R""( # Examples * Build the default package from the flake in the current directory: ```console # nix build ``` * Build and run GNU Hello from the `nixpkgs` flake: ```console # nix build nixpkgs#hello # ./result/bin/hello Hello, world! ``` * Build GNU Hello and Cowsay, leaving two result symlinks: ```console # 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 GNU Hello and print the resulting store path. ```console # nix build nixpkgs#hello --print-out-paths /nix/store/v5sv61sszx301i0x6xysaqzla09nksnd-hello-2.10 ``` * Build a specific output: ```console # nix build nixpkgs#glibc.dev # ls -ld ./result-dev lrwxrwxrwx 1 … ./result-dev -> /nix/store/dkm3gwl0xrx0wrw6zi5x3px3lpgjhlw4-glibc-2.32-dev ``` * Build all outputs: ```console # nix build "nixpkgs#openssl^*" --print-out-paths /nix/store/gvad6v0cmq1qccmc4wphsazqbj0xzjsl-openssl-3.0.13-bin /nix/store/a07jqdrc8afnk8r6f3lnhh4gvab7chk4-openssl-3.0.13-debug /nix/store/yg75achq89wgqn2fi3gglgsd77kjpi03-openssl-3.0.13-dev /nix/store/bvdcihi8c88fw31cg6gzzmpnwglpn1jv-openssl-3.0.13-doc /nix/store/gjqcvq47cmxazxga0cirspm3jywkmvfv-openssl-3.0.13-man /nix/store/7nmrrad8skxr47f9hfl3xc0pfqmwq51b-openssl-3.0.13 ``` * Build attribute `build.x86_64-linux` from (non-flake) Nix expression `release.nix`: ```console # nix build --file release.nix build.x86_64-linux ``` * Build a NixOS system configuration from a flake, and make a profile point to the result: ```console # 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: ```console # nix build --impure --expr \ 'with import {}; runCommand "foo" { buildInputs = [ hello ]; } "hello > $out"' # cat ./result Hello, world! ``` Note that `--impure` is needed because we're using ``, which relies on the `$NIX_PATH` environment variable. * Fetch a store path from the configured substituters, if it doesn't already exist: ```console # nix build /nix/store/rkfrm0z6x6jmi7d3gsmma4j53h15mg33-cowsay-3.03+dfsg2 ``` # Description `nix build` builds the specified *installables*. [Installables](./nix.md#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 `--`, 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`). `-` is omitted if *N* = 0, and `-` is omitted if *outname* = `out` (denoting the default output). )""