Distributed systems speak in different ways, yet commands, events, and streams are often mixed together and misused as if they were interchangeable. When communication styles are misunderstood, message brokers become overloaded with responsibilities they were never designed for, leading to unnecessary complexity, performance degradation, lost features, and often functional and technical issues.

This session introduces a deeper explanation of how distributed systems communicate. Messages express intent, asking the system to perform work. Events express facts, describing something that has already happened. Streams represent ordered histories that can be replayed and reprocessed over time. Treating these communication styles as the same thing creates fragile architectures. Using real customer scenarios, we explore how each communication style maps naturally to different architectural backbones, what goes wrong when meaning and backbone do not align, and how communication choices directly influence system capabilities and constraints.

Attendees leave with a clearer understanding of messages, events, and streams, along with concrete decision criteria to avoid accidental complexity before it hardens into technical debt.