "contrib")}.
33271 @item @code{generate-cache?} (default: @code{#t})
33272 Whether to automatically cache the generated debootstrap archive.
33273 @item @code{clean-cache} (default: @code{14})
33274 Discard the cache after this amount of days. Use @code{#f} to never
33276 @item @code{partition-style} (default: @code{'msdos})
33277 The type of partition to create. When set, it must be one of
33278 @code{'msdos}, @code{'none} or a string.
33279 @item @code{partition-alignment} (default: @code{2048})
33280 Alignment of the partition in sectors.
33284 @deffn {Scheme Procedure} debootstrap-variant @var{name} @var{configuration}
33285 This is a helper procedure that creates a @code{ganeti-os-variant} record. It
33286 takes two parameters: a name and a @code{debootstrap-configuration} object.
33289 @deffn {Scheme Procedure} debootstrap-os @var{variants}@dots{}
33290 This is a helper procedure that creates a @code{ganeti-os} record. It takes
33291 a list of variants created with @code{debootstrap-variant}.
33294 @deffn {Scheme Procedure} guix-variant @var{name} @var{configuration}
33295 This is a helper procedure that creates a @code{ganeti-os-variant} record for
33296 use with the Guix OS provider. It takes a name and a G-expression that returns
33297 a ``file-like'' (@pxref{G-Expressions, file-like objects}) object containing a
33298 Guix System configuration.
33301 @deffn {Scheme Procedure} guix-os @var{variants}@dots{}
33302 This is a helper procedure that creates a @code{ganeti-os} record. It
33303 takes a list of variants produced by @code{guix-variant}.
33306 @defvr {Scheme Variable} %default-debootstrap-variants
33307 This is a convenience variable to make the debootstrap provider work
33308 ``out of the box'' without users having to declare variants manually. It
33309 contains a single debootstrap variant with the default configuration:
33312 (list (debootstrap-variant
33314 (debootstrap-configuration)))
33318 @defvr {Scheme Variable} %default-guix-variants
33319 This is a convenience variable to make the Guix OS provider work without
33320 additional configuration. It creates a virtual machine that has an SSH
33321 server, a serial console, and authorizes the Ganeti hosts SSH keys.
33324 (list (guix-variant
33326 (file-append ganeti-instance-guix
33327 "/share/doc/ganeti-instance-guix/examples/dynamic.scm")))
33331 Users can implement support for OS providers unbeknownst to Guix by extending
33332 the @code{ganeti-os} and @code{ganeti-os-variant} records appropriately.
33338 (extension ".conf")
33340 (list (ganeti-os-variant
33342 (configuration (plain-file "bar" "this is fine"))))))
33345 That creates @file{/etc/ganeti/instance-custom/variants/foo.conf} which points
33346 to a file in the store with contents @code{this is fine}. It also creates
33347 @file{/etc/ganeti/instance-custom/variants/variants.list} with contents @code{foo}.
33349 Obviously this may not work for all OS providers out there. If you find the
33350 interface limiting, please reach out to @email{guix-devel@@gnu.org}.
33352 The rest of this section documents the various services that are included by
33353 @code{ganeti-service-type}.
33355 @defvr {Scheme Variable} ganeti-noded-service-type
33356 @command{ganeti-noded} is the daemon responsible for node-specific functions
33357 within the Ganeti system. The value of this service must be a
33358 @code{ganeti-noded-configuration} object.
33361 @deftp {Data Type} ganeti-noded-configuration
33362 This is the configuration for the @code{ganeti-noded} service.
33365 @item @code{ganeti} (default: @code{ganeti})
33366 The @code{ganeti} package to use for this service.
33368 @item @code{port} (default: @code{1811})
33369 The TCP port on which the node daemon listens for network requests.
33371 @item @code{address} (default: @code{"0.0.0.0"})
33372 The network address that the daemon will bind to. The default address means
33373 bind to all available addresses.
33375 @item @code{interface} (default: @code{#f})
33376 When this is set, it must be a specific network interface (e.g.@: @code{eth0})
33377 that the daemon will bind to.
33379 @item @code{max-clients} (default: @code{20})
33380 This sets a limit on the maximum number of simultaneous client connections
33381 that the daemon will handle. Connections above this count are accepted, but
33382 no responses will be sent until enough connections have closed.
33384 @item @code{ssl?} (default: @code{#t})
33385 Whether to use SSL/TLS to encrypt network communications. The certificate
33386 is automatically provisioned by the cluster and can be rotated with
33387 @command{gnt-cluster renew-crypto}.
33389 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
33390 This can be used to provide a specific encryption key for TLS communications.
33392 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
33393 This can be used to provide a specific certificate for TLS communications.
33395 @item @code{debug?} (default: @code{#f})
33396 When true, the daemon performs additional logging for debugging purposes.
33397 Note that this will leak encryption details to the log files, use with caution.
33402 @defvr {Scheme Variable} ganeti-confd-service-type
33403 @command{ganeti-confd} answers queries related to the configuration of a
33404 Ganeti cluster. The purpose of this daemon is to have a highly available
33405 and fast way to query cluster configuration values. It is automatically
33406 active on all @dfn{master candidates}. The value of this service must be a
33407 @code{ganeti-confd-configuration} object.
33411 @deftp {Data Type} ganeti-confd-configuration
33412 This is the configuration for the @code{ganeti-confd} service.
33415 @item @code{ganeti} (default: @code{ganeti})
33416 The @code{ganeti} package to use for this service.
33418 @item @code{port} (default: @code{1814})
33419 The UDP port on which to listen for network requests.
33421 @item @code{address} (default: @code{"0.0.0.0"})
33422 Network address that the daemon will bind to.
33424 @item @code{debug?} (default: @code{#f})
33425 When true, the daemon performs additional logging for debugging purposes.
33430 @defvr {Scheme Variable} ganeti-wconfd-service-type
33431 @command{ganeti-wconfd} is the daemon that has authoritative knowledge
33432 about the cluster configuration and is the only entity that can accept
33433 changes to it. All jobs that need to modify the configuration will do so
33434 by sending appropriate requests to this daemon. It only runs on the
33435 @dfn{master node} and will automatically disable itself on other nodes.
33437 The value of this service must be a
33438 @code{ganeti-wconfd-configuration} object.
33441 @deftp {Data Type} ganeti-wconfd-configuration
33442 This is the configuration for the @code{ganeti-wconfd} service.
33445 @item @code{ganeti} (default: @code{ganeti})
33446 The @code{ganeti} package to use for this service.
33448 @item @code{no-voting?} (default: @code{#f})
33449 The daemon will refuse to start if the majority of cluster nodes does not
33450 agree that it is running on the master node. Set to @code{#t} to start
33451 even if a quorum can not be reached (dangerous, use with caution).
33453 @item @code{debug?} (default: @code{#f})
33454 When true, the daemon performs additional logging for debugging purposes.
33459 @defvr {Scheme Variable} ganeti-luxid-service-type
33460 @command{ganeti-luxid} is a daemon used to answer queries related to the
33461 configuration and the current live state of a Ganeti cluster. Additionally,
33462 it is the authoritative daemon for the Ganeti job queue. Jobs can be
33463 submitted via this daemon and it schedules and starts them.
33465 It takes a @code{ganeti-luxid-configuration} object.
33468 @deftp {Data Type} ganeti-luxid-configuration
33469 This is the configuration for the @code{ganeti-luxid} service.
33472 @item @code{ganeti} (default: @code{ganeti})
33473 The @code{ganeti} package to use for this service.
33475 @item @code{no-voting?} (default: @code{#f})
33476 The daemon will refuse to start if it cannot verify that the majority of
33477 cluster nodes believes that it is running on the master node. Set to
33478 @code{#t} to ignore such checks and start anyway (this can be dangerous).
33480 @item @code{debug?} (default: @code{#f})
33481 When true, the daemon performs additional logging for debugging purposes.
33486 @defvr {Scheme Variable} ganeti-rapi-service-type
33487 @command{ganeti-rapi} provides a remote API for Ganeti clusters. It runs on
33488 the master node and can be used to perform cluster actions programmatically
33489 via a JSON-based RPC protocol.
33491 Most query operations are allowed without authentication (unless
33492 @var{require-authentication?} is set), whereas write operations require
33493 explicit authorization via the @file{/var/lib/ganeti/rapi/users} file. See
33494 the @url{http://docs.ganeti.org/ganeti/master/html/rapi.html, Ganeti Remote
33495 API documentation} for more information.
33497 The value of this service must be a @code{ganeti-rapi-configuration} object.
33500 @deftp {Data Type} ganeti-rapi-configuration
33501 This is the configuration for the @code{ganeti-rapi} service.
33504 @item @code{ganeti} (default: @code{ganeti})
33505 The @code{ganeti} package to use for this service.
33507 @item @code{require-authentication?} (default: @code{#f})
33508 Whether to require authentication even for read-only operations.
33510 @item @code{port} (default: @code{5080})
33511 The TCP port on which to listen to API requests.
33513 @item @code{address} (default: @code{"0.0.0.0"})
33514 The network address that the service will bind to. By default it listens
33515 on all configured addresses.
33517 @item @code{interface} (default: @code{#f})
33518 When set, it must specify a specific network interface such as @code{eth0}
33519 that the daemon will bind to.
33521 @item @code{max-clients} (default: @code{20})
33522 The maximum number of simultaneous client requests to handle. Further
33523 connections are allowed, but no responses are sent until enough connections
33526 @item @code{ssl?} (default: @code{#t})
33527 Whether to use SSL/TLS encryption on the RAPI port.
33529 @item @code{ssl-key} (default: @file{"/var/lib/ganeti/server.pem"})
33530 This can be used to provide a specific encryption key for TLS communications.
33532 @item @code{ssl-cert} (default: @file{"/var/lib/ganeti/server.pem"})
33533 This can be used to provide a specific certificate for TLS communications.
33535 @item @code{debug?} (default: @code{#f})
33536 When true, the daemon performs additional logging for debugging purposes.
33537 Note that this will leak encryption details to the log files, use with caution.
33542 @defvr {Scheme Variable} ganeti-kvmd-service-type
33543 @command{ganeti-kvmd} is responsible for determining whether a given KVM
33544 instance was shut down by an administrator or a user. Normally Ganeti will
33545 restart an instance that was not stopped through Ganeti itself. If the
33546 cluster option @code{user_shutdown} is true, this daemon monitors the
33547 @code{QMP} socket provided by QEMU and listens for shutdown events, and
33548 marks the instance as @dfn{USER_down} instead of @dfn{ERROR_down} when
33549 it shuts down gracefully by itself.
33551 It takes a @code{ganeti-kvmd-configuration} object.
33554 @deftp {Data Type} ganeti-kvmd-configuration
33557 @item @code{ganeti} (default: @code{ganeti})
33558 The @code{ganeti} package to use for this service.
33560 @item @code{debug?} (default: @code{#f})
33561 When true, the daemon performs additional logging for debugging purposes.
33566 @defvr {Scheme Variable} ganeti-mond-service-type
33567 @command{ganeti-mond} is an optional daemon that provides Ganeti monitoring
33568 functionality. It is responsible for running data collectors and publish the
33569 collected information through a HTTP interface.
33571 It takes a @code{ganeti-mond-configuration} object.
33574 @deftp {Data Type} ganeti-mond-configuration
33577 @item @code{ganeti} (default: @code{ganeti})
33578 The @code{ganeti} package to use for this service.
33580 @item @code{port} (default: @code{1815})
33581 The port on which the daemon will listen.
33583 @item @code{address} (default: @code{"0.0.0.0"})
33584 The network address that the daemon will bind to. By default it binds to all
33585 available interfaces.
33587 @item @code{debug?} (default: @code{#f})
33588 When true, the daemon performs additional logging for debugging purposes.
33593 @defvr {Scheme Variable} ganeti-metad-service-type
33594 @command{ganeti-metad} is an optional daemon that can be used to provide
33595 information about the cluster to instances or OS install scripts.
33597 It takes a @code{ganeti-metad-configuration} object.
33600 @deftp {Data Type} ganeti-metad-configuration
33603 @item @code{ganeti} (default: @code{ganeti})
33604 The @code{ganeti} package to use for this service.
33606 @item @code{port} (default: @code{80})
33607 The port on which the daemon will listen.
33609 @item @code{address} (default: @code{#f})
33610 If set, the daemon will bind to this address only. If left unset, the behavior
33611 depends on the cluster configuration.
33613 @item @code{debug?} (default: @code{#f})
33614 When true, the daemon performs additional logging for debugging purposes.
33619 @defvr {Scheme Variable} ganeti-watcher-service-type
33620 @command{ganeti-watcher} is a script designed to run periodically and ensure
33621 the health of a cluster. It will automatically restart instances that have
33622 stopped without Ganeti's consent, and repairs DRBD links in case a node has
33623 rebooted. It also archives old cluster jobs and restarts Ganeti daemons
33624 that are not running. If the cluster parameter @code{ensure_node_health}
33625 is set, the watcher will also shutdown instances and DRBD devices if the
33626 node it is running on is declared offline by known master candidates.
33628 It can be paused on all nodes with @command{gnt-cluster watcher pause}.
33630 The service takes a @code{ganeti-watcher-configuration} object.
33633 @deftp {Data Type} ganeti-watcher-configuration
33636 @item @code{ganeti} (default: @code{ganeti})
33637 The @code{ganeti} package to use for this service.
33639 @item @code{schedule} (default: @code{'(next-second-from (next-minute (range 0 60 5)))})
33640 How often to run the script. The default is every five minutes.
33642 @item @code{rapi-ip} (default: @code{#f})
33643 This option needs to be specified only if the RAPI daemon is configured to use
33644 a particular interface or address. By default the cluster address is used.
33646 @item @code{job-age} (default: @code{(* 6 3600)})
33647 Archive cluster jobs older than this age, specified in seconds. The default
33648 is 6 hours. This keeps @command{gnt-job list} manageable.
33650 @item @code{verify-disks?} (default: @code{#t})
33651 If this is @code{#f}, the watcher will not try to repair broken DRBD links
33652 automatically. Administrators will need to use @command{gnt-cluster verify-disks}
33655 @item @code{debug?} (default: @code{#f})
33656 When @code{#t}, the script performs additional logging for debugging purposes.
33661 @defvr {Scheme Variable} ganeti-cleaner-service-type
33662 @command{ganeti-cleaner} is a script designed to run periodically and remove
33663 old files from the cluster. This service type controls two @dfn{cron jobs}:
33664 one intended for the master node that permanently purges old cluster jobs,
33665 and one intended for every node that removes expired X509 certificates, keys,
33666 and outdated @command{ganeti-watcher} information. Like all Ganeti services,
33667 it is safe to include even on non-master nodes as it will disable itself as
33670 It takes a @code{ganeti-cleaner-configuration} object.
33673 @deftp {Data Type} ganeti-cleaner-configuration
33676 @item @code{ganeti} (default: @code{ganeti})
33677 The @code{ganeti} package to use for the @command{gnt-cleaner} command.
33679 @item @code{master-schedule} (default: @code{"45 1 * * *"})
33680 How often to run the master cleaning job. The default is once per day, at
33683 @item @code{node-schedule} (default: @code{"45 2 * * *"})
33684 How often to run the node cleaning job. The default is once per day, at
33690 @node Version Control Services
33691 @subsection Version Control Services
33693 The @code{(gnu services version-control)} module provides a service to
33694 allow remote access to local Git repositories. There are three options:
33695 the @code{git-daemon-service}, which provides access to repositories via
33696 the @code{git://} unsecured TCP-based protocol, extending the
33697 @code{nginx} web server to proxy some requests to
33698 @code{git-http-backend}, or providing a web interface with
33699 @code{cgit-service-type}.
33701 @deffn {Scheme Procedure} git-daemon-service [#:config (git-daemon-configuration)]
33703 Return a service that runs @command{git daemon}, a simple TCP server to
33704 expose repositories over the Git protocol for anonymous access.
33706 The optional @var{config} argument should be a
33707 @code{<git-daemon-configuration>} object, by default it allows read-only
33708 access to exported@footnote{By creating the magic file
33709 @file{git-daemon-export-ok} in the repository directory.} repositories under
33714 @deftp {Data Type} git-daemon-configuration
33715 Data type representing the configuration for @code{git-daemon-service}.
33718 @item @code{package} (default: @code{git})
33719 Package object of the Git distributed version control system.
33721 @item @code{export-all?} (default: @code{#f})
33722 Whether to allow access for all Git repositories, even if they do not
33723 have the @file{git-daemon-export-ok} file.
33725 @item @code{base-path} (default: @file{/srv/git})
33726 Whether to remap all the path requests as relative to the given path.
33727 If you run @command{git daemon} with @code{(base-path "/srv/git")} on
33728 @samp{example.com}, then if you later try to pull
33729 @indicateurl{git://example.com/hello.git}, git daemon will interpret the
33730 path as @file{/srv/git/hello.git}.
33732 @item @code{user-path} (default: @code{#f})
33733 Whether to allow @code{~user} notation to be used in requests. When
33734 specified with empty string, requests to
33735 @indicateurl{git://host/~alice/foo} is taken as a request to access
33736 @code{foo} repository in the home directory of user @code{alice}. If
33737 @code{(user-path "@var{path}")} is specified, the same request is taken
33738 as a request to access @file{@var{path}/foo} repository in the home
33739 directory of user @code{alice}.
33741 @item @code{listen} (default: @code{'()})
33742 Whether to listen on specific IP addresses or hostnames, defaults to
33745 @item @code{port} (default: @code{#f})
33746 Whether to listen on an alternative port, which defaults to 9418.
33748 @item @code{whitelist} (default: @code{'()})
33749 If not empty, only allow access to this list of directories.
33751 @item @code{extra-options} (default: @code{'()})
33752 Extra options will be passed to @command{git daemon}, please run
33753 @command{man git-daemon} for more information.
33758 The @code{git://} protocol lacks authentication. When you pull from a
33759 repository fetched via @code{git://}, you don't know whether the data you
33760 receive was modified or is even coming from the specified host, and your
33761 connection is subject to eavesdropping. It's better to use an authenticated
33762 and encrypted transport, such as @code{https}. Although Git allows you
33763 to serve repositories using unsophisticated file-based web servers,
33764 there is a faster protocol implemented by the @code{git-http-backend}
33765 program. This program is the back-end of a proper Git web service. It
33766 is designed to sit behind a FastCGI proxy. @xref{Web Services}, for more
33767 on running the necessary @code{fcgiwrap} daemon.
33769 Guix has a separate configuration data type for serving Git repositories
33772 @deftp {Data Type} git-http-configuration
33773 Data type representing the configuration for a future
33774 @code{git-http-service-type}; can currently be used to configure Nginx
33775 through @code{git-http-nginx-location-configuration}.
33778 @item @code{package} (default: @var{git})
33779 Package object of the Git distributed version control system.
33781 @item @code{git-root} (default: @file{/srv/git})
33782 Directory containing the Git repositories to expose to the world.
33784 @item @code{export-all?} (default: @code{#f})
33785 Whether to expose access for all Git repositories in @var{git-root},
33786 even if they do not have the @file{git-daemon-export-ok} file.
33788 @item @code{uri-path} (default: @samp{/git/})
33789 Path prefix for Git access. With the default @samp{/git/} prefix, this
33790 will map @indicateurl{http://@var{server}/git/@var{repo}.git} to
33791 @file{/srv/git/@var{repo}.git}. Requests whose URI paths do not begin
33792 with this prefix are not passed on to this Git instance.
33794 @item @code{fcgiwrap-socket} (default: @code{127.0.0.1:9000})
33795 The socket on which the @code{fcgiwrap} daemon is listening. @xref{Web
33800 There is no @code{git-http-service-type}, currently; instead you can
33801 create an @code{nginx-location-configuration} from a
33802 @code{git-http-configuration} and then add that location to a web
33805 @deffn {Scheme Procedure} git-http-nginx-location-configuration @
33806 [config=(git-http-configuration)]
33807 Compute an @code{nginx-location-configuration} that corresponds to the
33808 given Git http configuration. An example nginx service definition to
33809 serve the default @file{/srv/git} over HTTPS might be:
33812 (service nginx-service-type
33813 (nginx-configuration
33816 (nginx-server-configuration
33817 (listen '("443 ssl"))
33818 (server-name "git.my-host.org")
33820 "/etc/letsencrypt/live/git.my-host.org/fullchain.pem")
33821 (ssl-certificate-key
33822 "/etc/letsencrypt/live/git.my-host.org/privkey.pem")
33825 (git-http-nginx-location-configuration
33826 (git-http-configuration (uri-path "/"))))))))))
33829 This example assumes that you are using Let's Encrypt to get your TLS
33830 certificate. @xref{Certificate Services}. The default @code{certbot}
33831 service will redirect all HTTP traffic on @code{git.my-host.org} to
33832 HTTPS@. You will also need to add an @code{fcgiwrap} proxy to your
33833 system services. @xref{Web Services}.
33836 @subsubheading Cgit Service
33838 @cindex Cgit service
33839 @cindex Git, web interface
33840 @uref{https://git.zx2c4.com/cgit/, Cgit} is a web frontend for Git
33841 repositories written in C.
33843 The following example will configure the service with default values.
33844 By default, Cgit can be accessed on port 80 (@code{http://localhost:80}).
33847 (service cgit-service-type)
33850 The @code{file-object} type designates either a file-like object
33851 (@pxref{G-Expressions, file-like objects}) or a string.
33853 @c %start of fragment
33855 Available @code{cgit-configuration} fields are:
33857 @deftypevr {@code{cgit-configuration} parameter} package package
33862 @deftypevr {@code{cgit-configuration} parameter} nginx-server-configuration-list nginx
33863 NGINX configuration.
33867 @deftypevr {@code{cgit-configuration} parameter} file-object about-filter
33868 Specifies a command which will be invoked to format the content of about
33869 pages (both top-level and for each repository).
33871 Defaults to @samp{""}.
33875 @deftypevr {@code{cgit-configuration} parameter} string agefile
33876 Specifies a path, relative to each repository path, which can be used to
33877 specify the date and time of the youngest commit in the repository.
33879 Defaults to @samp{""}.
33883 @deftypevr {@code{cgit-configuration} parameter} file-object auth-filter
33884 Specifies a command that will be invoked for authenticating repository
33887 Defaults to @samp{""}.
33891 @deftypevr {@code{cgit-configuration} parameter} string branch-sort
33892 Flag which, when set to @samp{age}, enables date ordering in the branch
33893 ref list, and when set @samp{name} enables ordering by branch name.
33895 Defaults to @samp{"name"}.
33899 @deftypevr {@code{cgit-configuration} parameter} string cache-root
33900 Path used to store the cgit cache entries.
33902 Defaults to @samp{"/var/cache/cgit"}.
33906 @deftypevr {@code{cgit-configuration} parameter} integer cache-static-ttl
33907 Number which specifies the time-to-live, in minutes, for the cached
33908 version of repository pages accessed with a fixed SHA1.
33910 Defaults to @samp{-1}.
33914 @deftypevr {@code{cgit-configuration} parameter} integer cache-dynamic-ttl
33915 Number which specifies the time-to-live, in minutes, for the cached
33916 version of repository pages accessed without a fixed SHA1.
33918 Defaults to @samp{5}.
33922 @deftypevr {@code{cgit-configuration} parameter} integer cache-repo-ttl
33923 Number which specifies the time-to-live, in minutes, for the cached
33924 version of the repository summary page.
33926 Defaults to @samp{5}.
33930 @deftypevr {@code{cgit-configuration} parameter} integer cache-root-ttl
33931 Number which specifies the time-to-live, in minutes, for the cached
33932 version of the repository index page.
33934 Defaults to @samp{5}.
33938 @deftypevr {@code{cgit-configuration} parameter} integer cache-scanrc-ttl
33939 Number which specifies the time-to-live, in minutes, for the result of
33940 scanning a path for Git repositories.
33942 Defaults to @samp{15}.
33946 @deftypevr {@code{cgit-configuration} parameter} integer cache-about-ttl
33947 Number which specifies the time-to-live, in minutes, for the cached
33948 version of the repository about page.
33950 Defaults to @samp{15}.
33954 @deftypevr {@code{cgit-configuration} parameter} integer cache-snapshot-ttl
33955 Number which specifies the time-to-live, in minutes, for the cached
33956 version of snapshots.
33958 Defaults to @samp{5}.
33962 @deftypevr {@code{cgit-configuration} parameter} integer cache-size
33963 The maximum number of entries in the cgit cache. When set to @samp{0},
33964 caching is disabled.
33966 Defaults to @samp{0}.
33970 @deftypevr {@code{cgit-configuration} parameter} boolean case-sensitive-sort?
33971 Sort items in the repo list case sensitively.
33973 Defaults to @samp{#t}.
33977 @deftypevr {@code{cgit-configuration} parameter} list clone-prefix
33978 List of common prefixes which, when combined with a repository URL,
33979 generates valid clone URLs for the repository.
33981 Defaults to @samp{()}.
33985 @deftypevr {@code{cgit-configuration} parameter} list clone-url
33986 List of @code{clone-url} templates.
33988 Defaults to @samp{()}.
33992 @deftypevr {@code{cgit-configuration} parameter} file-object commit-filter
33993 Command which will be invoked to format commit messages.
33995 Defaults to @samp{""}.
33999 @deftypevr {@code{cgit-configuration} parameter} string commit-sort
34000 Flag which, when set to @samp{date}, enables strict date ordering in the
34001 commit log, and when set to @samp{topo} enables strict topological
34004 Defaults to @samp{"git log"}.
34008 @deftypevr {@code{cgit-configuration} parameter} file-object css
34009 URL which specifies the css document to include in all cgit pages.
34011 Defaults to @samp{"/share/cgit/cgit.css"}.
34015 @deftypevr {@code{cgit-configuration} parameter} file-object email-filter
34016 Specifies a command which will be invoked to format names and email
34017 address of committers, authors, and taggers, as represented in various
34018 places throughout the cgit interface.
34020 Defaults to @samp{""}.
34024 @deftypevr {@code{cgit-configuration} parameter} boolean embedded?
34025 Flag which, when set to @samp{#t}, will make cgit generate a HTML
34026 fragment suitable for embedding in other HTML pages.
34028 Defaults to @samp{#f}.
34032 @deftypevr {@code{cgit-configuration} parameter} boolean enable-commit-graph?
34033 Flag which, when set to @samp{#t}, will make cgit print an ASCII-art
34034 commit history graph to the left of the commit messages in the
34035 repository log page.
34037 Defaults to @samp{#f}.
34041 @deftypevr {@code{cgit-configuration} parameter} boolean enable-filter-overrides?
34042 Flag which, when set to @samp{#t}, allows all filter settings to be
34043 overridden in repository-specific cgitrc files.
34045 Defaults to @samp{#f}.
34049 @deftypevr {@code{cgit-configuration} parameter} boolean enable-follow-links?
34050 Flag which, when set to @samp{#t}, allows users to follow a file in the
34053 Defaults to @samp{#f}.
34057 @deftypevr {@code{cgit-configuration} parameter} boolean enable-http-clone?
34058 If set to @samp{#t}, cgit will act as an dumb HTTP endpoint for Git
34061 Defaults to @samp{#t}.
34065 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-links?
34066 Flag which, when set to @samp{#t}, will make cgit generate extra links
34067 "summary", "commit", "tree" for each repo in the repository index.
34069 Defaults to @samp{#f}.
34073 @deftypevr {@code{cgit-configuration} parameter} boolean enable-index-owner?
34074 Flag which, when set to @samp{#t}, will make cgit display the owner of
34075 each repo in the repository index.
34077 Defaults to @samp{#t}.
34081 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-filecount?
34082 Flag which, when set to @samp{#t}, will make cgit print the number of
34083 modified files for each commit on the repository log page.
34085 Defaults to @samp{#f}.
34089 @deftypevr {@code{cgit-configuration} parameter} boolean enable-log-linecount?
34090 Flag which, when set to @samp{#t}, will make cgit print the number of
34091 added and removed lines for each commit on the repository log page.
34093 Defaults to @samp{#f}.
34097 @deftypevr {@code{cgit-configuration} parameter} boolean enable-remote-branches?
34098 Flag which, when set to @code{#t}, will make cgit display remote
34099 branches in the summary and refs views.
34101 Defaults to @samp{#f}.
34105 @deftypevr {@code{cgit-configuration} parameter} boolean enable-subject-links?
34106 Flag which, when set to @code{1}, will make cgit use the subject of the
34107 parent commit as link text when generating links to parent commits in
34110 Defaults to @samp{#f}.
34114 @deftypevr {@code{cgit-configuration} parameter} boolean enable-html-serving?
34115 Flag which, when set to @samp{#t}, will make cgit use the subject of the
34116 parent commit as link text when generating links to parent commits in
34119 Defaults to @samp{#f}.
34123 @deftypevr {@code{cgit-configuration} parameter} boolean enable-tree-linenumbers?
34124 Flag which, when set to @samp{#t}, will make cgit generate linenumber
34125 links for plaintext blobs printed in the tree view.
34127 Defaults to @samp{#t}.
34131 @deftypevr {@code{cgit-configuration} parameter} boolean enable-git-config?
34132 Flag which, when set to @samp{#f}, will allow cgit to use Git config to
34133 set any repo specific settings.
34135 Defaults to @samp{#f}.
34139 @deftypevr {@code{cgit-configuration} parameter} file-object favicon
34140 URL used as link to a shortcut icon for cgit.
34142 Defaults to @samp{"/favicon.ico"}.
34146 @deftypevr {@code{cgit-configuration} parameter} string footer
34147 The content of the file specified with this option will be included
34148 verbatim at the bottom of all pages (i.e.@: it replaces the standard
34149 "generated by..."@: message).
34151 Defaults to @samp{""}.
34155 @deftypevr {@code{cgit-configuration} parameter} string head-include
34156 The content of the file specified with this option will be included
34157 verbatim in the HTML HEAD section on all pages.
34159 Defaults to @samp{""}.
34163 @deftypevr {@code{cgit-configuration} parameter} string header
34164 The content of the file specified with this option will be included
34165 verbatim at the top of all pages.
34167 Defaults to @samp{""}.
34171 @deftypevr {@code{cgit-configuration} parameter} file-object include
34172 Name of a configfile to include before the rest of the current config-
34175 Defaults to @samp{""}.
34179 @deftypevr {@code{cgit-configuration} parameter} string index-header
34180 The content of the file specified with this option will be included
34181 verbatim above the repository index.
34183 Defaults to @samp{""}.
34187 @deftypevr {@code{cgit-configuration} parameter} string index-info
34188 The content of the file specified with this option will be included
34189 verbatim below the heading on the repository index page.
34191 Defaults to @samp{""}.
34195 @deftypevr {@code{cgit-configuration} parameter} boolean local-time?
34196 Flag which, if set to @samp{#t}, makes cgit print commit and tag times
34197 in the servers timezone.
34199 Defaults to @samp{#f}.
34203 @deftypevr {@code{cgit-configuration} parameter} file-object logo
34204 URL which specifies the source of an image which will be used as a logo
34207 Defaults to @samp{"/share/cgit/cgit.png"}.
34211 @deftypevr {@code{cgit-configuration} parameter} string logo-link
34212 URL loaded when clicking on the cgit logo image.
34214 Defaults to @samp{""}.
34218 @deftypevr {@code{cgit-configuration} parameter} file-object owner-filter
34219 Command which will be invoked to format the Owner column of the main
34222 Defaults to @samp{""}.
34226 @deftypevr {@code{cgit-configuration} parameter} integer max-atom-items
34227 Number of items to display in atom feeds view.
34229 Defaults to @samp{10}.
34233 @deftypevr {@code{cgit-configuration} parameter} integer max-commit-count
34234 Number of entries to list per page in "log" view.
34236 Defaults to @samp{50}.
34240 @deftypevr {@code{cgit-configuration} parameter} integer max-message-length
34241 Number of commit message characters to display in "log" view.
34243 Defaults to @samp{80}.
34247 @deftypevr {@code{cgit-configuration} parameter} integer max-repo-count
34248 Specifies the number of entries to list per page on the repository index
34251 Defaults to @samp{50}.
34255 @deftypevr {@code{cgit-configuration} parameter} integer max-repodesc-length
34256 Specifies the maximum number of repo description characters to display
34257 on the repository index page.
34259 Defaults to @samp{80}.
34263 @deftypevr {@code{cgit-configuration} parameter} integer max-blob-size
34264 Specifies the maximum size of a blob to display HTML for in KBytes.
34266 Defaults to @samp{0}.
34270 @deftypevr {@code{cgit-configuration} parameter} string max-stats
34271 Maximum statistics period. Valid values are @samp{week},@samp{month},
34272 @samp{quarter} and @samp{year}.
34274 Defaults to @samp{""}.
34278 @deftypevr {@code{cgit-configuration} parameter} mimetype-alist mimetype
34279 Mimetype for the specified filename extension.
34281 Defaults to @samp{((gif "image/gif") (html "text/html") (jpg
34282 "image/jpeg") (jpeg "image/jpeg") (pdf "application/pdf") (png
34283 "image/png") (svg "image/svg+xml"))}.
34287 @deftypevr {@code{cgit-configuration} parameter} file-object mimetype-file
34288 Specifies the file to use for automatic mimetype lookup.
34290 Defaults to @samp{""}.
34294 @deftypevr {@code{cgit-configuration} parameter} string module-link
34295 Text which will be used as the formatstring for a hyperlink when a
34296 submodule is printed in a directory listing.
34298 Defaults to @samp{""}.
34302 @deftypevr {@code{cgit-configuration} parameter} boolean nocache?
34303 If set to the value @samp{#t} caching will be disabled.
34305 Defaults to @samp{#f}.
34309 @deftypevr {@code{cgit-configuration} parameter} boolean noplainemail?
34310 If set to @samp{#t} showing full author email addresses will be
34313 Defaults to @samp{#f}.
34317 @deftypevr {@code{cgit-configuration} parameter} boolean noheader?
