Man page - nix3-why-depends(1)

Packages contains this manual

Manual

nix3-why-depends

Name
Synopsis
Examples
Description
Options
Common evaluation options
Common flake-related options
Logging-related options
Miscellaneous global options
Options that change the interpretation of installables

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

Name

nix why-depends - show why a package has another package in its closure

Synopsis

nix why-depends [ option …] package dependency

Examples

•

Show one path through the dependency graph leading from Hello to Glibc:

# nix why-depends nixpkgs#hello nixpkgs#glibc
/nix/store/v5sv61sszx301i0x6xysaqzla09nksnd-hello-2.10
└───bin/hello: …...................../nix/store/9l06v7fc38c1x3r2iydl15ksgz0ysb82-glibc-2.32/lib/ld-linux-x86-64.…
→ /nix/store/9l06v7fc38c1x3r2iydl15ksgz0ysb82-glibc-2.32

•

Show all files and paths in the dependency graph leading from Thunderbird to libX11:

# nix why-depends --all nixpkgs#thunderbird nixpkgs#xorg.libX11
/nix/store/qfc8729nzpdln1h0hvi1ziclsl3m84sr-thunderbird-78.5.1
├───lib/thunderbird/libxul.so: …6wrw-libxcb-1.14/lib:/nix/store/adzfjjh8w25vdr0xdx9x16ah4f5rqrw5-libX11-1.7.0/lib:/nix/store/ssf…
│ → /nix/store/adzfjjh8w25vdr0xdx9x16ah4f5rqrw5-libX11-1.7.0
├───lib/thunderbird/libxul.so: …pxyc-libXt-1.2.0/lib:/nix/store/1qj29ipxl2fyi2b13l39hdircq17gnk0-libXdamage-1.1.5/lib:/nix/store…
│ → /nix/store/1qj29ipxl2fyi2b13l39hdircq17gnk0-libXdamage-1.1.5
│ ├───lib/libXdamage.so.1.1.0: …-libXfixes-5.0.3/lib:/nix/store/adzfjjh8w25vdr0xdx9x16ah4f5rqrw5-libX11-1.7.0/lib:/nix/store/9l0…
│ │ → /nix/store/adzfjjh8w25vdr0xdx9x16ah4f5rqrw5-libX11-1.7.0
…

•

Show why Glibc depends on itself:

# nix why-depends nixpkgs#glibc nixpkgs#glibc
/nix/store/9df65igwjmf2wbw0gbrrgair6piqjgmi-glibc-2.31
└───lib/ld-2.31.so: …che Do not use /nix/store/9df65igwjmf2wbw0gbrrgair6piqjgmi-glibc-2.31/etc/ld.so.cache. --…
→ /nix/store/9df65igwjmf2wbw0gbrrgair6piqjgmi-glibc-2.31

•

Show why Geeqie has a build-time dependency on systemd:

# nix why-depends --derivation nixpkgs#geeqie nixpkgs#systemd
/nix/store/drrpq2fqlrbj98bmazrnww7hm1in3wgj-geeqie-1.4.drv
└───/: …atch.drv",["out"]),("/nix/store/qzh8dyq3lfbk3i1acbp7x9wh3il2imiv-gtk+3-3.24.21.drv",["dev"]),("/…
→ /nix/store/qzh8dyq3lfbk3i1acbp7x9wh3il2imiv-gtk+3-3.24.21.drv
└───/: …16.0.drv",["dev"]),("/nix/store/8kp79fyslf3z4m3dpvlh6w46iaadz5c2-cups-2.3.3.drv",["dev"]),("/nix…
→ /nix/store/8kp79fyslf3z4m3dpvlh6w46iaadz5c2-cups-2.3.3.drv
└───/: ….3.1.drv",["out"]),("/nix/store/yd3ihapyi5wbz1kjacq9dbkaq5v5hqjg-systemd-246.4.drv",["dev"]),("/…
→ /nix/store/yd3ihapyi5wbz1kjacq9dbkaq5v5hqjg-systemd-246.4.drv

Description

Nix automatically determines potential runtime dependencies between store paths by scanning for the hash parts of store paths. For instance, if there exists a store path /nix/store/9df65igwjmf2wbw0gbrrgair6piqjgmi-glibc-2.31, and a file inside another store path contains the string 9df65igw…, then the latter store path refers to the former, and thus might need it at runtime. Nix always maintains the existence of the transitive closure of a store path under the references relationship; it is therefore not possible to install a store path without having all of its references present.

Sometimes Nix packages end up with unexpected runtime dependencies; for instance, a reference to a compiler might accidentally end up in a binary, causing the former to be in the latter’s closure. This kind of closure size bloat is undesirable.

nix why-depends allows you to diagnose the cause of such issues. It shows why the store path package depends on the store path dependency , by showing a shortest sequence in the references graph from the former to the latter. Also, for each node along this path, it shows a file fragment containing a reference to the next store path in the sequence.

To show why derivation package has a build-time rather than runtime dependency on derivation dependency , use --derivation.

Options

•

--all / -a

Show all edges in the dependency graph leading from package to dependency , rather than just a shortest path.

•

--precise

For each edge in the dependency graph, show the files in the parent that cause the dependency.

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 .

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.

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.

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.

•

--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

•

--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.

Note

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