During February 2026, cmiracle focused on stabilizing MongoDB change data capture (CDC) heartbeat handling within the apache/seatunnel repository. Addressing a recurring issue, cmiracle introduced a HEARTBEAT flag in the Java-based connector, ensuring heartbeat records were excluded from the main data-change processing path when heartbeat intervals were enabled. This targeted fix eliminated null pointer exceptions during heartbeat events, reducing runtime errors and support incidents. By leveraging Java, Kafka, and MongoDB, cmiracle improved the reliability and data accuracy of CDC pipelines. The work demonstrated a careful, defensive coding approach and a clear understanding of backend development in distributed data systems.