anchor.diff:        glib libiconv libintl
       ] ++ lib.optional (atLeast "0.38") graphviz
         ++ extraBuildInputs;
  +
  +    doCheck = false; # fails, requires dbus daemon
   
       meta = with stdenv.lib; {
         description = "Compiler for GObject type system";
  
positive.code: { stdenv, lib, fetchurl, pkgconfig, flex, bison, libxslt, autoconf, graphviz
  , glib, libiconv, libintl, libtool, expat
  }:
  
  
negative.code:   let
      atLeast = lib.versionAtLeast "${major}.${minor}";
    in stdenv.mkDerivation rec {
      name = "vala-${version}";
      version = "${major}.${minor}";
  
      src = fetchurl {
        url = "mirror://gnome/sources/vala/${major}/${name}.tar.xz";
        inherit sha256;
      };
  
      postPatch = ''
        patchShebangs tests
      '';
  
      outputs = [ "out" "devdoc" ];
  
  