{
  description = "Colmena hive configuration.";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-23.05";
    framework = {
      url = "path:./framework";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    phobos = {
      url = "path:./phobos";
      inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = { nixpkgs, framework, phobos, ... }:
    let
      system = "x86_64-linux";
    in
    {
      colmena = {
        meta = {
          nixpkgs = import nixpkgs { inherit system; };
          specialArgs = { inherit system; };
        };

        # Local machines. Deploy using `colmena apply-local [--sudo]`

        framework = {
          imports = [ framework.nixosModules.default ];
          deployment = {
            allowLocalDeployment = true;
            targetHost = null;  # Disable SSH deployment.
          };
        };

        # Remote machines. Deploy using `colmena apply`

        phobos = phobos.nixosModules.default;
      };
    };
}