anchor.diff:  , pkgconfig , ncurses, xapian_1_2_22, gpgme, utillinux, fetchpatch, tzdata, icu, libffi
   , cmake, libssh2, openssl, mysql, darwin, git, perl, pcre, gecode_3, curl
   , libmsgpack, qt48, libsodium, snappy, libossp_uuid, lxc, libpcap, xorg, gtk2, buildRubyGem
  -, cairo, re2, rake, gobjectIntrospection, gdk_pixbuf
  +, cairo, re2, rake, gobjectIntrospection, gdk_pixbuf, zeromq, graphicsmagick
   }@args:
   
   let
  
positive.code:   };
  
    ffi = attrs: {
    nativeBuildInputs = [ pkgconfig ];
      buildInputs = [ libffi ];
    };
  
  
negative.code:   };
  
    rmagick = attrs: {
      nativeBuildInputs = [ pkgconfig ];
      buildInputs = [ imagemagick which ];
    };
  
  