anchor.diff:  { stdenv, fetchurl, glib, flex, bison, pkgconfig, libffi, python
  -, libintlOrEmpty, cctools, cairo
  +, libintlOrEmpty, cctools, cairo, gnome3
   , substituteAll, nixStoreDir ? builtins.storeDir
   }:
   # now that gobjectIntrospection creates large .gir files (eg gtk3 case)
  
positive.code:     })
    ];
  
    meta = with stdenv.lib; {
      description = "A middleware layer between C libraries and language bindings";
      homepage    = http://live.gnome.org/GObjectIntrospection;
  
negative.code: # In that case its about 6MB which could be separated
  
  let
    pname = "gobject-introspection";
    version = "1.54.1";
  in
  with stdenv.lib;
  stdenv.mkDerivation rec {
    name = "${pname}-${version}";
  
    src = fetchurl {
      url = "mirror://gnome/sources/${pname}/${gnome3.versionBranch version}/${name}.tar.xz";
      sha256 = "0zl7pfkzkm07733391b4f3cwjbnvb1nwvpmajf5bajh6bxgfv3dq";
    };
  
  