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

Name

nix derivation show - show the contents of a store derivation

Synopsis

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

Examples

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

# nix derivation show nixpkgs#hello
{
  "/nix/store/s6rn4jz1sin56rf4qj5b5v8jxjm32hlk-hello-2.10.drv": {
    …
  }
}

Show the full derivation graph (if available) that produced your NixOS system:
```
# nix derivation show -r /run/current-system
```
Print all files fetched using fetchurl by Firefox's dependency graph:
```
# nix derivation show -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.

nix derivation show outputs a JSON map of store paths to derivations in the following format:

Derivation JSON Format

Warning

This JSON format is currently experimental and subject to change.

The JSON serialization of a derivations is a JSON object with the following fields:

name: The name of the derivation. This is used when calculating the store paths of the derivation's outputs.
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, if it is known in advanced. Otherwise, null.
- method: For an output which will be [content addresed], a string representing the method of content addressing that is chosen. Valid method strings are:
  - flat
  - nar
  - text
  - git
  Otherwise, null.
- hashAlgo: For an output which will be [content addresed], the name of the hash algorithm used. Valid algorithm strings are:
  - md5
  - sha1
  - sha256
  - sha512
- hash: For fixed-output derivations, the expected content hash in base-16.
Example
```
"outputs": {
  "out": {
    "path": "/nix/store/2543j7c6jn75blc3drf4g5vhb1rhdq29-source",
    "method": "nar",
    "hashAlgo": "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.
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.
--stdin

Read installables from the standard input. No default installable applied.

Common evaluation options

--arg name expr

Pass the value expr as the argument name to Nix functions.
--arg-from-file name path

Pass the contents of file path as the argument name to Nix functions.
--arg-from-stdin name

Pass the contents of stdin 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 URL of the Nix store to use for evaluation, i.e. to store derivations (.drv files) and inputs referenced by them.
--impure

Allow access to mutable paths and repositories.
--include / -I path

Add path to search path entries used to resolve lookup paths

This option may be given multiple times.

Paths added through -I take precedence over the nix-path configuration setting and the NIX_PATH environment variable.
--override-flake original-ref resolved-ref

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

--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.

DEPRECATED

Use --no-use-registries instead.
--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.
--output-lock-file flake-lock-path

Write the given lock file instead of flake.lock within the top-level flake.
--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.

DEPRECATED

Use nix flake update instead.
--reference-lock-file flake-lock-path

Read the given lock file instead of flake.lock within the top-level flake.
--update-input input-path

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

DEPRECATED

Use nix flake update instead.

--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.
--repair

During evaluation, rewrite missing or corrupted files in the Nix store. During building, rebuild missing or corrupted store paths.
--version

Show version information.

Options that change the interpretation of installables

--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.

Note

See man nix.conf for overriding configuration settings with command line flags.

Nix Reference Manual