diff --git a/doc/manual/command-ref/conf-file.xml b/doc/manual/command-ref/conf-file.xml deleted file mode 100644 index d0f1b09ca..000000000 --- a/doc/manual/command-ref/conf-file.xml +++ /dev/null @@ -1,1236 +0,0 @@ - - - - - nix.conf - 5 - Nix - - - - - nix.conf - Nix configuration file - - -Description - -By default Nix reads settings from the following places: - -The system-wide configuration file -sysconfdir/nix/nix.conf -(i.e. /etc/nix/nix.conf on most systems), or -$NIX_CONF_DIR/nix.conf if -NIX_CONF_DIR is set. Values loaded in this file are not forwarded to the Nix daemon. The -client assumes that the daemon has already loaded them. - - -User-specific configuration files: - - - If NIX_USER_CONF_FILES is set, then each path separated by - : will be loaded in reverse order. - - - - Otherwise it will look for nix/nix.conf files in - XDG_CONFIG_DIRS and XDG_CONFIG_HOME. - - The default location is $HOME/.config/nix.conf if - those environment variables are unset. - - -The configuration files consist of -name = -value pairs, one per line. Other -files can be included with a line like include -path, where -path is interpreted relative to the current -conf file and a missing file is an error unless -!include is used instead. -Comments start with a # character. Here is an -example configuration file: - - -keep-outputs = true # Nice for developers -keep-derivations = true # Idem - - -You can override settings on the command line using the - flag, e.g. --option keep-outputs -false. - -The following settings are currently available: - - - - - allowed-uris - - - - A list of URI prefixes to which access is allowed in - restricted evaluation mode. For example, when set to - https://github.com/NixOS, builtin functions - such as fetchGit are allowed to access - https://github.com/NixOS/patchelf.git. - - - - - - - allow-import-from-derivation - - By default, Nix allows you to import from a derivation, - allowing building at evaluation time. With this option set to false, Nix will throw an error - when evaluating an expression that uses this feature, allowing users to ensure their evaluation - will not require any builds to take place. - - - - - allow-new-privileges - - (Linux-specific.) By default, builders on Linux - cannot acquire new privileges by calling setuid/setgid programs or - programs that have file capabilities. For example, programs such - as sudo or ping will - fail. (Note that in sandbox builds, no such programs are available - unless you bind-mount them into the sandbox via the - option.) You can allow the - use of such programs by enabling this option. This is impure and - usually undesirable, but may be useful in certain scenarios - (e.g. to spin up containers or set up userspace network interfaces - in tests). - - - - - allowed-users - - - - A list of names of users (separated by whitespace) that - are allowed to connect to the Nix daemon. As with the - option, you can specify groups by - prefixing them with @. Also, you can allow - all users by specifying *. The default is - *. - - Note that trusted users are always allowed to connect. - - - - - - - auto-optimise-store - - If set to true, Nix - automatically detects files in the store that have identical - contents, and replaces them with hard links to a single copy. - This saves disk space. If set to false (the - default), you can still run nix-store - --optimise to get rid of duplicate - files. - - - - - builders - - A list of machines on which to perform builds. See for details. - - - - - builders-use-substitutes - - If set to true, Nix will instruct - remote build machines to use their own binary substitutes if available. In - practical terms, this means that remote hosts will fetch as many build - dependencies as possible from their own substitutes (e.g, from - cache.nixos.org), instead of waiting for this host to - upload them all. This can drastically reduce build times if the network - connection between this computer and the remote build host is slow. Defaults - to false. - - - - build-users-group - - This options specifies the Unix group containing - the Nix build user accounts. In multi-user Nix installations, - builds should not be performed by the Nix account since that would - allow users to arbitrarily modify the Nix store and database by - supplying specially crafted builders; and they cannot be performed - by the calling user since that would allow him/her to influence - the build result. - - Therefore, if this option is non-empty and specifies a valid - group, builds will be performed under the user accounts that are a - member of the group specified here (as listed in - /etc/group). Those user accounts should not - be used for any other purpose! - - Nix will never run two builds under the same user account at - the same