anchor.diff:  , libxml2
   , glib
   , wrapGAppsNoGuiHook
  -, vala
   , sqlite
   , libxslt
   , libstemmer
  
positive.code:   nativeBuildInputs = [
      meson
      ninja
      vala
      pkg-config
      asciidoc
      gettext
  
negative.code: 
  stdenv.mkDerivation rec {
    pname = "tracker";
    version = "3.4.0.beta";
  
    outputs = [ "out" "dev" "devdoc" ];
  
    src = fetchurl {
      url = "mirror://gnome/sources/${pname}/${lib.versions.majorMinor version}/${pname}-${version}.tar.xz";
      sha256 = "r7evHXAHaELU6Fg691l6qJG9phTqiyjmAwiT/gxSpiE=";
    };
  
    postPatch = ''
  