anchor.diff:  
     propagatedBuildInputs = [ glib gtk3 p11-kit ];
   
  -  checkInputs = [ python2 ];
  +  checkInputs = [ python3 ];
     doCheck = false; # fails 21 out of 603 tests, needs dbus daemon
   
     #enableParallelBuilding = true; issues on hydra
  
positive.code: { stdenv, fetchurl, pkgconfig, intltool, gnupg, p11-kit, glib
  , libgcrypt, libtasn1, dbus-glib, gtk3, pango, gdk-pixbuf, atk
  , gobject-introspection, makeWrapper, libxslt, vala, gnome3
  , python2 }:
  
  stdenv.mkDerivation rec {
    pname = "gcr";
    version = "3.28.1";
  
    src = fetchurl {
      url = "mirror://gnome/sources/${pname}/${stdenv.lib.versions.majorMinor version}/${pname}-${version}.tar.xz";
      sha256 = "12qn7mcmxb45lz1gq3s3b34rimiyrrshkrpvxdw1fc0w26i4l84m";
    };
  
    passthru = {
  
negative.code: 
    outputs = [ "out" "dev" ];
  
    nativeBuildInputs = [ pkgconfig gettext gobject-introspection libxslt makeWrapper vala ];
  
    buildInputs = let
      gpg = gnupg.override { guiSupport = false; }; # prevent build cycle with pinentry_gnome
  