34318 Flag which, when set to @samp{#t}, will make cgit omit the standard
34319 header on all pages.
34321 Defaults to @samp{#f}.
34325 @deftypevr {@code{cgit-configuration} parameter} project-list project-list
34326 A list of subdirectories inside of @code{repository-directory}, relative
34327 to it, that should loaded as Git repositories. An empty list means that
34328 all subdirectories will be loaded.
34330 Defaults to @samp{()}.
34334 @deftypevr {@code{cgit-configuration} parameter} file-object readme
34335 Text which will be used as default value for @code{cgit-repo-readme}.
34337 Defaults to @samp{""}.
34341 @deftypevr {@code{cgit-configuration} parameter} boolean remove-suffix?
34342 If set to @code{#t} and @code{repository-directory} is enabled, if any
34343 repositories are found with a suffix of @code{.git}, this suffix will be
34344 removed for the URL and name.
34346 Defaults to @samp{#f}.
34350 @deftypevr {@code{cgit-configuration} parameter} integer renamelimit
34351 Maximum number of files to consider when detecting renames.
34353 Defaults to @samp{-1}.
34357 @deftypevr {@code{cgit-configuration} parameter} string repository-sort
34358 The way in which repositories in each section are sorted.
34360 Defaults to @samp{""}.
34364 @deftypevr {@code{cgit-configuration} parameter} robots-list robots
34365 Text used as content for the @code{robots} meta-tag.
34367 Defaults to @samp{("noindex" "nofollow")}.
34371 @deftypevr {@code{cgit-configuration} parameter} string root-desc
34372 Text printed below the heading on the repository index page.
34374 Defaults to @samp{"a fast webinterface for the git dscm"}.
34378 @deftypevr {@code{cgit-configuration} parameter} string root-readme
34379 The content of the file specified with this option will be included
34380 verbatim below the ``about'' link on the repository index page.
34382 Defaults to @samp{""}.
34386 @deftypevr {@code{cgit-configuration} parameter} string root-title
34387 Text printed as heading on the repository index page.
34389 Defaults to @samp{""}.
34393 @deftypevr {@code{cgit-configuration} parameter} boolean scan-hidden-path
34394 If set to @samp{#t} and repository-directory is enabled,
34395 repository-directory will recurse into directories whose name starts
34396 with a period. Otherwise, repository-directory will stay away from such
34397 directories, considered as ``hidden''. Note that this does not apply to
34398 the @file{.git} directory in non-bare repos.
34400 Defaults to @samp{#f}.
34404 @deftypevr {@code{cgit-configuration} parameter} list snapshots
34405 Text which specifies the default set of snapshot formats that cgit
34406 generates links for.
34408 Defaults to @samp{()}.
34412 @deftypevr {@code{cgit-configuration} parameter} repository-directory repository-directory
34413 Name of the directory to scan for repositories (represents
34416 Defaults to @samp{"/srv/git"}.
34420 @deftypevr {@code{cgit-configuration} parameter} string section
34421 The name of the current repository section - all repositories defined
34422 after this option will inherit the current section name.
34424 Defaults to @samp{""}.
34428 @deftypevr {@code{cgit-configuration} parameter} string section-sort
34429 Flag which, when set to @samp{1}, will sort the sections on the
34430 repository listing by name.
34432 Defaults to @samp{""}.
34436 @deftypevr {@code{cgit-configuration} parameter} integer section-from-path
34437 A number which, if defined prior to repository-directory, specifies how
34438 many path elements from each repo path to use as a default section name.
34440 Defaults to @samp{0}.
34444 @deftypevr {@code{cgit-configuration} parameter} boolean side-by-side-diffs?
34445 If set to @samp{#t} shows side-by-side diffs instead of unidiffs per
34448 Defaults to @samp{#f}.
34452 @deftypevr {@code{cgit-configuration} parameter} file-object source-filter
34453 Specifies a command which will be invoked to format plaintext blobs in
34456 Defaults to @samp{""}.
34460 @deftypevr {@code{cgit-configuration} parameter} integer summary-branches
34461 Specifies the number of branches to display in the repository ``summary''
34464 Defaults to @samp{10}.
34468 @deftypevr {@code{cgit-configuration} parameter} integer summary-log
34469 Specifies the number of log entries to display in the repository
34472 Defaults to @samp{10}.
34476 @deftypevr {@code{cgit-configuration} parameter} integer summary-tags
34477 Specifies the number of tags to display in the repository ``summary''
34480 Defaults to @samp{10}.
34484 @deftypevr {@code{cgit-configuration} parameter} string strict-export
34485 Filename which, if specified, needs to be present within the repository
34486 for cgit to allow access to that repository.
34488 Defaults to @samp{""}.
34492 @deftypevr {@code{cgit-configuration} parameter} string virtual-root
34493 URL which, if specified, will be used as root for all cgit links.
34495 Defaults to @samp{"/"}.
34499 @deftypevr {@code{cgit-configuration} parameter} repository-cgit-configuration-list repositories
34500 A list of @dfn{cgit-repo} records to use with config.
34502 Defaults to @samp{()}.
34504 Available @code{repository-cgit-configuration} fields are:
34506 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list snapshots
34507 A mask of snapshot formats for this repo that cgit generates links for,
34508 restricted by the global @code{snapshots} setting.
34510 Defaults to @samp{()}.
34514 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object source-filter
34515 Override the default @code{source-filter}.
34517 Defaults to @samp{""}.
34521 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string url
34522 The relative URL used to access the repository.
34524 Defaults to @samp{""}.
34528 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object about-filter
34529 Override the default @code{about-filter}.
34531 Defaults to @samp{""}.
34535 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string branch-sort
34536 Flag which, when set to @samp{age}, enables date ordering in the branch
34537 ref list, and when set to @samp{name} enables ordering by branch name.
34539 Defaults to @samp{""}.
34543 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list clone-url
34544 A list of URLs which can be used to clone repo.
34546 Defaults to @samp{()}.
34550 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object commit-filter
34551 Override the default @code{commit-filter}.
34553 Defaults to @samp{""}.
34557 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string commit-sort
34558 Flag which, when set to @samp{date}, enables strict date ordering in the
34559 commit log, and when set to @samp{topo} enables strict topological
34562 Defaults to @samp{""}.
34566 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string defbranch
34567 The name of the default branch for this repository. If no such branch
34568 exists in the repository, the first branch name (when sorted) is used as
34569 default instead. By default branch pointed to by HEAD, or ``master'' if
34570 there is no suitable HEAD.
34572 Defaults to @samp{""}.
34576 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string desc
34577 The value to show as repository description.
34579 Defaults to @samp{""}.
34583 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string homepage
34584 The value to show as repository homepage.
34586 Defaults to @samp{""}.
34590 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object email-filter
34591 Override the default @code{email-filter}.
34593 Defaults to @samp{""}.
34597 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-commit-graph?
34598 A flag which can be used to disable the global setting
34599 @code{enable-commit-graph?}.
34601 Defaults to @samp{disabled}.
34605 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-filecount?
34606 A flag which can be used to disable the global setting
34607 @code{enable-log-filecount?}.
34609 Defaults to @samp{disabled}.
34613 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-log-linecount?
34614 A flag which can be used to disable the global setting
34615 @code{enable-log-linecount?}.
34617 Defaults to @samp{disabled}.
34621 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-remote-branches?
34622 Flag which, when set to @code{#t}, will make cgit display remote
34623 branches in the summary and refs views.
34625 Defaults to @samp{disabled}.
34629 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-subject-links?
34630 A flag which can be used to override the global setting
34631 @code{enable-subject-links?}.
34633 Defaults to @samp{disabled}.
34637 @deftypevr {@code{repository-cgit-configuration} parameter} maybe-repo-boolean enable-html-serving?
34638 A flag which can be used to override the global setting
34639 @code{enable-html-serving?}.
34641 Defaults to @samp{disabled}.
34645 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean hide?
34646 Flag which, when set to @code{#t}, hides the repository from the
34649 Defaults to @samp{#f}.
34653 @deftypevr {@code{repository-cgit-configuration} parameter} repo-boolean ignore?
34654 Flag which, when set to @samp{#t}, ignores the repository.
34656 Defaults to @samp{#f}.
34660 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object logo
34661 URL which specifies the source of an image which will be used as a logo
34662 on this repo’s pages.
34664 Defaults to @samp{""}.
34668 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string logo-link
34669 URL loaded when clicking on the cgit logo image.
34671 Defaults to @samp{""}.
34675 @deftypevr {@code{repository-cgit-configuration} parameter} repo-file-object owner-filter
34676 Override the default @code{owner-filter}.
34678 Defaults to @samp{""}.
34682 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string module-link
34683 Text which will be used as the formatstring for a hyperlink when a
34684 submodule is printed in a directory listing. The arguments for the
34685 formatstring are the path and SHA1 of the submodule commit.
34687 Defaults to @samp{""}.
34691 @deftypevr {@code{repository-cgit-configuration} parameter} module-link-path module-link-path
34692 Text which will be used as the formatstring for a hyperlink when a
34693 submodule with the specified subdirectory path is printed in a directory
34696 Defaults to @samp{()}.
34700 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string max-stats
34701 Override the default maximum statistics period.
34703 Defaults to @samp{""}.
34707 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string name
34708 The value to show as repository name.
34710 Defaults to @samp{""}.
34714 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string owner
34715 A value used to identify the owner of the repository.
34717 Defaults to @samp{""}.
34721 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string path
34722 An absolute path to the repository directory.
34724 Defaults to @samp{""}.
34728 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string readme
34729 A path (relative to repo) which specifies a file to include verbatim as
34730 the ``About'' page for this repo.
34732 Defaults to @samp{""}.
34736 @deftypevr {@code{repository-cgit-configuration} parameter} repo-string section
34737 The name of the current repository section - all repositories defined
34738 after this option will inherit the current section name.
34740 Defaults to @samp{""}.
34744 @deftypevr {@code{repository-cgit-configuration} parameter} repo-list extra-options
34745 Extra options will be appended to cgitrc file.
34747 Defaults to @samp{()}.
34753 @deftypevr {@code{cgit-configuration} parameter} list extra-options
34754 Extra options will be appended to cgitrc file.
34756 Defaults to @samp{()}.
34761 @c %end of fragment
34763 However, it could be that you just want to get a @code{cgitrc} up and
34764 running. In that case, you can pass an @code{opaque-cgit-configuration}
34765 as a record to @code{cgit-service-type}. As its name indicates, an
34766 opaque configuration does not have easy reflective capabilities.
34768 Available @code{opaque-cgit-configuration} fields are:
34770 @deftypevr {@code{opaque-cgit-configuration} parameter} package cgit
34774 @deftypevr {@code{opaque-cgit-configuration} parameter} string string
34775 The contents of the @code{cgitrc}, as a string.
34778 For example, if your @code{cgitrc} is just the empty string, you
34779 could instantiate a cgit service like this:
34782 (service cgit-service-type
34783 (opaque-cgit-configuration
34787 @subsubheading Gitolite Service
34789 @cindex Gitolite service
34790 @cindex Git, hosting
34791 @uref{https://gitolite.com/gitolite/, Gitolite} is a tool for hosting Git
34792 repositories on a central server.
34794 Gitolite can handle multiple repositories and users, and supports flexible
34795 configuration of the permissions for the users on the repositories.
34797 The following example will configure Gitolite using the default @code{git}
34798 user, and the provided SSH public key.
34801 (service gitolite-service-type
34802 (gitolite-configuration
34803 (admin-pubkey (plain-file
34805 "ssh-rsa AAAA... guix@@example.com"))))
34808 Gitolite is configured through a special admin repository which you can clone,
34809 for example, if you setup Gitolite on @code{example.com}, you would run the
34810 following command to clone the admin repository.
34813 git clone git@@example.com:gitolite-admin
34816 When the Gitolite service is activated, the provided @code{admin-pubkey} will
34817 be inserted in to the @file{keydir} directory in the gitolite-admin
34818 repository. If this results in a change in the repository, it will be
34819 committed using the message ``gitolite setup by GNU Guix''.
34821 @deftp {Data Type} gitolite-configuration
34822 Data type representing the configuration for @code{gitolite-service-type}.
34825 @item @code{package} (default: @var{gitolite})
34826 Gitolite package to use.
34828 @item @code{user} (default: @var{git})
34829 User to use for Gitolite. This will be user that you use when accessing
34832 @item @code{group} (default: @var{git})
34833 Group to use for Gitolite.
34835 @item @code{home-directory} (default: @var{"/var/lib/gitolite"})
34836 Directory in which to store the Gitolite configuration and repositories.
34838 @item @code{rc-file} (default: @var{(gitolite-rc-file)})
34839 A ``file-like'' object (@pxref{G-Expressions, file-like objects}),
34840 representing the configuration for Gitolite.
34842 @item @code{admin-pubkey} (default: @var{#f})
34843 A ``file-like'' object (@pxref{G-Expressions, file-like objects}) used to
34844 setup Gitolite. This will be inserted in to the @file{keydir} directory
34845 within the gitolite-admin repository.
34847 To specify the SSH key as a string, use the @code{plain-file} function.
34850 (plain-file "yourname.pub" "ssh-rsa AAAA... guix@@example.com")
34856 @deftp {Data Type} gitolite-rc-file
34857 Data type representing the Gitolite RC file.
34860 @item @code{umask} (default: @code{#o0077})
34861 This controls the permissions Gitolite sets on the repositories and their
34864 A value like @code{#o0027} will give read access to the group used by Gitolite
34865 (by default: @code{git}). This is necessary when using Gitolite with software
34866 like cgit or gitweb.
34868 @item @code{unsafe-pattern} (default: @code{#f})
34869 An optional Perl regular expression for catching unsafe configurations in
34870 the configuration file. See
34871 @uref{https://gitolite.com/gitolite/git-config.html#compensating-for-unsafe_patt,
34872 Gitolite's documentation} for more information.
34874 When the value is not @code{#f}, it should be a string containing a Perl
34875 regular expression, such as @samp{"[`~#\$\&()|;<>]"}, which is the default
34876 value used by gitolite. It rejects any special character in configuration
34877 that might be interpreted by a shell, which is useful when sharing the
34878 administration burden with other people that do not otherwise have shell
34879 access on the server.
34881 @item @code{git-config-keys} (default: @code{""})
34882 Gitolite allows you to set git config values using the @samp{config}
34883 keyword. This setting allows control over the config keys to accept.
34885 @item @code{roles} (default: @code{'(("READERS" . 1) ("WRITERS" . ))})
34886 Set the role names allowed to be used by users running the perms command.
34888 @item @code{enable} (default: @code{'("help" "desc" "info" "perms" "writable" "ssh-authkeys" "git-config" "daemon" "gitweb")})
34889 This setting controls the commands and features to enable within Gitolite.
34895 @subsubheading Gitile Service
34897 @cindex Gitile service
34899 @uref{https://git.lepiller.eu/gitile, Gitile} is a Git forge for viewing
34900 public git repository contents from a web browser.
34902 Gitile works best in collaboration with Gitolite, and will serve the public
34903 repositories from Gitolite by default. The service should listen only on
34904 a local port, and a webserver should be configured to serve static resources.
34905 The gitile service provides an easy way to extend the Nginx service for
34906 that purpose (@pxref{NGINX}).
34908 The following example will configure Gitile to serve repositories from a
34909 custom location, with some default messages for the home page and the
34913 (service gitile-service-type
34914 (gitile-configuration
34915 (repositories "/srv/git")
34916 (base-git-url "https://myweb.site/git")
34917 (index-title "My git repositories")
34918 (intro '((p "This is all my public work!")))
34919 (footer '((p "This is the end")))
34920 (nginx-server-block
34921 (nginx-server-configuration
34923 "/etc/letsencrypt/live/myweb.site/fullchain.pem")
34924 (ssl-certificate-key
34925 "/etc/letsencrypt/live/myweb.site/privkey.pem")
34926 (listen '("443 ssl http2" "[::]:443 ssl http2"))
34929 ;; Allow for https anonymous fetch on /git/ urls.
34930 (git-http-nginx-location-configuration
34931 (git-http-configuration
34933 (git-root "/var/lib/gitolite/repositories")))))))))
34936 In addition to the configuration record, you should configure your git
34937 repositories to contain some optional information. First, your public
34938 repositories need to contain the @file{git-daemon-export-ok} magic file
34939 that allows Git to export the repository. Gitile uses the presence of this
34940 file to detect public repositories it should make accessible. To do so with
34941 Gitolite for instance, modify your @file{conf/gitolite.conf} to include
34942 this in the repositories you want to make public:
34949 In addition, Gitile can read the repository configuration to display more
34950 information on the repository. Gitile uses the gitweb namespace for its
34951 configuration. As an example, you can use the following in your
34952 @file{conf/gitolite.conf}:
34957 desc = A long description, optionally with <i>HTML</i>, shown on the index page
34958 config gitweb.name = The Foo Project
34959 config gitweb.synopsis = A short description, shown on the main page of the project
34962 Do not forget to commit and push these changes once you are satisfied. You
34963 may need to change your gitolite configuration to allow the previous
34964 configuration options to be set. One way to do that is to add the
34965 following service definition:
34968 (service gitolite-service-type
34969 (gitolite-configuration
34970 (admin-pubkey (local-file "key.pub"))
34974 ;; Allow to set any configuration key
34975 (git-config-keys ".*")
34976 ;; Allow any text as a valid configuration value
34977 (unsafe-patt "^$")))))
34980 @deftp {Data Type} gitile-configuration
34981 Data type representing the configuration for @code{gitile-service-type}.
34984 @item @code{package} (default: @var{gitile})
34985 Gitile package to use.
34987 @item @code{host} (default: @code{"localhost"})
34988 The host on which gitile is listening.
34990 @item @code{port} (default: @code{8080})
34991 The port on which gitile is listening.
34993 @item @code{database} (default: @code{"/var/lib/gitile/gitile-db.sql"})
34994 The location of the database.
34996 @item @code{repositories} (default: @code{"/var/lib/gitolite/repositories"})
34997 The location of the repositories. Note that only public repositories will
34998 be shown by Gitile. To make a repository public, add an empty
34999 @file{git-daemon-export-ok} file at the root of that repository.
35001 @item @code{base-git-url}
35002 The base git url that will be used to show clone commands.
35004 @item @code{index-title} (default: @code{"Index"})
35005 The page title for the index page that lists all the available repositories.
35007 @item @code{intro} (default: @code{'()})
35008 The intro content, as a list of sxml expressions. This is shown above the list
35009 of repositories, on the index page.
35011 @item @code{footer} (default: @code{'()})
35012 The footer content, as a list of sxml expressions. This is shown on every
35013 page served by Gitile.
35015 @item @code{nginx-server-block}
35016 An nginx server block that will be extended and used as a reverse proxy by
35017 Gitile to serve its pages, and as a normal web server to serve its assets.
35019 You can use this block to add more custom URLs to your domain, such as a
35020 @code{/git/} URL for anonymous clones, or serving any other files you would
35026 @node Game Services
35027 @subsection Game Services
35029 @subsubheading The Battle for Wesnoth Service
35031 @uref{https://wesnoth.org, The Battle for Wesnoth} is a fantasy, turn
35032 based tactical strategy game, with several single player campaigns, and
35033 multiplayer games (both networked and local).
35035 @defvar {Scheme Variable} wesnothd-service-type
35036 Service type for the wesnothd service. Its value must be a
35037 @code{wesnothd-configuration} object. To run wesnothd in the default
35038 configuration, instantiate it as:
35041 (service wesnothd-service-type)
35045 @deftp {Data Type} wesnothd-configuration
35046 Data type representing the configuration of @command{wesnothd}.
35049 @item @code{package} (default: @code{wesnoth-server})
35050 The wesnoth server package to use.
35052 @item @code{port} (default: @code{15000})
35053 The port to bind the server to.
35058 @node PAM Mount Service
35059 @subsection PAM Mount Service
35062 The @code{(gnu services pam-mount)} module provides a service allowing
35063 users to mount volumes when they log in. It should be able to mount any
35064 volume format supported by the system.
35066 @defvar {Scheme Variable} pam-mount-service-type
35067 Service type for PAM Mount support.
35070 @deftp {Data Type} pam-mount-configuration
35071 Data type representing the configuration of PAM Mount.
35073 It takes the following parameters:
35077 The configuration rules that will be used to generate
35078 @file{/etc/security/pam_mount.conf.xml}.
35080 The configuration rules are SXML elements (@pxref{SXML,,, guile, GNU
35081 Guile Reference Manual}), and the default ones don't mount anything for
35085 `((debug (@@ (enable "0")))
35086 (mntoptions (@@ (allow ,(string-join
35087 '("nosuid" "nodev" "loop"
35088 "encryption" "fsck" "nonempty"
35089 "allow_root" "allow_other")
35091 (mntoptions (@@ (require "nosuid,nodev")))
35092 (logout (@@ (wait "0")
35096 (mkmountpoint (@@ (enable "1")
35100 Some @code{volume} elements must be added to automatically mount volumes
35101 at login. Here's an example allowing the user @code{alice} to mount her
35102 encrypted @env{HOME} directory and allowing the user @code{bob} to mount
35103 the partition where he stores his data:
35106 (define pam-mount-rules
35107 `((debug (@@ (enable "0")))
35108 (volume (@@ (user "alice")
35111 (mountpoint "/home/alice")))
35112 (volume (@@ (user "bob")
35115 (mountpoint "/home/bob/data")
35116 (options "defaults,autodefrag,compress")))
35117 (mntoptions (@@ (allow ,(string-join
35118 '("nosuid" "nodev" "loop"
35119 "encryption" "fsck" "nonempty"
35120 "allow_root" "allow_other")
35122 (mntoptions (@@ (require "nosuid,nodev")))
35123 (logout (@@ (wait "0")
35127 (mkmountpoint (@@ (enable "1")
35128 (remove "true")))))
35130 (service pam-mount-service-type
35131 (pam-mount-configuration
35132 (rules pam-mount-rules)))
35135 The complete list of possible options can be found in the man page for
35136 @uref{http://pam-mount.sourceforge.net/pam_mount.conf.5.html, pam_mount.conf}.
35141 @node Guix Services
35142 @subsection Guix Services
35144 @subsubheading Guix Build Coordinator
35145 The @uref{https://git.cbaines.net/guix/build-coordinator/,Guix Build
35146 Coordinator} aids in distributing derivation builds among machines
35147 running an @dfn{agent}. The build daemon is still used to build the
35148 derivations, but the Guix Build Coordinator manages allocating builds
35149 and working with the results.
35151 The Guix Build Coordinator consists of one @dfn{coordinator}, and one or
35152 more connected @dfn{agent} processes. The coordinator process handles
35153 clients submitting builds, and allocating builds to agents. The agent
35154 processes talk to a build daemon to actually perform the builds, then
35155 send the results back to the coordinator.
35157 There is a script to run the coordinator component of the Guix Build
35158 Coordinator, but the Guix service uses a custom Guile script instead, to
35159 provide better integration with G-expressions used in the configuration.
35161 @defvar {Scheme Variable} guix-build-coordinator-service-type
35162 Service type for the Guix Build Coordinator. Its value must be a
35163 @code{guix-build-coordinator-configuration} object.
35166 @deftp {Data Type} guix-build-coordinator-configuration
35167 Data type representing the configuration of the Guix Build Coordinator.
35170 @item @code{package} (default: @code{guix-build-coordinator})
35171 The Guix Build Coordinator package to use.
35173 @item @code{user} (default: @code{"guix-build-coordinator"})
35174 The system user to run the service as.
35176 @item @code{group} (default: @code{"guix-build-coordinator"})
35177 The system group to run the service as.
35179 @item @code{database-uri-string} (default: @code{"sqlite:///var/lib/guix-build-coordinator/guix_build_coordinator.db"})
35180 The URI to use for the database.
35182 @item @code{agent-communication-uri} (default: @code{"http://0.0.0.0:8745"})
35183 The URI describing how to listen to requests from agent processes.
35185 @item @code{client-communication-uri} (default: @code{"http://127.0.0.1:8746"})
35186 The URI describing how to listen to requests from clients. The client
35187 API allows submitting builds and currently isn't authenticated, so take
35188 care when configuring this value.
35190 @item @code{allocation-strategy} (default: @code{#~basic-build-allocation-strategy})
35191 A G-expression for the allocation strategy to be used. This is a
35192 procedure that takes the datastore as an argument and populates the
35193 allocation plan in the database.
35195 @item @code{hooks} (default: @var{'()})
35196 An association list of hooks. These provide a way to execute arbitrary
35197 code upon certain events, like a build result being processed.
35199 @item @code{parallel-hooks} (default: @var{'()})
35200 Hooks can be configured to run in parallel. This parameter is an
35201 association list of hooks to do in parallel, where the key is the symbol
35202 for the hook and the value is the number of threads to run.
35204 @item @code{guile} (default: @code{guile-3.0-latest})
35205 The Guile package with which to run the Guix Build Coordinator.
35210 @defvar {Scheme Variable} guix-build-coordinator-agent-service-type
35211 Service type for a Guix Build Coordinator agent. Its value must be a
35212 @code{guix-build-coordinator-agent-configuration} object.
35215 @deftp {Data Type} guix-build-coordinator-agent-configuration
35216 Data type representing the configuration a Guix Build Coordinator agent.
35219 @item @code{package} (default: @code{guix-build-coordinator/agent-only})
35220 The Guix Build Coordinator package to use.
35222 @item @code{user} (default: @code{"guix-build-coordinator-agent"})
35223 The system user to run the service as.
35225 @item @code{coordinator} (default: @code{"http://localhost:8745"})
35226 The URI to use when connecting to the coordinator.
35228 @item @code{authentication}
35229 Record describing how this agent should authenticate with the
35230 coordinator. Possible record types are described below.
35232 @item @code{systems} (default: @code{#f})
35233 The systems for which this agent should fetch builds. The agent process
35234 will use the current system it's running on as the default.
35236 @item @code{max-parallel-builds} (default: @code{1})
35237 The number of builds to perform in parallel.
35239 @item @code{max-1min-load-average} (default: @code{#f})
35240 Load average value to look at when considering starting new builds, if
35241 the 1 minute load average exceeds this value, the agent will wait before
35242 starting new builds.
35244 This will be unspecified if the value is @code{#f}, and the agent will
35245 use the number of cores reported by the system as the max 1 minute load
35248 @item @code{derivation-substitute-urls} (default: @code{#f})
35249 URLs from which to attempt to fetch substitutes for derivations, if the
35250 derivations aren't already available.
35252 @item @code{non-derivation-substitute-urls} (default: @code{#f})
35253 URLs from which to attempt to fetch substitutes for build inputs, if the
35254 input store items aren't already available.
35259 @deftp {Data Type} guix-build-coordinator-agent-password-auth
35260 Data type representing an agent authenticating with a coordinator via a
35265 The UUID of the agent. This should be generated by the coordinator
35266 process, stored in the coordinator database, and used by the intended
35269 @item @code{password}
35270 The password to use when connecting to the coordinator.
35275 @deftp {Data Type} guix-build-coordinator-agent-password-file-auth
35276 Data type representing an agent authenticating with a coordinator via a
35277 UUID and password read from a file.
35281 The UUID of the agent. This should be generated by the coordinator
35282 process, stored in the coordinator database, and used by the intended
35285 @item @code{password-file}
35286 A file containing the password to use when connecting to the
35292 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth
35293 Data type representing an agent authenticating with a coordinator via a
35294 dynamic auth token and agent name.
35297 @item @code{agent-name}
35298 Name of an agent, this is used to match up to an existing entry in the
35299 database if there is one. When no existing entry is found, a new entry
35300 is automatically added.
35303 Dynamic auth token, this is created and stored in the coordinator
35304 database, and is used by the agent to authenticate.
35309 @deftp {Data Type} guix-build-coordinator-agent-dynamic-auth-with-file
35310 Data type representing an agent authenticating with a coordinator via a
35311 dynamic auth token read from a file and agent name.
35314 @item @code{agent-name}
35315 Name of an agent, this is used to match up to an existing entry in the
35316 database if there is one. When no existing entry is found, a new entry
35317 is automatically added.
35319 @item @code{token-file}
35320 File containing the dynamic auth token, this is created and stored in
35321 the coordinator database, and is used by the agent to authenticate.
35326 The Guix Build Coordinator package contains a script to query an
35327 instance of the Guix Data Service for derivations to build, and then
35328 submit builds for those derivations to the coordinator. The service
35329 type below assists in running this script. This is an additional tool
35330 that may be useful when building derivations contained within an
35331 instance of the Guix Data Service.
35333 @defvar {Scheme Variable} guix-build-coordinator-queue-builds-service-type
35334 Service type for the
35335 guix-build-coordinator-queue-builds-from-guix-data-service script. Its
35336 value must be a @code{guix-build-coordinator-queue-builds-configuration}
35340 @deftp {Data Type} guix-build-coordinator-queue-builds-configuration
35341 Data type representing the options to the queue builds from guix data
35345 @item @code{package} (default: @code{guix-build-coordinator})
35346 The Guix Build Coordinator package to use.
35348 @item @code{user} (default: @code{"guix-build-coordinator-queue-builds"})
35349 The system user to run the service as.
35351 @item @code{coordinator} (default: @code{"http://localhost:8746"})
35352 The URI to use when connecting to the coordinator.
35354 @item @code{systems} (default: @code{#f})
35355 The systems for which to fetch derivations to build.
35357 @item @code{systems-and-targets} (default: @code{#f})
35358 An association list of system and target pairs for which to fetch
35359 derivations to build.
35361 @item @code{guix-data-service} (default: @code{"https://data.guix.gnu.org"})
35362 The Guix Data Service instance from which to query to find out about
35363 derivations to build.
35365 @item @code{guix-data-service-build-server-id} (default: @code{#f})
35366 The Guix Data Service build server ID corresponding to the builds being
35367 submitted. Providing this speeds up the submitting of builds as
35368 derivations that have already been submitted can be skipped before
35369 asking the coordinator to build them.
35371 @item @code{processed-commits-file} (default: @code{"/var/cache/guix-build-coordinator-queue-builds/processed-commits"})
35372 A file to record which commits have been processed, to avoid needlessly
35373 processing them again if the service is restarted.
35378 @subsubheading Guix Data Service
35379 The @uref{http://data.guix.gnu.org,Guix Data Service} processes, stores
35380 and provides data about GNU Guix. This includes information about
35381 packages, derivations and lint warnings.
35383 The data is stored in a PostgreSQL database, and available through a web
35386 @defvar {Scheme Variable} guix-data-service-type
35387 Service type for the Guix Data Service. Its value must be a
35388 @code{guix-data-service-configuration} object. The service optionally
35389 extends the getmail service, as the guix-commits mailing list is used to
35390 find out about changes in the Guix git repository.
35393 @deftp {Data Type} guix-data-service-configuration
35394 Data type representing the configuration of the Guix Data Service.
35397 @item @code{package} (default: @code{guix-data-service})
35398 The Guix Data Service package to use.
35400 @item @code{user} (default: @code{"guix-data-service"})
35401 The system user to run the service as.
35403 @item @code{group} (default: @code{"guix-data-service"})
35404 The system group to run the service as.
35406 @item @code{port} (default: @code{8765})
35407 The port to bind the web service to.
35409 @item @code{host} (default: @code{"127.0.0.1"})
35410 The host to bind the web service to.
35412 @item @code{getmail-idle-mailboxes} (default: @code{#f})
35413 If set, this is the list of mailboxes that the getmail service will be
35414 configured to listen to.
35416 @item @code{commits-getmail-retriever-configuration} (default: @code{#f})
35417 If set, this is the @code{getmail-retriever-configuration} object with
35418 which to configure getmail to fetch mail from the guix-commits mailing
35421 @item @code{extra-options} (default: @var{'()})
35422 Extra command line options for @code{guix-data-service}.
35424 @item @code{extra-process-jobs-options} (default: @var{'()})
35425 Extra command line options for @code{guix-data-service-process-jobs}.
35430 @subsubheading Nar Herder
35431 The @uref{https://git.cbaines.net/guix/nar-herder/about/,Nar Herder} is
35432 a utility for managing a collection of nars.
35434 @defvar {Scheme Variable} nar-herder-type
35435 Service type for the Guix Data Service. Its value must be a
35436 @code{nar-herder-configuration} object. The service optionally
35437 extends the getmail service, as the guix-commits mailing list is used to
35438 find out about changes in the Guix git repository.
35441 @deftp {Data Type} nar-herder-configuration
35442 Data type representing the configuration of the Guix Data Service.
35445 @item @code{package} (default: @code{nar-herder})
35446 The Nar Herder package to use.
35448 @item @code{user} (default: @code{"nar-herder"})
35449 The system user to run the service as.
35451 @item @code{group} (default: @code{"nar-herder"})
35452 The system group to run the service as.
35454 @item @code{port} (default: @code{8734})
35455 The port to bind the server to.
35457 @item @code{host} (default: @code{"127.0.0.1"})
35458 The host to bind the server to.
35460 @item @code{mirror} (default: @code{#f})
35461 Optional URL of the other Nar Herder instance which should be mirrored.
35462 This means that this Nar Herder instance will download it's database,
35463 and keep it up to date.
35465 @item @code{database} (default: @code{"/var/lib/nar-herder/nar_herder.db"})
35466 Location for the database. If this Nar Herder instance is mirroring
35467 another, the database will be downloaded if it doesn't exist. If this
35468 Nar Herder instance isn't mirroring another, an empty database will be
35471 @item @code{database-dump} (default: @code{"/var/lib/nar-herder/nar_herder_dump.db"})
35472 Location of the database dump. This is created and regularly updated by
35473 taking a copy of the database. This is the version of the database that
35474 is available to download.
35476 @item @code{storage} (default: @code{#f})
35477 Optional location in which to store nars.
35479 @item @code{storage-limit} (default: @code{"none"})
35480 Limit in bytes for the nars stored in the storage location. This can
35481 also be set to ``none'' so that there is no limit.
