Worked on stabilizing topic compaction for null-value tombstones across the datastax/pulsar and apache/pulsar repositories, focusing on backend reliability and data integrity. Addressed bugs where non-batched null-value messages were not properly removed during compaction, updating the logic for payload size and key extraction to ensure accurate cleanup. Added comprehensive tests to validate tombstone behavior and aligned compaction processes across both codebases for consistency. Leveraged Java for backend development and testing, delivering changes that improved storage efficiency and broker reliability. The work demonstrated careful attention to cross-repository collaboration and robust validation of message compaction involving null-value scenarios.