anchor.diff:  
   stdenv.mkDerivation rec {
     pname = "libjcat";
  -  version = "0.1.7";
  +  version = "0.1.10";
   
     outputs = [ "bin" "out" "dev" "devdoc" "man" "installedTests" ];
   
  
positive.code:     gobject-introspection
      vala
      gtk-doc
      (python3.withPackages (pkgs: with pkgs; [
        setuptools
      ]))
    ];
  
    buildInputs = [
  
negative.code:     "-Dgtkdoc=true"
      "-Dinstalled_test_prefix=${placeholder "installedTests"}"
    ];
  
    doCheck = true;
  
  