hardware.firmware = [
      (
       let driverPkg = builtins.fetchurl {
           url = "https://mpow.s3-us-west-1.amazonaws.com/20201202_mpow_BH456A_driver+for+Linux.7z";
           sha256 = "25de05daaecbc698504e3b87f14cf24dd6cec97551ce3f2b720f5e559919d98b";
       };
       in
       pkgs.runCommandNoCC "firmware-rtl8761b" { } ''
       ${pkgs.p7zip}/bin/7z e ${driverPkg}
       mkdir -p $out/lib/firmware/rtl_bt
       cp rtl8761b_config $out/lib/firmware/rtl_bt/rtl8761b_config.bin
       cp rtl8761b_fw $out/lib/firmware/rtl_bt/rtl8761b_fw.bin
       ''
      )
  ];