Warning
This program is experimental and its interface is subject to change.

Name

nix show-derivation - show the contents of a store derivation

Synopsis

nix show-derivation [option...] installables...

Examples

  • Show the store derivation that results from evaluating the Hello package:

    # nix show-derivation nixpkgs#hello
    {
      "/nix/store/s6rn4jz1sin56rf4qj5b5v8jxjm32hlk-hello-2.10.drv": {
        …
      }
    }
    
  • Show the full derivation graph (if available) that produced your NixOS system:

    # nix show-derivation -r /run/current-system
    
  • Print all files fetched using fetchurl by Firefox's dependency graph:

    # nix show-derivation -r nixpkgs#firefox \
      | jq -r '.[] | select(.outputs.out.hash and .env.urls) | .env.urls' \
      | uniq | sort
    

    Note that .outputs.out.hash selects fixed-output derivations (derivations that produce output with a specified content hash), while .env.urls selects derivations with a urls attribute.

Description

This command prints on standard output a JSON representation of the store derivations to which installables evaluate. Store derivations are used internally by Nix. They are store paths with extension .drv that represent the build-time dependency graph to which a Nix expression evaluates.

By default, this command only shows top-level derivations, but with --recursive, it also shows their dependencies.

The JSON output is a JSON object whose keys are the store paths of the derivations, and whose values are a JSON object with the following fields:

  • outputs: Information about the output paths of the derivation. This is a JSON object with one member per output, where the key is the output name and the value is a JSON object with these fields:

    • path: The output path.
    • hashAlgo: For fixed-output derivations, the hashing algorithm (e.g. sha256), optionally prefixed by r: if hash denotes a NAR hash rather than a flat file hash.
    • hash: For fixed-output derivations, the expected content hash in base-16.

    Example:

    "outputs": {
      "out": {
        "path": "/nix/store/2543j7c6jn75blc3drf4g5vhb1rhdq29-source",
        "hashAlgo": "r:sha256",
        "hash": "6fc80dcc62179dbc12fc0b5881275898f93444833d21b89dfe5f7fbcbb1d0d62"
      }
    }
    
  • inputSrcs: A list of store paths on which this derivation depends.

  • inputDrvs: A JSON object specifying the derivations on which this derivation depends, and what outputs of those derivations. For example,

    "inputDrvs": {
      "/nix/store/6lkh5yi7nlb7l6dr8fljlli5zfd9hq58-curl-7.73.0.drv": ["dev"],
      "/nix/store/fn3kgnfzl5dzym26j8g907gq3kbm8bfh-unzip-6.0.drv": ["out"]
    }
    

    specifies that this derivation depends on the dev output of curl, and the out output of unzip.

  • system: The system type on which this derivation is to be built (e.g. x86_64-linux).

  • builder: The absolute path of the program to be executed to run the build. Typically this is the bash shell (e.g. /nix/store/r3j288vpmczbl500w6zz89gyfa4nr0b1-bash-4.4-p23/bin/bash).

  • args: The command-line arguments passed to the builder.

  • env: The environment passed to the builder.

Options

  • --recursive / -r

    Include the dependencies of the specified derivations.

Common evaluation options:

  • --arg name expr

    Pass the value expr as the argument name to Nix functions.

  • --argstr name string

    Pass the string string as the argument name to Nix functions.

  • --debugger

    Start an interactive environment if evaluation fails.

  • --eval-store store-url

    The Nix store to use for evaluations.

  • --impure

    Allow access to mutable paths and repositories.

  • --include / -I path

    Add path to the Nix search path. The Nix search path is initialized from the colon-separated NIX_PATH environment variable, and is used to look up the location of Nix expressions using paths enclosed in angle brackets (i.e., <nixpkgs>).

    For instance, passing

    -I /home/eelco/Dev
    -I /etc/nixos
    

    will cause Nix to look for paths relative to /home/eelco/Dev and /etc/nixos, in that order. This is equivalent to setting the NIX_PATH environment variable to

    /home/eelco/Dev:/etc/nixos
    

    It is also possible to match paths against a prefix. For example, passing

    -I nixpkgs=/home/eelco/Dev/nixpkgs-branch
    -I /etc/nixos
    

    will cause Nix to search for <nixpkgs/path> in /home/eelco/Dev/nixpkgs-branch/path and /etc/nixos/nixpkgs/path.