35483 When the storage location exceeds this size, nars are removed according
35484 to the nar removal criteria.
35486 @item @code{storage-nar-removal-criteria} (default: @code{'()})
35487 Criteria used to remove nars from the storage location. These are used
35488 in conjunction with the storage limit.
35490 When the storage location exceeds the storage limit size, nars will be
35491 checked against the nar removal criteria and if any of the criteria
35492 match, they will be removed. This will continue until the storage
35493 location is below the storage limit size.
35495 Each criteria is specified by a string, then an equals sign, then
35496 another string. Currently, only one criteria is supported, checking if a
35497 nar is stored on another Nar Herder instance.
35499 @item @code{ttl} (default: @code{#f})
35500 Produce @code{Cache-Control} HTTP headers that advertise a time-to-live
35501 (TTL) of @var{ttl}. @var{ttl} must denote a duration: @code{5d} means 5
35502 days, @code{1m} means 1 month, and so on.
35504 This allows the user's Guix to keep substitute information in cache for
35507 @item @code{negative-ttl} (default: @code{#f})
35508 Similarly produce @code{Cache-Control} HTTP headers to advertise the
35509 time-to-live (TTL) of @emph{negative} lookups---missing store items, for
35510 which the HTTP 404 code is returned. By default, no negative TTL is
35513 @item @code{log-level} (default: @code{'DEBUG})
35514 Log level to use, specify a log level like @code{'INFO} to stop logging
35515 individual requests.
35520 @node Linux Services
35521 @subsection Linux Services
35524 @cindex out of memory killer
35526 @cindex early out of memory daemon
35527 @subsubheading Early OOM Service
35529 @uref{https://github.com/rfjakob/earlyoom,Early OOM}, also known as
35530 Earlyoom, is a minimalist out of memory (OOM) daemon that runs in user
35531 space and provides a more responsive and configurable alternative to the
35532 in-kernel OOM killer. It is useful to prevent the system from becoming
35533 unresponsive when it runs out of memory.
35535 @deffn {Scheme Variable} earlyoom-service-type
35536 The service type for running @command{earlyoom}, the Early OOM daemon.
35537 Its value must be a @code{earlyoom-configuration} object, described
35538 below. The service can be instantiated in its default configuration
35542 (service earlyoom-service-type)
35546 @deftp {Data Type} earlyoom-configuration
35547 This is the configuration record for the @code{earlyoom-service-type}.
35550 @item @code{earlyoom} (default: @var{earlyoom})
35551 The Earlyoom package to use.
35553 @item @code{minimum-available-memory} (default: @code{10})
35554 The threshold for the minimum @emph{available} memory, in percentages.
35556 @item @code{minimum-free-swap} (default: @code{10})
35557 The threshold for the minimum free swap memory, in percentages.
35559 @item @code{prefer-regexp} (default: @code{#f})
35560 A regular expression (as a string) to match the names of the processes
35561 that should be preferably killed.
35563 @item @code{avoid-regexp} (default: @code{#f})
35564 A regular expression (as a string) to match the names of the processes
35565 that should @emph{not} be killed.
35567 @item @code{memory-report-interval} (default: @code{0})
35568 The interval in seconds at which a memory report is printed. It is
35569 disabled by default.
35571 @item @code{ignore-positive-oom-score-adj?} (default: @code{#f})
35572 A boolean indicating whether the positive adjustments set in
35573 @file{/proc/*/oom_score_adj} should be ignored.
35575 @item @code{show-debug-messages?} (default: @code{#f})
35576 A boolean indicating whether debug messages should be printed. The logs
35577 are saved at @file{/var/log/earlyoom.log}.
35579 @item @code{send-notification-command} (default: @code{#f})
35580 This can be used to provide a custom command used for sending
35586 @cindex kernel module loader
35587 @subsubheading Kernel Module Loader Service
35589 The kernel module loader service allows one to load loadable kernel
35590 modules at boot. This is especially useful for modules that don't
35591 autoload and need to be manually loaded, as is the case with
35594 @deffn {Scheme Variable} kernel-module-loader-service-type
35595 The service type for loading loadable kernel modules at boot with
35596 @command{modprobe}. Its value must be a list of strings representing
35597 module names. For example loading the drivers provided by
35598 @code{ddcci-driver-linux}, in debugging mode by passing some module
35599 parameters, can be done as follow:
35602 (use-modules (gnu) (gnu services))
35603 (use-package-modules linux)
35604 (use-service-modules linux)
35606 (define ddcci-config
35607 (plain-file "ddcci.conf"
35608 "options ddcci dyndbg delay=120"))
35612 (services (cons* (service kernel-module-loader-service-type
35613 '("ddcci" "ddcci_backlight"))
35614 (simple-service 'ddcci-config etc-service-type
35615 (list `("modprobe.d/ddcci.conf"
35618 (kernel-loadable-modules (list ddcci-driver-linux)))
35623 @cindex Platform Reliability, Availability and Serviceability daemon
35624 @subsubheading Rasdaemon Service
35626 The Rasdaemon service provides a daemon which monitors platform
35627 @acronym{RAS, Reliability@comma{} Availability@comma{} and Serviceability} reports from
35628 Linux kernel trace events, logging them to syslogd.
35630 Reliability, Availability and Serviceability is a concept used on servers meant
35631 to measure their robustness.
35633 @strong{Relability} is the probability that a system will produce correct
35637 @item Generally measured as Mean Time Between Failures (MTBF), and
35638 @item Enhanced by features that help to avoid, detect and repair hardware
35642 @strong{Availability} is the probability that a system is operational at a
35646 @item Generally measured as a percentage of downtime per a period of time, and
35647 @item Often uses mechanisms to detect and correct hardware faults in runtime.
35650 @strong{Serviceability} is the simplicity and speed with which a system can be
35651 repaired or maintained:
35654 @item Generally measured on Mean Time Between Repair (MTBR).
35658 Among the monitoring measures, the most usual ones include:
35661 @item CPU – detect errors at instruction execution and at L1/L2/L3 caches;
35662 @item Memory – add error correction logic (ECC) to detect and correct errors;
35663 @item I/O – add CRC checksums for transferred data;
35664 @item Storage – RAID, journal file systems, checksums, Self-Monitoring,
35665 Analysis and Reporting Technology (SMART).
35668 By monitoring the number of occurrences of error detections, it is possible to
35669 identify if the probability of hardware errors is increasing, and, on such
35670 case, do a preventive maintenance to replace a degraded component while those
35671 errors are correctable.
35673 For detailed information about the types of error events gathered and how to
35674 make sense of them, see the kernel administrator's guide at
35675 @url{https://www.kernel.org/doc/html/latest/admin-guide/ras.html}.
35677 @defvr {Scheme Variable} rasdaemon-service-type
35678 Service type for the @command{rasdaemon} service. It accepts a
35679 @code{rasdaemon-configuration} object. Instantiating like
35682 (service rasdaemon-service-type)
35685 will load with a default configuration, which monitors all events and logs to
35689 @deftp {Data Type} rasdaemon-configuration
35690 The data type representing the configuration of @command{rasdaemon}.
35693 @item @code{record?} (default: @code{#f})
35695 A boolean indicating whether to record the events in an SQLite database. This
35696 provides a more structured access to the information contained in the log file.
35697 The database location is hard-coded to @file{/var/lib/rasdaemon/ras-mc_event.db}.
35703 @cindex compressed swap
35704 @cindex Compressed RAM-based block devices
35705 @subsubheading Zram Device Service
35707 The Zram device service provides a compressed swap device in system
35708 memory. The Linux Kernel documentation has more information about
35709 @uref{https://www.kernel.org/doc/html/latest/admin-guide/blockdev/zram.html,zram}
35712 @deffn {Scheme Variable} zram-device-service-type
35713 This service creates the zram block device, formats it as swap and
35714 enables it as a swap device. The service's value is a
35715 @code{zram-device-configuration} record.
35717 @deftp {Data Type} zram-device-configuration
35718 This is the data type representing the configuration for the zram-device
35722 @item @code{size} (default @code{"1G"})
35723 This is the amount of space you wish to provide for the zram device. It
35724 accepts a string and can be a number of bytes or use a suffix, eg.:
35725 @code{"512M"} or @code{1024000}.
35726 @item @code{compression-algorithm} (default @code{'lzo})
35727 This is the compression algorithm you wish to use. It is difficult to
35728 list all the possible compression options, but common ones supported by
35729 Guix's Linux Libre Kernel include @code{'lzo}, @code{'lz4} and @code{'zstd}.
35730 @item @code{memory-limit} (default @code{0})
35731 This is the maximum amount of memory which the zram device can use.
35732 Setting it to '0' disables the limit. While it is generally expected
35733 that compression will be 2:1, it is possible that uncompressable data
35734 can be written to swap and this is a method to limit how much memory can
35735 be used. It accepts a string and can be a number of bytes or use a
35736 suffix, eg.: @code{"2G"}.
35737 @item @code{priority} (default @code{#f})
35738 This is the priority of the swap device created from the zram device.
35739 @xref{Swap Space} for a description of swap priorities. You might want
35740 to set a specific priority for the zram device, otherwise it could end
35741 up not being used much for the reasons described there.
35747 @node Hurd Services
35748 @subsection Hurd Services
35750 @defvr {Scheme Variable} hurd-console-service-type
35751 This service starts the fancy @code{VGA} console client on the Hurd.
35753 The service's value is a @code{hurd-console-configuration} record.
35756 @deftp {Data Type} hurd-console-configuration
35757 This is the data type representing the configuration for the
35758 hurd-console-service.
35761 @item @code{hurd} (default: @var{hurd})
35762 The Hurd package to use.
35766 @defvr {Scheme Variable} hurd-getty-service-type
35767 This service starts a tty using the Hurd @code{getty} program.
35769 The service's value is a @code{hurd-getty-configuration} record.
35772 @deftp {Data Type} hurd-getty-configuration
35773 This is the data type representing the configuration for the
35774 hurd-getty-service.
35777 @item @code{hurd} (default: @var{hurd})
35778 The Hurd package to use.
35781 The name of the console this Getty runs on---e.g., @code{"tty1"}.
35783 @item @code{baud-rate} (default: @code{38400})
35784 An integer specifying the baud rate of the tty.
35789 @node Miscellaneous Services
35790 @subsection Miscellaneous Services
35792 @cindex fingerprint
35793 @subsubheading Fingerprint Service
35795 The @code{(gnu services authentication)} module provides a DBus service to
35796 read and identify fingerprints via a fingerprint sensor.
35798 @defvr {Scheme Variable} fprintd-service-type
35799 The service type for @command{fprintd}, which provides the fingerprint
35800 reading capability.
35803 (service fprintd-service-type)
35808 @subsubheading System Control Service
35810 The @code{(gnu services sysctl)} provides a service to configure kernel
35811 parameters at boot.
35813 @defvr {Scheme Variable} sysctl-service-type
35814 The service type for @command{sysctl}, which modifies kernel parameters
35815 under @file{/proc/sys/}. To enable IPv4 forwarding, it can be
35819 (service sysctl-service-type
35820 (sysctl-configuration
35821 (settings '(("net.ipv4.ip_forward" . "1")))))
35824 Since @code{sysctl-service-type} is used in the default lists of
35825 services, @code{%base-services} and @code{%desktop-services}, you can
35826 use @code{modify-services} to change its configuration and add the
35827 kernel parameters that you want (@pxref{Service Reference,
35828 @code{modify-services}}).
35831 (modify-services %base-services
35832 (sysctl-service-type config =>
35833 (sysctl-configuration
35834 (settings (append '(("net.ipv4.ip_forward" . "1"))
35835 %default-sysctl-settings)))))
35840 @deftp {Data Type} sysctl-configuration
35841 The data type representing the configuration of @command{sysctl}.
35844 @item @code{sysctl} (default: @code{(file-append procps "/sbin/sysctl"})
35845 The @command{sysctl} executable to use.
35847 @item @code{settings} (default: @code{%default-sysctl-settings})
35848 An association list specifies kernel parameters and their values.
35852 @defvr {Scheme Variable} %default-sysctl-settings
35853 An association list specifying the default @command{sysctl} parameters
35858 @subsubheading PC/SC Smart Card Daemon Service
35860 The @code{(gnu services security-token)} module provides the following service
35861 to run @command{pcscd}, the PC/SC Smart Card Daemon. @command{pcscd} is the
35862 daemon program for pcsc-lite and the MuscleCard framework. It is a resource
35863 manager that coordinates communications with smart card readers, smart cards
35864 and cryptographic tokens that are connected to the system.
35866 @defvr {Scheme Variable} pcscd-service-type
35867 Service type for the @command{pcscd} service. Its value must be a
35868 @code{pcscd-configuration} object. To run pcscd in the default
35869 configuration, instantiate it as:
35872 (service pcscd-service-type)
35876 @deftp {Data Type} pcscd-configuration
35877 The data type representing the configuration of @command{pcscd}.
35880 @item @code{pcsc-lite} (default: @code{pcsc-lite})
35881 The pcsc-lite package that provides pcscd.
35882 @item @code{usb-drivers} (default: @code{(list ccid)})
35883 List of packages that provide USB drivers to pcscd. Drivers are expected to be
35884 under @file{pcsc/drivers} in the store directory of the package.
35889 @subsubheading Lirc Service
35891 The @code{(gnu services lirc)} module provides the following service.
35893 @deffn {Scheme Procedure} lirc-service [#:lirc lirc] @
35894 [#:device #f] [#:driver #f] [#:config-file #f] @
35895 [#:extra-options '()]
35896 Return a service that runs @url{http://www.lirc.org,LIRC}, a daemon that
35897 decodes infrared signals from remote controls.
35899 Optionally, @var{device}, @var{driver} and @var{config-file}
35900 (configuration file name) may be specified. See @command{lircd} manual
35903 Finally, @var{extra-options} is a list of additional command-line options
35904 passed to @command{lircd}.
35908 @subsubheading Spice Service
35910 The @code{(gnu services spice)} module provides the following service.
35912 @deffn {Scheme Procedure} spice-vdagent-service [#:spice-vdagent]
35913 Returns a service that runs @url{https://www.spice-space.org,VDAGENT}, a daemon
35914 that enables sharing the clipboard with a vm and setting the guest display
35915 resolution when the graphical console window resizes.
35918 @cindex inputattach
35919 @subsubheading inputattach Service
35921 @cindex tablet input, for Xorg
35922 @cindex touchscreen input, for Xorg
35923 The @uref{https://linuxwacom.github.io/, inputattach} service allows you to
35924 use input devices such as Wacom tablets, touchscreens, or joysticks with the
35925 Xorg display server.
35927 @deffn {Scheme Variable} inputattach-service-type
35928 Type of a service that runs @command{inputattach} on a device and
35929 dispatches events from it.
35932 @deftp {Data Type} inputattach-configuration
35934 @item @code{device-type} (default: @code{"wacom"})
35935 The type of device to connect to. Run @command{inputattach --help}, from the
35936 @code{inputattach} package, to see the list of supported device types.
35938 @item @code{device} (default: @code{"/dev/ttyS0"})
35939 The device file to connect to the device.
35941 @item @code{baud-rate} (default: @code{#f})
35942 Baud rate to use for the serial connection.
35943 Should be a number or @code{#f}.
35945 @item @code{log-file} (default: @code{#f})
35946 If true, this must be the name of a file to log messages to.
35950 @subsubheading Dictionary Service
35952 The @code{(gnu services dict)} module provides the following service:
35954 @defvr {Scheme Variable} dicod-service-type
35955 This is the type of the service that runs the @command{dicod} daemon, an
35956 implementation of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
35959 @deffn {Scheme Procedure} dicod-service [#:config (dicod-configuration)]
35960 Return a service that runs the @command{dicod} daemon, an implementation
35961 of DICT server (@pxref{Dicod,,, dico, GNU Dico Manual}).
35963 The optional @var{config} argument specifies the configuration for
35964 @command{dicod}, which should be a @code{<dicod-configuration>} object, by
35965 default it serves the GNU Collaborative International Dictionary of English.
35967 You can add @command{open localhost} to your @file{~/.dico} file to make
35968 @code{localhost} the default server for @command{dico} client
35969 (@pxref{Initialization File,,, dico, GNU Dico Manual}).
35972 @deftp {Data Type} dicod-configuration
35973 Data type representing the configuration of dicod.
35976 @item @code{dico} (default: @var{dico})
35977 Package object of the GNU Dico dictionary server.
35979 @item @code{interfaces} (default: @var{'("localhost")})
35980 This is the list of IP addresses and ports and possibly socket file
35981 names to listen to (@pxref{Server Settings, @code{listen} directive,,
35982 dico, GNU Dico Manual}).
35984 @item @code{handlers} (default: @var{'()})
35985 List of @code{<dicod-handler>} objects denoting handlers (module instances).
35987 @item @code{databases} (default: @var{(list %dicod-database:gcide)})
35988 List of @code{<dicod-database>} objects denoting dictionaries to be served.
35992 @deftp {Data Type} dicod-handler
35993 Data type representing a dictionary handler (module instance).
35997 Name of the handler (module instance).
35999 @item @code{module} (default: @var{#f})
36000 Name of the dicod module of the handler (instance). If it is @code{#f},
36001 the module has the same name as the handler.
36002 (@pxref{Modules,,, dico, GNU Dico Manual}).
36004 @item @code{options}
36005 List of strings or gexps representing the arguments for the module handler
36009 @deftp {Data Type} dicod-database
36010 Data type representing a dictionary database.
36014 Name of the database, will be used in DICT commands.
36016 @item @code{handler}
36017 Name of the dicod handler (module instance) used by this database
36018 (@pxref{Handlers,,, dico, GNU Dico Manual}).
36020 @item @code{complex?} (default: @var{#f})
36021 Whether the database configuration complex. The complex configuration
36022 will need a corresponding @code{<dicod-handler>} object, otherwise not.
36024 @item @code{options}
36025 List of strings or gexps representing the arguments for the database
36026 (@pxref{Databases,,, dico, GNU Dico Manual}).
36030 @defvr {Scheme Variable} %dicod-database:gcide
36031 A @code{<dicod-database>} object serving the GNU Collaborative International
36032 Dictionary of English using the @code{gcide} package.
36035 The following is an example @code{dicod-service} configuration.
36038 (dicod-service #:config
36039 (dicod-configuration
36040 (handlers (list (dicod-handler
36044 (list #~(string-append "dbdir=" #$wordnet))))))
36045 (databases (list (dicod-database
36048 (handler "wordnet")
36049 (options '("database=wn")))
36050 %dicod-database:gcide))))
36054 @subsubheading Docker Service
36056 The @code{(gnu services docker)} module provides the following services.
36058 @defvr {Scheme Variable} docker-service-type
36060 This is the type of the service that runs @url{https://www.docker.com,Docker},
36061 a daemon that can execute application bundles (sometimes referred to as
36062 ``containers'') in isolated environments.
36066 @deftp {Data Type} docker-configuration
36067 This is the data type representing the configuration of Docker and Containerd.
36071 @item @code{docker} (default: @code{docker})
36072 The Docker daemon package to use.
36074 @item @code{docker-cli} (default: @code{docker-cli})
36075 The Docker client package to use.
36077 @item @code{containerd} (default: @var{containerd})
36078 The Containerd package to use.
36080 @item @code{proxy} (default @var{docker-libnetwork-cmd-proxy})
36081 The Docker user-land networking proxy package to use.
36083 @item @code{enable-proxy?} (default @code{#t})
36084 Enable or disable the use of the Docker user-land networking proxy.
36086 @item @code{debug?} (default @code{#f})
36087 Enable or disable debug output.
36089 @item @code{enable-iptables?} (default @code{#t})
36090 Enable or disable the addition of iptables rules.
36092 @item @code{environment-variables} (default: @code{()})
36093 List of environment variables to set for @command{dockerd}.
36095 This must be a list of strings where each string has the form
36096 @samp{@var{key}=@var{value}} as in this example:
36099 (list "LANGUAGE=eo:ca:eu"
36100 "TMPDIR=/tmp/dockerd")
36106 @cindex Singularity, container service
36107 @defvr {Scheme Variable} singularity-service-type
36108 This is the type of the service that allows you to run
36109 @url{https://www.sylabs.io/singularity/, Singularity}, a Docker-style tool to
36110 create and run application bundles (aka. ``containers''). The value for this
36111 service is the Singularity package to use.
36113 The service does not install a daemon; instead, it installs helper programs as
36114 setuid-root (@pxref{Setuid Programs}) such that unprivileged users can invoke
36115 @command{singularity run} and similar commands.
36119 @subsubheading Auditd Service
36121 The @code{(gnu services auditd)} module provides the following service.
36123 @defvr {Scheme Variable} auditd-service-type
36125 This is the type of the service that runs
36126 @url{https://people.redhat.com/sgrubb/audit/,auditd},
36127 a daemon that tracks security-relevant information on your system.
36129 Examples of things that can be tracked:
36139 Failed login attempts
36146 @command{auditctl} from the @code{audit} package can be used in order
36147 to add or remove events to be tracked (until the next reboot).
36148 In order to permanently track events, put the command line arguments
36149 of auditctl into a file called @code{audit.rules} in the configuration
36150 directory (see below).
36151 @command{aureport} from the @code{audit} package can be used in order
36152 to view a report of all recorded events.
36153 The audit daemon by default logs into the file
36154 @file{/var/log/audit.log}.
36158 @deftp {Data Type} auditd-configuration
36159 This is the data type representing the configuration of auditd.
36163 @item @code{audit} (default: @code{audit})
36164 The audit package to use.
36166 @item @code{configuration-directory} (default: @code{%default-auditd-configuration-directory})
36167 The directory containing the configuration file for the audit package, which
36168 must be named @code{auditd.conf}, and optionally some audit rules to
36169 instantiate on startup.
36175 @subsubheading R-Shiny service
36177 The @code{(gnu services science)} module provides the following service.
36179 @defvr {Scheme Variable} rshiny-service-type
36181 This is a type of service which is used to run a webapp created with
36182 @code{r-shiny}. This service sets the @env{R_LIBS_USER} environment
36183 variable and runs the provided script to call @code{runApp}.
36185 @deftp {Data Type} rshiny-configuration
36186 This is the data type representing the configuration of rshiny.
36190 @item @code{package} (default: @code{r-shiny})
36191 The package to use.
36193 @item @code{binary} (defaunlt @code{"rshiny"})
36194 The name of the binary or shell script located at @code{package/bin/} to
36195 run when the service is run.
36197 The common way to create this file is as follows:
36201 (let* ((out (assoc-ref %outputs "out"))
36202 (targetdir (string-append out "/share/" ,name))
36203 (app (string-append out "/bin/" ,name))
36204 (Rbin (search-input-file %build-inputs "/bin/Rscript")))
36206 (mkdir-p (string-append out "/bin"))
36207 (call-with-output-file app
36213 runApp(launch.browser=0, port=4202)~%\n"
36222 @subsubheading Nix service
36224 The @code{(gnu services nix)} module provides the following service.
36226 @defvr {Scheme Variable} nix-service-type
36228 This is the type of the service that runs build daemon of the
36229 @url{https://nixos.org/nix/, Nix} package manager. Here is an example showing
36233 (use-modules (gnu))
36234 (use-service-modules nix)
36235 (use-package-modules package-management)
36239 (packages (append (list nix)
36242 (services (append (list (service nix-service-type))
36246 After @command{guix system reconfigure} configure Nix for your user:
36249 @item Add a Nix channel and update it. See
36250 @url{https://nixos.org/nix/manual/, Nix Package Manager Guide}.
36252 @item Create a symlink to your profile and activate Nix profile:
36256 $ ln -s "/nix/var/nix/profiles/per-user/$USER/profile" ~/.nix-profile
36257 $ source /run/current-system/profile/etc/profile.d/nix.sh
36262 @deftp {Data Type} nix-configuration
36263 This data type represents the configuration of the Nix daemon.
36266 @item @code{nix} (default: @code{nix})
36267 The Nix package to use.
36269 @item @code{sandbox} (default: @code{#t})
36270 Specifies whether builds are sandboxed by default.
36272 @item @code{build-sandbox-items} (default: @code{'()})
36273 This is a list of strings or objects appended to the
36274 @code{build-sandbox-items} field of the configuration file.
36276 @item @code{extra-config} (default: @code{'()})
36277 This is a list of strings or objects appended to the configuration file.
36278 It is used to pass extra text to be added verbatim to the configuration
36281 @item @code{extra-options} (default: @code{'()})
36282 Extra command line options for @code{nix-service-type}.
36286 @node Setuid Programs
36287 @section Setuid Programs
36289 @cindex setuid programs
36290 @cindex setgid programs
36291 Some programs need to run with elevated privileges, even when they are
36292 launched by unprivileged users. A notorious example is the
36293 @command{passwd} program, which users can run to change their
36294 password, and which needs to access the @file{/etc/passwd} and
36295 @file{/etc/shadow} files---something normally restricted to root, for
36296 obvious security reasons. To address that, @command{passwd} should be
36297 @dfn{setuid-root}, meaning that it always runs with root privileges
36298 (@pxref{How Change Persona,,, libc, The GNU C Library Reference Manual},
36299 for more info about the setuid mechanism).
36301 The store itself @emph{cannot} contain setuid programs: that would be a
36302 security issue since any user on the system can write derivations that
36303 populate the store (@pxref{The Store}). Thus, a different mechanism is
36304 used: instead of changing the setuid or setgid bits directly on files that
36305 are in the store, we let the system administrator @emph{declare} which
36306 programs should be entrusted with these additional privileges.
36308 The @code{setuid-programs} field of an @code{operating-system}
36309 declaration contains a list of @code{<setuid-program>} denoting the
36310 names of programs to have a setuid or setgid bit set (@pxref{Using the
36311 Configuration System}). For instance, the @command{mount.nfs} program,
36312 which is part of the nfs-utils package, with a setuid root can be
36313 designated like this:
36317 (program (file-append nfs-utils "/sbin/mount.nfs")))
36320 And then, to make @command{mount.nfs} setuid on your system, add the
36321 previous example to your operating system declaration by appending it to
36322 @code{%setuid-programs} like this:
36326 ;; Some fields omitted...
36328 (append (list (setuid-program
36329 (program (file-append nfs-utils "/sbin/mount.nfs"))))
36330 %setuid-programs)))
36333 @deftp {Data Type} setuid-program
36334 This data type represents a program with a setuid or setgid bit set.
36337 @item @code{program}
36338 A file-like object having its setuid and/or setgid bit set.
36340 @item @code{setuid?} (default: @code{#t})
36341 Whether to set user setuid bit.
36343 @item @code{setgid?} (default: @code{#f})
36344 Whether to set group setgid bit.
36346 @item @code{user} (default: @code{0})
36347 UID (integer) or user name (string) for the user owner of the program,
36350 @item @code{group} (default: @code{0})
36351 GID (integer) goup name (string) for the group owner of the program,
36357 A default set of setuid programs is defined by the
36358 @code{%setuid-programs} variable of the @code{(gnu system)} module.
36360 @defvr {Scheme Variable} %setuid-programs
36361 A list of @code{<setuid-program>} denoting common programs that are
36364 The list includes commands such as @command{passwd}, @command{ping},
36365 @command{su}, and @command{sudo}.
36368 Under the hood, the actual setuid programs are created in the
36369 @file{/run/setuid-programs} directory at system activation time. The
36370 files in this directory refer to the ``real'' binaries, which are in the
36373 @node X.509 Certificates
36374 @section X.509 Certificates
36376 @cindex HTTPS, certificates
36377 @cindex X.509 certificates
36379 Web servers available over HTTPS (that is, HTTP over the transport-layer
36380 security mechanism, TLS) send client programs an @dfn{X.509 certificate}
36381 that the client can then use to @emph{authenticate} the server. To do
36382 that, clients verify that the server's certificate is signed by a
36383 so-called @dfn{certificate authority} (CA). But to verify the CA's
36384 signature, clients must have first acquired the CA's certificate.
36386 Web browsers such as GNU@tie{}IceCat include their own set of CA
36387 certificates, such that they are able to verify CA signatures
36390 However, most other programs that can talk HTTPS---@command{wget},
36391 @command{git}, @command{w3m}, etc.---need to be told where CA
36392 certificates can be found.
36394 @cindex @code{nss-certs}
36395 In Guix, this is done by adding a package that provides certificates
36396 to the @code{packages} field of the @code{operating-system} declaration
36397 (@pxref{operating-system Reference}). Guix includes one such package,
36398 @code{nss-certs}, which is a set of CA certificates provided as part of
36399 Mozilla's Network Security Services.
36401 Note that it is @emph{not} part of @code{%base-packages}, so you need to
36402 explicitly add it. The @file{/etc/ssl/certs} directory, which is where
36403 most applications and libraries look for certificates by default, points
36404 to the certificates installed globally.
36406 Unprivileged users, including users of Guix on a foreign distro,
36407 can also install their own certificate package in
36408 their profile. A number of environment variables need to be defined so
36409 that applications and libraries know where to find them. Namely, the
36410 OpenSSL library honors the @env{SSL_CERT_DIR} and @env{SSL_CERT_FILE}
36411 variables. Some applications add their own environment variables; for
36412 instance, the Git version control system honors the certificate bundle
36413 pointed to by the @env{GIT_SSL_CAINFO} environment variable. Thus, you
36414 would typically run something like:
36417 guix install nss-certs
36418 export SSL_CERT_DIR="$HOME/.guix-profile/etc/ssl/certs"
36419 export SSL_CERT_FILE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
36420 export GIT_SSL_CAINFO="$SSL_CERT_FILE"
36423 As another example, R requires the @env{CURL_CA_BUNDLE} environment
36424 variable to point to a certificate bundle, so you would have to run
36425 something like this:
36428 guix install nss-certs
36429 export CURL_CA_BUNDLE="$HOME/.guix-profile/etc/ssl/certs/ca-certificates.crt"
36432 For other applications you may want to look up the required environment
36433 variable in the relevant documentation.
36436 @node Name Service Switch
36437 @section Name Service Switch
36439 @cindex name service switch
36441 The @code{(gnu system nss)} module provides bindings to the
36442 configuration file of the libc @dfn{name service switch} or @dfn{NSS}
36443 (@pxref{NSS Configuration File,,, libc, The GNU C Library Reference
36444 Manual}). In a nutshell, the NSS is a mechanism that allows libc to be
36445 extended with new ``name'' lookup methods for system databases, which
36446 includes host names, service names, user accounts, and more (@pxref{Name
36447 Service Switch, System Databases and Name Service Switch,, libc, The GNU
36448 C Library Reference Manual}).
36450 The NSS configuration specifies, for each system database, which lookup
36451 method is to be used, and how the various methods are chained
36452 together---for instance, under which circumstances NSS should try the
36453 next method in the list. The NSS configuration is given in the
36454 @code{name-service-switch} field of @code{operating-system} declarations
36455 (@pxref{operating-system Reference, @code{name-service-switch}}).
36458 @cindex .local, host name lookup
36459 As an example, the declaration below configures the NSS to use the
36460 @uref{https://0pointer.de/lennart/projects/nss-mdns/, @code{nss-mdns}
36461 back-end}, which supports host name lookups over multicast DNS (mDNS)
36462 for host names ending in @code{.local}:
36465 (name-service-switch
36466 (hosts (list %files ;first, check /etc/hosts
36468 ;; If the above did not succeed, try
36469 ;; with 'mdns_minimal'.
36471 (name "mdns_minimal")
36473 ;; 'mdns_minimal' is authoritative for
36474 ;; '.local'. When it returns "not found",
36475 ;; no need to try the next methods.
36476 (reaction (lookup-specification
36477 (not-found => return))))
36479 ;; Then fall back to DNS.
36483 ;; Finally, try with the "full" 'mdns'.
36488 Do not worry: the @code{%mdns-host-lookup-nss} variable (see below)
36489 contains this configuration, so you will not have to type it if all you
36490 want is to have @code{.local} host lookup working.
36492 Note that, in this case, in addition to setting the
36493 @code{name-service-switch} of the @code{operating-system} declaration,
36494 you also need to use @code{avahi-service-type} (@pxref{Networking Services,
36495 @code{avahi-service-type}}), or @code{%desktop-services}, which includes it
36496 (@pxref{Desktop Services}). Doing this makes @code{nss-mdns} accessible
36497 to the name service cache daemon (@pxref{Base Services,
36498 @code{nscd-service}}).
36500 For convenience, the following variables provide typical NSS
36503 @defvr {Scheme Variable} %default-nss
36504 This is the default name service switch configuration, a
36505 @code{name-service-switch} object.
36508 @defvr {Scheme Variable} %mdns-host-lookup-nss
36509 This is the name service switch configuration with support for host name
36510 lookup over multicast DNS (mDNS) for host names ending in @code{.local}.
36513 The reference for name service switch configuration is given below. It
36514 is a direct mapping of the configuration file format of the C library , so
36515 please refer to the C library manual for more information (@pxref{NSS
36516 Configuration File,,, libc, The GNU C Library Reference Manual}).
36517 Compared to the configuration file format of libc NSS, it has the advantage
36518 not only of adding this warm parenthetic feel that we like, but also
36519 static checks: you will know about syntax errors and typos as soon as you
36520 run @command{guix system}.
36522 @deftp {Data Type} name-service-switch
36524 This is the data type representation the configuration of libc's name
36525 service switch (NSS). Each field below represents one of the supported
36542 The system databases handled by the NSS@. Each of these fields must be a
36543 list of @code{<name-service>} objects (see below).
36547 @deftp {Data Type} name-service
36549 This is the data type representing an actual name service and the
36550 associated lookup action.
36554 A string denoting the name service (@pxref{Services in the NSS
36555 configuration,,, libc, The GNU C Library Reference Manual}).
36557 Note that name services listed here must be visible to nscd. This is
36558 achieved by passing the @code{#:name-services} argument to
36559 @code{nscd-service} the list of packages providing the needed name
36560 services (@pxref{Base Services, @code{nscd-service}}).
