N2O

N2O is an Erlang library that relays messages for WebSocket, MQTT and TCP servers. Its core runs a loop that routes each request through a ring of virtual nodes and a set of managed processes, and it ships optional session storage, BERT and JSON encoders, and message-bus backends. The project describes normal use as a web framework or web application server over WebSockets. An application adds the library as a dependency with the mad build tool, and the package is published on Hex. The project’s documentation also covers a Nitrogen web framework protocol module and a business process engine protocol module.

Worth knowing

The README gives the license as ISC, but the LICENSE file in the repository is the DHARMA License, so a reader needs to check which terms apply before reuse.