anchor.diff:  { stdenv, fetchurl, pkgconfig, dbus, glib, alsaLib,
  -  pythonPackages, readline, libsndfile, udev, libical,
  +  pythonPackages, readline, udev, libical,
     systemd, enableWiimote ? false }:
   
   assert stdenv.isLinux;
  
positive.code:             list-devices \
              monitor-bluetooth \
              ; do
        ln -s ../test/$a $out/bin/bluez-$a
      done
      popd
      wrapPythonProgramsIn $test/test "$test/test $pythonPath"
  
negative.code: 
    makeFlags = "rulesdir=$(out)/lib/udev/rules.d";
  
    postInstall = ''
      mkdir -p $test/{bin,test}
      cp -a test $test
      pushd $test/test
      for a in \
  