    If a path in the Nix search path starts with http:// or https://, it is interpreted as the URL of a tarball that will be downloaded and unpacked to a temporary location. The tarball must consist of a single top-level directory. For example, passing

    -I nixpkgs=https://github.com/NixOS/nixpkgs/archive/master.tar.gz
    

    tells Nix to download and use the current contents of the master branch in the nixpkgs repository.

    The URLs of the tarballs from the official nixos.org channels (see the manual page for nix-channel) can be abbreviated as channel:<channel-name>. For instance, the following two flags are equivalent:

    -I nixpkgs=channel:nixos-21.05
    -I nixpkgs=https://nixos.org/channels/nixos-21.05/nixexprs.tar.xz
    

    You can also fetch source trees using flake URLs and add them to the search path. For instance,

    -I nixpkgs=flake:nixpkgs
    

    specifies that the prefix nixpkgs shall refer to the source tree downloaded from the nixpkgs entry in the flake registry. Similarly,

    -I nixpkgs=flake:github:NixOS/nixpkgs/nixos-22.05
    

    makes <nixpkgs> refer to a particular branch of the NixOS/nixpkgs repository on GitHub.

  • --override-flake original-ref resolved-ref

    Override the flake registries, redirecting original-ref to resolved-ref.

Common flake-related options:

  • --commit-lock-file

    Commit changes to the flake's lock file.

  • --inputs-from flake-url

    Use the inputs of the specified flake as registry entries.

  • --no-registries

    Don't allow lookups in the flake registries. This option is deprecated; use --no-use-registries.

  • --no-update-lock-file

    Do not allow any updates to the flake's lock file.

  • --no-write-lock-file

    Do not write the flake's newly generated lock file.

  • --override-input input-path flake-url

    Override a specific flake input (e.g. dwarffs/nixpkgs). This implies --no-write-lock-file.

  • --recreate-lock-file

    Recreate the flake's lock file from scratch.

  • --update-input input-path

    Update a specific flake input (ignoring its previous entry in the lock file).

Logging-related options:

  • --debug

    Set the logging verbosity level to 'debug'.

  • --log-format format

    Set the format of log output; one of raw, internal-json, bar or bar-with-logs.

  • --print-build-logs / -L

    Print full build logs on standard error.

  • --quiet

    Decrease the logging verbosity level.

  • --verbose / -v

    Increase the logging verbosity level.

Miscellaneous global options:

  • --help

    Show usage information.

  • --offline

    Disable substituters and consider all previously downloaded files up-to-date.

  • --option name value

    Set the Nix configuration setting name to value (overriding nix.conf).

  • --refresh

    Consider all previously downloaded files out-of-date.

  • --version

    Show version information.

Options that change the interpretation of installables:

  • --derivation

    Operate on the store derivation rather than its outputs.

  • --expr expr

    Interpret installables as attribute paths relative to the Nix expression expr.

  • --file / -f file

    Interpret installables as attribute paths relative to the Nix expression stored in file. If file is the character -, then a Nix expression will be read from standard input. Implies --impure.

Options to override configuration settings:

  • --accept-flake-config

    Enable the accept-flake-config setting.

  • --access-tokens value

    Set the access-tokens setting.

  • --allow-dirty

    Enable the allow-dirty setting.

  • --allow-import-from-derivation

    Enable the allow-import-from-derivation setting.

  • --allow-new-privileges

    Enable the allow-new-privileges setting.

  • --allow-symlinked-store

    Enable the allow-symlinked-store setting.

  • --allow-unsafe-native-code-during-evaluation

    Enable the allow-unsafe-native-code-during-evaluation setting.

  • --allowed-impure-host-deps value

    Set the allowed-impure-host-deps setting.

  • --allowed-uris value

    Set the allowed-uris setting.

  • --allowed-users value

    Set the allowed-users setting.

  • --auto-allocate-uids

    Enable the auto-allocate-uids setting.

  • --auto-optimise-store

    Enable the auto-optimise-store setting.

  • --bash-prompt value

    Set the bash-prompt setting.

  • --bash-prompt-prefix value

    Set the bash-prompt-prefix setting.

  • --bash-prompt-suffix value

    Set the bash-prompt-suffix setting.

  • --build-hook value

    Set the build-hook setting.

  • --build-poll-interval value

    Set the build-poll-interval setting.

  • --build-users-group value

    Set the build-users-group setting.

  • --builders value

    Set the builders setting.

  • --builders-use-substitutes

    Enable the builders-use-substitutes setting.

  • --commit-lockfile-summary value

    Set the commit-lockfile-summary setting.

