{
  config,
  lib,
  pkgs,
  ...
}:
let
  cfg = config.hardware;
in
{

  imports = [
    (lib.mkRenamedOptionModule
      [ "networking" "enableRT73Firmware" ]
      [ "hardware" "enableRedistributableFirmware" ]
    )
    (lib.mkRenamedOptionModule
      [ "networking" "enableIntel3945ABGFirmware" ]
      [ "hardware" "enableRedistributableFirmware" ]
    )
    (lib.mkRenamedOptionModule
      [ "networking" "enableIntel2100BGFirmware" ]
      [ "hardware" "enableRedistributableFirmware" ]
    )
    (lib.mkRenamedOptionModule
      [ "networking" "enableRalinkFirmware" ]
      [ "hardware" "enableRedistributableFirmware" ]
    )
    (lib.mkRenamedOptionModule
      [ "networking" "enableRTL8192cFirmware" ]
      [ "hardware" "enableRedistributableFirmware" ]
    )
  ];

  ###### interface

  options = {

    hardware.enableAllFirmware = lib.mkEnableOption "all firmware regardless of license";

    hardware.enableRedistributableFirmware =
      lib.mkEnableOption "firmware with a license allowing redistribution"
      // {
        default = config.hardware.enableAllFirmware;
        defaultText = lib.literalExpression "config.hardware.enableAllFirmware";
      };

    hardware.wirelessRegulatoryDatabase =
      lib.mkEnableOption "loading the wireless regulatory database at boot"
      // {
        default = cfg.enableRedistributableFirmware || cfg.enableAllFirmware;
        defaultText = lib.literalMD "Enabled if proprietary firmware is allowed via {option}`enableRedistributableFirmware` or {option}`enableAllFirmware`.";
      };

  };

  ###### implementation

  config = lib.mkMerge [
    (lib.mkIf (cfg.enableAllFirmware || cfg.enableRedistributableFirmware) {
      hardware.firmware =
        with pkgs;
        [
          linux-firmware
          intel2200BGFirmware
          rtl8192su-firmware
          rt5677-firmware
          rtl8761b-firmware
          zd1211fw
          alsa-firmware
          sof-firmware
          libreelec-dvb-firmware
        ]
        ++ lib.optional pkgs.stdenv.hostPlatform.isAarch raspberrypiWirelessFirmware;
    })
    (lib.mkIf cfg.enableAllFirmware {
      assertions = [
        {
          assertion = !cfg.enableAllFirmware || pkgs.config.allowUnfree;
          message = ''
            the list of hardware.enableAllFirmware contains non-redistributable licensed firmware files.
              This requires nixpkgs.config.allowUnfree to be true.
              An alternative is to use the hardware.enableRedistributableFirmware option.
          '';
        }
      ];
      hardware.firmware =
        with pkgs;
        [
          broadcom-bt-firmware
          b43Firmware_5_1_138
          b43Firmware_6_30_163_46
          xow_dongle-firmware
        ]
        ++ lib.optionals pkgs.stdenv.hostPlatform.isx86 [
          facetimehd-calibration
          facetimehd-firmware
        ];
    })
    (lib.mkIf cfg.wirelessRegulatoryDatabase {
      hardware.firmware = [ pkgs.wireless-regdb ];
    })
  ];
}