anchor.diff:  stdenv.mkDerivation rec {
     name = "gtk+-${version}";
     versionMajor = "3.20";
  -  versionMinor = "5";
  +  versionMinor = "6";
     version = "${versionMajor}.${versionMinor}";
   
     src = fetchurl {
       url = "mirror://gnome/sources/gtk+/${versionMajor}/${name}.tar.xz";
       sha256Url = "mirror://gnome/sources/gtk+/${versionMajor}/${name}.sha256sum";
  -    sha256 = "9790b0267384904ad8a08e7f16e5f9ff1c4037de57788d48d1eaf528355b1564";
  +    sha256 = "3f8016563a96b1cfef4ac9e795647f6316deb2978ff939b19e4e4f8f936fa4b2";
     };
   
     nativeBuildInputs = [
       gettext
  +    makeWrapper
       perl
     ];
   
  
positive.code: { stdenv
  , fetchurl
  , gettext
  , perl
  
  , at-spi2-atk
  
negative.code: 
    postInstall = "rm -rvf $out/share/gtk-doc";
  
    preFixup = ''
      wrapProgram $out/bin/gtk3-demo-application \
        --prefix 'XDG_DATA_DIRS' : "$GSETTINGS_SCHEMAS_PATH"
  
      wrapProgram $out/bin/gtk3-widget-factory \
        --prefix 'XDG_DATA_DIRS' : "$GSETTINGS_SCHEMAS_PATH"
    '';
  
    passthru = {
      inherit
  