time. This is to prevent an obvious security hole: a - malicious user writing a Nix expression that modifies the build - result of a legitimate Nix expression being built by another user. - Therefore it is good to have as many Nix build user accounts as - you can spare. (Remember: uids are cheap.) - - The build users should have permission to create files in - the Nix store, but not delete them. Therefore, - /nix/store should be owned by the Nix - account, its group should be the group specified here, and its - mode should be 1775. - - If the build users group is empty, builds will be performed - under the uid of the Nix process (that is, the uid of the caller - if NIX_REMOTE is empty, the uid under which the Nix - daemon runs if NIX_REMOTE is - daemon). Obviously, this should not be used in - multi-user settings with untrusted users. - - - - - - - compress-build-log - - If set to true (the default), - build logs written to /nix/var/log/nix/drvs - will be compressed on the fly using bzip2. Otherwise, they will - not be compressed. - - - - connect-timeout - - - - The timeout (in seconds) for establishing connections in - the binary cache substituter. It corresponds to - curl’s - option. - - - - - - - cores - - Sets the value of the - NIX_BUILD_CORES environment variable in the - invocation of builders. Builders can use this variable at their - discretion to control the maximum amount of parallelism. For - instance, in Nixpkgs, if the derivation attribute - enableParallelBuilding is set to - true, the builder passes the - flag to GNU Make. - It can be overridden using the command line switch and - defaults to 1. The value 0 - means that the builder should use all available CPU cores in the - system. - - See also . - - - diff-hook - - - Absolute path to an executable capable of diffing build results. - The hook executes if is - true, and the output of a build is known to not be the same. - This program is not executed to determine if two results are the - same. - - - - The diff hook is executed by the same user and group who ran the - build. However, the diff hook does not have write access to the - store path just built. - - - The diff hook program receives three parameters: - - - - - A path to the previous build's results - - - - - - A path to the current build's results - - - - - - The path to the build's derivation - - - - - - The path to the build's scratch directory. This directory - will exist only if the build was run with - . - - - - - - The stderr and stdout output from the diff hook will not be - displayed to the user. Instead, it will print to the nix-daemon's - log. - - - When using the Nix daemon, diff-hook must - be set in the nix.conf configuration file, and - cannot be passed at the command line. - - - - - - enforce-determinism - - See . - - - - extra-sandbox-paths - - A list of additional paths appended to - . Useful if you want to extend - its default value. - - - - - extra-platforms - - Platforms other than the native one which - this machine is capable of building for. This can be useful for - supporting additional architectures on compatible machines: - i686-linux can be built on x86_64-linux machines (and the default - for this setting reflects this); armv7 is backwards-compatible with - armv6 and armv5tel; some aarch64 machines can also natively run - 32-bit ARM code; and qemu-user may be used to support non-native - platforms (though this may be slow and buggy). Most values for this - are not enabled by default because build systems will often - misdetect the target platform and generate incompatible code, so you - may wish to cross-check the results of using this option against - proper natively-built versions of your - derivations. - - - - - extra-substituters - - Additional binary caches appended to those - specified in . When used by - unprivileged users, untrusted substituters (i.e. those not listed - in ) are silently - ignored. - - - - fallback - - If set to true, Nix will fall - back to building from source if a binary substitute fails. This - is equivalent to the flag. The - default is false. - - - - fsync-metadata - - If set to true, changes to the - Nix store metadata (in /nix/var/nix/db) are - synchronously flushed to disk. This improves robustness in case - of system crashes, but reduces performance. The default is - true. - - - - hashed-mirrors - - A list of web servers used by - builtins.fetchurl to obtain files by hash. - Given a hash type ht and a base-16 hash - h, Nix will try to download the file - from - hashed-mirror/ht/h. - This allows files to be downloaded even if they have disappeared - from their original URI. For example, given the hashed mirror - http://tarballs.example.com/, when building the - derivation - - -builtins.fetchurl { - url = "https://example.org/foo-1.2.3.tar.xz"; - sha256 = "2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae"; -} - - - Nix will attempt to download this file from - http://tarballs.example.com/sha256/2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae - first. If it is not available there, if will try the original URI. - - - - - http-connections - - The maximum number of parallel TCP connections - used to fetch files from binary caches and by other downloads. It - defaults to 25. 