Learn our story how we discovered RxJS, how it helped to bring SaleMove from a massive state machine into an elegant event-based reactive platform. We started out with a big state machine that was difficult to maintain, test and develop. As the application grew we quickly saw that another approach was needed. After discovering RxJS, we quickly adopted the event-based reactive approach. In this talk I am going to give you an overview of RxJS and why should you use it. I am going to talk about how once we adopted the event-based approach, it completely changed the way we think about state and state programming. All this with code examples.