  • --compress-build-log

    Enable the compress-build-log setting.

  • --connect-timeout value

    Set the connect-timeout setting.

  • --cores value

    Set the cores setting.

  • --diff-hook value

    Set the diff-hook setting.

  • --download-attempts value

    Set the download-attempts setting.

  • --download-speed value

    Set the download-speed setting.

  • --eval-cache

    Enable the eval-cache setting.

  • --experimental-features value

    Set the experimental-features setting.

  • --extra-access-tokens value

    Append to the access-tokens setting.

  • --extra-allowed-impure-host-deps value

    Append to the allowed-impure-host-deps setting.

  • --extra-allowed-uris value

    Append to the allowed-uris setting.

  • --extra-allowed-users value

    Append to the allowed-users setting.

  • --extra-experimental-features value

    Append to the experimental-features setting.

  • --extra-extra-platforms value

    Append to the extra-platforms setting.

  • --extra-hashed-mirrors value

    Append to the hashed-mirrors setting.

  • --extra-ignored-acls value

    Append to the ignored-acls setting.

  • --extra-nix-path value

    Append to the nix-path setting.

  • --extra-platforms value

    Set the extra-platforms setting.

  • --extra-plugin-files value

    Append to the plugin-files setting.

  • --extra-sandbox-paths value

    Append to the sandbox-paths setting.

  • --extra-secret-key-files value

    Append to the secret-key-files setting.

  • --extra-substituters value

    Append to the substituters setting.

  • --extra-system-features value

    Append to the system-features setting.

  • --extra-trusted-public-keys value

    Append to the trusted-public-keys setting.

  • --extra-trusted-substituters value

    Append to the trusted-substituters setting.

  • --extra-trusted-users value

    Append to the trusted-users setting.

  • --fallback

    Enable the fallback setting.

  • --filter-syscalls

    Enable the filter-syscalls setting.

  • --flake-registry value

    Set the flake-registry setting.

  • --fsync-metadata

    Enable the fsync-metadata setting.

  • --gc-reserved-space value

    Set the gc-reserved-space setting.

  • --hashed-mirrors value

    Set the hashed-mirrors setting.

  • --http-connections value

    Set the http-connections setting.

  • --http2

    Enable the http2 setting.

  • --id-count value

    Set the id-count setting.

  • --ignore-try

    Enable the ignore-try setting.

  • --ignored-acls value

    Set the ignored-acls setting.

  • --impersonate-linux-26

    Enable the impersonate-linux-26 setting.

  • --keep-build-log

    Enable the keep-build-log setting.

  • --keep-derivations

    Enable the keep-derivations setting.

  • --keep-env-derivations

    Enable the keep-env-derivations setting.

  • --keep-failed

    Enable the keep-failed setting.

  • --keep-going

    Enable the keep-going setting.

  • --keep-outputs

    Enable the keep-outputs setting.

  • --log-lines value

    Set the log-lines setting.

  • --max-build-log-size value

    Set the max-build-log-size setting.

  • --max-free value

    Set the max-free setting.

  • --max-jobs value

    Set the max-jobs setting.

  • --max-silent-time value

    Set the max-silent-time setting.

  • --min-free value

    Set the min-free setting.

  • --min-free-check-interval value

    Set the min-free-check-interval setting.

  • --nar-buffer-size value

    Set the nar-buffer-size setting.

  • --narinfo-cache-negative-ttl value

    Set the narinfo-cache-negative-ttl setting.

  • --narinfo-cache-positive-ttl value

    Set the narinfo-cache-positive-ttl setting.

  • --netrc-file value

    Set the netrc-file setting.

  • --nix-path value

    Set the nix-path setting.

  • --no-accept-flake-config

    Disable the accept-flake-config setting.

  • --no-allow-dirty

    Disable the allow-dirty setting.

  • --no-allow-import-from-derivation

    Disable the allow-import-from-derivation setting.

  • --no-allow-new-privileges

    Disable the allow-new-privileges setting.

  • --no-allow-symlinked-store

    Disable the allow-symlinked-store setting.

  • --no-allow-unsafe-native-code-during-evaluation

    Disable the allow-unsafe-native-code-during-evaluation setting.

  • --no-auto-allocate-uids

    Disable the auto-allocate-uids setting.

  • --no-auto-optimise-store

    Disable the auto-optimise-store setting.

  • --no-builders-use-substitutes

    Disable the builders-use-substitutes setting.

  • --no-compress-build-log

    Disable the compress-build-log setting.

