anchor.diff:    cargoBuildFlags = [
       "--no-default-features"
       "--features"
  -    "${stdenv.lib.optionalString withALSA "alsa_backend,"}${stdenv.lib.optionalString withPulseAudio "pulseaudio_backend,"}${stdenv.lib.optionalString withPortAudio "portaudio_backend,"}"
  +    "${stdenv.lib.optionalString withALSA "alsa_backend,"}${stdenv.lib.optionalString withPulseAudio "pulseaudio_backend,"}${stdenv.lib.optionalString withPortAudio "portaudio_backend,"}${stdenv.lib.optionalString withMpris "dbus_mpris,"}${stdenv.lib.optionalString withKeyring "dbus_keyring,"}"
     ];
   
     nativeBuildInputs = [ pkgconfig ];
  
positive.code: , withALSA ? true, alsaLib ? null
  , withPulseAudio ? false, libpulseaudio ? null
  , withPortAudio ? false, portaudio ? null
  }:
  
  rustPlatform.buildRustPackage rec {
  
negative.code:   buildInputs = [ openssl ]
      ++ stdenv.lib.optional withALSA alsaLib
      ++ stdenv.lib.optional withPulseAudio libpulseaudio
      ++ stdenv.lib.optional withPortAudio portaudio
      ++ stdenv.lib.optional (withMpris || withKeyring) dbus;
  
    doCheck = false;
  
  