anchor.diff:      })
     ];
   
  +  depsBuildBuild = [
  +    pkg-config
  +  ];
  +
     nativeBuildInputs = [
       pkg-config
  -    pkg-config-helper
       gettext
       glib
     ];
  
positive.code: 
    NIX_CFLAGS_COMPILE = "-DAVAHI_SERVICE_DIR=\"/etc/avahi/services\"";
  
    prePatch = ''
      substituteInPlace configure \
        --replace pkg-config "$PKG_CONFIG"
    '';
  
    preBuild = lib.optionalString stdenv.isDarwin ''
      sed -i '20 i\
      #define __APPLE_USE_RFC_2292' \
  
negative.code: 
  assert qt4Support -> qt4 != null;
  
  stdenv.mkDerivation rec {
    pname = "avahi${lib.optionalString withLibdnssdCompat "-compat"}";
    version = "0.8";
  