  • --no-eval-cache

    Disable the eval-cache setting.

  • --no-fallback

    Disable the fallback setting.

  • --no-filter-syscalls

    Disable the filter-syscalls setting.

  • --no-fsync-metadata

    Disable the fsync-metadata setting.

  • --no-http2

    Disable the http2 setting.

  • --no-ignore-try

    Disable the ignore-try setting.

  • --no-impersonate-linux-26

    Disable the impersonate-linux-26 setting.

  • --no-keep-build-log

    Disable the keep-build-log setting.

  • --no-keep-derivations

    Disable the keep-derivations setting.

  • --no-keep-env-derivations

    Disable the keep-env-derivations setting.

  • --no-keep-failed

    Disable the keep-failed setting.

  • --no-keep-going

    Disable the keep-going setting.

  • --no-keep-outputs

    Disable the keep-outputs setting.

  • --no-preallocate-contents

    Disable the preallocate-contents setting.

  • --no-print-missing

    Disable the print-missing setting.

  • --no-pure-eval

    Disable the pure-eval setting.

  • --no-require-sigs

    Disable the require-sigs setting.

  • --no-restrict-eval

    Disable the restrict-eval setting.

  • --no-run-diff-hook

    Disable the run-diff-hook setting.

  • --no-sandbox

    Disable sandboxing.

  • --no-sandbox-fallback

    Disable the sandbox-fallback setting.

  • --no-show-trace

    Disable the show-trace setting.

  • --no-substitute

    Disable the substitute setting.

  • --no-sync-before-registering

    Disable the sync-before-registering setting.

  • --no-trace-function-calls

    Disable the trace-function-calls setting.

  • --no-trace-verbose

    Disable the trace-verbose setting.

  • --no-use-case-hack

    Disable the use-case-hack setting.

  • --no-use-cgroups

    Disable the use-cgroups setting.

  • --no-use-registries

    Disable the use-registries setting.

  • --no-use-sqlite-wal

    Disable the use-sqlite-wal setting.

  • --no-warn-dirty

    Disable the warn-dirty setting.

  • --plugin-files value

    Set the plugin-files setting.

  • --post-build-hook value

    Set the post-build-hook setting.

  • --pre-build-hook value

    Set the pre-build-hook setting.

  • --preallocate-contents

    Enable the preallocate-contents setting.

  • --print-missing

    Enable the print-missing setting.

  • --pure-eval

    Enable the pure-eval setting.

  • --relaxed-sandbox

    Enable sandboxing, but allow builds to disable it.

  • --require-sigs

    Enable the require-sigs setting.

  • --restrict-eval

    Enable the restrict-eval setting.

  • --run-diff-hook

    Enable the run-diff-hook setting.

  • --sandbox

    Enable sandboxing.

  • --sandbox-build-dir value

    Set the sandbox-build-dir setting.

  • --sandbox-dev-shm-size value

    Set the sandbox-dev-shm-size setting.

  • --sandbox-fallback

    Enable the sandbox-fallback setting.

  • --sandbox-paths value

    Set the sandbox-paths setting.

  • --secret-key-files value

    Set the secret-key-files setting.

  • --show-trace

    Enable the show-trace setting.

  • --stalled-download-timeout value

    Set the stalled-download-timeout setting.

  • --start-id value

    Set the start-id setting.

  • --store value

    Set the store setting.

  • --substitute

    Enable the substitute setting.

  • --substituters value

    Set the substituters setting.

  • --sync-before-registering

    Enable the sync-before-registering setting.

  • --system value

    Set the system setting.

  • --system-features value

    Set the system-features setting.

  • --tarball-ttl value

    Set the tarball-ttl setting.

  • --timeout value

    Set the timeout setting.

  • --trace-function-calls

    Enable the trace-function-calls setting.

  • --trace-verbose

    Enable the trace-verbose setting.

  • --trusted-public-keys value

    Set the trusted-public-keys setting.

  • --trusted-substituters value

    Set the trusted-substituters setting.

  • --trusted-users value

    Set the trusted-users setting.

  • --use-case-hack

    Enable the use-case-hack setting.

  • --use-cgroups

    Enable the use-cgroups setting.

  • --use-registries

    Enable the use-registries setting.

  • --use-sqlite-wal

    Enable the use-sqlite-wal setting.

  • --user-agent-suffix value

    Set the user-agent-suffix setting.

  • --warn-dirty

    Enable the warn-dirty setting.