Add KDE desktop module

modules/default.nix

@@ -2,6 +2,7 @@
   imports = [
     ./options.nix
     ./desktop/gnome.nix
+    ./desktop/kde.nix
     ./desktop/mimeapps.nix
     ./desktop/apps/qbittorrent.nix
     ./desktop/apps/slack.nix

modules/desktop/kde.nix

@@ -0,0 +1,31 @@
+{ config, lib, pkgs, ... }:
+
+let cfg = config.modules.desktop.kde;
+in {
+  options.modules.desktop.kde = {
+    enable = lib.mkOption {
+      default = false;
+      example = true;
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    services.xserver = {
+      enable = true;
+      displayManager.sddm = {
+        enable = true;
+        wayland.enable = true;
+      };
+      desktopManager.plasma5.enable = true;
+    };
+
+    user.packages = with pkgs; [
+    ];
+
+    environment.systemPackages = with pkgs; [
+      adw-gtk3
+    ];
+
+    home.services.gpg-agent.pinentryFlavor = "qt";
+  };
+}