Reactive Streams is an initiative that aims to provide a standard for exchanging data streams across an asynchronous boundary. At the same time, it guarantees that the receiving side is not forced to buffer arbitrary amounts of data.

There are several available implementations of Reactive Stream, and we have already learned how you can feature Reactive Programming in Vert.x. In this chapter, we will complement our knowledge using the SmallRye Reactive Messaging implementation to show you how we can integrate it with a streaming platform such as Apache Kafka or a messaging broker such as ActiveMQ with minimal configuration changes.

To familiarize ourselves with MicroProfile Reactive Messaging, we need proper knowledge of some key concepts. First of all, MicroProfile Reactive Messaging is a specification that uses CDI beans to drive the flow...