anchor.diff:    optDbus_cplusplus = shouldUsePkg dbus_cplusplus;
     optAlsaLib = shouldUsePkg alsaLib;
     optPyqt4 = shouldUsePkg pyqt4;
  +  optPythonDBus = shouldUsePkg pythonDBus;
     optXdg_utils = shouldUsePkg xdg_utils;
   in
   stdenv.mkDerivation rec {
  
positive.code:       LIBDIR=$out/lib INCLUDEDIR=$out/include install
    '' else ''
      scons PREFIX=$out PYPKGDIR=$PYDIR UDEVDIR=$out/lib/udev/rules.d install
  
      wrapProgram $out/bin/ffado-mixer --prefix PYTHONPATH : \
        $PYTHONPATH:$PYDIR:${pyqt4}/$LIBSUFFIX:${pythonDBus}/$LIBSUFFIX:
      wrapProgram $out/bin/ffado-diag --prefix PYTHONPATH : \
        $PYTHONPATH:$PYDIR:$out/share/libffado/python:${pyqt4}/$LIBSUFFIX:${pythonDBus}/$LIBSUFFIX:
    '';
  
    meta = with stdenv.lib; {
  
negative.code:   ] ++ stdenv.lib.optionals (!libOnly) [
      optLibjack2 optDbus optDbus_cplusplus optAlsaLib optPyqt4
      optXdg_utils
    ];
  
    patches = [ ./build-fix.patch ];
  