event-driven-architect

Event-driven architecture decouples microservices by using asynchronous messaging. Define domain events, select a message broker like Kafka or RabbitMQ, implement event sourcing to store state changes, and apply CQRS to separate read and write models for scalability and resilience.

Event sourcing stores all state changes as immutable events rather than overwriting current state. You reconstruct application state by replaying events, enabling complete audit trails, temporal queries, and recovery from any point in time without separate backup systems.

Use Saga patterns when coordinating transactions across multiple microservices without a centralized transaction manager. Sagas break distributed work into compensating steps, ensuring eventual consistency and handling failures gracefully in event-driven systems.

Kafka excels at high-throughput event streaming with durable replay and real-time data pipelines; RabbitMQ offers flexible routing and lower latency for traditional messaging. Choose Kafka for event sourcing and analytics; RabbitMQ for transactional workflows and simpler topologies.

Yes, CQRS and event sourcing complement each other. Events populate separate read models optimized for queries while commands drive event generation. This pattern scales read and write paths independently and enables real-time projections from event streams.

Model your domain events and commands clearly, understand eventual consistency trade-offs, and have messaging infrastructure (Kafka or RabbitMQ) operational. Team familiarity with asynchronous patterns and monitoring distributed systems is essential.