Astrowu focused on backend development for the AutoMQ/automq repository, where he enhanced the s3stream module by delivering comprehensive unit test coverage for the WALCallbackSequencer class. Using Java and unit testing frameworks, he validated edge cases such as handling empty queues after processing requests and ensured correct behavior of the tryFree method for both empty and non-empty queues. His work also addressed exception handling in the before method and verified after-method behavior when processing requests with unexpected offsets. This targeted effort reduced regression risk, improved code reliability, and strengthened the maintainability of production workloads dependent on WAL sequencing logic.