36563 An action specified using the @code{lookup-specification} macro
36564 (@pxref{Actions in the NSS configuration,,, libc, The GNU C Library
36565 Reference Manual}). For example:
36568 (lookup-specification (unavailable => continue)
36569 (success => return))
36574 @node Initial RAM Disk
36575 @section Initial RAM Disk
36578 @cindex initial RAM disk
36579 For bootstrapping purposes, the Linux-Libre kernel is passed an
36580 @dfn{initial RAM disk}, or @dfn{initrd}. An initrd contains a temporary
36581 root file system as well as an initialization script. The latter is
36582 responsible for mounting the real root file system, and for loading any
36583 kernel modules that may be needed to achieve that.
36585 The @code{initrd-modules} field of an @code{operating-system}
36586 declaration allows you to specify Linux-libre kernel modules that must
36587 be available in the initrd. In particular, this is where you would list
36588 modules needed to actually drive the hard disk where your root partition
36589 is---although the default value of @code{initrd-modules} should cover
36590 most use cases. For example, assuming you need the @code{megaraid_sas}
36591 module in addition to the default modules to be able to access your root
36592 file system, you would write:
36597 (initrd-modules (cons "megaraid_sas" %base-initrd-modules)))
36600 @defvr {Scheme Variable} %base-initrd-modules
36601 This is the list of kernel modules included in the initrd by default.
36604 Furthermore, if you need lower-level customization, the @code{initrd}
36605 field of an @code{operating-system} declaration allows
36606 you to specify which initrd you would like to use. The @code{(gnu
36607 system linux-initrd)} module provides three ways to build an initrd: the
36608 high-level @code{base-initrd} procedure and the low-level
36609 @code{raw-initrd} and @code{expression->initrd} procedures.
36611 The @code{base-initrd} procedure is intended to cover most common uses.
36612 For example, if you want to add a bunch of kernel modules to be loaded
36613 at boot time, you can define the @code{initrd} field of the operating
36614 system declaration like this:
36617 (initrd (lambda (file-systems . rest)
36618 ;; Create a standard initrd but set up networking
36619 ;; with the parameters QEMU expects by default.
36620 (apply base-initrd file-systems
36621 #:qemu-networking? #t
36625 The @code{base-initrd} procedure also handles common use cases that
36626 involves using the system as a QEMU guest, or as a ``live'' system with
36627 volatile root file system.
36629 The @code{base-initrd} procedure is built from @code{raw-initrd} procedure.
36630 Unlike @code{base-initrd}, @code{raw-initrd} doesn't do anything high-level,
36631 such as trying to guess which kernel modules and packages should be included
36632 to the initrd. An example use of @code{raw-initrd} is when a user has
36633 a custom Linux kernel configuration and default kernel modules included by
36634 @code{base-initrd} are not available.
36636 The initial RAM disk produced by @code{base-initrd} or @code{raw-initrd}
36637 honors several options passed on the Linux kernel command line
36638 (that is, arguments passed @i{via} the @code{linux} command of GRUB, or the
36639 @code{-append} option of QEMU), notably:
36642 @item gnu.load=@var{boot}
36643 Tell the initial RAM disk to load @var{boot}, a file containing a Scheme
36644 program, once it has mounted the root file system.
36646 Guix uses this option to yield control to a boot program that runs the
36647 service activation programs and then spawns the GNU@tie{}Shepherd, the
36648 initialization system.
36650 @item root=@var{root}
36651 Mount @var{root} as the root file system. @var{root} can be a device
36652 name like @code{/dev/sda1}, a file system label, or a file system UUID.
36653 When unspecified, the device name from the root file system of the
36654 operating system declaration is used.
36656 @item rootfstype=@var{type}
36657 Set the type of the root file system. It overrides the @code{type}
36658 field of the root file system specified via the @code{operating-system}
36659 declaration, if any.
36661 @item rootflags=@var{options}
36662 Set the mount @emph{options} of the root file system. It overrides the
36663 @code{options} field of the root file system specified via the
36664 @code{operating-system} declaration, if any.
36666 @item fsck.mode=@var{mode}
36667 Whether to check the @var{root} file system for errors before mounting
36668 it. @var{mode} is one of @code{skip} (never check), @code{force} (always
36669 check), or @code{auto} to respect the root file-system object's 'check?'
36670 setting (@pxref{File Systems}) and run a full scan only if the file system
36671 was not cleanly shut down.
36673 @code{auto} is the default if this option is not present or if @var{mode}
36674 is not one of the above.
36676 @item fsck.repair=@var{level}
36677 The level of repairs to perform automatically if errors are found in the
36678 @var{root} file system. @var{level} is one of @code{no} (do not write to
36679 @var{root} at all if possible), @code{yes} (repair as much as possible),
36680 or @code{preen} to repair problems considered safe to repair automatically.
36682 @code{preen} is the default if this option is not present or if @var{level}
36683 is not one of the above.
36685 @item gnu.system=@var{system}
36686 Have @file{/run/booted-system} and @file{/run/current-system} point to
36689 @item modprobe.blacklist=@var{modules}@dots{}
36690 @cindex module, black-listing
36691 @cindex black list, of kernel modules
36692 Instruct the initial RAM disk as well as the @command{modprobe} command
36693 (from the kmod package) to refuse to load @var{modules}. @var{modules}
36694 must be a comma-separated list of module names---e.g.,
36695 @code{usbkbd,9pnet}.
36698 Start a read-eval-print loop (REPL) from the initial RAM disk before it
36699 tries to load kernel modules and to mount the root file system. Our
36700 marketing team calls it @dfn{boot-to-Guile}. The Schemer in you will
36701 love it. @xref{Using Guile Interactively,,, guile, GNU Guile Reference
36702 Manual}, for more information on Guile's REPL.
36706 Now that you know all the features that initial RAM disks produced by
36707 @code{base-initrd} and @code{raw-initrd} provide,
36708 here is how to use it and customize it further.
36711 @cindex initial RAM disk
36712 @deffn {Scheme Procedure} raw-initrd @var{file-systems} @
36713 [#:linux-modules '()] [#:mapped-devices '()] @
36714 [#:keyboard-layout #f] @
36715 [#:helper-packages '()] [#:qemu-networking? #f] [#:volatile-root? #f]
36716 Return a derivation that builds a raw initrd. @var{file-systems} is
36717 a list of file systems to be mounted by the initrd, possibly in addition to
36718 the root file system specified on the kernel command line via @option{root}.
36719 @var{linux-modules} is a list of kernel modules to be loaded at boot time.
36720 @var{mapped-devices} is a list of device mappings to realize before
36721 @var{file-systems} are mounted (@pxref{Mapped Devices}).
36722 @var{helper-packages} is a list of packages to be copied in the initrd.
36724 include @code{e2fsck/static} or other packages needed by the initrd to check
36725 the root file system.
36727 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
36728 the desired console keyboard layout. This is done before @var{mapped-devices}
36729 are set up and before @var{file-systems} are mounted such that, should the
36730 user need to enter a passphrase or use the REPL, this happens using the
36731 intended keyboard layout.
36733 When @var{qemu-networking?} is true, set up networking with the standard QEMU
36734 parameters. When @var{virtio?} is true, load additional modules so that the
36735 initrd can be used as a QEMU guest with para-virtualized I/O drivers.
36737 When @var{volatile-root?} is true, the root file system is writable but any changes
36741 @deffn {Scheme Procedure} base-initrd @var{file-systems} @
36742 [#:mapped-devices '()] [#:keyboard-layout #f] @
36743 [#:qemu-networking? #f] [#:volatile-root? #f] @
36744 [#:linux-modules '()]
36745 Return as a file-like object a generic initrd, with kernel
36746 modules taken from @var{linux}. @var{file-systems} is a list of file-systems to be
36747 mounted by the initrd, possibly in addition to the root file system specified
36748 on the kernel command line via @option{root}. @var{mapped-devices} is a list of device
36749 mappings to realize before @var{file-systems} are mounted.
36751 When true, @var{keyboard-layout} is a @code{<keyboard-layout>} record denoting
36752 the desired console keyboard layout. This is done before @var{mapped-devices}
36753 are set up and before @var{file-systems} are mounted such that, should the
36754 user need to enter a passphrase or use the REPL, this happens using the
36755 intended keyboard layout.
36757 @var{qemu-networking?} and @var{volatile-root?} behaves as in @code{raw-initrd}.
36759 The initrd is automatically populated with all the kernel modules necessary
36760 for @var{file-systems} and for the given options. Additional kernel
36761 modules can be listed in @var{linux-modules}. They will be added to the initrd, and
36762 loaded at boot time in the order in which they appear.
36765 Needless to say, the initrds we produce and use embed a
36766 statically-linked Guile, and the initialization program is a Guile
36767 program. That gives a lot of flexibility. The
36768 @code{expression->initrd} procedure builds such an initrd, given the
36769 program to run in that initrd.
36771 @deffn {Scheme Procedure} expression->initrd @var{exp} @
36772 [#:guile %guile-static-stripped] [#:name "guile-initrd"]
36773 Return as a file-like object a Linux initrd (a gzipped cpio archive)
36774 containing @var{guile} and that evaluates @var{exp}, a G-expression,
36775 upon booting. All the derivations referenced by @var{exp} are
36776 automatically copied to the initrd.
36779 @node Bootloader Configuration
36780 @section Bootloader Configuration
36783 @cindex boot loader
36785 The operating system supports multiple bootloaders. The bootloader is
36786 configured using @code{bootloader-configuration} declaration. All the
36787 fields of this structure are bootloader agnostic except for one field,
36788 @code{bootloader} that indicates the bootloader to be configured and
36791 Some of the bootloaders do not honor every field of
36792 @code{bootloader-configuration}. For instance, the extlinux
36793 bootloader does not support themes and thus ignores the @code{theme}
36796 @deftp {Data Type} bootloader-configuration
36797 The type of a bootloader configuration declaration.
36801 @item @code{bootloader}
36802 @cindex EFI, bootloader
36803 @cindex UEFI, bootloader
36804 @cindex BIOS, bootloader
36805 The bootloader to use, as a @code{bootloader} object. For now
36806 @code{grub-bootloader}, @code{grub-efi-bootloader},
36807 @code{grub-efi-netboot-bootloader}, @code{grub-efi-removable-bootloader},
36808 @code{extlinux-bootloader} and @code{u-boot-bootloader} are supported.
36810 @cindex ARM, bootloaders
36811 @cindex AArch64, bootloaders
36812 Available bootloaders are described in @code{(gnu bootloader @dots{})}
36813 modules. In particular, @code{(gnu bootloader u-boot)} contains definitions
36814 of bootloaders for a wide range of ARM and AArch64 systems, using the
36815 @uref{https://www.denx.de/wiki/U-Boot/, U-Boot bootloader}.
36817 @vindex grub-efi-bootloader
36818 @code{grub-efi-bootloader} allows to boot on modern systems using the
36819 @dfn{Unified Extensible Firmware Interface} (UEFI). This is what you should
36820 use if the installation image contains a @file{/sys/firmware/efi} directory
36821 when you boot it on your system.
36823 @vindex grub-bootloader
36824 @code{grub-bootloader} allows you to boot in particular Intel-based machines
36825 in ``legacy'' BIOS mode.
36827 @vindex grub-efi-netboot-bootloader
36828 @code{grub-efi-netboot-bootloader} allows you to boot your system over network
36829 through TFTP@. In combination with an NFS root file system this allows you to
36830 build a diskless Guix system.
36832 The installation of the @code{grub-efi-netboot-bootloader} generates the
36833 content of the TFTP root directory at @code{targets} (@pxref{Bootloader
36834 Configuration, @code{targets}}), to be served by a TFTP server. You may
36835 want to mount your TFTP server directories onto the @code{targets} to
36836 move the required files to the TFTP server automatically.
36838 If you plan to use an NFS root file system as well (actually if you mount the
36839 store from an NFS share), then the TFTP server needs to serve the file
36840 @file{/boot/grub/grub.cfg} and other files from the store (like GRUBs background
36841 image, the kernel (@pxref{operating-system Reference, @code{kernel}}) and the
36842 initrd (@pxref{operating-system Reference, @code{initrd}})), too. All these
36843 files from the store will be accessed by GRUB through TFTP with their normal
36844 store path, for example as
36845 @file{tftp://tftp-server/gnu/store/…-initrd/initrd.cpio.gz}.
36847 Two symlinks are created to make this possible. For each target in the
36848 @code{targets} field, the first symlink is
36849 @samp{target}@file{/efi/Guix/boot/grub/grub.cfg} pointing to
36850 @file{../../../boot/grub/grub.cfg}, where @samp{target} may be
36851 @file{/boot}. In this case the link is not leaving the served TFTP root
36852 directory, but otherwise it does. The second link is
36853 @samp{target}@file{/gnu/store} and points to @file{../gnu/store}. This
36854 link is leaving the served TFTP root directory.
36856 The assumption behind all this is that you have an NFS server exporting
36857 the root file system for your Guix system, and additionally a TFTP
36858 server exporting your @code{targets} directories—usually a single
36859 @file{/boot}—from that same root file system for your Guix system. In
36860 this constellation the symlinks will work.
36862 For other constellations you will have to program your own bootloader
36863 installer, which then takes care to make necessary files from the store
36864 accessible through TFTP, for example by copying them into the TFTP root
36865 directory to your @code{targets}.
36867 It is important to note that symlinks pointing outside the TFTP root directory
36868 may need to be allowed in the configuration of your TFTP server. Further the
36869 store link exposes the whole store through TFTP@. Both points need to be
36870 considered carefully for security aspects.
36872 Beside the @code{grub-efi-netboot-bootloader}, the already mentioned TFTP and
36873 NFS servers, you also need a properly configured DHCP server to make the booting
36874 over netboot possible. For all this we can currently only recommend you to look
36875 for instructions about @acronym{PXE, Preboot eXecution Environment}.
36877 @vindex grub-efi-removable-bootloader
36878 @code{grub-efi-removable-bootloader} allows you to boot your system from
36879 removable media by writing the GRUB file to the UEFI-specification location of
36880 @file{/EFI/BOOT/BOOTX64.efi} of the boot directory, usually @file{/boot/efi}.
36881 This is also useful for some UEFI firmwares that ``forget'' their configuration
36882 from their non-volatile storage. Like @code{grub-efi-bootloader}, this can only
36883 be used if the @file{/sys/firmware/efi} directory is available.
36886 This @emph{will} overwrite the GRUB file from any other operating systems that
36887 also place their GRUB file in the UEFI-specification location; making them
36891 @item @code{targets}
36892 This is a list of strings denoting the targets onto which to install the
36895 The interpretation of targets depends on the bootloader in question.
36896 For @code{grub-bootloader}, for example, they should be device names
36897 understood by the bootloader @command{installer} command, such as
36898 @code{/dev/sda} or @code{(hd0)} (@pxref{Invoking grub-install,,, grub,
36899 GNU GRUB Manual}). For @code{grub-efi-bootloader} and
36900 @code{grub-efi-removable-bootloader} they should be mount
36901 points of the EFI file system, usually @file{/boot/efi}. For
36902 @code{grub-efi-netboot-bootloader}, @code{targets} should be the mount
36903 points corresponding to TFTP root directories served by your TFTP
36906 @item @code{menu-entries} (default: @code{()})
36907 A possibly empty list of @code{menu-entry} objects (see below), denoting
36908 entries to appear in the bootloader menu, in addition to the current
36909 system entry and the entry pointing to previous system generations.
36911 @item @code{default-entry} (default: @code{0})
36912 The index of the default boot menu entry. Index 0 is for the entry of the
36915 @item @code{timeout} (default: @code{5})
36916 The number of seconds to wait for keyboard input before booting. Set to
36917 0 to boot immediately, and to -1 to wait indefinitely.
36919 @cindex keyboard layout, for the bootloader
36920 @item @code{keyboard-layout} (default: @code{#f})
36921 If this is @code{#f}, the bootloader's menu (if any) uses the default keyboard
36922 layout, usually US@tie{}English (``qwerty'').
36924 Otherwise, this must be a @code{keyboard-layout} object (@pxref{Keyboard
36928 This option is currently ignored by bootloaders other than @code{grub} and
36932 @item @code{theme} (default: @var{#f})
36933 The bootloader theme object describing the theme to use. If no theme
36934 is provided, some bootloaders might use a default theme, that's true
36937 @item @code{terminal-outputs} (default: @code{'(gfxterm)})
36938 The output terminals used for the bootloader boot menu, as a list of
36939 symbols. GRUB accepts the values: @code{console}, @code{serial},
36940 @code{serial_@{0-3@}}, @code{gfxterm}, @code{vga_text},
36941 @code{mda_text}, @code{morse}, and @code{pkmodem}. This field
36942 corresponds to the GRUB variable @code{GRUB_TERMINAL_OUTPUT} (@pxref{Simple
36943 configuration,,, grub,GNU GRUB manual}).
36945 @item @code{terminal-inputs} (default: @code{'()})
36946 The input terminals used for the bootloader boot menu, as a list of
36947 symbols. For GRUB, the default is the native platform terminal as
36948 determined at run-time. GRUB accepts the values: @code{console},
36949 @code{serial}, @code{serial_@{0-3@}}, @code{at_keyboard}, and
36950 @code{usb_keyboard}. This field corresponds to the GRUB variable
36951 @code{GRUB_TERMINAL_INPUT} (@pxref{Simple configuration,,, grub,GNU GRUB
36954 @item @code{serial-unit} (default: @code{#f})
36955 The serial unit used by the bootloader, as an integer from 0 to 3.
36956 For GRUB, it is chosen at run-time; currently GRUB chooses 0, which
36957 corresponds to COM1 (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
36959 @item @code{serial-speed} (default: @code{#f})
36960 The speed of the serial interface, as an integer. For GRUB, the
36961 default value is chosen at run-time; currently GRUB chooses
36962 9600@tie{}bps (@pxref{Serial terminal,,, grub,GNU GRUB manual}).
36969 Should you want to list additional boot menu entries @i{via} the
36970 @code{menu-entries} field above, you will need to create them with the
36971 @code{menu-entry} form. For example, imagine you want to be able to
36972 boot another distro (hard to imagine!), you can define a menu entry
36977 (label "The Other Distro")
36978 (linux "/boot/old/vmlinux-2.6.32")
36979 (linux-arguments '("root=/dev/sda2"))
36980 (initrd "/boot/old/initrd"))
36985 @deftp {Data Type} menu-entry
36986 The type of an entry in the bootloader menu.
36991 The label to show in the menu---e.g., @code{"GNU"}.
36993 @item @code{linux} (default: @code{#f})
36994 The Linux kernel image to boot, for example:
36997 (file-append linux-libre "/bzImage")
37000 For GRUB, it is also possible to specify a device explicitly in the
37001 file path using GRUB's device naming convention (@pxref{Naming
37002 convention,,, grub, GNU GRUB manual}), for example:
37005 "(hd0,msdos1)/boot/vmlinuz"
37008 If the device is specified explicitly as above, then the @code{device}
37009 field is ignored entirely.
37011 @item @code{linux-arguments} (default: @code{()})
37012 The list of extra Linux kernel command-line arguments---e.g.,
37013 @code{("console=ttyS0")}.
37015 @item @code{initrd} (default: @code{#f})
37016 A G-Expression or string denoting the file name of the initial RAM disk
37017 to use (@pxref{G-Expressions}).
37019 @item @code{device} (default: @code{#f})
37020 The device where the kernel and initrd are to be found---i.e., for GRUB,
37021 @dfn{root} for this menu entry (@pxref{root,,, grub, GNU GRUB manual}).
37023 This may be a file system label (a string), a file system UUID (a
37024 bytevector, @pxref{File Systems}), or @code{#f}, in which case
37025 the bootloader will search the device containing the file specified by
37026 the @code{linux} field (@pxref{search,,, grub, GNU GRUB manual}). It
37027 must @emph{not} be an OS device name such as @file{/dev/sda1}.
37029 @item @code{multiboot-kernel} (default: @code{#f})
37030 The kernel to boot in Multiboot-mode (@pxref{multiboot,,, grub, GNU GRUB
37031 manual}). When this field is set, a Multiboot menu-entry is generated.
37035 (file-append mach "/boot/gnumach")
37038 @item @code{multiboot-arguments} (default: @code{()})
37039 The list of extra command-line arguments for the multiboot-kernel.
37041 @item @code{multiboot-modules} (default: @code{()})
37042 The list of commands for loading Multiboot modules. For example:
37045 (list (list (file-append hurd "/hurd/ext2fs.static") "ext2fs"
37047 (list (file-append libc "/lib/ld.so.1") "exec"
37057 @c FIXME: Write documentation once it's stable.
37058 For now only GRUB has theme support. GRUB themes are created using
37059 the @code{grub-theme} form, which is not fully documented yet.
37061 @deftp {Data Type} grub-theme
37062 Data type representing the configuration of the GRUB theme.
37065 @item @code{gfxmode} (default: @code{'("auto")})
37066 The GRUB @code{gfxmode} to set (a list of screen resolution strings,
37067 @pxref{gfxmode,,, grub, GNU GRUB manual}).
37071 @deffn {Scheme Procedure} grub-theme
37072 Return the default GRUB theme used by the operating system if no
37073 @code{theme} field is specified in @code{bootloader-configuration}
37076 It comes with a fancy background image displaying the GNU and Guix
37080 For example, to override the default resolution, you may use something
37085 (bootloader-configuration
37088 (inherit (grub-theme))
37089 (gfxmode '("1024x786x32" "auto"))))))
37092 @node Invoking guix system
37093 @section Invoking @code{guix system}
37095 Once you have written an operating system declaration as seen in the
37096 previous section, it can be @dfn{instantiated} using the @command{guix
37097 system} command. The synopsis is:
37100 guix system @var{options}@dots{} @var{action} @var{file}
37103 @var{file} must be the name of a file containing an
37104 @code{operating-system} declaration. @var{action} specifies how the
37105 operating system is instantiated. Currently the following values are
37110 Display available service type definitions that match the given regular
37111 expressions, sorted by relevance:
37117 $ guix system search console
37118 name: console-fonts
37119 location: gnu/services/base.scm:806:2
37120 extends: shepherd-root
37121 description: Install the given fonts on the specified ttys (fonts are per
37122 + virtual console on GNU/Linux). The value of this service is a list of
37123 + tty/font pairs. The font can be the name of a font provided by the `kbd'
37124 + package or any valid argument to `setfont', as in this example:
37126 + '(("tty1" . "LatGrkCyr-8x16")
37127 + ("tty2" . (file-append
37129 + "/share/kbd/consolefonts/TamzenForPowerline10x20.psf"))
37130 + ("tty3" . (file-append
37132 + "/share/consolefonts/ter-132n"))) ; for HDPI
37136 location: gnu/services/base.scm:1190:2
37137 extends: shepherd-root
37138 description: Provide console login using the `mingetty' program.
37142 location: gnu/services/base.scm:860:2
37144 description: Provide a console log-in service as specified by its
37145 + configuration value, a `login-configuration' object.
37151 As for @command{guix package --search}, the result is written in
37152 @code{recutils} format, which makes it easy to filter the output
37153 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
37155 @cindex service type definition, editing
37156 @cindex editing, service type definition
37158 Edit or view the definition of the given service types.
37160 For example, the command below opens your editor, as specified by the
37161 @env{EDITOR} environment variable, on the definition of the
37162 @code{openssh} service type:
37165 guix system edit openssh
37169 Build the operating system described in @var{file}, activate it, and
37170 switch to it@footnote{This action (and the related actions
37171 @code{switch-generation} and @code{roll-back}) are usable only on
37172 systems already running Guix System.}.
37175 @c The paragraph below refers to the problem discussed at
37176 @c <https://lists.gnu.org/archive/html/guix-devel/2014-08/msg00057.html>.
37177 It is highly recommended to run @command{guix pull} once before you run
37178 @command{guix system reconfigure} for the first time (@pxref{Invoking
37179 guix pull}). Failing to do that you would see an older version of Guix
37180 once @command{reconfigure} has completed.
37183 This effects all the configuration specified in @var{file}: user
37184 accounts, system services, global package list, setuid programs, etc.
37185 The command starts system services specified in @var{file} that are not
37186 currently running; if a service is currently running this command will
37187 arrange for it to be upgraded the next time it is stopped (e.g.@: by
37188 @code{herd stop X} or @code{herd restart X}).
37190 This command creates a new generation whose number is one greater than
37191 the current generation (as reported by @command{guix system
37192 list-generations}). If that generation already exists, it will be
37193 overwritten. This behavior mirrors that of @command{guix package}
37194 (@pxref{Invoking guix package}).
37196 It also adds a bootloader menu entry for the new OS configuration,
37197 ---unless @option{--no-bootloader} is passed. For GRUB, it moves
37198 entries for older configurations to a submenu, allowing you to choose
37199 an older system generation at boot time should you need it.
37201 @cindex provenance tracking, of the operating system
37202 Upon completion, the new system is deployed under
37203 @file{/run/current-system}. This directory contains @dfn{provenance
37204 meta-data}: the list of channels in use (@pxref{Channels}) and
37205 @var{file} itself, when available. You can view it by running:
37208 guix system describe
37211 This information is useful should you later want to inspect how this
37212 particular generation was built. In fact, assuming @var{file} is
37213 self-contained, you can later rebuild generation @var{n} of your
37214 operating system with:
37217 guix time-machine \
37218 -C /var/guix/profiles/system-@var{n}-link/channels.scm -- \
37219 system reconfigure \
37220 /var/guix/profiles/system-@var{n}-link/configuration.scm
37223 You can think of it as some sort of built-in version control! Your
37224 system is not just a binary artifact: @emph{it carries its own source}.
37225 @xref{Service Reference, @code{provenance-service-type}}, for more
37226 information on provenance tracking.
37228 By default, @command{reconfigure} @emph{prevents you from downgrading
37229 your system}, which could (re)introduce security vulnerabilities and
37230 also cause problems with ``stateful'' services such as database
37231 management systems. You can override that behavior by passing
37232 @option{--allow-downgrades}.
37234 @item switch-generation
37235 @cindex generations
37236 Switch to an existing system generation. This action atomically
37237 switches the system profile to the specified system generation. It
37238 also rearranges the system's existing bootloader menu entries. It
37239 makes the menu entry for the specified system generation the default,
37240 and it moves the entries for the other generations to a submenu, if
37241 supported by the bootloader being used. The next time the system
37242 boots, it will use the specified system generation.
37244 The bootloader itself is not being reinstalled when using this
37245 command. Thus, the installed bootloader is used with an updated
37246 configuration file.
37248 The target generation can be specified explicitly by its generation
37249 number. For example, the following invocation would switch to system
37253 guix system switch-generation 7
37256 The target generation can also be specified relative to the current
37257 generation with the form @code{+N} or @code{-N}, where @code{+3} means
37258 ``3 generations ahead of the current generation,'' and @code{-1} means
37259 ``1 generation prior to the current generation.'' When specifying a
37260 negative value such as @code{-1}, you must precede it with @code{--} to
37261 prevent it from being parsed as an option. For example:
37264 guix system switch-generation -- -1
37267 Currently, the effect of invoking this action is @emph{only} to switch
37268 the system profile to an existing generation and rearrange the
37269 bootloader menu entries. To actually start using the target system
37270 generation, you must reboot after running this action. In the future,
37271 it will be updated to do the same things as @command{reconfigure},
37272 like activating and deactivating services.
37274 This action will fail if the specified generation does not exist.
37277 @cindex rolling back
37278 Switch to the preceding system generation. The next time the system
37279 boots, it will use the preceding system generation. This is the inverse
37280 of @command{reconfigure}, and it is exactly the same as invoking
37281 @command{switch-generation} with an argument of @code{-1}.
37283 Currently, as with @command{switch-generation}, you must reboot after
37284 running this action to actually start using the preceding system
37287 @item delete-generations
37288 @cindex deleting system generations
37289 @cindex saving space
37290 Delete system generations, making them candidates for garbage collection
37291 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
37294 This works in the same way as @samp{guix package --delete-generations}
37295 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
37296 arguments, all system generations but the current one are deleted:
37299 guix system delete-generations
37302 You can also select the generations you want to delete. The example below
37303 deletes all the system generations that are more than two months old:
37306 guix system delete-generations 2m
37309 Running this command automatically reinstalls the bootloader with an updated
37310 list of menu entries---e.g., the ``old generations'' sub-menu in GRUB no
37311 longer lists the generations that have been deleted.
37314 Build the derivation of the operating system, which includes all the
37315 configuration files and programs needed to boot and run the system.
37316 This action does not actually install anything.
37319 Populate the given directory with all the files necessary to run the
37320 operating system specified in @var{file}. This is useful for first-time
37321 installations of Guix System. For instance:
37324 guix system init my-os-config.scm /mnt
37327 copies to @file{/mnt} all the store items required by the configuration
37328 specified in @file{my-os-config.scm}. This includes configuration
37329 files, packages, and so on. It also creates other essential files
37330 needed for the system to operate correctly---e.g., the @file{/etc},
37331 @file{/var}, and @file{/run} directories, and the @file{/bin/sh} file.
37333 This command also installs bootloader on the targets specified in
37334 @file{my-os-config}, unless the @option{--no-bootloader} option was
37338 @cindex virtual machine
37340 @anchor{guix system vm}
37341 Build a virtual machine (VM) that contains the operating system declared
37342 in @var{file}, and return a script to run that VM.
37345 The @code{vm} action and others below
37346 can use KVM support in the Linux-libre kernel. Specifically, if the
37347 machine has hardware virtualization support, the corresponding
37348 KVM kernel module should be loaded, and the @file{/dev/kvm} device node
37349 must exist and be readable and writable by the user and by the
37350 build users of the daemon (@pxref{Build Environment Setup}).
37353 Arguments given to the script are passed to QEMU as in the example
37354 below, which enables networking and requests 1@tie{}GiB of RAM for the
37358 $ /gnu/store/@dots{}-run-vm.sh -m 1024 -smp 2 -nic user,model=virtio-net-pci
37361 It's possible to combine the two steps into one:
37364 $ $(guix system vm my-config.scm) -m 1024 -smp 2 -nic user,model=virtio-net-pci
37367 The VM shares its store with the host system.
37369 By default, the root file system of the VM is mounted volatile; the
37370 @option{--persistent} option can be provided to make it persistent
37371 instead. In that case, the VM disk-image file will be copied from the
37372 store to the @env{TMPDIR} directory to make it writable.
37374 Additional file systems can be shared between the host and the VM using
37375 the @option{--share} and @option{--expose} command-line options: the former
37376 specifies a directory to be shared with write access, while the latter
37377 provides read-only access to the shared directory.
37379 The example below creates a VM in which the user's home directory is
37380 accessible read-only, and where the @file{/exchange} directory is a
37381 read-write mapping of @file{$HOME/tmp} on the host:
37384 guix system vm my-config.scm \
37385 --expose=$HOME --share=$HOME/tmp=/exchange
37388 On GNU/Linux, the default is to boot directly to the kernel; this has
37389 the advantage of requiring only a very tiny root disk image since the
37390 store of the host can then be mounted.
37392 The @option{--full-boot} option forces a complete boot sequence, starting
37393 with the bootloader. This requires more disk space since a root image
37394 containing at least the kernel, initrd, and bootloader data files must
37397 The @option{--image-size} option can be used to specify the size of the
37400 The @option{--no-graphic} option will instruct @command{guix system} to
37401 spawn a headless VM that will use the invoking tty for IO. Among other
37402 things, this enables copy-pasting, and scrollback. Use the @kbd{ctrl-a}
37403 prefix to issue QEMU commands; e.g. @kbd{ctrl-a h} prints a help,
37404 @kbd{ctrl-a x} quits the VM, and @kbd{ctrl-a c} switches between the
37405 QEMU monitor and the VM.
37407 @cindex System images, creation in various formats
37408 @cindex Creating system images in various formats
37410 @cindex image, creating disk images
37411 The @code{image} command can produce various image types. The image
37412 type can be selected using the @option{--image-type} option. It
37413 defaults to @code{efi-raw}. When its value is @code{iso9660}, the
37414 @option{--label} option can be used to specify a volume ID with
37415 @code{image}. By default, the root file system of a disk image is
37416 mounted non-volatile; the @option{--volatile} option can be provided to
37417 make it volatile instead. When using @code{image}, the bootloader
37418 installed on the generated image is taken from the provided
37419 @code{operating-system} definition. The following example demonstrates
37420 how to generate an image that uses the @code{grub-efi-bootloader}
37421 bootloader and boot it with QEMU:
37424 image=$(guix system image --image-type=qcow2 \
37425 gnu/system/examples/lightweight-desktop.tmpl)
37426 cp $image /tmp/my-image.qcow2
37427 chmod +w /tmp/my-image.qcow2
37428 qemu-system-x86_64 -enable-kvm -hda /tmp/my-image.qcow2 -m 1000 \
37429 -bios $(guix build ovmf)/share/firmware/ovmf_x64.bin
37432 When using the @code{efi-raw} image type, a raw disk image is produced;
37433 it can be copied as is to a USB stick, for instance. Assuming
37434 @code{/dev/sdc} is the device corresponding to a USB stick, one can copy
37435 the image to it using the following command:
37438 # dd if=$(guix system image my-os.scm) of=/dev/sdc status=progress
37441 The @code{--list-image-types} command lists all the available image
37444 @cindex creating virtual machine images
37445 When using the @code{qcow2} image type, the returned image is in qcow2
37446 format, which the QEMU emulator can efficiently use. @xref{Running Guix
37447 in a VM}, for more information on how to run the image in a virtual
37448 machine. The @code{grub-bootloader} bootloader is always used
37449 independently of what is declared in the @code{operating-system} file
37450 passed as argument. This is to make it easier to work with QEMU, which
37451 uses the SeaBIOS BIOS by default, expecting a bootloader to be installed
37452 in the Master Boot Record (MBR).
