Top 5 Things Every Apache Kafka Developer Should Know

This post introduces the sticky partitioner for Kafka producers, which improves batching efficiency by assigning records to the same partition until the batch is full or a timeout occurs, leading to fewer produce requests and reduced latency. It also explains the cooperative rebalancing protocol for consumer groups, which minimizes downtime during rebalances by shifting coordination logic to the broker-side group coordinator. Additionally, it details message delivery and durability guarantees configurable via the `acks` setting and `min.insync.replicas`, and highlights the utility of record headers for passing metadata and debugging information.