Case studies
End-to-end financial system scenarios, tying together topic topology, key choice, idempotency, retry, DLQ, replay, and observability.
- PIX received
Topic topology, key choice, idempotency, retry, DLQ, replay, and observability in a PIX-receiving flow.
- Card purchase
Synchronous authorization, and a single event consumed independently by antifraud, notifications, cashback, and analytics.
- Statement processing
High volume concentrated in a short window, partitioning for real parallelism, consumer lag under a peak, and idempotency in batch reprocessing.
- Index rebuild
A bug in the consumer feeding Elasticsearch corrupts the search index; the fix involves a full replay via a new Consumer Group.
- Integrating with an unstable external system
Timeout, retry with backoff, circuit breaker, and DLQ protecting a consumer that depends on an unreliable external API.