37454 @cindex docker-image, creating docker images
37455 When using the @code{docker} image type, a Docker image is produced.
37456 Guix builds the image from scratch, not from a pre-existing Docker base
37457 image. As a result, it contains @emph{exactly} what you define in the
37458 operating system configuration file. You can then load the image and
37459 launch a Docker container using commands like the following:
37462 image_id="$(docker load < guix-system-docker-image.tar.gz)"
37463 container_id="$(docker create $image_id)"
37464 docker start $container_id
37467 This command starts a new Docker container from the specified image. It
37468 will boot the Guix system in the usual manner, which means it will
37469 start any services you have defined in the operating system
37470 configuration. You can get an interactive shell running in the container
37471 using @command{docker exec}:
37474 docker exec -ti $container_id /run/current-system/profile/bin/bash --login
37477 Depending on what you run in the Docker container, it
37478 may be necessary to give the container additional permissions. For
37479 example, if you intend to build software using Guix inside of the Docker
37480 container, you may need to pass the @option{--privileged} option to
37481 @code{docker create}.
37483 Last, the @option{--network} option applies to @command{guix system
37484 docker-image}: it produces an image where network is supposedly shared
37485 with the host, and thus without services like nscd or NetworkManager.
37488 Return a script to run the operating system declared in @var{file}
37489 within a container. Containers are a set of lightweight isolation
37490 mechanisms provided by the kernel Linux-libre. Containers are
37491 substantially less resource-demanding than full virtual machines since
37492 the kernel, shared objects, and other resources can be shared with the
37493 host system; this also means they provide thinner isolation.
37495 Currently, the script must be run as root in order to support more than
37496 a single user and group. The container shares its store with the host
37499 As with the @code{vm} action (@pxref{guix system vm}), additional file
37500 systems to be shared between the host and container can be specified
37501 using the @option{--share} and @option{--expose} options:
37504 guix system container my-config.scm \
37505 --expose=$HOME --share=$HOME/tmp=/exchange
37508 The @option{--share} and @option{--expose} options can also be passed to
37509 the generated script to bind-mount additional directories into the
37513 This option requires Linux-libre 3.19 or newer.
37518 @var{options} can contain any of the common build options (@pxref{Common
37519 Build Options}). In addition, @var{options} can contain one of the
37523 @item --expression=@var{expr}
37524 @itemx -e @var{expr}
37525 Consider the operating-system @var{expr} evaluates to.
37526 This is an alternative to specifying a file which evaluates to an
37528 This is used to generate the Guix system installer @pxref{Building the
37529 Installation Image}).
37531 @item --system=@var{system}
37532 @itemx -s @var{system}
37533 Attempt to build for @var{system} instead of the host system type.
37534 This works as per @command{guix build} (@pxref{Invoking guix build}).
37538 Return the derivation file name of the given operating system without
37541 @cindex provenance tracking, of the operating system
37542 @item --save-provenance
37543 As discussed above, @command{guix system init} and @command{guix system
37544 reconfigure} always save provenance information @i{via} a dedicated
37545 service (@pxref{Service Reference, @code{provenance-service-type}}).
37546 However, other commands don't do that by default. If you wish to, say,
37547 create a virtual machine image that contains provenance information, you
37551 guix system image -t qcow2 --save-provenance config.scm
37554 That way, the resulting image will effectively ``embed its own source''
37555 in the form of meta-data in @file{/run/current-system}. With that
37556 information, one can rebuild the image to make sure it really contains
37557 what it pretends to contain; or they could use that to derive a variant
37560 @item --image-type=@var{type}
37561 @itemx -t @var{type}
37562 For the @code{image} action, create an image with given @var{type}.
37564 When this option is omitted, @command{guix system} uses the
37565 @code{efi-raw} image type.
37567 @cindex ISO-9660 format
37568 @cindex CD image format
37569 @cindex DVD image format
37570 @option{--image-type=iso9660} produces an ISO-9660 image, suitable
37571 for burning on CDs and DVDs.
37573 @item --image-size=@var{size}
37574 For the @code{image} action, create an image of the given @var{size}.
37575 @var{size} may be a number of bytes, or it may include a unit as a
37576 suffix (@pxref{Block size, size specifications,, coreutils, GNU
37579 When this option is omitted, @command{guix system} computes an estimate
37580 of the image size as a function of the size of the system declared in
37585 For the @code{container} action, allow containers to access the host network,
37586 that is, do not create a network namespace.
37588 @item --root=@var{file}
37589 @itemx -r @var{file}
37590 Make @var{file} a symlink to the result, and register it as a garbage
37593 @item --skip-checks
37594 Skip pre-installation safety checks.
37596 By default, @command{guix system init} and @command{guix system
37597 reconfigure} perform safety checks: they make sure the file systems that
37598 appear in the @code{operating-system} declaration actually exist
37599 (@pxref{File Systems}), and that any Linux kernel modules that may be
37600 needed at boot time are listed in @code{initrd-modules} (@pxref{Initial
37601 RAM Disk}). Passing this option skips these tests altogether.
37603 @item --allow-downgrades
37604 Instruct @command{guix system reconfigure} to allow system downgrades.
37606 By default, @command{reconfigure} prevents you from downgrading your
37607 system. It achieves that by comparing the provenance info of your
37608 system (shown by @command{guix system describe}) with that of your
37609 @command{guix} command (shown by @command{guix describe}). If the
37610 commits for @command{guix} are not descendants of those used for your
37611 system, @command{guix system reconfigure} errors out. Passing
37612 @option{--allow-downgrades} allows you to bypass these checks.
37615 Make sure you understand its security implications before using
37616 @option{--allow-downgrades}.
37620 @cindex on-error strategy
37621 @cindex error strategy
37622 @item --on-error=@var{strategy}
37623 Apply @var{strategy} when an error occurs when reading @var{file}.
37624 @var{strategy} may be one of the following:
37627 @item nothing-special
37628 Report the error concisely and exit. This is the default strategy.
37631 Likewise, but also display a backtrace.
37634 Report the error and enter Guile's debugger. From there, you can run
37635 commands such as @code{,bt} to get a backtrace, @code{,locals} to
37636 display local variable values, and more generally inspect the state of the
37637 program. @xref{Debug Commands,,, guile, GNU Guile Reference Manual}, for
37638 a list of available debugging commands.
37642 Once you have built, configured, re-configured, and re-re-configured
37643 your Guix installation, you may find it useful to list the operating
37644 system generations available on disk---and that you can choose from the
37645 bootloader boot menu:
37650 Describe the running system generation: its file name, the kernel and
37651 bootloader used, etc., as well as provenance information when available.
37653 The @code{--list-installed} flag is available, with the same
37654 syntax that is used in @command{guix package --list-installed}
37655 (@pxref{Invoking guix package}). When the flag is used,
37656 the description will include a list of packages that are currently
37657 installed in the system profile, with optional filtering based on a
37658 regular expression.
37661 The @emph{running} system generation---referred to by
37662 @file{/run/current-system}---is not necessarily the @emph{current}
37663 system generation---referred to by @file{/var/guix/profiles/system}: it
37664 differs when, for instance, you chose from the bootloader menu to boot
37665 an older generation.
37667 It can also differ from the @emph{booted} system generation---referred
37668 to by @file{/run/booted-system}---for instance because you reconfigured
37669 the system in the meantime.
37672 @item list-generations
37673 List a summary of each generation of the operating system available on
37674 disk, in a human-readable way. This is similar to the
37675 @option{--list-generations} option of @command{guix package}
37676 (@pxref{Invoking guix package}).
37678 Optionally, one can specify a pattern, with the same syntax that is used
37679 in @command{guix package --list-generations}, to restrict the list of
37680 generations displayed. For instance, the following command displays
37681 generations that are up to 10 days old:
37684 $ guix system list-generations 10d
37687 The @code{--list-installed} flag may also be specified, with the same
37688 syntax that is used in @command{guix package --list-installed}. This
37689 may be helpful if trying to determine when a package was added to the
37694 The @command{guix system} command has even more to offer! The following
37695 sub-commands allow you to visualize how your system services relate to
37698 @anchor{system-extension-graph}
37701 @item extension-graph
37702 Emit to standard output the @dfn{service
37703 extension graph} of the operating system defined in @var{file}
37704 (@pxref{Service Composition}, for more information on service
37705 extensions). By default the output is in Dot/Graphviz format, but you
37706 can choose a different format with @option{--graph-backend}, as with
37707 @command{guix graph} (@pxref{Invoking guix graph, @option{--backend}}):
37712 $ guix system extension-graph @var{file} | xdot -
37715 shows the extension relations among services.
37718 The @command{dot} program is provided by the @code{graphviz} package.
37721 @anchor{system-shepherd-graph}
37722 @item shepherd-graph
37723 Emit to standard output the @dfn{dependency
37724 graph} of shepherd services of the operating system defined in
37725 @var{file}. @xref{Shepherd Services}, for more information and for an
37728 Again, the default output format is Dot/Graphviz, but you can pass
37729 @option{--graph-backend} to select a different one.
37733 @node Invoking guix deploy
37734 @section Invoking @code{guix deploy}
37736 We've already seen @code{operating-system} declarations used to manage a
37737 machine's configuration locally. Suppose you need to configure multiple
37738 machines, though---perhaps you're managing a service on the web that's
37739 comprised of several servers. @command{guix deploy} enables you to use those
37740 same @code{operating-system} declarations to manage multiple remote hosts at
37741 once as a logical ``deployment''.
37744 The functionality described in this section is still under development
37745 and is subject to change. Get in touch with us on
37746 @email{guix-devel@@gnu.org}!
37750 guix deploy @var{file}
37753 Such an invocation will deploy the machines that the code within @var{file}
37754 evaluates to. As an example, @var{file} might contain a definition like this:
37757 ;; This is a Guix deployment of a "bare bones" setup, with
37758 ;; no X11 display server, to a machine with an SSH daemon
37759 ;; listening on localhost:2222. A configuration such as this
37760 ;; may be appropriate for virtual machine with ports
37761 ;; forwarded to the host's loopback interface.
37763 (use-service-modules networking ssh)
37764 (use-package-modules bootloaders)
37768 (host-name "gnu-deployed")
37769 (timezone "Etc/UTC")
37770 (bootloader (bootloader-configuration
37771 (bootloader grub-bootloader)
37772 (targets '("/dev/vda"))
37773 (terminal-outputs '(console))))
37774 (file-systems (cons (file-system
37776 (device "/dev/vda1")
37778 %base-file-systems))
37780 (append (list (service dhcp-client-service-type)
37781 (service openssh-service-type
37782 (openssh-configuration
37783 (permit-root-login #t)
37784 (allow-empty-passwords? #t))))
37788 (operating-system %system)
37789 (environment managed-host-environment-type)
37790 (configuration (machine-ssh-configuration
37791 (host-name "localhost")
37792 (system "x86_64-linux")
37794 (identity "./id_rsa")
37798 The file should evaluate to a list of @var{machine} objects. This example,
37799 upon being deployed, will create a new generation on the remote system
37800 realizing the @code{operating-system} declaration @code{%system}.
37801 @code{environment} and @code{configuration} specify how the machine should be
37802 provisioned---that is, how the computing resources should be created and
37803 managed. The above example does not create any resources, as a
37804 @code{'managed-host} is a machine that is already running the Guix system and
37805 available over the network. This is a particularly simple case; a more
37806 complex deployment may involve, for example, starting virtual machines through
37807 a Virtual Private Server (VPS) provider. In such a case, a different
37808 @var{environment} type would be used.
37810 Do note that you first need to generate a key pair on the coordinator machine
37811 to allow the daemon to export signed archives of files from the store
37812 (@pxref{Invoking guix archive}), though this step is automatic on Guix
37816 # guix archive --generate-key
37820 Each target machine must authorize the key of the master machine so that it
37821 accepts store items it receives from the coordinator:
37824 # guix archive --authorize < coordinator-public-key.txt
37827 @code{user}, in this example, specifies the name of the user account to log in
37828 as to perform the deployment. Its default value is @code{root}, but root
37829 login over SSH may be forbidden in some cases. To work around this,
37830 @command{guix deploy} can log in as an unprivileged user and employ
37831 @code{sudo} to escalate privileges. This will only work if @code{sudo} is
37832 currently installed on the remote and can be invoked non-interactively as
37833 @code{user}. That is, the line in @code{sudoers} granting @code{user} the
37834 ability to use @code{sudo} must contain the @code{NOPASSWD} tag. This can
37835 be accomplished with the following operating system configuration snippet:
37839 (gnu system)) ;for %sudoers-specification
37841 (define %user "username")
37846 (plain-file "sudoers"
37847 (string-append (plain-file-content %sudoers-specification)
37848 (format #f "~a ALL = NOPASSWD: ALL~%"
37853 For more information regarding the format of the @file{sudoers} file,
37854 consult @command{man sudoers}.
37856 Once you've deployed a system on a set of machines, you may find it
37857 useful to run a command on all of them. The @option{--execute} or
37858 @option{-x} option lets you do that; the example below runs
37859 @command{uname -a} on all the machines listed in the deployment file:
37862 guix deploy @var{file} -x -- uname -a
37865 One thing you may often need to do after deployment is restart specific
37866 services on all the machines, which you can do like so:
37869 guix deploy @var{file} -x -- herd restart @var{service}
37872 The @command{guix deploy -x} command returns zero if and only if the
37873 command succeeded on all the machines.
37875 @c FIXME/TODO: Separate the API doc from the CLI doc.
37877 Below are the data types you need to know about when writing a
37880 @deftp {Data Type} machine
37881 This is the data type representing a single machine in a heterogeneous Guix
37885 @item @code{operating-system}
37886 The object of the operating system configuration to deploy.
37888 @item @code{environment}
37889 An @code{environment-type} describing how the machine should be provisioned.
37891 @item @code{configuration} (default: @code{#f})
37892 An object describing the configuration for the machine's @code{environment}.
37893 If the @code{environment} has a default configuration, @code{#f} may be used.
37894 If @code{#f} is used for an environment with no default configuration,
37895 however, an error will be thrown.
37899 @deftp {Data Type} machine-ssh-configuration
37900 This is the data type representing the SSH client parameters for a machine
37901 with an @code{environment} of @code{managed-host-environment-type}.
37904 @item @code{host-name}
37905 @item @code{build-locally?} (default: @code{#t})
37906 If false, system derivations will be built on the machine being deployed to.
37907 @item @code{system}
37908 The system type describing the architecture of the machine being deployed
37909 to---e.g., @code{"x86_64-linux"}.
37910 @item @code{authorize?} (default: @code{#t})
37911 If true, the coordinator's signing key will be added to the remote's ACL
37913 @item @code{port} (default: @code{22})
37914 @item @code{user} (default: @code{"root"})
37915 @item @code{identity} (default: @code{#f})
37916 If specified, the path to the SSH private key to use to authenticate with the
37919 @item @code{host-key} (default: @code{#f})
37920 This should be the SSH host key of the machine, which looks like this:
37923 ssh-ed25519 AAAAC3Nz@dots{} root@@example.org
37926 When @code{host-key} is @code{#f}, the server is authenticated against
37927 the @file{~/.ssh/known_hosts} file, just like the OpenSSH @command{ssh}
37930 @item @code{allow-downgrades?} (default: @code{#f})
37931 Whether to allow potential downgrades.
37933 Like @command{guix system reconfigure}, @command{guix deploy} compares
37934 the channel commits currently deployed on the remote host (as returned
37935 by @command{guix system describe}) to those currently in use (as
37936 returned by @command{guix describe}) to determine whether commits
37937 currently in use are descendants of those deployed. When this is not
37938 the case and @code{allow-downgrades?} is false, it raises an error.
37939 This ensures you do not accidentally downgrade remote machines.
37941 @item @code{safety-checks?} (default: @code{#t})
37942 Whether to perform ``safety checks'' before deployment. This includes
37943 verifying that devices and file systems referred to in the operating
37944 system configuration actually exist on the target machine, and making
37945 sure that Linux modules required to access storage devices at boot time
37946 are listed in the @code{initrd-modules} field of the operating system.
37948 These safety checks ensure that you do not inadvertently deploy a system
37949 that would fail to boot. Be careful before turning them off!
37953 @deftp {Data Type} digital-ocean-configuration
37954 This is the data type describing the Droplet that should be created for a
37955 machine with an @code{environment} of @code{digital-ocean-environment-type}.
37958 @item @code{ssh-key}
37959 The path to the SSH private key to use to authenticate with the remote
37960 host. In the future, this field may not exist.
37962 A list of string ``tags'' that uniquely identify the machine. Must be given
37963 such that no two machines in the deployment have the same set of tags.
37964 @item @code{region}
37965 A Digital Ocean region slug, such as @code{"nyc3"}.
37967 A Digital Ocean size slug, such as @code{"s-1vcpu-1gb"}
37968 @item @code{enable-ipv6?}
37969 Whether or not the droplet should be created with IPv6 networking.
37973 @node Running Guix in a VM
37974 @section Running Guix in a Virtual Machine
37976 @cindex virtual machine
37977 To run Guix in a virtual machine (VM), one can use the pre-built Guix VM
37978 image distributed at
37979 @url{@value{BASE-URL}/guix-system-vm-image-@value{VERSION}.x86_64-linux.qcow2}.
37980 This image is a compressed image in QCOW format. You can pass it to an
37981 emulator such as @uref{https://qemu.org/, QEMU} (see below for details).
37983 This image boots the Xfce graphical environment and it contains some
37984 commonly used tools. You can install more software in the image by running
37985 @command{guix package} in a terminal (@pxref{Invoking guix package}). You can
37986 also reconfigure the system based on its initial configuration file available
37987 as @file{/run/current-system/configuration.scm} (@pxref{Using the
37988 Configuration System}).
37990 Instead of using this pre-built image, one can also build their own
37991 image using @command{guix system image} (@pxref{Invoking guix system}).
37994 If you built your own image, you must copy it out of the store
37995 (@pxref{The Store}) and give yourself permission to write to the copy
37996 before you can use it. When invoking QEMU, you must choose a system
37997 emulator that is suitable for your hardware platform. Here is a minimal
37998 QEMU invocation that will boot the result of @command{guix system
37999 image -t qcow2} on x86_64 hardware:
38002 $ qemu-system-x86_64 \
38003 -nic user,model=virtio-net-pci \
38004 -enable-kvm -m 1024 \
38005 -device virtio-blk,drive=myhd \
38006 -drive if=none,file=/tmp/qemu-image,id=myhd
38009 Here is what each of these options means:
38012 @item qemu-system-x86_64
38013 This specifies the hardware platform to emulate. This should match the
38016 @item -nic user,model=virtio-net-pci
38017 Enable the unprivileged user-mode network stack. The guest OS can
38018 access the host but not vice versa. This is the simplest way to get the
38019 guest OS online. @code{model} specifies which network device to emulate:
38020 @code{virtio-net-pci} is a special device made for virtualized operating
38021 systems and recommended for most uses. Assuming your hardware platform is
38022 x86_64, you can get a list of available NIC models by running
38023 @command{qemu-system-x86_64 -nic model=help}.
38026 If your system has hardware virtualization extensions, enabling the
38027 virtual machine support (KVM) of the Linux kernel will make things run
38030 @c To run Xfce + 'guix pull', we need at least 1G of RAM.
38032 RAM available to the guest OS, in mebibytes. Defaults to 128@tie{}MiB,
38033 which may be insufficient for some operations.
38035 @item -device virtio-blk,drive=myhd
38036 Create a @code{virtio-blk} drive called ``myhd''. @code{virtio-blk} is a
38037 ``paravirtualization'' mechanism for block devices that allows QEMU to achieve
38038 better performance than if it were emulating a complete disk drive. See the
38039 QEMU and KVM documentation for more info.
38041 @item -drive if=none,file=/tmp/qemu-image,id=myhd
38042 Use our QCOW image, the @file{/tmp/qemu-image} file, as the backing
38043 store of the ``myhd'' drive.
38046 The default @command{run-vm.sh} script that is returned by an invocation of
38047 @command{guix system vm} does not add a @command{-nic user} flag by default.
38048 To get network access from within the vm add the @code{(dhcp-client-service)}
38049 to your system definition and start the VM using
38050 @command{$(guix system vm config.scm) -nic user}. An important caveat of using
38051 @command{-nic user} for networking is that @command{ping} will not work, because
38052 it uses the ICMP protocol. You'll have to use a different command to check for
38053 network connectivity, for example @command{guix download}.
38055 @subsection Connecting Through SSH
38059 To enable SSH inside a VM you need to add an SSH server like
38060 @code{openssh-service-type} to your VM (@pxref{Networking Services,
38061 @code{openssh-service-type}}). In addition you need to forward the SSH port,
38062 22 by default, to the host. You can do this with
38065 $(guix system vm config.scm) -nic user,model=virtio-net-pci,hostfwd=tcp::10022-:22
38068 To connect to the VM you can run
38071 ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -p 10022 localhost
38074 The @command{-p} tells @command{ssh} the port you want to connect to.
38075 @command{-o UserKnownHostsFile=/dev/null} prevents @command{ssh} from complaining
38076 every time you modify your @command{config.scm} file and the
38077 @command{-o StrictHostKeyChecking=no} prevents you from having to allow a
38078 connection to an unknown host every time you connect.
38081 If you find the above @samp{hostfwd} example not to be working (e.g.,
38082 your SSH client hangs attempting to connect to the mapped port of your
38083 VM), make sure that your Guix System VM has networking support, such as
38084 by using the @code{dhcp-client-service-type} service type.
38087 @subsection Using @command{virt-viewer} with Spice
38089 As an alternative to the default @command{qemu} graphical client you can
38090 use the @command{remote-viewer} from the @command{virt-viewer} package. To
38091 connect pass the @command{-spice port=5930,disable-ticketing} flag to
38092 @command{qemu}. See previous section for further information on how to do this.
38094 Spice also allows you to do some nice stuff like share your clipboard with your
38095 VM@. To enable that you'll also have to pass the following flags to @command{qemu}:
38098 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5
38099 -chardev spicevmc,name=vdagent,id=vdagent
38100 -device virtserialport,nr=1,bus=virtio-serial0.0,chardev=vdagent,\
38101 name=com.redhat.spice.0
38104 You'll also need to add the @code{(spice-vdagent-service)} to your
38105 system definition (@pxref{Miscellaneous Services, Spice service}).
38107 @node Defining Services
38108 @section Defining Services
38110 The previous sections show the available services and how one can combine
38111 them in an @code{operating-system} declaration. But how do we define
38112 them in the first place? And what is a service anyway?
38115 * Service Composition:: The model for composing services.
38116 * Service Types and Services:: Types and services.
38117 * Service Reference:: API reference.
38118 * Shepherd Services:: A particular type of service.
38119 * Complex Configurations:: Defining bindings for complex configurations.
38122 @node Service Composition
38123 @subsection Service Composition
38127 Here we define a @dfn{service} as, broadly, something that extends the
38128 functionality of the operating system. Often a service is a process---a
38129 @dfn{daemon}---started when the system boots: a secure shell server, a
38130 Web server, the Guix build daemon, etc. Sometimes a service is a daemon
38131 whose execution can be triggered by another daemon---e.g., an FTP server
38132 started by @command{inetd} or a D-Bus service activated by
38133 @command{dbus-daemon}. Occasionally, a service does not map to a
38134 daemon. For instance, the ``account'' service collects user accounts
38135 and makes sure they exist when the system runs; the ``udev'' service
38136 collects device management rules and makes them available to the eudev
38137 daemon; the @file{/etc} service populates the @file{/etc} directory
38140 @cindex service extensions
38141 Guix system services are connected by @dfn{extensions}. For instance, the
38142 secure shell service @emph{extends} the Shepherd---the
38143 initialization system, running as PID@tie{}1---by giving it the command
38144 lines to start and stop the secure shell daemon (@pxref{Networking
38145 Services, @code{openssh-service-type}}); the UPower service extends the D-Bus
38146 service by passing it its @file{.service} specification, and extends the
38147 udev service by passing it device management rules (@pxref{Desktop
38148 Services, @code{upower-service}}); the Guix daemon service extends the
38149 Shepherd by passing it the command lines to start and stop the daemon,
38150 and extends the account service by passing it a list of required build
38151 user accounts (@pxref{Base Services}).
38153 All in all, services and their ``extends'' relations form a directed
38154 acyclic graph (DAG). If we represent services as boxes and extensions
38155 as arrows, a typical system might provide something like this:
38157 @image{images/service-graph,,5in,Typical service extension graph.}
38159 @cindex system service
38160 At the bottom, we see the @dfn{system service}, which produces the
38161 directory containing everything to run and boot the system, as returned
38162 by the @command{guix system build} command. @xref{Service Reference},
38163 to learn about the other service types shown here.
38164 @xref{system-extension-graph, the @command{guix system extension-graph}
38165 command}, for information on how to generate this representation for a
38166 particular operating system definition.
38168 @cindex service types
38169 Technically, developers can define @dfn{service types} to express these
38170 relations. There can be any number of services of a given type on the
38171 system---for instance, a system running two instances of the GNU secure
38172 shell server (lsh) has two instances of @code{lsh-service-type}, with
38173 different parameters.
38175 The following section describes the programming interface for service
38176 types and services.
38178 @node Service Types and Services
38179 @subsection Service Types and Services
38181 A @dfn{service type} is a node in the DAG described above. Let us start
38182 with a simple example, the service type for the Guix build daemon
38183 (@pxref{Invoking guix-daemon}):
38186 (define guix-service-type
38190 (list (service-extension shepherd-root-service-type guix-shepherd-service)
38191 (service-extension account-service-type guix-accounts)
38192 (service-extension activation-service-type guix-activation)))
38193 (default-value (guix-configuration))))
38197 It defines three things:
38201 A name, whose sole purpose is to make inspection and debugging easier.
38204 A list of @dfn{service extensions}, where each extension designates the
38205 target service type and a procedure that, given the parameters of the
38206 service, returns a list of objects to extend the service of that type.
38208 Every service type has at least one service extension. The only
38209 exception is the @dfn{boot service type}, which is the ultimate service.
38212 Optionally, a default value for instances of this type.
38215 In this example, @code{guix-service-type} extends three services:
38218 @item shepherd-root-service-type
38219 The @code{guix-shepherd-service} procedure defines how the Shepherd
38220 service is extended. Namely, it returns a @code{<shepherd-service>}
38221 object that defines how @command{guix-daemon} is started and stopped
38222 (@pxref{Shepherd Services}).
38224 @item account-service-type
38225 This extension for this service is computed by @code{guix-accounts},
38226 which returns a list of @code{user-group} and @code{user-account}
38227 objects representing the build user accounts (@pxref{Invoking
38230 @item activation-service-type
38231 Here @code{guix-activation} is a procedure that returns a gexp, which is
38232 a code snippet to run at ``activation time''---e.g., when the service is
38236 A service of this type is instantiated like this:
38239 (service guix-service-type
38240 (guix-configuration
38242 (extra-options '("--gc-keep-derivations"))))
38245 The second argument to the @code{service} form is a value representing
38246 the parameters of this specific service instance.
38247 @xref{guix-configuration-type, @code{guix-configuration}}, for
38248 information about the @code{guix-configuration} data type. When the
38249 value is omitted, the default value specified by
38250 @code{guix-service-type} is used:
38253 (service guix-service-type)
38256 @code{guix-service-type} is quite simple because it extends other
38257 services but is not extensible itself.
38259 @c @subsubsubsection Extensible Service Types
38261 The service type for an @emph{extensible} service looks like this:
38264 (define udev-service-type
38265 (service-type (name 'udev)
38267 (list (service-extension shepherd-root-service-type
38268 udev-shepherd-service)))
38270 (compose concatenate) ;concatenate the list of rules
38271 (extend (lambda (config rules)
38273 (($ <udev-configuration> udev initial-rules)
38274 (udev-configuration
38275 (udev udev) ;the udev package to use
38276 (rules (append initial-rules rules)))))))))
38279 This is the service type for the
38280 @uref{https://wiki.gentoo.org/wiki/Project:Eudev, eudev device
38281 management daemon}. Compared to the previous example, in addition to an
38282 extension of @code{shepherd-root-service-type}, we see two new fields:
38286 This is the procedure to @dfn{compose} the list of extensions to
38287 services of this type.
38289 Services can extend the udev service by passing it lists of rules; we
38290 compose those extensions simply by concatenating them.
38293 This procedure defines how the value of the service is @dfn{extended} with
38294 the composition of the extensions.
38296 Udev extensions are composed into a list of rules, but the udev service
38297 value is itself a @code{<udev-configuration>} record. So here, we
38298 extend that record by appending the list of rules it contains to the
38299 list of contributed rules.
38302 This is a string giving an overview of the service type. The string can
38303 contain Texinfo markup (@pxref{Overview,,, texinfo, GNU Texinfo}). The
38304 @command{guix system search} command searches these strings and displays
38305 them (@pxref{Invoking guix system}).
38308 There can be only one instance of an extensible service type such as
38309 @code{udev-service-type}. If there were more, the
38310 @code{service-extension} specifications would be ambiguous.
38312 Still here? The next section provides a reference of the programming
38313 interface for services.
38315 @node Service Reference
38316 @subsection Service Reference
38318 We have seen an overview of service types (@pxref{Service Types and
38319 Services}). This section provides a reference on how to manipulate
38320 services and service types. This interface is provided by the
38321 @code{(gnu services)} module.
38323 @deffn {Scheme Procedure} service @var{type} [@var{value}]
38324 Return a new service of @var{type}, a @code{<service-type>} object (see
38325 below). @var{value} can be any object; it represents the parameters of
38326 this particular service instance.
38328 When @var{value} is omitted, the default value specified by @var{type}
38329 is used; if @var{type} does not specify a default value, an error is
38332 For instance, this:
38335 (service openssh-service-type)
38339 is equivalent to this:
38342 (service openssh-service-type
38343 (openssh-configuration))
38346 In both cases the result is an instance of @code{openssh-service-type}
38347 with the default configuration.
38350 @deffn {Scheme Procedure} service? @var{obj}
38351 Return true if @var{obj} is a service.
38354 @deffn {Scheme Procedure} service-kind @var{service}
38355 Return the type of @var{service}---i.e., a @code{<service-type>} object.
38358 @deffn {Scheme Procedure} service-value @var{service}
38359 Return the value associated with @var{service}. It represents its
38363 Here is an example of how a service is created and manipulated:
38367 (service nginx-service-type
38368 (nginx-configuration
38370 (log-directory log-directory)
38371 (run-directory run-directory)
38372 (file config-file))))
38377 (eq? (service-kind s) nginx-service-type)
38381 The @code{modify-services} form provides a handy way to change the
38382 parameters of some of the services of a list such as
38383 @code{%base-services} (@pxref{Base Services, @code{%base-services}}). It
38384 evaluates to a list of services. Of course, you could always use
38385 standard list combinators such as @code{map} and @code{fold} to do that
38386 (@pxref{SRFI-1, List Library,, guile, GNU Guile Reference Manual});
38387 @code{modify-services} simply provides a more concise form for this
38390 @deffn {Scheme Syntax} modify-services @var{services} @
38391 (@var{type} @var{variable} => @var{body}) @dots{}
38393 Modify the services listed in @var{services} according to the given
38394 clauses. Each clause has the form:
38397 (@var{type} @var{variable} => @var{body})
38400 where @var{type} is a service type---e.g.,
38401 @code{guix-service-type}---and @var{variable} is an identifier that is
38402 bound within the @var{body} to the service parameters---e.g., a
38403 @code{guix-configuration} instance---of the original service of that
38406 The @var{body} should evaluate to the new service parameters, which will
38407 be used to configure the new service. This new service will replace the
38408 original in the resulting list. Because a service's service parameters
38409 are created using @code{define-record-type*}, you can write a succinct
38410 @var{body} that evaluates to the new service parameters by using the
38411 @code{inherit} feature that @code{define-record-type*} provides.
38413 Clauses can also have the following form:
38416 (delete @var{type})
38419 Such a clause removes all services of the given @var{type} from
38422 @xref{Using the Configuration System}, for example usage.
38426 Next comes the programming interface for service types. This is
38427 something you want to know when writing new service definitions, but not
38428 necessarily when simply looking for ways to customize your
38429 @code{operating-system} declaration.
38431 @deftp {Data Type} service-type
38432 @cindex service type
38433 This is the representation of a @dfn{service type} (@pxref{Service Types
38438 This is a symbol, used only to simplify inspection and debugging.
38440 @item @code{extensions}
38441 A non-empty list of @code{<service-extension>} objects (see below).
38443 @item @code{compose} (default: @code{#f})
38444 If this is @code{#f}, then the service type denotes services that cannot
38445 be extended---i.e., services that do not receive ``values'' from other
38448 Otherwise, it must be a one-argument procedure. The procedure is called
38449 by @code{fold-services} and is passed a list of values collected from
38450 extensions. It may return any single value.
38452 @item @code{extend} (default: @code{#f})
38453 If this is @code{#f}, services of this type cannot be extended.
38455 Otherwise, it must be a two-argument procedure: @code{fold-services}
38456 calls it, passing it the initial value of the service as the first
38457 argument and the result of applying @code{compose} to the extension
38458 values as the second argument. It must return a value that is a valid
38459 parameter value for the service instance.
38461 @item @code{description}
38462 This is a string, possibly using Texinfo markup, describing in a couple
38463 of sentences what the service is about. This string allows users to
38464 find about the service through @command{guix system search}
38465 (@pxref{Invoking guix system}).
38467 @item @code{default-value} (default: @code{&no-default-value})
38468 The default value associated for instances of this service type. This
38469 allows users to use the @code{service} form without its second argument:
38472 (service @var{type})
38475 The returned service in this case has the default value specified by
38479 @xref{Service Types and Services}, for examples.
