Web sockets and HTTP/2 give us a bidirectional, fully duplex method to send messages between the server and a web browser. The question is: what are we going to do with it, and how? Enterprise messaging isn't cool, but synchronous RPC isn't cool either. Now that we have a great messaging abstraction pub/sub is cool, but how do we go about building an actual application? What the abstractions I should build, and how do I go about building them? If we don't reinvent REST over a websocket, what should we invent? This talk will discuss messaging and a world without REST, drawing on my experience building real time trading systems based on the same fundamental concepts now generally available to everyone.