During November 2024, Berk Yavuz focused on backend development and refactoring within the xupefei/delta repository, delivering a targeted improvement to checkpoint metadata loading reliability. He refactored the loadMetadataFromFile function by extracting its core parsing logic into a new private method, unsafeLoadMetadataFromFile, and removed an unused method to streamline the codebase. This approach improved the separation of concerns between parsing and exception handling, enhancing both maintainability and testability of checkpoint processing in Spark-based workflows. Working primarily with Scala, Berk demonstrated depth in backend engineering and codebase hygiene, addressing reliability and clarity in a critical component of the project.