Event-Driven Infrastructure Pattern

System diagram

Architectural overview

Producers emit domain events to a central bus; consumers process asynchronously. Decouples services and enables audit trails, replay, and new consumers without changing producers.

Tradeoffs

• Eventual consistency; avoid using events for synchronous, strict consistency requirements.
• Schema evolution and versioning require discipline.

Scaling considerations

Partition topics by key (e.g. account_id). Scale consumers with consumer groups. Retain events for replay and audit; compact or archive by policy.

Common pitfalls

• Using events for request-response; use APIs for that.
• No idempotent handling, so duplicate events cause duplicate side effects.