Warning: This program is experimental and its interface is subject to change.
Name
nix build
- build a derivation or fetch a store path
Synopsis
nix build
[option...] installables...
Examples
-
Build the default package from the flake in the current directory:
# nix build
-
Build and run GNU Hello from the
nixpkgs
flake:# nix build nixpkgs#hello # ./result/bin/hello Hello, world!
-
Build GNU Hello and Cowsay, leaving two result symlinks:
# nix build nixpkgs#hello nixpkgs#cowsay # ls -l result* lrwxrwxrwx 1 … result -> /nix/store/v5sv61sszx301i0x6xysaqzla09nksnd-hello-2.10 lrwxrwxrwx 1 … result-1 -> /nix/store/rkfrm0z6x6jmi7d3gsmma4j53h15mg33-cowsay-3.03+dfsg2
-
Build a specific output:
# nix build nixpkgs#glibc.dev # ls -ld ./result-dev lrwxrwxrwx 1 … ./result-dev -> /nix/store/dkm3gwl0xrx0wrw6zi5x3px3lpgjhlw4-glibc-2.32-dev
-
Build attribute
build.x86_64-linux
from (non-flake) Nix expressionrelease.nix
:# nix build -f release.nix build.x86_64-linux
-
Build a NixOS system configuration from a flake, and make a profile point to the result:
# nix build --profile /nix/var/nix/profiles/system \ ~/my-configurations#nixosConfigurations.machine.config.system.build.toplevel
(This is essentially what
nixos-rebuild
does.) -
Build an expression specified on the command line:
# nix build --impure --expr \ 'with import <nixpkgs> {}; runCommand "foo" { buildInputs = [ hello ]; } "hello > $out"' # cat ./result Hello, world!
Note that
--impure
is needed because we're using<nixpkgs>
, which relies on the$NIX_PATH
environment variable. -
Fetch a store path from the configured substituters, if it doesn't already exist:
# nix build /nix/store/rkfrm0z6x6jmi7d3gsmma4j53h15mg33-cowsay-3.03+dfsg2
Description
nix build
builds the specified installables. Installables that
resolve to derivations are built (or substituted if possible). Store
path installables are substituted.
Unless --no-link
is specified, after a successful build, it creates
symlinks to the store paths of the installables. These symlinks have
the prefix ./result
by default; this can be overridden using the
--out-link
option. Each symlink has a suffix -<N>-<outname>
, where
N is the index of the installable (with the left-most installable
having index 0), and outname is the symbolic derivation output name
(e.g. bin
, dev
or lib
). -<N>
is omitted if N = 0, and
-<outname>
is omitted if outname = out
(denoting the default
output).
Options
-
--dry-run
Show what this command would do without doing it. -
--json
Produce output in JSON format, suitable for consumption by another program. -
--no-link
Do not create symlinks to the build results. -
--out-link
/-o
path
Use path as prefix for the symlinks to the build results. It defaults toresult
. -
--profile
path
The profile to update. -
--rebuild
Rebuild an already built package and compare the result to the existing store paths.
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. -
--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 list of locations used to look up<...>
file names. -
--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).
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.