Messaging Event-Driven

Event-Driven Architecture

Systems communicate by emitting and reacting to events, enabling fanout, resilience, and evolution over time.

Events are facts

Model immutable “what happened” records; derive state from events when useful.

Loose coupling

Producers don’t know consumers; schemas and contracts become critical.

Async boundaries

Failures become retries, DLQs, and compensations—not simple rollbacks.

Observability

Trace IDs, idempotency keys, and event lineage make debugging possible.