anchor.diff:  
     buildInputs = [
       glib
  -    gobject-introspection
     ];
   
     checkInputs = [
  
positive.code:   pname = "graphene";
    version = "1.10.6";
  
    outputs = [ "out" "devdoc" "installedTests" ];
  
    src = fetchFromGitHub {
      owner = "ebassi";
  
negative.code:   ];
  
    mesonFlags = [
      "-Dgtk_doc=${lib.boolToString (stdenv.buildPlatform == stdenv.hostPlatform)}"
      "-Dintrospection=${if (stdenv.buildPlatform == stdenv.hostPlatform) then "enabled" else "disabled"}"
      "-Dinstalled_test_datadir=${placeholder "installedTests"}/share"
      "-Dinstalled_test_bindir=${placeholder "installedTests"}/libexec"
    ];
  