{ config, pkgs, pkgs-unstable, lib, nvidia, ... }:
let
in
{
  config = lib.mkIf nvidia.enable {
    environment.systemPackages = with pkgs; [
      lshw
      nvtopPackages.full
      glxinfo
      (pkgs.writeShellScriptBin "nvidia-offload" ''
        export __NV_PRIME_RENDER_OFFLOAD=1
        export __NV_PRIME_RENDER_OFFLOAD_PROVIDER=NVIDIA-G0
        export __GLX_VENDOR_LIBRARY_NAME=nvidia
        export __VK_LAYER_NV_optimus=NVIDIA_only
        exec "$@"
      '')
    ] ++ [
      # pkgs-unstable.nvtopPackages.intel
      # pkgs-unstable.nvtopPackages.nvidia
    ];

    # Load nvidia driver for Xorg and Wayland
    services.xserver.videoDrivers = [ "nvidia" ];

    hardware = {
      nvidia = {
        prime = lib.mkIf nvidia.prime {
          intelBusId = "PCI:0:2:0";
          nvidiaBusId = "PCI:1:0:0";
          offload = {
            enable = true;
            enableOffloadCmd = true;
          };
        };
        modesetting.enable = true;

        # Modesetting is required.

        # Nvidia power management. Experimental, and can cause sleep/suspend to fail.
        # Enable this if you have graphical corruption issues or application crashes after waking
        # up from sleep. This fixes it by saving the entire VRAM memory to /tmp/ instead 
        # of just the bare essentials.
        powerManagement.enable = true;

        # Fine-grained power management. Turns off GPU when not in use.
        # Experimental and only works on modern Nvidia GPUs (Turing or newer).
        powerManagement.finegrained = true;

        # Use the NVidia open source kernel module (not to be confused with the
        # independent third-party "nouveau" open source driver).
        # Support is limited to the Turing and later architectures. Full list of 
        # supported GPUs is at: 
        # https://github.com/NVIDIA/open-gpu-kernel-modules#compatible-gpus 
        # Only available from driver 515.43.04+
        # Currently alpha-quality/buggy, so false is currently the recommended setting.
        open = false;

        # Enable the Nvidia settings menu,
        # accessible via `nvidia-settings`.
        nvidiaSettings = true;

        # Optionally, you may need to select the appropriate driver version for your specific GPU.
        package = config.boot.kernelPackages.nvidiaPackages.stable;
      };
      opengl = {
        enable = true;
        driSupport = true;
        driSupport32Bit = true;
      };
    };
  };
}