cdec_json_serialization:
  https://github.com/pks/cdec-dtrain-legacy
  branch json_serial @c3f3891a9c146483b63f3d903f9971438850bbad

gperftools:
  https://code.google.com/p/gperftools-git/
  master @e54971d58641853a9515d9f0313645729eab113a

json-cpp:
  https://github.com/ascheglov/json-cpp.git
  master @4eb4b47cf4d622bc7bf34071d6b68fc5beb37051

msgpack-c:
  https://github.com/msgpack/msgpack-c.git
  master @156a4403ab625e05ac6988cc6eac9877e407794e