diff --git a/flake.lock b/flake.lock
index df275aa..be9a746 100644
--- a/flake.lock
+++ b/flake.lock
@@ -358,6 +358,44 @@
         "type": "github"
       }
     },
+    "millennium": {
+      "inputs": {
+        "millennium-src": "millennium-src",
+        "nixpkgs": "nixpkgs"
+      },
+      "locked": {
+        "dir": "packages/nix",
+        "lastModified": 1784860807,
+        "narHash": "sha256-nznQFS9H8er9bTwxKG4LSa2D0lGsxIPUqDuWa1rbJkA=",
+        "owner": "SteamClientHomebrew",
+        "repo": "Millennium",
+        "rev": "266e41ea8924c41e51145ae986a9bdf68f9415d9",
+        "type": "github"
+      },
+      "original": {
+        "dir": "packages/nix",
+        "owner": "SteamClientHomebrew",
+        "repo": "Millennium",
+        "type": "github"
+      }
+    },
+    "millennium-src": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1783268941,
+        "narHash": "sha256-MJLJ0I48HXgfOpISTAbDMYMUdWj9A6M+jGQz4uAvwyw=",
+        "owner": "SteamClientHomebrew",
+        "repo": "Millennium",
+        "rev": "f37f05bdbd4727d873a1ad83ce72d062ef9a0c48",
+        "type": "github"
+      },
+      "original": {
+        "owner": "SteamClientHomebrew",
+        "repo": "Millennium",
+        "rev": "f37f05bdbd4727d873a1ad83ce72d062ef9a0c48",
+        "type": "github"
+      }
+    },
     "niri": {
       "inputs": {
         "niri-stable": "niri-stable",
@@ -422,7 +460,7 @@
         "cachyos-kernel-patches": "cachyos-kernel-patches",
         "flake-compat": "flake-compat",
         "flake-parts": "flake-parts",
-        "nixpkgs": "nixpkgs"
+        "nixpkgs": "nixpkgs_2"
       },
       "locked": {
         "lastModified": 1785004507,
@@ -463,7 +501,7 @@
       "inputs": {
         "flake-compat": "flake-compat_2",
         "flake-parts": "flake-parts_2",
-        "nixpkgs": "nixpkgs_2",
+        "nixpkgs": "nixpkgs_3",
         "nixpkgs-nixcord": "nixpkgs-nixcord"
       },
       "locked": {
@@ -502,17 +540,17 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1784966893,
-        "narHash": "sha256-WCrs/9bdH+gzSZit3UrSa4sWdyZ8+uC5x5bymPgBHMg=",
-        "owner": "NixOS",
+        "lastModified": 1781577229,
+        "narHash": "sha256-lrp67w8AulE9Ks53n27I45ADSzbOCn4H+CNW1Ck8B+8=",
+        "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "328e42b4f861ae88cf3643962ed5c4ff918f2ba8",
+        "rev": "567a49d1913ce81ac6e9582e3553dd90a955875f",
         "type": "github"
       },
       "original": {
-        "owner": "NixOS",
-        "ref": "nixos-unstable-small",
+        "owner": "nixos",
         "repo": "nixpkgs",
+        "rev": "567a49d1913ce81ac6e9582e3553dd90a955875f",
         "type": "github"
       }
     },
@@ -579,6 +617,22 @@
       }
     },
     "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1784966893,
+        "narHash": "sha256-WCrs/9bdH+gzSZit3UrSa4sWdyZ8+uC5x5bymPgBHMg=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "328e42b4f861ae88cf3643962ed5c4ff918f2ba8",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable-small",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_3": {
       "locked": {
         "lastModified": 1784432872,
         "narHash": "sha256-n3gKTBIV4ZA5VQpUakffBe3KGu4+mhPoA34rrqS0GkA=",
@@ -594,7 +648,7 @@
         "type": "github"
       }
     },
-    "nixpkgs_3": {
+    "nixpkgs_4": {
       "locked": {
         "lastModified": 1784796856,
         "narHash": "sha256-wWFrV5/Qbm+lyt5x20E/bSbfJiGKMo4RCxZV8cl/WZI=",
@@ -610,7 +664,7 @@
         "type": "github"
       }
     },
-    "nixpkgs_4": {
+    "nixpkgs_5": {
       "locked": {
         "lastModified": 1784007870,
         "narHash": "sha256-djcLt/JJphyNt4eDY9XTly+/WbCK5lqWq9lSgCmJkkQ=",
@@ -696,7 +750,7 @@
       "inputs": {
         "flake-parts": "flake-parts_4",
         "git-hooks-nix": "git-hooks-nix",
-        "nixpkgs": "nixpkgs_4",
+        "nixpkgs": "nixpkgs_5",
         "treefmt-nix": "treefmt-nix"
       },
       "locked": {
@@ -732,12 +786,13 @@
       "inputs": {
         "disko": "disko",
         "home-manager": "home-manager",
+        "millennium": "millennium",
         "niri": "niri",
         "nix-cachyos-kernel": "nix-cachyos-kernel",
         "nix-vscode-extensions": "nix-vscode-extensions",
         "nixcord": "nixcord",
         "nixos-hardware": "nixos-hardware",
-        "nixpkgs": "nixpkgs_3",
+        "nixpkgs": "nixpkgs_4",
         "noctalia": "noctalia",
         "nur": "nur",
         "pedantix": "pedantix",
diff --git a/flake.nix b/flake.nix
index 7e0e690..be9da71 100644
--- a/flake.nix
+++ b/flake.nix
@@ -10,6 +10,7 @@
       inputs.nixpkgs.follows = "nixpkgs";
       url = "github:nix-community/home-manager";
     };
+    millennium.url = "github:SteamClientHomebrew/Millennium?dir=packages/nix";
     niri = {
       inputs.nixpkgs.follows = "nixpkgs";
       url = "github:sodiboo/niri-flake";
diff --git a/home/desktop/niri.nix b/home/desktop/niri.nix
index 807e60f..e5a517d 100644
--- a/home/desktop/niri.nix
+++ b/home/desktop/niri.nix
@@ -1,6 +1,7 @@
 {
   config,
   lib,
+  pkgs,
   ...
