As the popularity of any event-driven application increases, the number of concurrent connections may increase. Applications that employ thread-per-client architecture, frustrate scalability by exhausting a server’s memory with excessive allocations and by exhausting a server’s CPU with excessive context-switching. One of obvious solutions, is exorcising blocking operations from such applications. Vert.x is event driven and non blocking toolkit, which may help you to achive this goal. In this talk, we are going to cover it’s core features and develop a primitive application using WebSockets, RxJava and Vert.x.