0 means no limit. - - - - - keep-build-log - - If set to true (the default), - Nix will write the build log of a derivation (i.e. the standard - output and error of its builder) to the directory - /nix/var/log/nix/drvs. The build log can be - retrieved using the command nix-store -l - path. - - - - - keep-derivations - - If true (default), the garbage - collector will keep the derivations from which non-garbage store - paths were built. If false, they will be - deleted unless explicitly registered as a root (or reachable from - other roots). - - Keeping derivation around is useful for querying and - traceability (e.g., it allows you to ask with what dependencies or - options a store path was built), so by default this option is on. - Turn it off to save a bit of disk space (or a lot if - keep-outputs is also turned on). - - - keep-env-derivations - - If false (default), derivations - are not stored in Nix user environments. That is, the derivations of - any build-time-only dependencies may be garbage-collected. - - If true, when you add a Nix derivation to - a user environment, the path of the derivation is stored in the - user environment. Thus, the derivation will not be - garbage-collected until the user environment generation is deleted - (nix-env --delete-generations). To prevent - build-time-only dependencies from being collected, you should also - turn on keep-outputs. - - The difference between this option and - keep-derivations is that this one is - “sticky”: it applies to any user environment created while this - option was enabled, while keep-derivations - only applies at the moment the garbage collector is - run. - - - - keep-outputs - - If true, the garbage collector - will keep the outputs of non-garbage derivations. If - false (default), outputs will be deleted unless - they are GC roots themselves (or reachable from other roots). - - In general, outputs must be registered as roots separately. - However, even if the output of a derivation is registered as a - root, the collector will still delete store paths that are used - only at build time (e.g., the C compiler, or source tarballs - downloaded from the network). To prevent it from doing so, set - this option to true. - - - max-build-log-size - - - - This option defines the maximum number of bytes that a - builder can write to its stdout/stderr. If the builder exceeds - this limit, it’s killed. A value of 0 (the - default) means that there is no limit. - - - - - - max-free - - When a garbage collection is triggered by the - min-free option, it stops as soon as - max-free bytes are available. The default is - infinity (i.e. delete all garbage). - - - - max-jobs - - This option defines the maximum number of jobs - that Nix will try to build in parallel. The default is - 1. The special value auto - causes Nix to use the number of CPUs in your system. 0 - is useful when using remote builders to prevent any local builds (except for - preferLocalBuild derivation attribute which executes locally - regardless). It can be - overridden using the () - command line switch. - - See also . - - - - max-silent-time - - - - This option defines the maximum number of seconds that a - builder can go without producing any data on standard output or - standard error. This is useful (for instance in an automated - build system) to catch builds that are stuck in an infinite - loop, or to catch remote builds that are hanging due to network - problems. It can be overridden using the command - line switch. - - The value 0 means that there is no - timeout. This is also the default. - - - - - - min-free - - - When free disk space in /nix/store - drops below min-free during a build, Nix - performs a garbage-collection until max-free - bytes are available or there is no more garbage. A value of - 0 (the default) disables this feature. - - - - - narinfo-cache-negative-ttl - - - - The TTL in seconds for negative lookups. If a store path is - queried from a substituter but was not found, there will be a - negative lookup cached in the local disk cache database for the - specified duration. - - - - - - narinfo-cache-positive-ttl - - - - The TTL in seconds for positive lookups. If a store path is - queried from a substituter, the result of the query will be cached - in the local disk cache