use proton-ge

tundra/home.nix

···
       signal-desktop
       typst
       wl-clipboard
-      mangohud
-      gamescope
     ];
 
     stateVersion = "26.05";

tundra/programs.nix

···
       remotePlay.openFirewall = true;
       dedicatedServer.openFirewall = true;
       localNetworkGameTransfers.openFirewall = true;
+			extraCompatPackages = with pkgs; [
+				proton-ge-bin
+			];
+			extraPackages = with pkgs; [
+				gamescope
+				mangohud
+			];
     };
   };
   services = {