feat: split config more

modules/nixos/usecases/gaming.nix

@@ -0,0 +1,50 @@
+{
+  config,
+  lib,
+  pkgs,
+  username,
+  ...
+}:
+
+with lib;
+
+let
+  cfg = config.usecases.gaming;
+in
+{
+  options.usecases.gaming = {
+    enable = mkEnableOption "Enable gaming things";
+  };
+
+  config = mkIf cfg.enable {
+    programs.steam.enable = true;
+
+    services.udev.packages = with pkgs; [ oversteer ];
+    users.users.${username}.extraGroups = [
+      "wheel"
+      "input"
+    ];
+
+    environment.systemPackages = with pkgs; [
+      steam
+      oversteer
+      obs-studio
+      (lutris.override {
+        extraLibraries =
+          pkgs: with pkgs; [
+            libgudev
+            libvdpau
+            libsoup
+          ];
+      })
+      wine
+      winetricks
+      protontricks
+      mangohud
+      gamescope
+      gamemode
+      # fix for some proton games not launching without any error message
+      libxcrypt
+    ];
+  };
+}