database including some of the NAR - metadata. The default TTL is a month, setting a shorter TTL for - positive lookups can be useful for binary caches that have - frequent garbage collection, in which case having a more frequent - cache invalidation would prevent trying to pull the path again and - failing with a hash mismatch if the build isn't reproducible. - - - - - - - netrc-file - - If set to an absolute path to a netrc - file, Nix will use the HTTP authentication credentials in this file when - trying to download from a remote host through HTTP or HTTPS. Defaults to - $NIX_CONF_DIR/netrc. - - The netrc file consists of a list of - accounts in the following format: - - -machine my-machine -login my-username -password my-password - - - For the exact syntax, see the - curl documentation. - - This must be an absolute path, and ~ - is not resolved. For example, ~/.netrc won't - resolve to your home directory's .netrc. - - - - - - - plugin-files - - - A list of plugin files to be loaded by Nix. Each of these - files will be dlopened by Nix, allowing them to affect - execution through static initialization. In particular, these - plugins may construct static instances of RegisterPrimOp to - add new primops or constants to the expression language, - RegisterStoreImplementation to add new store implementations, - RegisterCommand to add new subcommands to the - nix command, and RegisterSetting to add new - nix config settings. See the constructors for those types for - more details. - - - Since these files are loaded into the same address space as - Nix itself, they must be DSOs compatible with the instance of - Nix running at the time (i.e. compiled against the same - headers, not linked to any incompatible libraries). They - should not be linked to any Nix libs directly, as those will - be available already at load time. - - - If an entry in the list is a directory, all files in the - directory are loaded as plugins (non-recursively). - - - - - - pre-build-hook - - - - - If set, the path to a program that can set extra - derivation-specific settings for this system. This is used for settings - that can't be captured by the derivation model itself and are too variable - between different versions of the same system to be hard-coded into nix. - - - The hook is passed the derivation path and, if sandboxes are enabled, - the sandbox directory. It can then modify the sandbox and send a series of - commands to modify various settings to stdout. The currently recognized - commands are: - - - - extra-sandbox-paths - - - - Pass a list of files and directories to be included in the - sandbox for this build. One entry per line, terminated by an empty - line. Entries have the same format as - sandbox-paths. - - - - - - - - - - - post-build-hook - - Optional. The path to a program to execute after each build. - - This option is only settable in the global - nix.conf, or on the command line by trusted - users. - - When using the nix-daemon, the daemon executes the hook as - root. If the nix-daemon is not involved, the - hook runs as the user executing the nix-build. - - - The hook executes after an evaluation-time build. - The hook does not execute on substituted paths. - The hook's output always goes to the user's terminal. - If the hook fails, the build succeeds but no further builds execute. - The hook executes synchronously, and blocks other builds from progressing while it runs. - - - The program executes with no arguments. The program's environment - contains the following environment variables: - - - - DRV_PATH - - The derivation for the built paths. - Example: - /nix/store/5nihn1a7pa8b25l9zafqaqibznlvvp3f-bash-4.4-p23.drv - - - - - - OUT_PATHS - - Output paths of the built derivation, separated by a space character. - Example: - /nix/store/zf5lbh336mnzf1nlswdn11g4n2m8zh3g-bash-4.4-p23-dev - /nix/store/rjxwxwv1fpn9wa2x5ssk5phzwlcv4mna-bash-4.4-p23-doc - /nix/store/6bqvbzjkcp9695dq0dpl5y43nvy37pq1-bash-4.4-p23-info - /nix/store/r7fng3kk3vlpdlh2idnrbn37vh4imlj2-bash-4.4-p23-man - /nix/store/xfghy8ixrhz3kyy6p724iv3cxji088dx-bash-4.4-p23. - - - - - - See for an example - implementation. - - - - - repeat - - How many times to repeat builds to check whether - they are deterministic. The default value is 0. If the value is - non-zero, every build is repeated the specified number of - times. If the contents of any of the runs differs from the - previous ones and is - true, the build is rejected and the resulting store paths are not - registered as “valid” in Nix’s database. - - - require-sigs - - If set to true (the default), - any non-content-addressed path added or copied to the Nix store - (e.g. when substituting from a binary cache) must have a valid - signature, that is, be signed using one of the keys listed