fix/src/nix/run.md

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Examples

• Run the default app from the blender-bin flake:

  # nix run blender-bin
  

• Run a non-default app from the blender-bin flake:

  # nix run blender-bin#blender_2_83
  

  Tip: you can find apps provided by this flake by running nix flake show blender-bin.

• Run vim from the nixpkgs flake:

  # nix run nixpkgs#vim
  

  Note that vim (as of the time of writing of this page) is not an app but a package. Thus, Nix runs the eponymous file from the vim package.

• Run vim with arguments:

  # nix run nixpkgs#vim -- --help
  

Description

nix run builds and runs installable, which must evaluate to an app or a regular Nix derivation.

If installable evaluates to an app (see below), it executes the program specified by the app definition.

If installable evaluates to a derivation, it will try to execute the program <out>/bin/<name>, where out is the primary output store path of the derivation, and name is the first of the following that exists:

• The meta.mainProgram attribute of the derivation.
• The pname attribute of the derivation.
• The name part of the value of the name attribute of the derivation.

For instance, if name is set to hello-1.10, nix run will run $out/bin/hello.

Flake output attributes

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

• apps.<system>.default

• packages.<system>.default

If an attribute name is given, nix run tries the following flake output attributes:

• apps.<system>.<name>

• packages.<system>.<name>

• legacyPackages.<system>.<name>

Apps

An app is specified by a flake output attribute named apps.<system>.<name>. It looks like this:

apps.x86_64-linux.blender_2_79 = {
  type = "app";
  program = "${self.packages.x86_64-linux.blender_2_79}/bin/blender";
};

The only supported attributes are:

• type (required): Must be set to app.

• program (required): The full path of the executable to run. It must reside in the Nix store.

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