Backpressure is very hard topic. One way is to use one of the
http://www.reactive-streams.org/ implementations, but that means all things Rx, which is not really nice for many cases. There are also issues in their approach, search for rx streams criticism. For one, it doesn’t have backpressure propagation facilities from outbound connection (someone loading huge page via very slow mobile connection), and then if pressure is high and it needs propagation to clients (some sort of webpage or mobile polling json, or WS connection sending too many updates, etc), it doesn’t have means to do so as well. But I’m no expert in this area, will need to research it one day.