in - or - . Set to false - to disable signature checking. - - - - - restrict-eval - - - - If set to true, the Nix evaluator will - not allow access to any files outside of the Nix search path (as - set via the NIX_PATH environment variable or the - option), or to URIs outside of - . The default is - false. - - - - - - run-diff-hook - - - If true, enable the execution of . - - - - When using the Nix daemon, run-diff-hook must - be set in the nix.conf configuration file, - and cannot be passed at the command line. - - - - - sandbox - - If set to true, builds will be - performed in a sandboxed environment, i.e., - they’re isolated from the normal file system hierarchy and will - only see their dependencies in the Nix store, the temporary build - directory, private versions of /proc, - /dev, /dev/shm and - /dev/pts (on Linux), and the paths configured with the - sandbox-paths - option. This is useful to prevent undeclared dependencies - on files in directories such as /usr/bin. In - addition, on Linux, builds run in private PID, mount, network, IPC - and UTS namespaces to isolate them from other processes in the - system (except that fixed-output derivations do not run in private - network namespace to ensure they can access the network). - - Currently, sandboxing only work on Linux and macOS. The use - of a sandbox requires that Nix is run as root (so you should use - the “build users” - feature to perform the actual builds under different users - than root). - - If this option is set to relaxed, then - fixed-output derivations and derivations that have the - __noChroot attribute set to - true do not run in sandboxes. - - The default is true on Linux and - false on all other platforms. - - - - - - sandbox-dev-shm-size - - This option determines the maximum size of the - tmpfs filesystem mounted on - /dev/shm in Linux sandboxes. For the format, - see the description of the option of - tmpfs in - mount8. The - default is 50%. - - - - - - sandbox-paths - - A list of paths bind-mounted into Nix sandbox - environments. You can use the syntax - target=source - to mount a path in a different location in the sandbox; for - instance, /bin=/nix-bin will mount the path - /nix-bin as /bin inside the - sandbox. If source is followed by - ?, then it is not an error if - source does not exist; for example, - /dev/nvidiactl? specifies that - /dev/nvidiactl will only be mounted in the - sandbox if it exists in the host filesystem. - - Depending on how Nix was built, the default value for this option - may be empty or provide /bin/sh as a - bind-mount of bash. - - - - - secret-key-files - - A whitespace-separated list of files containing - secret (private) keys. These are used to sign locally-built - paths. They can be generated using nix-store - --generate-binary-cache-key. The corresponding public - key can be distributed to other users, who can add it to - in their - nix.conf. - - - - - show-trace - - Causes Nix to print out a stack trace in case of Nix - expression evaluation errors. - - - - - substitute - - If set to true (default), Nix - will use binary substitutes if available. This option can be - disabled to force building from source. - - - - stalled-download-timeout - - The timeout (in seconds) for receiving data from servers - during download. Nix cancels idle downloads after this timeout's - duration. - - - - substituters - - A list of URLs of substituters, separated by - whitespace. The default is - https://cache.nixos.org. - - - - system - - This option specifies the canonical Nix system - name of the current installation, such as - i686-linux or - x86_64-darwin. Nix can only build derivations - whose system attribute equals the value - specified here. In general, it never makes sense to modify this - value from its default, since you can use it to ‘lie’ about the - platform you are building on (e.g., perform a Mac OS build on a - Linux machine; the result would obviously be wrong). It only - makes sense if the Nix binaries can run on multiple platforms, - e.g., ‘universal binaries’ that run on x86_64-linux and - i686-linux. - - It defaults to the canonical Nix system name detected by - configure at build time. - - - - - system-features - - A set of system “features” supported by this - machine, e.g. kvm. Derivations can express a - dependency on such features through the derivation attribute - requiredSystemFeatures. For example, the - attribute - - -requiredSystemFeatures = [ "kvm" ]; - - - ensures that the derivation can only be built on a machine with - the kvm feature. - - This setting by default includes kvm if - /dev/kvm is accessible, and the - pseudo-features nixos-test, - benchmark and big-parallel - that are used in Nixpkgs to route builds to specific - machines. - - - - - - tarball-ttl - - - Default: 3600 seconds. - - The number of seconds a downloaded tarball is considered - fresh. If the cached tarball is stale, Nix will check whether - it is still up to date using the ETag header. Nix will download - a new version if the ETag header is unsupported, or the - cached ETag doesn't match. - - - Setting the TTL to 0 forces Nix to always - check if the tarball is up to date. - - Nix caches tarballs in - $XDG_CACHE_HOME/nix/tarballs. - - Files fetched via NIX_PATH, - fetchGit, fetchMercurial, - fetchTarball, and fetchurl - respect this TTL. - - - - - timeout - - - - This option defines the maximum number of seconds that a - builder can run. This is useful (for instance in an automated - build system) to catch builds that are stuck in an infinite loop - but keep writing to their standard output or standard error. It - can be overridden using the command line - switch. - - The value 0 means that there is no - timeout. This is also the default. - - - - - - trace-function-calls - - - - Default: false. - - If set to true, the Nix evaluator will - trace every function call. Nix will print a log message at the - "vomit" level for every function entrance and function exit. - - -function-trace entered undefined position at 1565795816999559622 -function-trace exited undefined position at 1565795816999581277 -function-trace entered /nix/store/.../example.nix:226:41 at 1565795253249935150 -function-trace exited /nix/store/.../example.nix:226:41 at 1565795253249941684 - - - The undefined position means the function - call is a builtin. - - Use the contrib/stack-collapse.py script - distributed with the Nix source code to convert the trace logs - in to a format suitable for flamegraph.pl. - - - - - - trusted-public-keys - - A whitespace-separated list of public keys. When - paths are copied from another Nix store (such as a binary cache), - they must be signed with one of these keys. For example: - cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= - hydra.nixos.org-1:CNHJZBh9K4tP3EKF6FkkgeVYsS3ohTl+oS0Qa8bezVs=. - - - - trusted-substituters - - A list of URLs of substituters, separated by - whitespace. These are not used by default, but can be enabled by - users of the Nix daemon by specifying --option - substituters urls on the - command line. Unprivileged users are only allowed to pass a - subset of the URLs listed in substituters and - trusted-substituters. - - - - trusted-users - - - - A list of names of users (separated by whitespace) that - have additional rights when connecting to the Nix daemon, such - as the ability to specify additional binary caches, or to import - unsigned NARs. You can also specify groups by prefixing them - with @; for instance, - @wheel means all users in the - wheel group. The default is - root. - - Adding a user to - is essentially equivalent to giving that user root access to the - system. For example, the user can set - and thereby obtain read access to - directories that are otherwise inacessible to - them. - - - - - - - - - - Deprecated Settings - - - - - - - binary-caches - - Deprecated: - binary-caches is now an alias to - . - - - - binary-cache-public-keys - - Deprecated: - binary-cache-public-keys is now an alias to - . - - - - build-compress-log - - Deprecated: - build-compress-log is now an alias to - . - - - - build-cores - - Deprecated: - build-cores is now an alias to - . - - - - build-extra-chroot-dirs - - Deprecated: - build-extra-chroot-dirs is now an alias to - . - - - - build-extra-sandbox-paths - - Deprecated: - build-extra-sandbox-paths is now an alias to - . - - - - build-fallback - - Deprecated: - build-fallback is now an alias to - . - - - - build-max-jobs - - Deprecated: - build-max-jobs is now an alias to - . - - - - build-max-log-size - - Deprecated: - build-max-log-size is now an alias to - . - - - - build-max-silent-time - - Deprecated: - build-max-silent-time is now an alias to - . - - - - build-repeat - - Deprecated: - build-repeat is now an alias to - . - - - - build-timeout - - Deprecated: - build-timeout is now an alias to - . - - - - build-use-chroot - - Deprecated: - build-use-chroot is now an alias to - . - - - - build-use-sandbox - - Deprecated: - build-use-sandbox is now an alias to - . - - - - build-use-substitutes - - Deprecated: - build-use-substitutes is now an alias to - . - - - - gc-keep-derivations - - Deprecated: - gc-keep-derivations is now an alias to - . - - - - gc-keep-outputs - - Deprecated: - gc-keep-outputs is now an alias to - . - - - - env-keep-derivations - - Deprecated: - env-keep-derivations is now an alias to - . - - - - extra-binary-caches - - Deprecated: - extra-binary-caches is now an alias to - . - - - - trusted-binary-caches - - Deprecated: - trusted-binary-caches is now an alias to - . - - - - - - - -