 }: {
   options.modules.desktop.niri.enable = lib.mkOption {
@@ -12,15 +13,16 @@
   config = lib.mkIf config.modules.desktop.niri.enable {
     programs.niri.settings = {
       environment = {
+        ELECTRON_OZONE_PLATFORM_HINT = "auto";
         NIXOS_OZONE_WL = "1";
+        QT_QPA_PLATFORM = "wayland";
         QT_QPA_PLATFORMTHEME = "qt6ct";
+        QT_WAYLAND_DISABLE_WINDOWDECORATION = "1";
       };
-
       hotkey-overlay = {
         hide-not-bound = true;
         skip-at-startup = true;
       };
-
       input = {
         keyboard = {
           numlock = true;
@@ -36,7 +38,6 @@
           tap = true;
         };
       };
-
       layer-rules = [
         {
           matches = [{namespace = "^noctalia-wallpaper*";}];
@@ -47,7 +48,6 @@
           matches = [{namespace = "^notification$";}];
         }
       ];
-
       layout = {
         default-column-width.proportion = 1.0;
         empty-workspace-above-first = true;
@@ -63,8 +63,10 @@
           top = 8;
         };
       };
-
       prefer-no-csd = true;
+      spawn-at-startup = [
+        {command = ["${pkgs.xwayland-satellite}/bin/xwayland-satellite"];}
+      ];
     };
   };
 }
diff --git a/home/desktop/xdg.nix b/home/desktop/xdg.nix
index c72a38a..f62eee5 100644
--- a/home/desktop/xdg.nix
+++ b/home/desktop/xdg.nix
@@ -16,6 +16,7 @@
         config.common.default = ["gtk"];
         enable = true;
         extraPortals = [pkgs.xdg-desktop-portal-gtk];
+        xdgOpenUsePortal = true;
       };
     };
   };
diff --git a/modules/hardware.nix b/modules/hardware.nix
index faf5162..a032c3c 100644
--- a/modules/hardware.nix
+++ b/modules/hardware.nix
@@ -4,7 +4,12 @@
   ...
 }: {
   config = lib.mkMerge [
-    {hardware.graphics.enable = true;}
+    {
+      hardware.graphics = {
+        enable = true;
+        enable32Bit = true;
+      };
+    }
     (lib.mkIf config.modules.desktop.enable {
       hardware.bluetooth.enable = true;
     })
diff --git a/modules/steam.nix b/modules/steam.nix
new file mode 100644
index 0000000..4603749
--- /dev/null
+++ b/modules/steam.nix
@@ -0,0 +1,42 @@
+{
+  config,
+  lib,
+  pkgs,
+  inputs,
+  username,
+  ...
+}: {
+  options.modules.apps.steam.enable = lib.mkOption {
+    default = config.modules.desktop.enable;
+    description = "Whether to enable Steam (with Millennium).";
+    type = lib.types.bool;
+  };
+
+  config = lib.mkIf config.modules.apps.steam.enable {
+    environment.sessionVariables = {
+      PROTON_ENABLE_WAYLAND = "1";
+      PROTON_USE_WAYLAND = "1";
+      SDL_VIDEODRIVER = "wayland,x11";
+      SDL_VIDEO_DRIVER = "wayland,x11";
+    };
+    programs = {
+      gamemode.enable = true;
+      gamescope = {
+        enable = true;
+        args = [
+          "--rt"
+          "--expose-wayland"
+        ];
+        capSysNice = false;
+      };
+      steam = {
+        enable = true;
+        package = inputs.millennium.packages.${pkgs.stdenv.hostPlatform.system}.millennium-steam;
+        extraCompatPackages = [pkgs.proton-ge-bin];
+        gamescopeSession.enable = true;
+        protontricks.enable = true;
+      };
+    };
+    users.users.${username}.extraGroups = ["gamemode"];
+  };
+}