Pipes is a framework we use at Fajurion to handle real-time messaging for our chat app. It works across multiple nodes with multiple servers for ultimate scalability. It currently works with UDP and WebSockets. There is still some need for performance improvements in the future, but it will be fine for small applications.
There is also no documentation as of writing this, there'll eventually be a documentation page for this API, but that'll happen when it is fully released.