anchor.diff: -{ stdenv, lib, fetchurl, pkgconfig, flex, bison, libxslt, autoconf, graphviz
  +{ stdenv, lib, fetchurl, pkgconfig, flex, bison, libxslt, autoconf, automake, graphviz
   , glib, libiconv, libintl, libtool, expat
   }:
   
  
positive.code:       glib libiconv libintl
      ] ++ lib.optional (atLeast "0.38") graphviz
        ++ extraBuildInputs;
  
      meta = with stdenv.lib; {
        description = "Compiler for GObject type system";
  
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" ];
  
  