anchor.diff:      cp broadcom/*.hcd "$out/lib/firmware/brcm"
     '';
   
  +  outputHashMode = "recursive";
  +  outputHashAlgo = "sha256";
  +  outputHash = "1gwzasl5w5nc0awqv3w2081ns63wd1yds0xh0dg95dc6brnqhhf8";
  +
     meta = with stdenv.lib; {
       description = "Firmware for builtin Wifi/Bluetooth devices in the Raspberry Pi 3 and Zero W";
       homepage = https://archive.raspberrypi.org/debian/pool/main/f/firmware-nonfree/;
  
positive.code:   # Firmware blobs do not need fixing and should not be modified
    dontFixup = true;
  
    # Unpack the debian package
    unpackCmd = ''
      if ! [[ "$curSrc" =~ \.deb$ ]]; then return 1; fi
      ar -xf "$curSrc"
      tar -xf data.tar.xz
    '';
  
    installPhase = ''
  
negative.code: { stdenv, fetchurl, dpkg }:
  
  stdenv.mkDerivation rec {
    name = "raspberrypi-wireless-firmware-${version}";
  