made some progress

modules/nixos/desktop/default.nix

@@ -0,0 +1,37 @@
+{ lib, config, namespace, ... }:let
+  inherit (lib) mkOption mkMerge attrNames filterAttrs;
+  inherit (lib.types) nullOr enum bool;
+
+  cfg = config.${namespace}.desktop;
+in
+{
+  options.${namespace}.desktop = {
+    use = mkOption {
+      type = nullOr enum (attrNames (filterAttrs (n: type == "directory") (readDir ./.)));
+      default = null;
+      example = "plasma";
+      description = "Which desktop to enable";
+    };
+
+    autoLogin = mkOption {
+      type = bool;
+      default = false;
+      example = true;
+      description = "Enable plasma's auto login feature.";
+    };
+  };
+
+  config = mkMerge [
+    (mkIf cfg.desktop != null {
+      "${namespace}".desktop.${cfg.use}.enable = true;
+
+      services.displayManager = {
+        enable = true;
+        
+        autoLogin = mkIf cfg.autoLogin {
+          enable = true;
+        };
+      };
+    })
+  ];
+}

modules/nixos/desktop/gamescope/default.nix

@@ -0,0 +1,27 @@
+{ lib, config, namespace, inputs, ... }:let
+  inherit (lib) mkEnableOption;
+
+  cfg = config.${namespace}.desktop.gamescope;
+in
+{
+  imports = [ inputs.jovian.nixosModules.default ];
+
+  options.${namespace}.desktop.gamescope = {
+    enable = mkEnableOption "Enable Steamdeck ui";
+  };
+
+  config = mkIf cfg.enable {
+    "${namespace}".desktop.kde.enable = true;
+
+    jovian = {
+      steam = {
+        enable = true;
+        autoStart = true;
+        user = "chris";
+        updater.splash = "steamos";
+        desktopSession = "plasma";
+      };
+      steamos.useSteamOSConfig = true;
+    };
+  };
+}

modules/nixos/desktop/gnome/default.nix

@@ -0,0 +1,14 @@
+{ lib, config, namespace, ... }:let
+  inherit (lib) mkEnableOption mkOption;
+  inherit (lib.types) bool;
+
+  cfg = config.${namespace}.desktop.gnome;
+in
+{
+  options.${namespace}.desktop.gnome = {
+    enable = mkEnableOption "Enable Gnome";
+  };
+
+  config = mkIf cfg.enable {
+  };
+}

modules/nixos/desktop/plasma/default.nix

@@ -0,0 +1,30 @@
+{ lib, config, namespace, ... }:let
+  inherit (lib) mkEnableOption mkOption;
+  inherit (lib.types) bool;
+
+  cfg = config.${namespace}.desktop.plasma;
+in
+{
+  options.${namespace}.desktop.plasma = {
+    enable = mkEnableOption "Enable KDE Plasma";
+  };
+
+  config = mkIf cfg.enable {
+    environment.plasma6.excludePackages = with pkgs.kdePackages; [ konsole kate ghostwriter oxygen ];
+    environment.sessionVariables.NIXOS_OZONE_WL = "1";
+
+    services = {
+      xserver.enable = false;
+
+      desktopManager.plasma6.enable = true;
+
+      displayManager = {
+        defaultSession = "plasma";
+        sddm = {
+          enable = true;
+          wayland.enable = true;
+        };
+      };
+    };
+  };
+}