Apache Kafka 4.2.0 Release Announcement

Apache Kafka 4.2 introduces several new features and improvements, enhancing its functionality, security, and observability. Key updates include the production readiness of Kafka Queues (Share Groups) with new processing features, advancements in Kafka Streams such as server-side rebalance protocol and dead letter queue support, and improvements in consistency with standardized command-line arguments and metric naming conventions. Security is bolstered with an allowlist connector client configuration policy, while thread-safety improvements address concurrency risks. The release also adds support for Java 25, external schema support in JsonConverter, dynamic configuration for remote log manager thread pools, and rack ID exposure in the Admin API. Deprecation notices for features set for removal in Apache Kafka 5.0 are also highlighted, ensuring users are informed of upcoming changes. The update is a result of contributions from a wide community of developers, reflecting a collaborative effort to advance the capabilities of Apache Kafka.