Niu Liu

Sep 23, 2026 · Backend Development

Ordered Messages Aren't Enough: Preventing State Regressions with Versioning and State Machines

The article explains why message ordering alone fails to prevent business state regressions, detailing how version gaps and unordered consumption cause issues, and presents solutions using event versioning, state machines, and proper Kafka/RocketMQ configuration to ensure correct order processing per order ID while allowing parallelism across orders.