For one, it has message_id ackbacks so that you can have a request/response rpc style system. A basic feature for any websocket-heavy application. socket.s

For one, it has message_id ackbacks so that you can have a request/response rpc style system. A basic feature for any websocket-heavy application. socket.send('login', [uname, pass], (err) => ...) And there are socket-io clients for most languages that can interop with a socket-io server, once again supporting message_id callbacks. Reconciling my own message_id + reconnect buffer system is not something I want to build on the client + server every time I build an application. People talk shit about socket.io and then never recommend an alternative that implements this fundamental feature. Without message_ids, I get flashbacks to working with IMAP.