{
  description = "Zentralwerk network";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs";
    zentralwerk-network-key.url = "git+https://gitea.c3d2.de/zentralwerk/network.git?dir=nix/key&ref=nix";
  };

  outputs = { self, nixpkgs, zentralwerk-network-key }:
    let
      system = "x86_64-linux";
      systems = [ system ];
      forAllSystems = nixpkgs.lib.genAttrs systems;

      nixosConfig = name:
        nixpkgs.lib.nixosSystem {
          inherit system;
          modules = [ self.nixosModule ];
          extraModules = [ ({ ... }: {
            networking.hostName = name;
          }) ];
        };
    in
    rec {
      lib =
        import ./nix/lib {
          inherit self nixpkgs;
          inherit (zentralwerk-network-key.lib) gpgKey;
        };

      packages = forAllSystems (system:
        import ./nix/pkgs { inherit self nixpkgs system; }
      );

      nixosModule = { ... }: {
        imports = [ ./nix/nixos-module ];
      };

      nixosConfigurations =
        builtins.mapAttrs (hostName: _: nixosConfig hostName) (
          nixpkgs.lib.filterAttrs (_: { role, ... }:
            builtins.elem role [ "server" "container" ]
          ) lib.config.site.hosts
        );

      # nixosConfigurations.test_vm =
      #   nixpkgs.lib.nixosSystem {
      #     inherit system;
      #     modules = [ nixosModule ];
      #     extraModules = [ ({ ... }: {
      #       networking.hostName = "test_vm";
      #     }) ];
      #   };
    };
}