Development

This section describes how to properly import extensions. For examples of creating extensions, study the source code of existing extensions.

Importing

First, decide how many extensions and files you want to import.

If you have multiple extensions, or they are split across files:

delib.callExtensions {
  paths = [./foo ./default.nix]; # default: []
  exclude = [./foo/test.nix];    # default: []
  recursive = true;              # default: true
}
# Returns an attrset where the keys are extension names and the values are the extensions themselves.

If you have a single extension represented by one file:

delib.callExtension ./default.nix
# Returns a single extension.

Distributing

To make your extensions available for use in other flakes, add the denixExtensions attrset to outputs:

outputs = {denix, ...}: {
  denixExtensions = denix.lib.callExtensions {
    paths = [./extensions];
  };
};

You can also create a separate flake that contains only extensions:

flake.nix

{
  description = "Denix extensions collection";

  inputs.denix.url = "github:yunfachi/denix";

  outputs =
    { denix, ... }:
    {
      denixExtensions = denix.lib.callExtensions {
        paths = [ ./extensions ];
      };
    };
}

You can use a template for this:

nix flake init -t github:yunfachi/denix#extensions-collection

If you want to use denixExtensions in the same flake that contains your configuration, refer to self:

outputs = {denix, self, ...}: let
  mkConfigurations = moduleSystem:
    # ...
    denix.lib.configurations {
      extensions = with denix.lib.extensions; with self.denixExtensions; [
        args # denix.lib.extensions
        awesomeExtension # self.denixExtensions
      ];
    };
in {
  denixExtensions = denix.lib.callExtensions {paths = [./extensions];};
};