Hi. I did the GenMQTT project that wraps an Erlang module called gen_emqtt that was written by Erlio for their VerneMQ MQTT broker. gen_emqtt used to be in a separate project called vmq_commons, but that project has been moved into the vernemq application, and hence the gen_emqtt is no longer available without getting the entire VerneMQ broker.
GenMQTT is thus deprecated, because I am not going to maintain the Erlang library, since it has some flaws—a proper error kernel being one of them. I am working on an implementation in pure Elixir, and I have some different approaches than Hulaaki. I don’t know how long this will take as I have a fulltime job that doesn’t relate to MQTT.
As for now I would recommend looking into both Hulaaki and GenMQTT; if you decide to go with GenMQTT I will happily accept pull requests.