38482 @deffn {Scheme Procedure} service-extension @var{target-type} @
38484 Return a new extension for services of type @var{target-type}.
38485 @var{compute} must be a one-argument procedure: @code{fold-services}
38486 calls it, passing it the value associated with the service that provides
38487 the extension; it must return a valid value for the target service.
38490 @deffn {Scheme Procedure} service-extension? @var{obj}
38491 Return true if @var{obj} is a service extension.
38494 Occasionally, you might want to simply extend an existing service. This
38495 involves creating a new service type and specifying the extension of
38496 interest, which can be verbose; the @code{simple-service} procedure
38497 provides a shorthand for this.
38499 @deffn {Scheme Procedure} simple-service @var{name} @var{target} @var{value}
38500 Return a service that extends @var{target} with @var{value}. This works
38501 by creating a singleton service type @var{name}, of which the returned
38502 service is an instance.
38504 For example, this extends mcron (@pxref{Scheduled Job Execution}) with
38508 (simple-service 'my-mcron-job mcron-service-type
38509 #~(job '(next-hour (3)) "guix gc -F 2G"))
38513 At the core of the service abstraction lies the @code{fold-services}
38514 procedure, which is responsible for ``compiling'' a list of services
38515 down to a single directory that contains everything needed to boot and
38516 run the system---the directory shown by the @command{guix system build}
38517 command (@pxref{Invoking guix system}). In essence, it propagates
38518 service extensions down the service graph, updating each node parameters
38519 on the way, until it reaches the root node.
38521 @deffn {Scheme Procedure} fold-services @var{services} @
38522 [#:target-type @var{system-service-type}]
38523 Fold @var{services} by propagating their extensions down to the root of
38524 type @var{target-type}; return the root service adjusted accordingly.
38527 Lastly, the @code{(gnu services)} module also defines several essential
38528 service types, some of which are listed below.
38530 @defvr {Scheme Variable} system-service-type
38531 This is the root of the service graph. It produces the system directory
38532 as returned by the @command{guix system build} command.
38535 @defvr {Scheme Variable} boot-service-type
38536 The type of the ``boot service'', which produces the @dfn{boot script}.
38537 The boot script is what the initial RAM disk runs when booting.
38540 @defvr {Scheme Variable} etc-service-type
38541 The type of the @file{/etc} service. This service is used to create
38542 files under @file{/etc} and can be extended by
38543 passing it name/file tuples such as:
38546 (list `("issue" ,(plain-file "issue" "Welcome!\n")))
38549 In this example, the effect would be to add an @file{/etc/issue} file
38550 pointing to the given file.
38553 @defvr {Scheme Variable} setuid-program-service-type
38554 Type for the ``setuid-program service''. This service collects lists of
38555 executable file names, passed as gexps, and adds them to the set of
38556 setuid and setgid programs on the system (@pxref{Setuid Programs}).
38559 @defvr {Scheme Variable} profile-service-type
38560 Type of the service that populates the @dfn{system profile}---i.e., the
38561 programs under @file{/run/current-system/profile}. Other services can
38562 extend it by passing it lists of packages to add to the system profile.
38565 @cindex provenance tracking, of the operating system
38566 @anchor{provenance-service-type}
38567 @defvr {Scheme Variable} provenance-service-type
38568 This is the type of the service that records @dfn{provenance meta-data}
38569 in the system itself. It creates several files under
38570 @file{/run/current-system}:
38574 This is a ``channel file'' that can be passed to @command{guix pull -C}
38575 or @command{guix time-machine -C}, and which describes the channels used
38576 to build the system, if that information was available
38577 (@pxref{Channels}).
38579 @item configuration.scm
38580 This is the file that was passed as the value for this
38581 @code{provenance-service-type} service. By default, @command{guix
38582 system reconfigure} automatically passes the OS configuration file it
38583 received on the command line.
38586 This contains the same information as the two other files but in a
38587 format that is more readily processable.
38590 In general, these two pieces of information (channels and configuration
38591 file) are enough to reproduce the operating system ``from source''.
38594 This information is necessary to rebuild your operating system, but it
38595 is not always sufficient. In particular, @file{configuration.scm}
38596 itself is insufficient if it is not self-contained---if it refers to
38597 external Guile modules or to extra files. If you want
38598 @file{configuration.scm} to be self-contained, we recommend that modules
38599 or files it refers to be part of a channel.
38601 Besides, provenance meta-data is ``silent'' in the sense that it does
38602 not change the bits contained in your system, @emph{except for the
38603 meta-data bits themselves}. Two different OS configurations or sets of
38604 channels can lead to the same system, bit-for-bit; when
38605 @code{provenance-service-type} is used, these two systems will have
38606 different meta-data and thus different store file names, which makes
38607 comparison less trivial.
38610 This service is automatically added to your operating system
38611 configuration when you use @command{guix system reconfigure},
38612 @command{guix system init}, or @command{guix deploy}.
38615 @defvr {Scheme Variable} linux-loadable-module-service-type
38616 Type of the service that collects lists of packages containing
38617 kernel-loadable modules, and adds them to the set of kernel-loadable
38620 This service type is intended to be extended by other service types,
38624 (simple-service 'installing-module
38625 linux-loadable-module-service-type
38626 (list module-to-install-1
38627 module-to-install-2))
38630 This does not actually load modules at bootup, only adds it to the
38631 kernel profile so that it @emph{can} be loaded by other means.
38634 @node Shepherd Services
38635 @subsection Shepherd Services
38637 @cindex shepherd services
38639 @cindex init system
38640 The @code{(gnu services shepherd)} module provides a way to define
38641 services managed by the GNU@tie{}Shepherd, which is the
38642 initialization system---the first process that is started when the
38643 system boots, also known as PID@tie{}1
38644 (@pxref{Introduction,,, shepherd, The GNU Shepherd Manual}).
38646 Services in the Shepherd can depend on each other. For instance, the
38647 SSH daemon may need to be started after the syslog daemon has been
38648 started, which in turn can only happen once all the file systems have
38649 been mounted. The simple operating system defined earlier (@pxref{Using
38650 the Configuration System}) results in a service graph like this:
38652 @image{images/shepherd-graph,,5in,Typical shepherd service graph.}
38654 You can actually generate such a graph for any operating system
38655 definition using the @command{guix system shepherd-graph} command
38656 (@pxref{system-shepherd-graph, @command{guix system shepherd-graph}}).
38658 The @code{%shepherd-root-service} is a service object representing
38659 PID@tie{}1, of type @code{shepherd-root-service-type}; it can be extended
38660 by passing it lists of @code{<shepherd-service>} objects.
38662 @deftp {Data Type} shepherd-service
38663 The data type representing a service managed by the Shepherd.
38666 @item @code{provision}
38667 This is a list of symbols denoting what the service provides.
38669 These are the names that may be passed to @command{herd start},
38670 @command{herd status}, and similar commands (@pxref{Invoking herd,,,
38671 shepherd, The GNU Shepherd Manual}). @xref{Slots of services, the
38672 @code{provides} slot,, shepherd, The GNU Shepherd Manual}, for details.
38674 @item @code{requirement} (default: @code{'()})
38675 List of symbols denoting the Shepherd services this one depends on.
38677 @cindex one-shot services, for the Shepherd
38678 @item @code{one-shot?} (default: @code{#f})
38679 Whether this service is @dfn{one-shot}. One-shot services stop immediately
38680 after their @code{start} action has completed. @xref{Slots of services,,,
38681 shepherd, The GNU Shepherd Manual}, for more info.
38683 @item @code{respawn?} (default: @code{#t})
38684 Whether to restart the service when it stops, for instance when the
38685 underlying process dies.
38688 @itemx @code{stop} (default: @code{#~(const #f)})
38689 The @code{start} and @code{stop} fields refer to the Shepherd's
38690 facilities to start and stop processes (@pxref{Service De- and
38691 Constructors,,, shepherd, The GNU Shepherd Manual}). They are given as
38692 G-expressions that get expanded in the Shepherd configuration file
38693 (@pxref{G-Expressions}).
38695 @item @code{actions} (default: @code{'()})
38696 @cindex actions, of Shepherd services
38697 This is a list of @code{shepherd-action} objects (see below) defining
38698 @dfn{actions} supported by the service, in addition to the standard
38699 @code{start} and @code{stop} actions. Actions listed here become available as
38700 @command{herd} sub-commands:
38703 herd @var{action} @var{service} [@var{arguments}@dots{}]
38706 @item @code{auto-start?} (default: @code{#t})
38707 Whether this service should be started automatically by the Shepherd. If it
38708 is @code{#f} the service has to be started manually with @code{herd start}.
38710 @item @code{documentation}
38711 A documentation string, as shown when running:
38714 herd doc @var{service-name}
38717 where @var{service-name} is one of the symbols in @code{provision}
38718 (@pxref{Invoking herd,,, shepherd, The GNU Shepherd Manual}).
38720 @item @code{modules} (default: @code{%default-modules})
38721 This is the list of modules that must be in scope when @code{start} and
38722 @code{stop} are evaluated.
38727 The example below defines a Shepherd service that spawns
38728 @command{syslogd}, the system logger from the GNU Networking Utilities
38729 (@pxref{syslogd invocation, @command{syslogd},, inetutils, GNU
38733 (let ((config (plain-file "syslogd.conf" "@dots{}")))
38735 (documentation "Run the syslog daemon (syslogd).")
38736 (provision '(syslogd))
38737 (requirement '(user-processes))
38738 (start #~(make-forkexec-constructor
38739 (list #$(file-append inetutils "/libexec/syslogd")
38740 "--rcfile" #$config)
38741 #:pid-file "/var/run/syslog.pid"))
38742 (stop #~(make-kill-destructor))))
38745 Key elements in this example are the @code{start} and @code{stop}
38746 fields: they are @dfn{staged} code snippets that use the
38747 @code{make-forkexec-constructor} procedure provided by the Shepherd and
38748 its dual, @code{make-kill-destructor} (@pxref{Service De- and
38749 Constructors,,, shepherd, The GNU Shepherd Manual}). The @code{start}
38750 field will have @command{shepherd} spawn @command{syslogd} with the
38751 given option; note that we pass @code{config} after @option{--rcfile},
38752 which is a configuration file declared above (contents of this file are
38753 omitted). Likewise, the @code{stop} field tells how this service is to
38754 be stopped; in this case, it is stopped by making the @code{kill} system
38755 call on its PID@. Code staging is achieved using G-expressions:
38756 @code{#~} stages code, while @code{#$} ``escapes'' back to host code
38757 (@pxref{G-Expressions}).
38759 @deftp {Data Type} shepherd-action
38760 This is the data type that defines additional actions implemented by a
38761 Shepherd service (see above).
38765 Symbol naming the action.
38767 @item documentation
38768 This is a documentation string for the action. It can be viewed by running:
38771 herd doc @var{service} action @var{action}
38775 This should be a gexp that evaluates to a procedure of at least one argument,
38776 which is the ``running value'' of the service (@pxref{Slots of services,,,
38777 shepherd, The GNU Shepherd Manual}).
38780 The following example defines an action called @code{say-hello} that kindly
38786 (documentation "Say hi!")
38787 (procedure #~(lambda (running . args)
38788 (format #t "Hello, friend! arguments: ~s\n"
38793 Assuming this action is added to the @code{example} service, then you can do:
38796 # herd say-hello example
38797 Hello, friend! arguments: ()
38798 # herd say-hello example a b c
38799 Hello, friend! arguments: ("a" "b" "c")
38802 This, as you can see, is a fairly sophisticated way to say hello.
38803 @xref{Service Convenience,,, shepherd, The GNU Shepherd Manual}, for more
38807 @defvr {Scheme Variable} shepherd-root-service-type
38808 The service type for the Shepherd ``root service''---i.e., PID@tie{}1.
38810 This is the service type that extensions target when they want to create
38811 shepherd services (@pxref{Service Types and Services}, for an example).
38812 Each extension must pass a list of @code{<shepherd-service>}. Its
38813 value must be a @code{shepherd-configuration}, as described below.
38816 @deftp {Data Type} shepherd-configuration
38817 This data type represents the Shepherd's configuration.
38820 @item shepherd (default: @code{shepherd})
38821 The Shepherd package to use.
38823 @item services (default: @code{'()})
38824 A list of @code{<shepherd-service>} to start.
38825 You should probably use the service extension
38826 mechanism instead (@pxref{Shepherd Services}).
38830 The following example specifies the Shepherd package for the operating
38836 (services (append (list openssh-service-type))
38840 ;; Use own Shepherd package.
38841 (essential-services
38842 (modify-services (operating-system-default-essential-services
38843 this-operating-system)
38844 (shepherd-root-service-type config => (shepherd-configuration
38846 (shepherd my-shepherd))))))
38849 @defvr {Scheme Variable} %shepherd-root-service
38850 This service represents PID@tie{}1.
38853 @node Complex Configurations
38854 @subsection Complex Configurations
38855 @cindex complex configurations
38856 Some programs might have rather complex configuration files or formats,
38857 and to make it easier to create Scheme bindings for these configuration
38858 files, you can use the utilities defined in the @code{(gnu services
38859 configuration)} module.
38861 The main utility is the @code{define-configuration} macro, which you
38862 will use to define a Scheme record type (@pxref{Record Overview,,,
38863 guile, GNU Guile Reference Manual}). The Scheme record will be
38864 serialized to a configuration file by using @dfn{serializers}, which are
38865 procedures that take some kind of Scheme value and returns a
38866 G-expression (@pxref{G-Expressions}), which should, once serialized to
38867 the disk, return a string. More details are listed below.
38869 @deffn {Scheme Syntax} define-configuration @var{name} @var{clause1} @
38871 Create a record type named @code{@var{name}} that contains the
38872 fields found in the clauses.
38874 A clause can have one of the following forms:
38878 (@var{type} @var{default-value})
38879 @var{documentation})
38882 (@var{type} @var{default-value})
38883 @var{documentation}
38888 @var{documentation})
38892 @var{documentation}
38896 @var{field-name} is an identifier that denotes the name of the field in
38897 the generated record.
38899 @var{type} is the type of the value corresponding to @var{field-name};
38900 since Guile is untyped, a predicate
38901 procedure---@code{@var{type}?}---will be called on the value
38902 corresponding to the field to ensure that the value is of the correct
38903 type. This means that if say, @var{type} is @code{package}, then a
38904 procedure named @code{package?} will be applied on the value to make
38905 sure that it is indeed a @code{<package>} object.
38907 @var{default-value} is the default value corresponding to the field; if
38908 none is specified, the user is forced to provide a value when creating
38909 an object of the record type.
38911 @c XXX: Should these be full sentences or are they allow to be very
38912 @c short like package synopses?
38913 @var{documentation} is a string formatted with Texinfo syntax which
38914 should provide a description of what setting this field does.
38916 @var{serializer} is the name of a procedure which takes two arguments,
38917 the first is the name of the field, and the second is the value
38918 corresponding to the field. The procedure should return a string or
38919 G-expression (@pxref{G-Expressions}) that represents the content that
38920 will be serialized to the configuration file. If none is specified, a
38921 procedure of the name @code{serialize-@var{type}} will be used.
38923 A simple serializer procedure could look like this:
38926 (define (serialize-boolean field-name value)
38927 (let ((value (if value "true" "false")))
38928 #~(string-append #$field-name #$value)))
38931 In some cases multiple different configuration records might be defined
38932 in the same file, but their serializers for the same type might have to
38933 be different, because they have different configuration formats. For
38934 example, the @code{serialize-boolean} procedure for the Getmail service
38935 would have to be different for the one for the Transmission service. To
38936 make it easier to deal with this situation, one can specify a serializer
38937 prefix by using the @code{prefix} literal in the
38938 @code{define-configuration} form. This means that one doesn't have to
38939 manually specify a custom @var{serializer} for every field.
38942 (define (foo-serialize-string field-name value)
38945 (define (bar-serialize-string field-name value)
38948 (define-configuration foo-configuration
38951 "The name of label.")
38954 (define-configuration bar-configuration
38957 "The IPv4 address for this device.")
38961 However, in some cases you might not want to serialize any of the values
38962 of the record, to do this, you can use the @code{no-serialization}
38963 literal. There is also the @code{define-configuration/no-serialization}
38964 macro which is a shorthand of this.
38967 ;; Nothing will be serialized to disk.
38968 (define-configuration foo-configuration
38971 "Some documentation.")
38972 (no-serialization))
38974 ;; The same thing as above.
38975 (define-configuration/no-serialization bar-configuration
38978 "Some documentation."))
38982 @deffn {Scheme Syntax} define-maybe @var{type}
38983 Sometimes a field should not be serialized if the user doesn’t specify a
38984 value. To achieve this, you can use the @code{define-maybe} macro to
38985 define a ``maybe type''; if the value of a maybe type is left unset, or
38986 is set to the @code{'unset} value, then it will not be
38989 When defining a ``maybe type'', the corresponding serializer for the
38990 regular type will be used by default. For example, a field of type
38991 @code{maybe-string} will be serialized using the @code{serialize-string}
38992 procedure by default, you can of course change this by specifying a
38993 custom serializer procedure. Likewise, the type of the value would have
38994 to be a string, or left unspecified.
38997 (define-maybe string)
38999 (define (serialize-string field-name value)
39002 (define-configuration baz-configuration
39004 ;; If set to a string, the `serialize-string' procedure will be used
39005 ;; to serialize the string. Otherwise this field is not serialized.
39006 maybe-string ; equivalent to (maybe-string *unspecified*)
39007 "The name of this module."))
39010 Like with @code{define-configuration}, one can set a prefix for the
39011 serializer name by using the @code{prefix} literal.
39014 (define-maybe integer
39017 (define (baz-serialize-interger field-name value)
39021 There is also the @code{no-serialization} literal, which when set means
39022 that no serializer will be defined for the ``maybe type'', regardless of
39023 whether its value is set or not.
39024 @code{define-maybe/no-serialization} is a shorthand for specifying the
39025 @code{no-serialization} literal.
39028 (define-maybe/no-serialization symbol)
39030 (define-configuration/no-serialization test-configuration
39037 @deffn {Scheme Procedure} serialize-configuration @var{configuration} @
39039 Return a G-expression that contains the values corresponding to the
39040 @var{fields} of @var{configuration}, a record that has been generated by
39041 @code{define-configuration}. The G-expression can then be serialized to
39042 disk by using something like @code{mixed-text-file}.
39045 @deffn {Scheme Procedure} empty-serializer @var{field-name} @var{value}
39046 A serializer that just returns an empty string. The
39047 @code{serialize-package} procedure is an alias for this.
39050 Once you have defined a configuration record, you will most likely also
39051 want to document it so that other people know to use it. To help with
39052 that, there are two procedures, both of which are documented below.
39054 @deffn {Scheme Procedure} generate-documentation @var{documentation} @
39055 @var{documentation-name}
39056 Generate a Texinfo fragment from the docstrings in @var{documentation},
39057 a list of @code{(@var{label} @var{fields} @var{sub-documentation} ...)}.
39058 @var{label} should be a symbol and should be the name of the
39059 configuration record. @var{fields} should be a list of all the fields
39060 available for the configuration record.
39062 @var{sub-documentation} is a @code{(@var{field-name}
39063 @var{configuration-name})} tuple. @var{field-name} is the name of the
39064 field which takes another configuration record as its value, and
39065 @var{configuration-name} is the name of that configuration record.
39067 @var{sub-documentation} is only needed if there are nested configuration
39068 records. For example, the @code{getmail-configuration} record
39069 (@pxref{Mail Services}) accepts a @code{getmail-configuration-file}
39070 record in one of its @code{rcfile} field, therefore documentation for
39071 @code{getmail-configuration-file} is nested in
39072 @code{getmail-configuration}.
39075 (generate-documentation
39076 `((getmail-configuration ,getmail-configuration-fields
39077 (rcfile getmail-configuration-file))
39079 'getmail-configuration)
39082 @var{documentation-name} should be a symbol and should be the name of
39083 the configuration record.
39087 @deffn {Scheme Procedure} configuration->documentation
39088 @var{configuration-symbol}
39089 Take @var{configuration-symbol}, the symbol corresponding to the name
39090 used when defining a configuration record with
39091 @code{define-configuration}, and print the Texinfo documentation of its
39092 fields. This is useful if there aren’t any nested configuration records
39093 since it only prints the documentation for the top-level fields.
39096 As of right now, there is no automated way to generate documentation for
39097 configuration records and put them in the manual. Instead, every
39098 time you make a change to the docstrings of a configuration record, you
39099 have to manually call @code{generate-documentation} or
39100 @code{configuration->documentation}, and paste the output into the
39101 @file{doc/guix.texi} file.
39103 @c TODO: Actually test this
39104 Below is an example of a record type created using
39105 @code{define-configuration} and friends.
39108 (use-modules (gnu services)
39110 (gnu services configuration)
39114 ;; Turn field names, which are Scheme symbols into strings
39115 (define (uglify-field-name field-name)
39116 (let ((str (symbol->string field-name)))
39117 ;; field? -> is-field
39118 (if (string-suffix? "?" str)
39119 (string-append "is-" (string-drop-right str 1))
39122 (define (serialize-string field-name value)
39123 #~(string-append #$(uglify-field-name field-name) " = " #$value "\n"))
39125 (define (serialize-integer field-name value)
39126 (serialize-string field-name (number->string value)))
39128 (define (serialize-boolean field-name value)
39129 (serialize-string field-name (if value "true" "false")))
39131 (define (serialize-contact-name field-name value)
39132 #~(string-append "\n[" #$value "]\n"))
39134 (define (list-of-contact-configurations? lst)
39135 (every contact-configuration? lst))
39137 (define (serialize-list-of-contact-configurations field-name value)
39138 #~(string-append #$@@(map (cut serialize-configuration <>
39139 contact-configuration-fields)
39142 (define (serialize-contacts-list-configuration configuration)
39145 #~(string-append "[Owner]\n"
39146 #$(serialize-configuration
39147 configuration contacts-list-configuration-fields))))
39149 (define-maybe integer)
39150 (define-maybe string)
39152 (define-configuration contact-configuration
39155 "The name of the contact."
39156 serialize-contact-name)
39159 "The person's phone number.")
39162 "The person's email address.")
39165 "Whether the person is married."))
39167 (define-configuration contacts-list-configuration
39170 "The name of the owner of this contact list.")
39173 "The owner's email address.")
39175 (list-of-contact-configurations '())
39176 "A list of @@code@{contact-configuation@} records which contain
39177 information about all your contacts."))
39180 A contacts list configuration could then be created like this:
39183 (define my-contacts
39184 (contacts-list-configuration
39186 (email "alice@@example.org")
39188 (list (contact-configuration
39190 (phone-number 1234)
39191 (email "bob@@gnu.org")
39193 (contact-configuration
39195 (phone-number 0000)
39199 After serializing the configuration to disk, the resulting file would
39205 email = alice@@example.org
39208 phone-number = 1234
39209 email = bob@@gnu.org
39218 @node Home Configuration
39219 @chapter Home Configuration
39220 @cindex home configuration
39221 Guix supports declarative configuration of @dfn{home environments} by
39222 utilizing the configuration mechanism described in the previous chapter
39223 (@pxref{Defining Services}), but for user's dotfiles and packages. It
39224 works both on Guix System and foreign distros and allows users to
39225 declare all the packages and services that should be installed and
39226 configured for the user. Once a user has written a file containing
39227 @code{home-environment} record, such a configuration can be
39228 @dfn{instantiated} by an unprivileged user with the @command{guix home}
39229 command (@pxref{Invoking guix home}).
39230 @c Maybe later, it will be possible to make home configuration a part of
39231 @c system configuration to make everything managed by guix system.
39234 The functionality described in this section is still under development
39235 and is subject to change. Get in touch with us on
39236 @email{guix-devel@@gnu.org}!
39239 The user's home environment usually consists of three basic parts:
39240 software, configuration, and state. Software in mainstream distros are
39241 usually installed system-wide, but with GNU Guix most software packages
39242 can be installed on a per-user basis without needing root privileges,
39243 and are thus considered part of the user’s @dfn{home environment}.
39244 Packages on their own not very useful in many cases, because often they
39245 require some additional configuration, usually config files that reside
39246 in @env{XDG_CONFIG_HOME} (@file{~/.config} by default) or other
39247 directories. Everything else can be considered state, like media files,
39248 application databases, and logs.
39250 Using Guix for managing home environments provides a number of
39255 @item All software can be configured in one language (Guile Scheme),
39256 this gives users the ability to share values between configurations of
39257 different programs.
39259 @item A well-defined home environment is self-contained and can be
39260 created in a declarative and reproducible way---there is no need to grab
39261 external binaries or manually edit some configuration file.
39263 @item After every @command{guix home reconfigure} invocation, a new home
39264 environment generation will be created. This means that users can
39265 rollback to a previous home environment generation so they don’t have to
39266 worry about breaking their configuration.
39268 @item It is possible to manage stateful data with Guix Home, this
39269 includes the ability to automatically clone Git repositories on the
39270 initial setup of the machine, and periodically running commands like
39271 @command{rsync} to sync data with another host. This functionality is
39272 still in an experimental stage, though.
39277 * Declaring the Home Environment:: Customizing your Home.
39278 * Configuring the Shell:: Enabling home environment.
39279 * Home Services:: Specifying home services.
39280 * Invoking guix home:: Instantiating a home configuration.
39283 @node Declaring the Home Environment
39284 @section Declaring the Home Environment
39285 The home environment is configured by providing a
39286 @code{home-environment} declaration in a file that can be passed to the
39287 @command{guix home} command (@pxref{Invoking guix home}). The easiest
39288 way to get started is by generating an initial configuration with
39289 @command{guix home import}:
39292 guix home import ~/src/guix-config
39295 The @command{guix home import} command reads some of the ``dot files''
39296 such as @file{~/.bashrc} found in your home directory and copies them to
39297 the given directory, @file{~/src/guix-config} in this case; it also
39298 reads the contents of your profile, @file{~/.guix-profile}, and, based
39299 on that, it populates @file{~/src/guix-config/home-configuration.scm}
39300 with a Home configuration that resembles your current configuration.
39302 A simple setup can include Bash and a custom text configuration, like in
39303 the example below. Don't be afraid to declare home environment parts,
39304 which overlaps with your current dot files: before installing any
39305 configuration files, Guix Home will back up existing config files to a
39306 separate place in the home directory.
39309 It is highly recommended that you manage your shell or shells with Guix
39310 Home, because it will make sure that all the necessary scripts are
39311 sourced by the shell configuration file. Otherwise you will need to do
39312 it manually. (@pxref{Configuring the Shell}).
39315 @findex home-environment
39317 @include he-config-bare-bones.scm
39320 The @code{packages} field should be self-explanatory, it will install
39321 the list of packages into the user's profile. The most important field
39322 is @code{services}, it contains a list of @dfn{home services}, which are
39323 the basic building blocks of a home environment.
39325 There is no daemon (at least not necessarily) related to a home service,
39326 a home service is just an element that is used to declare part of home
39327 environment and extend other parts of it. The extension mechanism
39328 discussed in the previous chapter (@pxref{Defining Services}) should not
39329 be confused with Shepherd services (@pxref{Shepherd Services}). Using this extension
39330 mechanism and some Scheme code that glues things together gives the user
39331 the freedom to declare their own, very custom, home environments.
39333 @cindex container, for @command{guix home}
39334 Once the configuration looks good, you can first test it in a throw-away
39338 guix home container config.scm
39341 The command above spawns a shell where your home environment is running.
39342 The shell runs in a container, meaning it's isolated from the rest of
39343 the system, so it's a good way to try out your configuration---you can
39344 see if configuration bits are missing or misbehaving, if daemons get
39345 started, and so on. Once you exit that shell, you're back to the prompt
39346 of your original shell ``in the real world''.
39348 Once you have a configuration file that suits your needs, you can
39349 reconfigure your home by running:
39352 guix home reconfigure config.scm
39355 This ``builds'' your home environment and creates @file{~/.guix-home}
39356 pointing to it. Voilà!
39359 Make sure the operating system has elogind, systemd, or a similar
39360 mechanism to create the XDG run-time directory and has the
39361 @env{XDG_RUNTIME_DIR} variable set. Failing that, the
39362 @file{on-first-login} script will not execute anything, and processes
39363 like user Shepherd and its descendants will not start.
39366 @node Configuring the Shell
39367 @section Configuring the Shell
39368 This section is safe to skip if your shell or shells are managed by
39369 Guix Home. Otherwise, read it carefully.
39371 There are a few scripts that must be evaluated by a login shell to
39372 activate the home environment. The shell startup files only read by
39373 login shells often have @code{profile} suffix. For more information
39374 about login shells see @ref{Invoking Bash,,, bash, The GNU Bash
39375 Reference Manual} and see @ref{Bash Startup Files,,, bash, The GNU Bash
39378 The first script that needs to be sourced is @file{setup-environment},
39379 which sets all the necessary environment variables (including variables
39380 declared by the user) and the second one is @file{on-first-login}, which
39381 starts Shepherd for the current user and performs actions declared by
39382 other home services that extends
39383 @code{home-run-on-first-login-service-type}.
39385 Guix Home will always create @file{~/.profile}, which contains the
39389 HOME_ENVIRONMENT=$HOME/.guix-home
39390 . $HOME_ENVIRONMENT/setup-environment
39391 $HOME_ENVIRONMENT/on-first-login
39394 This makes POSIX compliant login shells activate the home environment.
39395 However, in most cases this file won't be read by most modern shells,
39396 because they are run in non POSIX mode by default and have their own
39397 @file{*profile} startup files. For example Bash will prefer
39398 @file{~/.bash_profile} in case it exists and only if it doesn't will it
39399 fallback to @file{~/.profile}. Zsh (if no additional options are
39400 specified) will ignore @file{~/.profile}, even if @file{~/.zprofile}
39403 To make your shell respect @file{~/.profile}, add @code{. ~/.profile} or
39404 @code{source ~/profile} to the startup file for the login shell. In
39405 case of Bash, it is @file{~/.bash_profile}, and in case of Zsh, it is
39406 @file{~/.zprofile}.
39409 This step is only required if your shell is NOT managed by Guix Home.
39410 Otherwise, everything will be done automatically.
39413 @node Home Services
39414 @section Home Services
39415 @cindex home services
39417 A @dfn{home service} is not necessarily something that has a daemon and
39418 is managed by Shepherd (@pxref{Jump Start,,, shepherd, The GNU Shepherd
39419 Manual}), in most cases it doesn't. It's a simple building block of the
39420 home environment, often declaring a set of packages to be installed in
39421 the home environment profile, a set of config files to be symlinked into
39422 @env{XDG_CONFIG_HOME} (@file{~/.config} by default), and environment
39423 variables to be set by a login shell.
39425 There is a service extension mechanism (@pxref{Service Composition})
39426 which allows home services to extend other home services and utilize
39427 capabilities they provide; for example: declare mcron jobs
39428 (@pxref{Top,,, mcron, GNU@tie{}Mcron}) by extending @ref{Mcron Home
39429 Service}; declare daemons by extending @ref{Shepherd Home Service}; add
39430 commands, which will be invoked on by the Bash by extending
39431 @ref{Shells Home Services, @code{home-bash-service-type}}.
39433 A good way to discover available home services is using the
39434 @command{guix home search} command (@pxref{Invoking guix home}). After
39435 the required home services are found, include its module with the
39436 @code{use-modules} form (@pxref{use-modules,, Using Guile Modules,
39437 guile, The GNU Guile Reference Manual}), or the @code{#:use-modules}
39438 directive (@pxref{define-module,, Creating Guile Modules, guile, The GNU
39439 Guile Reference Manual}) and declare a home service using the
39440 @code{service} function, or extend a service type by declaring a new
39441 service with the @code{simple-service} procedure from @code{(gnu
39445 * Essential Home Services:: Environment variables, packages, on-* scripts.
39446 * Shells: Shells Home Services. POSIX shells, Bash, Zsh.
39447 * Mcron: Mcron Home Service. Scheduled User's Job Execution.
39448 * Shepherd: Shepherd Home Service. Managing User's Daemons.
39449 * SSH: Secure Shell. Setting up the secure shell client.
39450 * Desktop: Desktop Home Services. Services for graphical environments.
39451 * Guix: Guix Home Services. Services for Guix.
39453 @c In addition to that Home Services can provide
39455 @node Essential Home Services
39456 @subsection Essential Home Services
39457 There are a few essential home services defined in
39458 @code{(gnu services)}, they are mostly for internal use and are required
39459 to build a home environment, but some of them will be useful for the end
39462 @cindex environment variables
39464 @defvr {Scheme Variable} home-environment-variables-service-type
39465 The service of this type will be instantiated by every home environment
39466 automatically by default, there is no need to define it, but someone may
39467 want to extend it with a list of pairs to set some environment
39471 (list ("ENV_VAR1" . "value1")
39472 ("ENV_VAR2" . "value2"))
39475 The easiest way to extend a service type, without defining a new service
39476 type is to use the @code{simple-service} helper from @code{(gnu
39480 (simple-service 'some-useful-env-vars-service
39481 home-environment-variables-service-type
39482 `(("LESSHISTFILE" . "$XDG_CACHE_HOME/.lesshst")
39483 ("SHELL" . ,(file-append zsh "/bin/zsh"))
39484 ("USELESS_VAR" . #f)
39485 ("_JAVA_AWT_WM_NONREPARENTING" . #t)))
39488 If you include such a service in you home environment definition, it
39489 will add the following content to the @file{setup-environment} script
39490 (which is expected to be sourced by the login shell):
39493 export LESSHISTFILE=$XDG_CACHE_HOME/.lesshst
39494 export SHELL=/gnu/store/2hsg15n644f0glrcbkb1kqknmmqdar03-zsh-5.8/bin/zsh
39495 export _JAVA_AWT_WM_NONREPARENTING
39499 Make sure that module @code{(gnu packages shells)} is imported with
39500 @code{use-modules} or any other way, this namespace contains the
39501 definition of the @code{zsh} packages, which is used in the example
39505 The association list (@pxref{Association Lists, alists, Association
39506 Lists, guile, The GNU Guile Reference manual}) is a data structure
39507 containing key-value pairs, for
39508 @code{home-environment-variables-service-type} the key is always a
39509 string, the value can be a string, string-valued gexp
39510 (@pxref{G-Expressions}), file-like object (@pxref{G-Expressions,
39511 file-like object}) or boolean. For gexps, the variable will be set to
39512 the value of the gexp; for file-like objects, it will be set to the path
39513 of the file in the store (@pxref{The Store}); for @code{#t}, it will
39514 export the variable without any value; and for @code{#f}, it will omit
39519 @defvr {Scheme Variable} home-profile-service-type
39520 The service of this type will be instantiated by every home environment
39521 automatically, there is no need to define it, but you may want to extend
39522 it with a list of packages if you want to install additional packages
39523 into your profile. Other services, which need to make some programs
39524 available to the user will also extend this service type.
