nix3-develop(1)

    Warning
    This program is experimental (../../contributing/experimental-features.md#xp-feature-nix-command) and its interface is subject to change.

Name

nix develop - run a bash shell that provides the build environment of a derivation

Synopsis

nix develop [option…] installable

Note: this command’s interface is based heavily around installables (./nix.md#installables) , which you may want to read about first (nix --help).

Examples

•   Start a shell with the build environment of the default package of the flake in the current directory:

    # nix develop

    Typical commands to run inside this shell are:

    # configurePhase
    # buildPhase
    # installPhase

    Alternatively, you can run whatever build tools your project uses directly, e.g. for a typical Unix project:

    # ./configure --prefix=$out
    # make
    # make install

•   Run a particular build phase directly:

    # nix develop --unpack
    # nix develop --configure
    # nix develop --build
    # nix develop --check
    # nix develop --install
    # nix develop --installcheck

•   Start a shell with the build environment of GNU Hello:

    # nix develop nixpkgs#hello

•   Record a build environment in a profile:

    # nix develop --profile /tmp/my-build-env nixpkgs#hello

•   Use a build environment previously recorded in a profile:

    # nix develop /tmp/my-build-env

•   Replace all occurrences of the store path corresponding to glibc.dev with a writable directory:

    # nix develop --redirect nixpkgs#glibc.dev ~/my-glibc/outputs/dev

    Note that this is useful if you’re running a nix develop shell for nixpkgs#glibc in ~/my-glibc and want to compile another package against it.

•   Run a series of script commands:

    # nix develop --command bash -c "mkdir build && cmake .. && make"

Description

nix develop starts a bash shell that provides an interactive build environment nearly identical to what Lix would use to build installable (./nix.md#installables) . Inside this shell, environment variables and shell functions are set up so that you can interactively and incrementally build your package.

Nix determines the build environment by building a modified version of the derivation installable that just records the environment initialised by stdenv and exits. This build environment can be recorded into a profile using --profile.

The prompt used by the bash shell can be customised by setting the bash-prompt, bash-prompt-prefix, and bash-prompt-suffix settings in nix.conf or in the flake’s nixConfig attribute.

Flake output attributes

If no flake output attribute is given, nix develop tries the following flake output attributes:

•   devShells.<system>.default

•   packages.<system>.default

If a flake output name is given, nix develop tries the following flake output attributes:

•   devShells.<system>.<name>

•   packages.<system>.<name>

•   legacyPackages.<system>.<name>

Options

•   --build (#opt-build) Run the build phase.

•   --check (#opt-check) Run the check phase.

•   --command (#opt-command) / -c command args Instead of starting an interactive shell, start the specified command and arguments.

•   --configure (#opt-configure) Run the configure phase.

•   --ignore-environment (#opt-ignore-environment) / -i Clear the entire environment (except those specified with --keep).

•   --install (#opt-install) Run the install phase.

•   --installcheck (#opt-installcheck) Run the installcheck phase.

•   --keep (#opt-keep) / -k name Keep the environment variable name.

•   --phase (#opt-phase) phase-name The stdenv phase to run (e.g. build or configure).

•   --profile (#opt-profile) path The profile to operate on.

•   --redirect (#opt-redirect) installable outputs-dir Redirect a store path to a mutable location.

•   --unpack (#opt-unpack) Run the unpack phase.

•   --unset (#opt-unset) / -u name Unset the environment variable name.

Common evaluation options:

•   --arg (#opt-arg) name expr Pass the value expr as the argument name to Nix functions.

•   --argstr (#opt-argstr) name string Pass the string string as the argument name to Nix functions.

•   --debugger (#opt-debugger) Start an interactive environment if evaluation fails.

•   --eval-store (#opt-eval-store) store-url The URL of the Nix store (../../command-ref/new-cli/nix3-help-stores.md#store-url-format) to use for evaluation, i.e. to store derivations (.drv files) and inputs referenced by them.

•   --impure (#opt-impure) Allow access to mutable paths and repositories.

•   --include (#opt-include) / -I path Add path to the Nix search path. The Nix search path is initialized from the colon-separated NIX_PATH (../../command-ref/env-common.md#env-NIX_PATH) environment variable, and is used to look up the location of Nix expressions using paths (../../language/values.md#type-path) enclosed in angle brackets (i.e., <nixpkgs>).

    For instance, passing

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

    will cause Lix 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 Lix 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 Lix 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 (../nix-channel.md) ) can be abbreviated as channel:<channel-name>. For instance, the following two flags are equivalent:

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

    You can also fetch source trees using flake URLs (./nix3-flake.md#url-like-syntax) 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 (#opt-override-flake) original-ref resolved-ref Override the flake registries, redirecting original-ref to resolved-ref.

Common flake-related options:

•   --commit-lock-file (#opt-commit-lock-file) Commit changes to the flake’s lock file.

•   --inputs-from (#opt-inputs-from) flake-url Use the inputs of the specified flake as registry entries.

•   --no-registries (#opt-no-registries) Don’t allow lookups in the flake registries. This option is deprecated; use --no-use-registries.

•   --no-update-lock-file (#opt-no-update-lock-file) Do not allow any updates to the flake’s lock file.

•   --no-write-lock-file (#opt-no-write-lock-file) Do not write the flake’s newly generated lock file.

•   --output-lock-file (#opt-output-lock-file) flake-lock-path Write the given lock file instead of flake.lock within the top-level flake.

•   --override-input (#opt-override-input) input-path flake-url Override a specific flake input (e.g. dwarffs/nixpkgs). This implies --no-write-lock-file.

•   --reference-lock-file (#opt-reference-lock-file) flake-lock-path Read the given lock file instead of flake.lock within the top-level flake.

Logging-related options:

•   --debug (#opt-debug) Set the logging verbosity level to ‘debug’.

•   --log-format (#opt-log-format) format Set the format of log output; one of raw, internal-json, bar, bar-with-logs, multiline or multiline-with-logs.

•   --print-build-logs (#opt-print-build-logs) / -L Print full build logs on standard error.

•   --quiet (#opt-quiet) Decrease the logging verbosity level.

•   --verbose (#opt-verbose) / -v Increase the logging verbosity level.

Miscellaneous global options:

•   --help (#opt-help) Show usage information.

•   --offline (#opt-offline) Disable substituters and consider all previously downloaded files up-to-date.

•   --option (#opt-option) name value Set the Lix configuration setting name to value (overriding nix.conf).

•   --refresh (#opt-refresh) Consider all previously downloaded files out-of-date.

•   --repair (#opt-repair) During evaluation, rewrite missing or corrupted files in the Nix store. During building, rebuild missing or corrupted store paths.

•   --version (#opt-version) Show version information.

Options that change the interpretation of installables (../../command-ref/new-cli/nix.md#installables) :

•   --expr (#opt-expr) / -E expr Interpret installables (../../command-ref/new-cli/nix.md#installables) as attribute paths relative to the Nix expression expr.

•   --file (#opt-file) / -f file Interpret installables (../../command-ref/new-cli/nix.md#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 (../../command-ref/conf-file.md#command-line-flags) for overriding configuration settings with command line flags.