{
  pkgs,
  lib,
  ...
}: {
  # nixpkgs.config.allowUnfreePredicate = pkg:
  #   builtins.elem (lib.getName pkg) [
  #     "steam"
  #     "steam-original"
  #     "steam-unwrapped"
  #     "steam-run"
  #   ];
  nixpkgs.overlays = [
    (self: super: {
      lutris = super.lutris.overrideAttrs (final: prev: {
        # WARNING: pkgs.mbedtls_2 is marked insecure!
        # Replace pkgs.mbedtls_2 (v2.28.10) with pkgs.mbedtls (v3.6.4)
        targetPkgs = pkgs: (
          (builtins.filter (p: p != pkgs.mbedtls_2) (prev.targetPkgs pkgs))
          ++ [pkgs.mbedtls]
        );
      });
    })
  ];

  programs = {
    steam = {
      enable = true;
      gamescopeSession.enable = false; # .desktop entry for gamescope

      remotePlay.openFirewall = true;
      dedicatedServer.openFirewall = true;
      localNetworkGameTransfers.openFirewall = true;

      extraCompatPackages = with pkgs; [
        proton-ge-bin
      ];
    };

    gamemode.enable = true;
  };

  environment.systemPackages = with pkgs; [
    steamcmd

    mangohud
    protonup-qt

    # XXX: DEBUG: disable lutris
    # XXX: NOTE: pkgs.lutris depends on pkgs.mbedtls_2 which is marked insecure!
    # XXX: NOTE: Use the provided overlay to patch pkgs.mbedtls_2 -> pkgs.mbedtls
    # lutris

    bottles
    heroic
  ];
}