39526 The extension value is just a list of packages:
39529 (list htop vim emacs)
39532 The same approach as @code{simple-service} (@pxref{Service Reference,
39533 simple-service}) for @code{home-environment-variables-service-type} can
39534 be used here, too. Make sure that modules containing the specified
39535 packages are imported with @code{use-modules}. To find a package or
39536 information about its module use @command{guix search} (@pxref{Invoking
39537 guix package}). Alternatively, @code{specification->package} can be
39538 used to get the package record from string without importing related
39542 There are few more essential services, but users are not expected to
39545 @defvr {Scheme Variable} home-service-type
39546 The root of home services DAG, it generates a folder, which later will be
39547 symlinked to @file{~/.guix-home}, it contains configurations,
39548 profile with binaries and libraries, and some necessary scripts to glue
39552 @defvr {Scheme Variable} home-run-on-first-login-service-type
39553 The service of this type generates a Guile script, which is expected to
39554 be executed by the login shell. It is only executed if the special flag
39555 file inside @env{XDG_RUNTIME_DIR} hasn't been created, this prevents
39556 redundant executions of the script if multiple login shells are spawned.
39558 It can be extended with a gexp. However, to autostart an application,
39559 users @emph{should not} use this service, in most cases it's better to extend
39560 @code{home-shepherd-service-type} with a Shepherd service
39561 (@pxref{Shepherd Services}), or extend the shell's startup file with
39562 the required command using the appropriate service type.
39565 @defvr {Scheme Variable} home-activation-service-type
39566 The service of this type generates a guile script, which runs on every
39567 @command{guix home reconfigure} invocation or any other action, which
39568 leads to the activation of the home environment.
39571 @node Shells Home Services
39575 @cindex login shell
39576 @cindex interactive shell
39580 Shells play a quite important role in the environment initialization
39581 process, you can configure them manually as described in section
39582 @ref{Configuring the Shell}, but the recommended way is to use home services
39583 listed below. It's both easier and more reliable.
39585 Each home environment instantiates
39586 @code{home-shell-profile-service-type}, which creates a
39587 @file{~/.profile} startup file for all POSIX-compatible shells. This
39588 file contains all the necessary steps to properly initialize the
39589 environment, but many modern shells like Bash or Zsh prefer their own
39590 startup files, that's why the respective home services
39591 (@code{home-bash-service-type} and @code{home-zsh-service-type}) ensure
39592 that @file{~/.profile} is sourced by @file{~/.bash_profile} and
39593 @file{~/.zprofile}, respectively.
39595 @subsubheading Shell Profile Service
39597 @deftp {Data Type} home-shell-profile-configuration
39598 Available @code{home-shell-profile-configuration} fields are:
39601 @item @code{profile} (default: @code{()}) (type: text-config)
39602 @code{home-shell-profile} is instantiated automatically by
39603 @code{home-environment}, DO NOT create this service manually, it can
39604 only be extended. @code{profile} is a list of file-like objects, which
39605 will go to @file{~/.profile}. By default @file{~/.profile} contains the
39606 initialization code which must be evaluated by the login shell to make
39607 home-environment's profile available to the user, but other commands can
39608 be added to the file if it is really necessary. In most cases shell's
39609 configuration files are preferred places for user's customizations.
39610 Extend home-shell-profile service only if you really know what you do.
39616 @subsubheading Bash Home Service
39618 @anchor{home-bash-configuration}
39619 @deftp {Data Type} home-bash-configuration
39620 Available @code{home-bash-configuration} fields are:
39623 @item @code{package} (default: @code{bash}) (type: package)
39624 The Bash package to use.
39626 @item @code{guix-defaults?} (default: @code{#t}) (type: boolean)
39627 Add sane defaults like reading @file{/etc/bashrc} and coloring the output of
39628 @command{ls} to the top of the @file{.bashrc} file.
39630 @item @code{environment-variables} (default: @code{()}) (type: alist)
39631 Association list of environment variables to set for the Bash session. The
39632 rules for the @code{home-environment-variables-service-type} apply
39633 here (@pxref{Essential Home Services}). The contents of this field will be
39634 added after the contents of the @code{bash-profile} field.
39636 @item @code{aliases} (default: @code{()}) (type: alist)
39637 Association list of aliases to set for the Bash session. The aliases
39638 will be defined after the contents of the @code{bashrc} field has been
39639 put in the @file{.bashrc} file. The alias will automatically be quoted,
39640 so something line this:
39643 '(("ls" . "ls -alF"))
39652 @item @code{bash-profile} (default: @code{()}) (type: text-config)
39653 List of file-like objects, which will be added to @file{.bash_profile}.
39654 Used for executing user's commands at start of login shell (In most
39655 cases the shell started on tty just after login). @file{.bash_login}
39656 won't be ever read, because @file{.bash_profile} always present.
39658 @item @code{bashrc} (default: @code{()}) (type: text-config)
39659 List of file-like objects, which will be added to @file{.bashrc}. Used
39660 for executing user's commands at start of interactive shell (The shell
39661 for interactive usage started by typing @code{bash} or by terminal app
39662 or any other program).
39664 @item @code{bash-logout} (default: @code{()}) (type: text-config)
39665 List of file-like objects, which will be added to @file{.bash_logout}.
39666 Used for executing user's commands at the exit of login shell. It won't
39667 be read in some cases (if the shell terminates by exec'ing another
39668 process for example).
39673 You can extend the Bash service by using the @code{home-bash-extension}
39674 configuration record, whose fields most mirror that of
39675 @code{home-bash-configuration} (@pxref{home-bash-configuration}). The
39676 contents of the extensions will be added to the end of the corresponding
39677 Bash configuration files (@pxref{Bash Startup Files,,, bash, The GNU
39678 Bash Reference Manual}.
39680 For example, here is how you would define a service that extends the
39681 Bash service such that @file{~/.bash_profile} defines an additional
39682 environment variable, @env{PS1}:
39685 (define bash-fancy-prompt-service
39686 (simple-service 'bash-fancy-prompt
39687 home-bash-service-type
39688 (home-bash-extension
39689 (environment-variables
39690 '(("PS1" . "\\u \\wλ "))))))
39693 You would then add @code{bash-fancy-prompt-service} to the list in the
39694 @code{services} field of your @code{home-environment}. The reference of
39695 @code{home-bash-extension} follows.
39697 @deftp {Data Type} home-bash-extension
39698 Available @code{home-bash-extension} fields are:
39701 @item @code{environment-variables} (default: @code{()}) (type: alist)
39702 Additional environment variables to set. These will be combined with the
39703 environment variables from other extensions and the base service to form one
39704 coherent block of environment variables.
39706 @item @code{aliases} (default: @code{()}) (type: alist)
39707 Additional aliases to set. These will be combined with the aliases from
39708 other extensions and the base service.
39710 @item @code{bash-profile} (default: @code{()}) (type: text-config)
39711 Additional text blocks to add to @file{.bash_profile}, which will be combined
39712 with text blocks from other extensions and the base service.
39714 @item @code{bashrc} (default: @code{()}) (type: text-config)
39715 Additional text blocks to add to @file{.bashrc}, which will be combined
39716 with text blocks from other extensions and the base service.
39718 @item @code{bash-logout} (default: @code{()}) (type: text-config)
39719 Additional text blocks to add to @file{.bash_logout}, which will be combined
39720 with text blocks from other extensions and the base service.
39725 @subsubheading Zsh Home Service
39727 @deftp {Data Type} home-zsh-configuration
39728 Available @code{home-zsh-configuration} fields are:
39731 @item @code{package} (default: @code{zsh}) (type: package)
39732 The Zsh package to use.
39734 @item @code{xdg-flavor?} (default: @code{#t}) (type: boolean)
39735 Place all the configs to @file{$XDG_CONFIG_HOME/zsh}. Makes
39736 @file{~/.zshenv} to set @env{ZDOTDIR} to @file{$XDG_CONFIG_HOME/zsh}.
39737 Shell startup process will continue with
39738 @file{$XDG_CONFIG_HOME/zsh/.zshenv}.
39740 @item @code{environment-variables} (default: @code{()}) (type: alist)
39741 Association list of environment variables to set for the Zsh session.
39743 @item @code{zshenv} (default: @code{()}) (type: text-config)
39744 List of file-like objects, which will be added to @file{.zshenv}. Used
39745 for setting user's shell environment variables. Must not contain
39746 commands assuming the presence of tty or producing output. Will be read
39747 always. Will be read before any other file in @env{ZDOTDIR}.
39749 @item @code{zprofile} (default: @code{()}) (type: text-config)
39750 List of file-like objects, which will be added to @file{.zprofile}. Used
39751 for executing user's commands at start of login shell (In most cases the
39752 shell started on tty just after login). Will be read before
39755 @item @code{zshrc} (default: @code{()}) (type: text-config)
39756 List of file-like objects, which will be added to @file{.zshrc}. Used
39757 for executing user's commands at start of interactive shell (The shell
39758 for interactive usage started by typing @code{zsh} or by terminal app or
39759 any other program).
39761 @item @code{zlogin} (default: @code{()}) (type: text-config)
39762 List of file-like objects, which will be added to @file{.zlogin}. Used
39763 for executing user's commands at the end of starting process of login
39766 @item @code{zlogout} (default: @code{()}) (type: text-config)
39767 List of file-like objects, which will be added to @file{.zlogout}. Used
39768 for executing user's commands at the exit of login shell. It won't be
39769 read in some cases (if the shell terminates by exec'ing another process
39776 @node Mcron Home Service
39777 @subsection Scheduled User's Job Execution
39781 @cindex scheduling jobs
39783 The @code{(gnu home services mcron)} module provides an interface to
39784 GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
39785 mcron, GNU@tie{}mcron}). The information about system's mcron is
39786 applicable here (@pxref{Scheduled Job Execution}), the only difference
39787 for home services is that they have to be declared in a
39788 @code{home-environment} record instead of an @code{operating-system}
39791 @defvr {Scheme Variable} home-mcron-service-type
39792 This is the type of the @code{mcron} home service, whose value is an
39793 @code{home-mcron-configuration} object. It allows to manage scheduled
39796 This service type can be the target of a service extension that provides
39797 additional job specifications (@pxref{Service Composition}). In other
39798 words, it is possible to define services that provide additional mcron
39802 @deftp {Data Type} home-mcron-configuration
39803 Data type representing the configuration of mcron.
39806 @item @code{mcron} (default: @var{mcron})
39807 The mcron package to use.
39810 This is a list of gexps (@pxref{G-Expressions}), where each gexp
39811 corresponds to an mcron job specification (@pxref{Syntax, mcron job
39812 specifications,, mcron, GNU@tie{}mcron}).
39816 @node Shepherd Home Service
39817 @subsection Managing User Daemons
39819 @cindex shepherd services, for users
39820 The @code{(gnu home services shepherd)} module supports the definitions
39821 of per-user Shepherd services (@pxref{Introduction,,, shepherd, The GNU
39822 Shepherd Manual}). You extend @code{home-shepherd-service-type} with
39823 new services; Guix Home then takes care of starting the @code{shepherd}
39824 daemon for you when you log in, which in turns starts the services you
39827 @defvr {Scheme Variable} home-shepherd-service-type
39828 The service type for the userland Shepherd, which allows one to manage
39829 long-running processes or one-shot tasks. User's Shepherd is not an
39830 init process (PID 1), but almost all other information described in
39831 (@pxref{Shepherd Services}) is applicable here too.
39833 This is the service type that extensions target when they want to create
39834 shepherd services (@pxref{Service Types and Services}, for an example).
39835 Each extension must pass a list of @code{<shepherd-service>}. Its
39836 value must be a @code{home-shepherd-configuration}, as described below.
39839 @deftp {Data Type} home-shepherd-configuration
39840 This data type represents the Shepherd's configuration.
39843 @item shepherd (default: @code{shepherd})
39844 The Shepherd package to use.
39846 @item auto-start? (default: @code{#t})
39847 Whether or not to start Shepherd on first login.
39849 @item services (default: @code{'()})
39850 A list of @code{<shepherd-service>} to start.
39851 You should probably use the service extension
39852 mechanism instead (@pxref{Shepherd Services}).
39857 @subsection Secure Shell
39859 @cindex secure shell client, configuration
39860 @cindex SSH client, configuration
39861 The @uref{https://www.openssh.com, OpenSSH package} includes a client,
39862 the @command{ssh} command, that allows you to connect to remote machines
39863 using the @acronym{SSH, secure shell} protocol. With the @code{(gnu
39864 home services ssh)} module, you can set up OpenSSH so that it works in a
39865 predictable fashion, almost independently of state on the local machine.
39866 To do that, you instantiate @code{home-openssh-service-type} in your
39867 Home configuration, as explained below.
39869 @defvr {Scheme Variable} home-openssh-service-type
39870 This is the type of the service to set up the OpenSSH client. It takes
39871 care of several things:
39875 providing a @file{~/.ssh/config} file based on your configuration so
39876 that @command{ssh} knows about hosts you regularly connect to and their
39877 associated parameters;
39880 providing a @file{~/.ssh/authorized_keys}, which lists public keys that
39881 the local SSH server, @command{sshd}, may accept to connect to this user
39885 optionally providing a @file{~/.ssh/known_hosts} file so that @file{ssh}
39886 can authenticate hosts you connect to.
39889 Here is an example of a service and its configuration that you could add
39890 to the @code{services} field of your @code{home-environment}:
39893 (service home-openssh-service-type
39894 (home-openssh-configuration
39896 (list (openssh-host (name "ci.guix.gnu.org")
39898 (openssh-host (name "chbouib")
39899 (host-name "chbouib.example.org")
39900 (user "supercharlie")
39902 (authorized-keys (list (local-file "alice.pub")))))
39905 The example above lists two hosts and their parameters. For instance,
39906 running @command{ssh chbouib} will automatically connect to
39907 @code{chbouib.example.org} on port 10022, logging in as user
39908 @samp{supercharlie}. Further, it marks the public key in
39909 @file{alice.pub} as authorized for incoming connections.
39911 The value associated with a @code{home-openssh-service-type} instance
39912 must be a @code{home-openssh-configuration} record, as describe below.
39915 @deftp {Data Type} home-openssh-configuration
39916 This is the datatype representing the OpenSSH client and server
39917 configuration in one's home environment. It contains the following
39921 @item @code{hosts} (default: @code{'()})
39922 A list of @code{openssh-host} records specifying host names and
39923 associated connection parameters (see below). This host list goes into
39924 @file{~/.ssh/config}, which @command{ssh} reads at startup.
39926 @item @code{known-hosts} (default: @code{*unspecified*})
39927 This must be either:
39931 @code{*unspecified*}, in which case @code{home-openssh-service-type}
39932 leaves it up to @command{ssh} and to the user to maintain the list of
39933 known hosts at @file{~/.ssh/known_hosts}, or
39936 a list of file-like objects, in which case those are concatenated and
39937 emitted as @file{~/.ssh/known_hosts}.
39940 The @file{~/.ssh/known_hosts} contains a list of host name/host key
39941 pairs that allow @command{ssh} to authenticate hosts you connect to and
39942 to detect possible impersonation attacks. By default, @command{ssh}
39943 updates it in a @dfn{TOFU, trust-on-first-use} fashion, meaning that it
39944 records the host's key in that file the first time you connect to it.
39945 This behavior is preserved when @code{known-hosts} is set to
39946 @code{*unspecified*}.
39948 If you instead provide a list of host keys upfront in the
39949 @code{known-hosts} field, your configuration becomes self-contained and
39950 stateless: it can be replicated elsewhere or at another point in time.
39951 Preparing this list can be relatively tedious though, which is why
39952 @code{*unspecified*} is kept as a default.
39954 @item @code{authorized-keys} (default: @code{'()})
39955 This must be a list of file-like objects, each of which containing an
39956 SSH public key that should be authorized to connect to this machine.
39958 Concretely, these files are concatenated and made available as
39959 @file{~/.ssh/authorized_keys}. If an OpenSSH server, @command{sshd}, is
39960 running on this machine, then it @emph{may} take this file into account:
39961 this is what @command{sshd} does by default, but be aware that it can
39962 also be configured to ignore it.
39966 @c %start of fragment
39968 @deftp {Data Type} openssh-host
39969 Available @code{openssh-host} fields are:
39972 @item @code{name} (type: string)
39973 Name of this host declaration.
39975 @item @code{host-name} (type: maybe-string)
39976 Host name---e.g., @code{"foo.example.org"} or @code{"192.168.1.2"}.
39978 @item @code{address-family} (type: address-family)
39979 Address family to use when connecting to this host: one of
39980 @code{AF_INET} (for IPv4 only), @code{AF_INET6} (for IPv6 only), or
39981 @code{*unspecified*} (allowing any address family).
39983 @item @code{identity-file} (type: maybe-string)
39984 The identity file to use---e.g., @code{"/home/charlie/.ssh/id_ed25519"}.
39986 @item @code{port} (type: maybe-natural-number)
39987 TCP port number to connect to.
39989 @item @code{user} (type: maybe-string)
39990 User name on the remote host.
39992 @item @code{forward-x11?} (default: @code{#f}) (type: boolean)
39993 Whether to forward remote client connections to the local X11 graphical
39996 @item @code{forward-x11-trusted?} (default: @code{#f}) (type: boolean)
39997 Whether remote X11 clients have full access to the original X11
40000 @item @code{forward-agent?} (default: @code{#f}) (type: boolean)
40001 Whether the authentication agent (if any) is forwarded to the remote
40004 @item @code{compression?} (default: @code{#f}) (type: boolean)
40005 Whether to compress data in transit.
40007 @item @code{proxy-command} (type: maybe-string)
40008 The command to use to connect to the server. As an example, a command
40009 to connect via an HTTP proxy at 192.0.2.0 would be: @code{"nc -X connect
40010 -x 192.0.2.0:8080 %h %p"}.
40012 @item @code{host-key-algorithms} (type: maybe-string-list)
40013 The list of accepted host key algorithms---e.g.,
40014 @code{'("ssh-ed25519")}.
40016 @item @code{accepted-key-types} (type: maybe-string-list)
40017 The list of accepted user public key types.
40019 @item @code{extra-content} (default: @code{""}) (type: raw-configuration-string)
40020 Extra content appended as-is to this @code{Host} block in
40021 @file{~/.ssh/config}.
40028 @c %end of fragment
40031 @node Desktop Home Services
40032 @subsection Desktop Home Services
40034 The @code{(gnu home services desktop)} module provides services that you
40035 may find useful on ``desktop'' systems running a graphical user
40036 environment such as Xorg.
40038 @defvr {Scheme Variable} home-redshift-service-type
40039 This is the service type for @uref{https://github.com/jonls/redshift,
40040 Redshift}, a program that adjusts the display color temperature
40041 according to the time of day. Its associated value must be a
40042 @code{home-redshift-configuration} record, as shown below.
40044 A typical configuration, where we manually specify the latitude and
40045 longitude, might look like this:
40048 (service home-redshift-service-type
40049 (home-redshift-configuration
40050 (location-provider 'manual)
40051 (latitude 35.81) ;northern hemisphere
40052 (longitude -0.80))) ;west of Greenwich
40056 @deftp {Data Type} home-redshift-configuration
40057 Available @code{home-redshift-configuration} fields are:
40060 @item @code{redshift} (default: @code{redshift}) (type: file-like)
40061 Redshift package to use.
40063 @item @code{location-provider} (default: @code{geoclue2}) (type: symbol)
40064 Geolocation provider---@code{'manual} or @code{'geoclue2}. In the
40065 former case, you must also specify the @code{latitude} and
40066 @code{longitude} fields so Redshift can determine daytime at your place.
40067 In the latter case, the Geoclue system service must be running; it will
40068 be queried for location information.
40070 @item @code{adjustment-method} (default: @code{randr}) (type: symbol)
40071 Color adjustment method.
40073 @item @code{daytime-temperature} (default: @code{6500}) (type: integer)
40074 Daytime color temperature (kelvins).
40076 @item @code{nighttime-temperature} (default: @code{4500}) (type: integer)
40077 Nighttime color temperature (kelvins).
40079 @item @code{daytime-brightness} (type: maybe-inexact-number)
40080 Daytime screen brightness, between 0.1 and 1.0, or left unspecified.
40082 @item @code{nighttime-brightness} (type: maybe-inexact-number)
40083 Nighttime screen brightness, between 0.1 and 1.0, or left unspecified.
40085 @item @code{latitude} (type: maybe-inexact-number)
40086 Latitude, when @code{location-provider} is @code{'manual}.
40088 @item @code{longitude} (type: maybe-inexact-number)
40089 Longitude, when @code{location-provider} is @code{'manual}.
40091 @item @code{dawn-time} (type: maybe-string)
40092 Custom time for the transition from night to day in the
40093 morning---@code{"HH:MM"} format. When specified, solar elevation is not
40094 used to determine the daytime/nighttime period.
40096 @item @code{dusk-time} (type: maybe-string)
40097 Likewise, custom time for the transition from day to night in the
40100 @item @code{extra-content} (default: @code{""}) (type: raw-configuration-string)
40101 Extra content appended as-is to the Redshift configuration file. Run
40102 @command{man redshift} for more information about the configuration file
40109 @node Guix Home Services
40110 @subsection Guix Home Services
40112 The @code{(gnu home services guix)} module provides services for
40113 user-specific Guix configuration.
40115 @defvr {Scheme Variable} home-channels-service-type
40116 This is the service type for managing
40117 @file{$XDG_CONFIG_HOME/guix/channels.scm}, the file that controls the
40118 channels received on @command{guix pull} (@pxref{Channels}). Its
40119 associated value is a list of @code{channel} records, defined in the
40120 @code{(guix channels)} module.
40122 Generally, it is better to extend this service than to directly
40123 configure it, as its default value is the default guix channel(s)
40124 defined by @code{%default-channels}. If you configure this service
40125 directly, be sure to include a guix channel. @xref{Specifying
40126 Additional Channels} and @ref{Using a Custom Guix Channel} for more
40129 A typical extension for adding a channel might look like this:
40132 (simple-service 'variant-packages-service
40133 home-channels-service-type
40136 (name 'variant-packages)
40137 (url "https://example.org/variant-packages.git")))
40141 @node Invoking guix home
40142 @section Invoking @code{guix home}
40144 Once you have written a home environment declaration (@pxref{Declaring
40145 the Home Environment,,,,}, it can be @dfn{instantiated} using the
40146 @command{guix home} command. The synopsis is:
40149 guix home @var{options}@dots{} @var{action} @var{file}
40152 @var{file} must be the name of a file containing a
40153 @code{home-environment} declaration. @var{action} specifies how the
40154 home environment is instantiated, but there are few auxiliary actions
40155 which don't instantiate it. Currently the following values are
40160 Display available home service type definitions that match the given
40161 regular expressions, sorted by relevance:
40164 @cindex shell-profile
40168 $ guix home search shell
40169 name: home-shell-profile
40170 location: gnu/home/services/shells.scm:100:2
40171 extends: home-files
40172 description: Create `~/.profile', which is used for environment initialization of POSIX compliant login shells.
40173 + This service type can be extended with a list of file-like objects.
40177 location: gnu/home/services/shells.scm:640:2
40178 extends: home-files home-profile
40179 description: Install and configure Fish, the friendly interactive shell.
40183 location: gnu/home/services/shells.scm:290:2
40184 extends: home-files home-profile
40185 description: Install and configure Zsh.
40189 location: gnu/home/services/shells.scm:508:2
40190 extends: home-files home-profile
40191 description: Install and configure GNU Bash.
40197 As for @command{guix search}, the result is written in
40198 @code{recutils} format, which makes it easy to filter the output
40199 (@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
40201 @cindex container, for @command{guix home}
40203 Spawn a shell in an isolated environment---a
40204 @dfn{container}---containing your home as specified by @var{file}.
40206 For example, this is how you would start an interactive shell in a
40207 container with your home:
40210 guix home container config.scm
40213 This is a throw-away container where you can lightheartedly fiddle with
40214 files; any changes made within the container, any process started---all
40215 this disappears as soon as you exit that shell.
40217 As with @command{guix shell}, several options control that container:
40222 Enable networking within the container (it is disabled by default).
40224 @item --expose=@var{source}[=@var{target}]
40225 @itemx --share=@var{source}[=@var{target}]
40226 As with @command{guix shell}, make directory @var{source} of the host
40227 system available as @var{target} inside the container---read-only if you
40228 pass @option{--expose}, and writable if you pass @option{--share}
40229 (@pxref{Invoking guix shell, @option{--expose} and @option{--share}}).
40232 Additionally, you can run a command in that container, instead of
40233 spawning an interactive shell. For instance, here is how you would
40234 check which Shepherd services are started in a throw-away home
40238 guix home container config.scm -- herd status
40241 The command to run in the container must come after @code{--} (double
40244 @cindex service type definition, editing
40245 @cindex editing, service type definition
40247 Edit or view the definition of the given Home service types.
40249 For example, the command below opens your editor, as specified by the
40250 @env{EDITOR} environment variable, on the definition of the
40251 @code{home-mcron} service type:
40254 guix home edit home-mcron
40258 Build the home environment described in @var{file}, and switch to it.
40259 Switching means that the activation script will be evaluated and (in
40260 basic scenario) symlinks to configuration files generated from
40261 @code{home-environment} declaration will be created in @file{~}. If the
40262 file with the same path already exists in home folder it will be moved
40263 to @file{~/@var{timestamp}-guix-home-legacy-configs-backup}, where @var{timestamp}
40264 is a current UNIX epoch time.
40267 It is highly recommended to run @command{guix pull} once before you run
40268 @command{guix home reconfigure} for the first time (@pxref{Invoking guix
40272 This effects all the configuration specified in @var{file}. The command
40273 starts Shepherd services specified in @var{file} that are not currently
40274 running; if a service is currently running, this command will arrange
40275 for it to be upgraded the next time it is stopped (e.g.@: by @code{herd
40276 stop @var{service}} or @code{herd restart @var{service}}).
40278 This command creates a new generation whose number is one greater than
40279 the current generation (as reported by @command{guix home
40280 list-generations}). If that generation already exists, it will be
40281 overwritten. This behavior mirrors that of @command{guix package}
40282 (@pxref{Invoking guix package}).
40284 @cindex provenance tracking, of the home environment
40285 Upon completion, the new home is deployed under @file{~/.guix-home}.
40286 This directory contains @dfn{provenance meta-data}: the list of channels
40287 in use (@pxref{Channels}) and @var{file} itself, when available. You
40288 can view the provenance information by running:
40294 This information is useful should you later want to inspect how this
40295 particular generation was built. In fact, assuming @var{file} is
40296 self-contained, you can later rebuild generation @var{n} of your
40297 home environment with:
40300 guix time-machine \
40301 -C /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/channels.scm -- \
40303 /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/configuration.scm
40307 You can think of it as some sort of built-in version control! Your
40308 home is not just a binary artifact: @emph{it carries its own source}.
40309 @c @xref{Service Reference, @code{provenance-service-type}}, for more
40310 @c information on provenance tracking.
40312 @c @footnote{This action (and the related actions
40313 @c @code{switch-generation} and @code{roll-back}) are usable after the
40314 @c home environment is initialized.}.
40316 @item switch-generation
40317 @cindex home generations
40318 Switch to an existing home generation. This action atomically switches
40319 the home profile to the specified home generation.
40321 The target generation can be specified explicitly by its generation
40322 number. For example, the following invocation would switch to home
40326 guix home switch-generation 7
40329 The target generation can also be specified relative to the current
40330 generation with the form @code{+N} or @code{-N}, where @code{+3} means
40331 ``3 generations ahead of the current generation,'' and @code{-1} means
40332 ``1 generation prior to the current generation.'' When specifying a
40333 negative value such as @code{-1}, you must precede it with @code{--} to
40334 prevent it from being parsed as an option. For example:
40337 guix home switch-generation -- -1
40340 This action will fail if the specified generation does not exist.
40343 @cindex rolling back
40344 Switch to the preceding home generation. This is the inverse
40345 of @command{reconfigure}, and it is exactly the same as invoking
40346 @command{switch-generation} with an argument of @code{-1}.
40348 @item delete-generations
40349 @cindex deleting home generations
40350 @cindex saving space
40351 Delete home generations, making them candidates for garbage collection
40352 (@pxref{Invoking guix gc}, for information on how to run the ``garbage
40355 This works in the same way as @samp{guix package --delete-generations}
40356 (@pxref{Invoking guix package, @option{--delete-generations}}). With no
40357 arguments, all home generations but the current one are deleted:
40360 guix home delete-generations
40363 You can also select the generations you want to delete. The example below
40364 deletes all the home generations that are more than two months old:
40367 guix home delete-generations 2m
40371 Build the derivation of the home environment, which includes all the
40372 configuration files and programs needed. This action does not actually
40376 Describe the current home generation: its file name, as well as
40377 provenance information when available.
40379 To show installed packages in the current home generation's profile, the
40380 @code{--list-installed} flag is provided, with the same syntax that is
40381 used in @command{guix package --list-installed} (@pxref{Invoking guix
40382 package}). For instance, the following command shows a table of all the
40383 packages with ``emacs'' in their name that are installed in the current
40384 home generation's profile:
40387 guix home describe --list-installed=emacs
40390 @item list-generations
40391 List a summary of each generation of the home environment available on
40392 disk, in a human-readable way. This is similar to the
40393 @option{--list-generations} option of @command{guix package}
40394 (@pxref{Invoking guix package}).
40396 Optionally, one can specify a pattern, with the same syntax that is used
40397 in @command{guix package --list-generations}, to restrict the list of
40398 generations displayed. For instance, the following command displays
40399 generations that are up to 10 days old:
40402 guix home list-generations 10d
40405 The @code{--list-installed} flag may also be specified, with the same
40406 syntax that is used in @command{guix home describe}. This may be
40407 helpful if trying to determine when a package was added to the home
40411 Generate a @dfn{home environment} from the packages in the default
40412 profile and configuration files found in the user's home directory. The
40413 configuration files will be copied to the specified directory, and a
40414 @file{home-configuration.scm} will be populated with the home
40415 environment. Note that not every home service that exists is supported
40416 (@pxref{Home Services}).
40419 $ guix home import ~/guix-config
40420 guix home: '/home/alice/guix-config' populated with all the Home configuration files
40424 And there's more! @command{guix home} also provides the following
40425 sub-commands to visualize how the services of your home environment
40426 relate to one another:
40429 @cindex service extension graph, of a home environment
40430 @item extension-graph
40431 Emit to standard output the @dfn{service extension graph} of the home
40432 environment defined in @var{file} (@pxref{Service Composition}, for more
40433 information on service extensions). By default the output is in
40434 Dot/Graphviz format, but you can choose a different format with
40435 @option{--graph-backend}, as with @command{guix graph} (@pxref{Invoking
40436 guix graph, @option{--backend}}):
40441 guix home extension-graph @var{file} | xdot -
40444 shows the extension relations among services.
40446 @cindex Shepherd dependency graph, for a home environment
40447 @item shepherd-graph
40448 Emit to standard output the @dfn{dependency graph} of shepherd services
40449 of the home environment defined in @var{file}. @xref{Shepherd
40450 Services}, for more information and for an example graph.
40452 Again, the default output format is Dot/Graphviz, but you can pass
40453 @option{--graph-backend} to select a different one.
40456 @var{options} can contain any of the common build options (@pxref{Common
40457 Build Options}). In addition, @var{options} can contain one of the
40462 @item --expression=@var{expr}
40463 @itemx -e @var{expr}
40464 Consider the home-environment @var{expr} evaluates to.
40465 This is an alternative to specifying a file which evaluates to a home
40468 @item --allow-downgrades
40469 Instruct @command{guix home reconfigure} to allow system downgrades.
40471 Just like @command{guix system}, @command{guix home reconfigure}, by
40472 default, prevents you from downgrading your home to older or unrelated
40473 revisions compared to the channel revisions that were used to deploy
40474 it---those shown by @command{guix home describe}. Using
40475 @option{--allow-downgrades} allows you to bypass that check, at the risk
40476 of downgrading your home---be careful!
40480 @node Documentation
40481 @chapter Documentation
40483 @cindex documentation, searching for
40484 @cindex searching for documentation
40485 @cindex Info, documentation format
40487 @cindex manual pages
40488 In most cases packages installed with Guix come with documentation.
40489 There are two main documentation formats: ``Info'', a browsable
40490 hypertext format used for GNU software, and ``manual pages'' (or ``man
40491 pages''), the linear documentation format traditionally found on Unix.
40492 Info manuals are accessed with the @command{info} command or with Emacs,
40493 and man pages are accessed using @command{man}.
