The message server needs libvws built with libuv support. Start it, then drive it with the messaging client of Chapter 4, A Messaging Client:

$ ./server-message
server-message: vrtql_msg echo server on ws://127.0.0.1:8181/websocket (Ctrl-C to stop)

Each structured message the client sends is echoed back in the same serialisation format. Press Ctrl-C to stop the server.