nix-config/overlays/srb2.nix

{
  nixpkgs.overlays = [
    (final: prev: {
      srb2 = prev.srb2.overrideAttrs (oldAttrs: {
        desktopItems = [
          (prev.makeDesktopItem rec {
            name = "Sonic Robo Blast 2";
            exec = oldAttrs.pname;
            icon = oldAttrs.pname;
            comment = oldAttrs.meta.description;
            desktopName = name;
            genericName = name;
            startupWMClass = ".srb2-wrapped";
            categories = [ "Game" ];
          })
        ];
      });
    })
  ];
}