40495 You can look for documentation of software installed on your system by
40496 keyword. For example, the following command searches for information
40497 about ``TLS'' in Info manuals:
40501 "(emacs)Network Security" -- STARTTLS
40502 "(emacs)Network Security" -- TLS
40503 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_flags
40504 "(gnutls)Core TLS API" -- gnutls_certificate_set_verify_function
40509 The command below searches for the same keyword in man
40510 pages@footnote{The database searched by @command{man -k} is only created
40511 in profiles that contain the @code{man-db} package.}:
40515 SSL (7) - OpenSSL SSL/TLS library
40516 certtool (1) - GnuTLS certificate tool
40520 These searches are purely local to your computer so you have the
40521 guarantee that documentation you find corresponds to what you have
40522 actually installed, you can access it off-line, and your privacy is
40525 Once you have these results, you can view the relevant documentation by
40529 $ info "(gnutls)Core TLS API"
40539 Info manuals contain sections and indices as well as hyperlinks like
40540 those found in Web pages. The @command{info} reader (@pxref{Top, Info
40541 reader,, info-stnd, Stand-alone GNU Info}) and its Emacs counterpart
40542 (@pxref{Misc Help,,, emacs, The GNU Emacs Manual}) provide intuitive key
40543 bindings to navigate manuals. @xref{Getting Started,,, info, Info: An
40544 Introduction}, for an introduction to Info navigation.
40546 @node Installing Debugging Files
40547 @chapter Installing Debugging Files
40549 @cindex debugging files
40550 Program binaries, as produced by the GCC compilers for instance, are
40551 typically written in the ELF format, with a section containing
40552 @dfn{debugging information}. Debugging information is what allows the
40553 debugger, GDB, to map binary code to source code; it is required to
40554 debug a compiled program in good conditions.
40556 This chapter explains how to use separate debug info when packages
40557 provide it, and how to rebuild packages with debug info when it's
40561 * Separate Debug Info:: Installing 'debug' outputs.
40562 * Rebuilding Debug Info:: Building missing debug info.
40565 @node Separate Debug Info
40566 @section Separate Debug Info
40568 The problem with debugging information is that is takes up a fair amount
40569 of disk space. For example, debugging information for the GNU C Library
40570 weighs in at more than 60 MiB@. Thus, as a user, keeping all the
40571 debugging info of all the installed programs is usually not an option.
40572 Yet, space savings should not come at the cost of an impediment to
40573 debugging---especially in the GNU system, which should make it easier
40574 for users to exert their computing freedom (@pxref{GNU Distribution}).
40576 Thankfully, the GNU Binary Utilities (Binutils) and GDB provide a
40577 mechanism that allows users to get the best of both worlds: debugging
40578 information can be stripped from the binaries and stored in separate
40579 files. GDB is then able to load debugging information from those files,
40580 when they are available (@pxref{Separate Debug Files,,, gdb, Debugging
40583 The GNU distribution takes advantage of this by storing debugging
40584 information in the @code{lib/debug} sub-directory of a separate package
40585 output unimaginatively called @code{debug} (@pxref{Packages with
40586 Multiple Outputs}). Users can choose to install the @code{debug} output
40587 of a package when they need it. For instance, the following command
40588 installs the debugging information for the GNU C Library and for GNU
40592 guix install glibc:debug guile:debug
40595 GDB must then be told to look for debug files in the user's profile, by
40596 setting the @code{debug-file-directory} variable (consider setting it
40597 from the @file{~/.gdbinit} file, @pxref{Startup,,, gdb, Debugging with
40601 (gdb) set debug-file-directory ~/.guix-profile/lib/debug
40604 From there on, GDB will pick up debugging information from the
40605 @file{.debug} files under @file{~/.guix-profile/lib/debug}.
40607 Below is an alternative GDB script which is useful when working with
40608 other profiles. It takes advantage of the optional Guile integration in
40609 GDB. This snippet is included by default on Guix System in the
40610 @file{~/.gdbinit} file.
40614 (use-modules (gdb))
40615 (execute (string-append "set debug-file-directory "
40616 (or (getenv "GDB_DEBUG_FILE_DIRECTORY")
40617 "~/.guix-profile/lib/debug")))
40621 In addition, you will most likely want GDB to be able to show the source
40622 code being debugged. To do that, you will have to unpack the source
40623 code of the package of interest (obtained with @code{guix build
40624 --source}, @pxref{Invoking guix build}), and to point GDB to that source
40625 directory using the @code{directory} command (@pxref{Source Path,
40626 @code{directory},, gdb, Debugging with GDB}).
40628 @c XXX: keep me up-to-date
40629 The @code{debug} output mechanism in Guix is implemented by the
40630 @code{gnu-build-system} (@pxref{Build Systems}). Currently, it is
40631 opt-in---debugging information is available only for the packages with
40632 definitions explicitly declaring a @code{debug} output. To check
40633 whether a package has a @code{debug} output, use @command{guix package
40634 --list-available} (@pxref{Invoking guix package}).
40636 Read on for how to deal with packages lacking a @code{debug} output.
40638 @node Rebuilding Debug Info
40639 @section Rebuilding Debug Info
40641 @cindex debugging info, rebuilding
40642 As we saw above, some packages, but not all, provide debugging info in a
40643 @code{debug} output. What can you do when debugging info is missing?
40644 The @option{--with-debug-info} option provides a solution to that: it
40645 allows you to rebuild the package(s) for which debugging info is
40646 missing---and only those---and to graft those onto the application
40647 you're debugging. Thus, while it's not as fast as installing a
40648 @code{debug} output, it is relatively inexpensive.
40650 Let's illustrate that. Suppose you're experiencing a bug in Inkscape
40651 and would like to see what's going on in GLib, a library that's deep
40652 down in its dependency graph. As it turns out, GLib does not have a
40653 @code{debug} output and the backtrace GDB shows is all sadness:
40657 #0 0x00007ffff5f92190 in g_getenv ()
40658 from /gnu/store/@dots{}-glib-2.62.6/lib/libglib-2.0.so.0
40659 #1 0x00007ffff608a7d6 in gobject_init_ctor ()
40660 from /gnu/store/@dots{}-glib-2.62.6/lib/libgobject-2.0.so.0
40661 #2 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=1, argv=argv@@entry=0x7fffffffcfd8,
40662 env=env@@entry=0x7fffffffcfe8) at dl-init.c:72
40663 #3 0x00007ffff7fe2866 in call_init (env=0x7fffffffcfe8, argv=0x7fffffffcfd8, argc=1, l=<optimized out>)
40667 To address that, you install Inkscape linked against a variant GLib that
40668 contains debug info:
40671 guix install inkscape --with-debug-info=glib
40674 This time, debugging will be a whole lot nicer:
40677 $ gdb --args sh -c 'exec inkscape'
40680 Function "g_getenv" not defined.
40681 Make breakpoint pending on future shared library load? (y or [n]) y
40682 Breakpoint 1 (g_getenv) pending.
40684 Starting program: /gnu/store/@dots{}-profile/bin/sh -c exec\ inkscape
40687 #0 g_getenv (variable=variable@@entry=0x7ffff60c7a2e "GOBJECT_DEBUG") at ../glib-2.62.6/glib/genviron.c:252
40688 #1 0x00007ffff608a7d6 in gobject_init () at ../glib-2.62.6/gobject/gtype.c:4380
40689 #2 gobject_init_ctor () at ../glib-2.62.6/gobject/gtype.c:4493
40690 #3 0x00007ffff7fe275a in call_init (l=<optimized out>, argc=argc@@entry=3, argv=argv@@entry=0x7fffffffd088,
40691 env=env@@entry=0x7fffffffd0a8) at dl-init.c:72
40697 Note that there can be packages for which @option{--with-debug-info}
40698 will not have the desired effect. @xref{Package Transformation Options,
40699 @option{--with-debug-info}}, for more information.
40701 @node Using TeX and LaTeX
40702 @chapter Using @TeX{} and @LaTeX{}
40704 @cindex @TeX{} packages
40705 @cindex @LaTeX{} packages
40706 Guix provides packages for the @TeX{}, @LaTeX{}, ConTeXt, LuaTeX, and
40707 related typesetting systems, taken from the
40708 @uref{https://www.tug.org/texlive/, @TeX{} Live distribution}. However,
40709 because @TeX{} Live is so huge and because finding your way in this maze
40710 is tricky, we thought that you, dear user, would welcome guidance on how
40711 to deploy the relevant packages so you can compile your @TeX{} and
40712 @LaTeX{} documents.
40714 @TeX{} Live currently comes in two flavors in Guix:
40718 The ``monolithic'' @code{texlive} package: it comes with @emph{every
40719 single @TeX{} Live package} (more than 7,000 of them), but it is huge
40720 (more than 4@tie{}GiB for a single package!).
40723 The ``modular'' @code{texlive-} packages: you install
40724 @code{texlive-base}, which provides core functionality and the main
40725 commands---@command{pdflatex}, @command{dvips}, @command{luatex},
40726 @command{mf}, etc.---together with individual packages that provide just
40727 the features you need---@code{texlive-listings} for the
40728 @code{listings} package, @code{texlive-hyperref} for @code{hyperref},
40729 @code{texlive-beamer} for Beamer, @code{texlive-pgf} for PGF/TikZ,
40733 We recommend using the modular package set because it is much less
40734 resource-hungry. To build your documents, you would use commands such
40738 guix shell texlive-base texlive-wrapfig \
40739 texlive-hyperref texlive-cm-super -- pdflatex doc.tex
40742 You can quickly end up with unreasonably long command lines though. The
40743 solution is to instead write a manifest, for example like this one:
40746 (specifications->manifest
40752 "texlive-microtype"
40753 "texlive-listings" "texlive-hyperref"
40758 ;; Additional fonts.
40759 "texlive-cm-super" "texlive-amsfonts"
40760 "texlive-times" "texlive-helvetic" "texlive-courier"))
40763 You can then pass it to any command with the @option{-m} option:
40766 guix shell -m manifest.scm -- pdflatex doc.tex
40769 @xref{Writing Manifests}, for more on
40770 manifests. In the future, we plan to provide packages for @TeX{} Live
40771 @dfn{collections}---``meta-packages'' such as @code{fontsrecommended},
40772 @code{humanities}, or @code{langarabic} that provide the set of packages
40773 needed in this particular domain. That will allow you to list fewer
40776 The main difficulty here is that using the modular package set forces
40777 you to select precisely the packages that you need. You can use
40778 @command{guix search}, but finding the right package can prove to be
40779 tedious. When a package is missing, @command{pdflatex} and similar
40780 commands fail with an obscure message along the lines of:
40783 doc.tex: File `tikz.sty' not found.
40784 doc.tex:7: Emergency stop.
40788 or, for a missing font:
40791 kpathsea: Running mktexmf phvr7t
40792 ! I can't find file `phvr7t'.
40795 How do you determine what the missing package is? In the first case,
40796 you'll find the answer by running:
40799 $ guix search texlive tikz
40805 In the second case, @command{guix search} turns up nothing. Instead,
40806 you can search the @TeX{} Live package database using the @command{tlmgr}
40810 $ guix shell texlive-base -- tlmgr info phvr7t
40811 tlmgr: cannot find package phvr7t, searching for other matches:
40813 Packages containing `phvr7t' in their title/description:
40815 Packages containing files matching `phvr7t':
40817 texmf-dist/fonts/tfm/adobe/helvetic/phvr7t.tfm
40818 texmf-dist/fonts/tfm/adobe/helvetic/phvr7tn.tfm
40819 texmf-dist/fonts/vf/adobe/helvetic/phvr7t.vf
40820 texmf-dist/fonts/vf/adobe/helvetic/phvr7tn.vf
40822 texmf-dist/tex4ht/ht-fonts/alias/adobe/helvetic/phvr7t.htf
40825 The file is available in the @TeX{} Live @code{helvetic} package, which is
40826 known in Guix as @code{texlive-helvetic}. Quite a ride, but we found
40829 There is one important limitation though: Guix currently provides a
40830 subset of the @TeX{} Live packages. If you stumble upon a missing
40831 package, you can try and import it (@pxref{Invoking guix import}):
40834 guix import texlive @var{package}
40837 Additional options include:
40842 Traverse the dependency graph of the given upstream package recursively
40843 and generate package expressions for all those packages that are not yet
40848 @TeX{} Live packaging is still very much work in progress, but you can
40849 help! @xref{Contributing}, for more information.
40852 @node Security Updates
40853 @chapter Security Updates
40855 @cindex security updates
40856 @cindex security vulnerabilities
40857 Occasionally, important security vulnerabilities are discovered in software
40858 packages and must be patched. Guix developers try hard to keep track of
40859 known vulnerabilities and to apply fixes as soon as possible in the
40860 @code{master} branch of Guix (we do not yet provide a ``stable'' branch
40861 containing only security updates). The @command{guix lint} tool helps
40862 developers find out about vulnerable versions of software packages in the
40867 gnu/packages/base.scm:652:2: glibc@@2.21: probably vulnerable to CVE-2015-1781, CVE-2015-7547
40868 gnu/packages/gcc.scm:334:2: gcc@@4.9.3: probably vulnerable to CVE-2015-5276
40869 gnu/packages/image.scm:312:2: openjpeg@@2.1.0: probably vulnerable to CVE-2016-1923, CVE-2016-1924
40873 @xref{Invoking guix lint}, for more information.
40875 Guix follows a functional
40876 package management discipline (@pxref{Introduction}), which implies
40877 that, when a package is changed, @emph{every package that depends on it}
40878 must be rebuilt. This can significantly slow down the deployment of
40879 fixes in core packages such as libc or Bash, since basically the whole
40880 distribution would need to be rebuilt. Using pre-built binaries helps
40881 (@pxref{Substitutes}), but deployment may still take more time than
40885 To address this, Guix implements @dfn{grafts}, a mechanism that allows
40886 for fast deployment of critical updates without the costs associated
40887 with a whole-distribution rebuild. The idea is to rebuild only the
40888 package that needs to be patched, and then to ``graft'' it onto packages
40889 explicitly installed by the user and that were previously referring to
40890 the original package. The cost of grafting is typically very low, and
40891 order of magnitudes lower than a full rebuild of the dependency chain.
40893 @cindex replacements of packages, for grafts
40894 For instance, suppose a security update needs to be applied to Bash.
40895 Guix developers will provide a package definition for the ``fixed''
40896 Bash, say @code{bash-fixed}, in the usual way (@pxref{Defining
40897 Packages}). Then, the original package definition is augmented with a
40898 @code{replacement} field pointing to the package containing the bug fix:
40905 (replacement bash-fixed)))
40908 From there on, any package depending directly or indirectly on Bash---as
40909 reported by @command{guix gc --requisites} (@pxref{Invoking guix
40910 gc})---that is installed is automatically ``rewritten'' to refer to
40911 @code{bash-fixed} instead of @code{bash}. This grafting process takes
40912 time proportional to the size of the package, usually less than a
40913 minute for an ``average'' package on a recent machine. Grafting is
40914 recursive: when an indirect dependency requires grafting, then grafting
40915 ``propagates'' up to the package that the user is installing.
40917 Currently, the length of the name and version of the graft and that of
40918 the package it replaces (@code{bash-fixed} and @code{bash} in the example
40919 above) must be equal. This restriction mostly comes from the fact that
40920 grafting works by patching files, including binary files, directly.
40921 Other restrictions may apply: for instance, when adding a graft to a
40922 package providing a shared library, the original shared library and its
40923 replacement must have the same @code{SONAME} and be binary-compatible.
40925 The @option{--no-grafts} command-line option allows you to forcefully
40926 avoid grafting (@pxref{Common Build Options, @option{--no-grafts}}).
40930 guix build bash --no-grafts
40934 returns the store file name of the original Bash, whereas:
40941 returns the store file name of the ``fixed'', replacement Bash. This
40942 allows you to distinguish between the two variants of Bash.
40944 To verify which Bash your whole profile refers to, you can run
40945 (@pxref{Invoking guix gc}):
40948 guix gc -R $(readlink -f ~/.guix-profile) | grep bash
40952 @dots{} and compare the store file names that you get with those above.
40953 Likewise for a complete Guix system generation:
40956 guix gc -R $(guix system build my-config.scm) | grep bash
40959 Lastly, to check which Bash running processes are using, you can use the
40960 @command{lsof} command:
40963 lsof | grep /gnu/store/.*bash
40967 @node Bootstrapping
40968 @chapter Bootstrapping
40970 @c Adapted from the ELS 2013 paper.
40972 @cindex bootstrapping
40974 Bootstrapping in our context refers to how the distribution gets built
40975 ``from nothing''. Remember that the build environment of a derivation
40976 contains nothing but its declared inputs (@pxref{Introduction}). So
40977 there's an obvious chicken-and-egg problem: how does the first package
40978 get built? How does the first compiler get compiled?
40980 It is tempting to think of this question as one that only die-hard
40981 hackers may care about. However, while the answer to that question is
40982 technical in nature, its implications are wide-ranging. How the
40983 distribution is bootstrapped defines the extent to which we, as
40984 individuals and as a collective of users and hackers, can trust the
40985 software we run. It is a central concern from the standpoint of
40986 @emph{security} and from a @emph{user freedom} viewpoint.
40988 @cindex bootstrap binaries
40989 The GNU system is primarily made of C code, with libc at its core. The
40990 GNU build system itself assumes the availability of a Bourne shell and
40991 command-line tools provided by GNU Coreutils, Awk, Findutils, `sed', and
40992 `grep'. Furthermore, build programs---programs that run
40993 @code{./configure}, @code{make}, etc.---are written in Guile Scheme
40994 (@pxref{Derivations}). Consequently, to be able to build anything at
40995 all, from scratch, Guix relies on pre-built binaries of Guile, GCC,
40996 Binutils, libc, and the other packages mentioned above---the
40997 @dfn{bootstrap binaries}.
40999 These bootstrap binaries are ``taken for granted'', though we can also
41000 re-create them if needed (@pxref{Preparing to Use the Bootstrap
41004 * Reduced Binary Seed Bootstrap:: A Bootstrap worthy of GNU.
41005 * Preparing to Use the Bootstrap Binaries:: Building that what matters most.
41008 @node Reduced Binary Seed Bootstrap
41009 @section The Reduced Binary Seed Bootstrap
41011 Guix---like other GNU/Linux distributions---is traditionally bootstrapped from
41012 a set of bootstrap binaries: Bourne shell, command-line tools provided by GNU
41013 Coreutils, Awk, Findutils, `sed', and `grep' and Guile, GCC, Binutils, and the
41014 GNU C Library (@pxref{Bootstrapping}). Usually, these bootstrap binaries are
41015 ``taken for granted.''
41017 Taking the bootstrap binaries for granted means that we consider them to
41018 be a correct and trustworthy ``seed'' for building the complete system.
41019 Therein lies a problem: the combined size of these bootstrap binaries is
41020 about 250MB (@pxref{Bootstrappable Builds,,, mes, GNU Mes}). Auditing
41021 or even inspecting these is next to impossible.
41023 For @code{i686-linux} and @code{x86_64-linux}, Guix now features a
41024 ``Reduced Binary Seed'' bootstrap @footnote{We would like to say: ``Full
41025 Source Bootstrap'' and while we are working towards that goal it would
41026 be hyperbole to use that term for what we do now.}.
41028 The Reduced Binary Seed bootstrap removes the most critical tools---from a
41029 trust perspective---from the bootstrap binaries: GCC, Binutils and the GNU C
41030 Library are replaced by: @code{bootstrap-mescc-tools} (a tiny assembler and
41031 linker) and @code{bootstrap-mes} (a small Scheme Interpreter and a C compiler
41032 written in Scheme and the Mes C Library, built for TinyCC and for GCC).
41034 Using these new binary seeds the ``missing'' Binutils, GCC, and the GNU
41035 C Library are built from source. From here on the more traditional
41036 bootstrap process resumes. This approach has reduced the bootstrap
41037 binaries in size to about 145MB in Guix v1.1.
41039 The next step that Guix has taken is to replace the shell and all its
41040 utilities with implementations in Guile Scheme, the @emph{Scheme-only
41041 bootstrap}. Gash (@pxref{Gash,,, gash, The Gash manual}) is a
41042 POSIX-compatible shell that replaces Bash, and it comes with Gash Utils
41043 which has minimalist replacements for Awk, the GNU Core Utilities, Grep,
41044 Gzip, Sed, and Tar. The rest of the bootstrap binary seeds that were
41045 removed are now built from source.
41047 Building the GNU System from source is currently only possible by adding
41048 some historical GNU packages as intermediate steps@footnote{Packages
41049 such as @code{gcc-2.95.3}, @code{binutils-2.14}, @code{glibc-2.2.5},
41050 @code{gzip-1.2.4}, @code{tar-1.22}, and some others. For details, see
41051 @file{gnu/packages/commencement.scm}.}. As Gash and Gash Utils mature,
41052 and GNU packages become more bootstrappable again (e.g., new releases of
41053 GNU Sed will also ship as gzipped tarballs again, as alternative to the
41054 hard to bootstrap @code{xz}-compression), this set of added packages can
41055 hopefully be reduced again.
41057 The graph below shows the resulting dependency graph for
41058 @code{gcc-core-mesboot0}, the bootstrap compiler used for the
41059 traditional bootstrap of the rest of the Guix System.
41061 @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
41062 @image{images/gcc-core-mesboot0-graph,6in,,Dependency graph of gcc-core-mesboot0}
41064 The only significant binary bootstrap seeds that remain@footnote{
41065 Ignoring the 68KB @code{mescc-tools}; that will be removed later,
41066 together with @code{mes}.} are a Scheme interpreter and a Scheme
41067 compiler: GNU Mes and GNU Guile@footnote{Not shown in this graph are the
41068 static binaries for @file{bash}, @code{tar}, and @code{xz} that are used
41069 to get Guile running.}.
41071 This further reduction has brought down the size of the binary seed to
41072 about 60MB for @code{i686-linux} and @code{x86_64-linux}.
41074 Work is ongoing to remove all binary blobs from our free software
41075 bootstrap stack, working towards a Full Source Bootstrap. Also ongoing
41076 is work to bring these bootstraps to the @code{arm-linux} and
41077 @code{aarch64-linux} architectures and to the Hurd.
41079 If you are interested, join us on @samp{#bootstrappable} on the Freenode
41080 IRC network or discuss on @email{bug-mes@@gnu.org} or
41081 @email{gash-devel@@nongnu.org}.
41083 @node Preparing to Use the Bootstrap Binaries
41084 @section Preparing to Use the Bootstrap Binaries
41086 @c As of Emacs 24.3, Info-mode displays the image, but since it's a
41087 @c large image, it's hard to scroll. Oh well.
41088 @image{images/bootstrap-graph,6in,,Dependency graph of the early bootstrap derivations}
41090 The figure above shows the very beginning of the dependency graph of the
41091 distribution, corresponding to the package definitions of the @code{(gnu
41092 packages bootstrap)} module. A similar figure can be generated with
41093 @command{guix graph} (@pxref{Invoking guix graph}), along the lines of:
41096 guix graph -t derivation \
41097 -e '(@@@@ (gnu packages bootstrap) %bootstrap-gcc)' \
41098 | dot -Tps > gcc.ps
41101 or, for the further Reduced Binary Seed bootstrap
41104 guix graph -t derivation \
41105 -e '(@@@@ (gnu packages bootstrap) %bootstrap-mes)' \
41106 | dot -Tps > mes.ps
41109 At this level of detail, things are
41110 slightly complex. First, Guile itself consists of an ELF executable,
41111 along with many source and compiled Scheme files that are dynamically
41112 loaded when it runs. This gets stored in the @file{guile-2.0.7.tar.xz}
41113 tarball shown in this graph. This tarball is part of Guix's ``source''
41114 distribution, and gets inserted into the store with @code{add-to-store}
41115 (@pxref{The Store}).
41117 But how do we write a derivation that unpacks this tarball and adds it
41118 to the store? To solve this problem, the @code{guile-bootstrap-2.0.drv}
41119 derivation---the first one that gets built---uses @code{bash} as its
41120 builder, which runs @code{build-bootstrap-guile.sh}, which in turn calls
41121 @code{tar} to unpack the tarball. Thus, @file{bash}, @file{tar},
41122 @file{xz}, and @file{mkdir} are statically-linked binaries, also part of
41123 the Guix source distribution, whose sole purpose is to allow the Guile
41124 tarball to be unpacked.
41126 Once @code{guile-bootstrap-2.0.drv} is built, we have a functioning
41127 Guile that can be used to run subsequent build programs. Its first task
41128 is to download tarballs containing the other pre-built binaries---this
41129 is what the @file{.tar.xz.drv} derivations do. Guix modules such as
41130 @code{ftp-client.scm} are used for this purpose. The
41131 @code{module-import.drv} derivations import those modules in a directory
41132 in the store, using the original layout. The
41133 @code{module-import-compiled.drv} derivations compile those modules, and
41134 write them in an output directory with the right layout. This
41135 corresponds to the @code{#:modules} argument of
41136 @code{build-expression->derivation} (@pxref{Derivations}).
41138 Finally, the various tarballs are unpacked by the derivations
41139 @code{gcc-bootstrap-0.drv}, @code{glibc-bootstrap-0.drv}, or
41140 @code{bootstrap-mes-0.drv} and @code{bootstrap-mescc-tools-0.drv}, at which
41141 point we have a working C tool chain.
41143 @unnumberedsec Building the Build Tools
41145 Bootstrapping is complete when we have a full tool chain that does not
41146 depend on the pre-built bootstrap tools discussed above. This
41147 no-dependency requirement is verified by checking whether the files of
41148 the final tool chain contain references to the @file{/gnu/store}
41149 directories of the bootstrap inputs. The process that leads to this
41150 ``final'' tool chain is described by the package definitions found in
41151 the @code{(gnu packages commencement)} module.
41153 The @command{guix graph} command allows us to ``zoom out'' compared to
41154 the graph above, by looking at the level of package objects instead of
41155 individual derivations---remember that a package may translate to
41156 several derivations, typically one derivation to download its source,
41157 one to build the Guile modules it needs, and one to actually build the
41158 package from source. The command:
41161 guix graph -t bag \
41162 -e '(@@@@ (gnu packages commencement)
41163 glibc-final-with-bootstrap-bash)' | xdot -
41167 displays the dependency graph leading to the ``final'' C
41168 library@footnote{You may notice the @code{glibc-intermediate} label,
41169 suggesting that it is not @emph{quite} final, but as a good
41170 approximation, we will consider it final.}, depicted below.
41172 @image{images/bootstrap-packages,6in,,Dependency graph of the early packages}
41174 @c See <https://lists.gnu.org/archive/html/gnu-system-discuss/2012-10/msg00000.html>.
41175 The first tool that gets built with the bootstrap binaries is
41176 GNU@tie{}Make---noted @code{make-boot0} above---which is a prerequisite
41177 for all the following packages. From there Findutils and Diffutils get
41180 Then come the first-stage Binutils and GCC, built as pseudo cross
41181 tools---i.e., with @option{--target} equal to @option{--host}. They are
41182 used to build libc. Thanks to this cross-build trick, this libc is
41183 guaranteed not to hold any reference to the initial tool chain.
41185 From there the final Binutils and GCC (not shown above) are built. GCC
41186 uses @command{ld} from the final Binutils, and links programs against
41187 the just-built libc. This tool chain is used to build the other
41188 packages used by Guix and by the GNU Build System: Guile, Bash,
41191 And voilà! At this point we have the complete set of build tools that
41192 the GNU Build System expects. These are in the @code{%final-inputs}
41193 variable of the @code{(gnu packages commencement)} module, and are
41194 implicitly used by any package that uses @code{gnu-build-system}
41195 (@pxref{Build Systems, @code{gnu-build-system}}).
41198 @unnumberedsec Building the Bootstrap Binaries
41200 @cindex bootstrap binaries
41201 Because the final tool chain does not depend on the bootstrap binaries,
41202 those rarely need to be updated. Nevertheless, it is useful to have an
41203 automated way to produce them, should an update occur, and this is what
41204 the @code{(gnu packages make-bootstrap)} module provides.
41206 The following command builds the tarballs containing the bootstrap binaries
41207 (Binutils, GCC, glibc, for the traditional bootstrap and linux-libre-headers,
41208 bootstrap-mescc-tools, bootstrap-mes for the Reduced Binary Seed bootstrap,
41209 and Guile, and a tarball containing a mixture of Coreutils and other basic
41210 command-line tools):
41213 guix build bootstrap-tarballs
41216 The generated tarballs are those that should be referred to in the
41217 @code{(gnu packages bootstrap)} module mentioned at the beginning of
41220 Still here? Then perhaps by now you've started to wonder: when do we
41221 reach a fixed point? That is an interesting question! The answer is
41222 unknown, but if you would like to investigate further (and have
41223 significant computational and storage resources to do so), then let us
41226 @unnumberedsec Reducing the Set of Bootstrap Binaries
41228 Our traditional bootstrap includes GCC, GNU Libc, Guile, etc. That's a lot of
41229 binary code! Why is that a problem? It's a problem because these big chunks
41230 of binary code are practically non-auditable, which makes it hard to establish
41231 what source code produced them. Every unauditable binary also leaves us
41232 vulnerable to compiler backdoors as described by Ken Thompson in the 1984
41233 paper @emph{Reflections on Trusting Trust}.
41235 This is mitigated by the fact that our bootstrap binaries were generated
41236 from an earlier Guix revision. Nevertheless it lacks the level of
41237 transparency that we get in the rest of the package dependency graph,
41238 where Guix always gives us a source-to-binary mapping. Thus, our goal
41239 is to reduce the set of bootstrap binaries to the bare minimum.
41241 The @uref{https://bootstrappable.org, Bootstrappable.org web site} lists
41242 on-going projects to do that. One of these is about replacing the
41243 bootstrap GCC with a sequence of assemblers, interpreters, and compilers
41244 of increasing complexity, which could be built from source starting from
41245 a simple and auditable assembler.
41247 Our first major achievement is the replacement of of GCC, the GNU C Library
41248 and Binutils by MesCC-Tools (a simple hex linker and macro assembler) and Mes
41249 (@pxref{Top, GNU Mes Reference Manual,, mes, GNU Mes}, a Scheme interpreter
41250 and C compiler in Scheme). Neither MesCC-Tools nor Mes can be fully
41251 bootstrapped yet and thus we inject them as binary seeds. We call this the
41252 Reduced Binary Seed bootstrap, as it has halved the size of our bootstrap
41253 binaries! Also, it has eliminated the C compiler binary; i686-linux and
41254 x86_64-linux Guix packages are now bootstrapped without any binary C compiler.
41256 Work is ongoing to make MesCC-Tools and Mes fully bootstrappable and we are
41257 also looking at any other bootstrap binaries. Your help is welcome!
41260 @chapter Porting to a New Platform
41262 As discussed above, the GNU distribution is self-contained, and
41263 self-containment is achieved by relying on pre-built ``bootstrap
41264 binaries'' (@pxref{Bootstrapping}). These binaries are specific to an
41265 operating system kernel, CPU architecture, and application binary
41266 interface (ABI). Thus, to port the distribution to a platform that is
41267 not yet supported, one must build those bootstrap binaries, and update
41268 the @code{(gnu packages bootstrap)} module to use them on that platform.
41270 Fortunately, Guix can @emph{cross compile} those bootstrap binaries.
41271 When everything goes well, and assuming the GNU tool chain supports the
41272 target platform, this can be as simple as running a command like this
41276 guix build --target=armv5tel-linux-gnueabi bootstrap-tarballs
41279 For this to work, it is first required to register a new platform as
41280 defined in the @code{(guix platform)} module. A platform is making the
41281 connection between a GNU triplet (@pxref{Specifying Target Triplets, GNU
41282 configuration triplets,, autoconf, Autoconf}), the equivalent
41283 @var{system} in Nix notation, the name of the
41284 @var{glibc-dynamic-linker}, and the corresponding Linux architecture
41285 name if applicable.
41287 Once the bootstrap tarball are built, the @code{(gnu packages
41288 bootstrap)} module needs to be updated to refer to these binaries on the
41289 target platform. That is, the hashes and URLs of the bootstrap tarballs
41290 for the new platform must be added alongside those of the currently
41291 supported platforms. The bootstrap Guile tarball is treated specially:
41292 it is expected to be available locally, and @file{gnu/local.mk} has
41293 rules to download it for the supported architectures; a rule for the new
41294 platform must be added as well.
41296 In practice, there may be some complications. First, it may be that the
41297 extended GNU triplet that specifies an ABI (like the @code{eabi} suffix
41298 above) is not recognized by all the GNU tools. Typically, glibc
41299 recognizes some of these, whereas GCC uses an extra @option{--with-abi}
41300 configure flag (see @code{gcc.scm} for examples of how to handle this).
41301 Second, some of the required packages could fail to build for that
41302 platform. Lastly, the generated binaries could be broken for some
41305 @c *********************************************************************
41306 @include contributing.texi
41308 @c *********************************************************************
41309 @node Acknowledgments
41310 @chapter Acknowledgments
41312 Guix is based on the @uref{https://nixos.org/nix/, Nix package manager},
41313 which was designed and
41314 implemented by Eelco Dolstra, with contributions from other people (see
41315 the @file{nix/AUTHORS} file in Guix). Nix pioneered functional package
41316 management, and promoted unprecedented features, such as transactional
41317 package upgrades and rollbacks, per-user profiles, and referentially
41318 transparent build processes. Without this work, Guix would not exist.
41320 The Nix-based software distributions, Nixpkgs and NixOS, have also been
41321 an inspiration for Guix.
41323 GNU@tie{}Guix itself is a collective work with contributions from a
41324 number of people. See the @file{AUTHORS} file in Guix for more
41325 information on these fine people. The @file{THANKS} file lists people
41326 who have helped by reporting bugs, taking care of the infrastructure,
41327 providing artwork and themes, making suggestions, and more---thank you!
41330 @c *********************************************************************
41331 @node GNU Free Documentation License
41332 @appendix GNU Free Documentation License
41333 @cindex license, GNU Free Documentation License
41334 @include fdl-1.3.texi
41336 @c *********************************************************************
41337 @node Concept Index
41338 @unnumbered Concept Index
41341 @node Programming Index
41342 @unnumbered Programming Index
41343 @syncodeindex tp fn
41344 @syncodeindex vr fn
41349 @c Local Variables:
41350 @c ispell-local-dictionary: "american";