Event-Driven Architecture with Spring Boot and AWS EventBridge: Escaping the Distributed Monolith

Many microservice migrations simply replace a local monolith with a distributed one by relying on synchronous HTTP calls. Event-Driven Architecture (EDA) using choreography — where services publish facts rather than issue commands — breaks this pattern. Using AWS EventBridge as a serverless event bus, Spring Boot services only need to know one endpoint, while EventBridge handles routing to any number of consumers. Key production concerns covered include: event schema versioning and contract management (treating events as immutable APIs), implementing idempotency via tracked event IDs within database transactions to handle at-least-once delivery, and distributed tracing with OpenTelemetry or AWS X-Ray to maintain observability across async boundaries.