nixos-config/system/gamemode.nix

{ config, pkgs, inputs, ... }: {
  programs.gamemode.enable = true;
  programs.gamemode.enableRenice = true;
  programs.gamemode.settings = {
    general = { renice = 10; };

    # Warning: GPU optimisations have the potential to damage hardware
    gpu = {
      apply_gpu_optimisations = "accept-responsibility";
      gpu_device = 0;
      amd_performance_level = "high";
    };

    custom = {
      start = "${pkgs.libnotify}/bin/notify-send 'GameMode started'";
      end = "${pkgs.libnotify}/bin/notify-send 'GameMode ended'";
    };
  };
}