April 2026 monthly summary for the spring-pulsar project. Focused on improving reliability of transactional message listener tests and ensuring test expectations match runtime behavior under common configuration. Delivered a targeted test stabilization in the DefaultPulsarMessageListenerContainerTxnTests and tightened traceability around the fix for easier maintenance and review.

March 2026: Stability improvement for the Spring Kafka consumer pause in the async acknowledgment flow. Addressed the issue where the consumer could pause indefinitely due to unacked offsets by introducing a containsUnackedOffset check, refining the while-loop condition, and adding focused tests. This work reduces stall risk, improves consumer throughput, and enhances reliability for high-throughput streaming apps. Documentation updates accompany the change, and the fix was auto-cherry-picked to 4.0.x and 3.3.x for broader compatibility.

January 2026 monthly summary focused on reliability improvements in message processing for spring-kafka. Implemented a critical fix for asynchronous acknowledgment gap handling in the Kafka listener container, addressing offset gaps larger than 1. This included changes to the acknowledgment logic and targeted tests to verify correct behavior, reducing the risk of out-of-order commits and message loss in high-throughput scenarios. The work also included ensuring cross-version readiness via auto-cherry-picks to 4.0.x and 3.3.x branches.