refactor

modules/nixos/apps/dolphin/default.nix

@@ -0,0 +1,18 @@
+{ options, config, lib, pkgs, ... }:
+
+with lib;
+with lib.plusultra;
+let cfg = config.plusultra.apps.dolphin;
+in
+{
+  options.plusultra.apps.dolphin = with types; {
+    enable = mkBoolOpt false "Whether or not to enable Dolphin.";
+  };
+
+  config = mkIf cfg.enable {
+    environment.systemPackages = with pkgs; [ dolphin-emu ];
+
+    # Enable GameCube controller support.
+    services.udev.packages = [ pkgs.dolphinEmu ];
+  };
+}