anchor.diff:  
   in stdenv.mkDerivation rec {
     name = "pulseaudio-modules-bt-${version}";
  -  version = "unstable-2019-03-15";
  +  version = "1.1.99";
   
     src = fetchFromGitHub {
       owner = "EHfive";
       repo = "pulseaudio-modules-bt";
  -    rev = "0b397c26eb4fd5dc611bd3e2baa79776de646856";
  -    sha256 = "09q0xh9iz0crik6xpln9lijirf62aljxa1jrds1i1zgflyfidd0z";
  -    fetchSubmodules = true;
  +    rev = "v${version}";
  +    sha256 = "0x670xbd62r3fs9a8pa5p4ppvxn6m64hvlrqa702gvikcvyrmwcg";
     };
   
     patches = [
  
positive.code:     for so in $out/lib/pulse-${pulseaudio.version}/modules/*.so; do
        orig_rpath=$(patchelf --print-rpath "$so")
        patchelf \
          --set-rpath "${lib.getLib ffmpeg_4}/lib:$out/lib/pulse-${pulseaudio.version}/modules:$orig_rpath" \
          "$so"
      done
    '';
  
negative.code:     ffmpeg_4
      fdk_aac
      libtool
      ldacbt
      bluez
      dbus
      sbc
  