Unlike some of its peers, Hazelcast allows us to witness first hand a lot of internal state information. By registering listeners to be notified as events occur, we can further enhance our application not only in terms of functionality but also in resilience. By allowing our application to know when and what events are unfolding underneath it, we can add defensiveness to it—embracing the dynamic and destroyable nature of modern agile approaches to applications and infrastructure.

In the next chapter, we will move a little away from just data, and look at the distributed execution and task processing capabilities on offer.