In March 2025, SJ Lee focused on improving Windows compatibility in the apache/hadoop repository by addressing a critical issue with temporary directory creation. Lee implemented a solution that uses ACL-based permissions when POSIX permissions are unavailable, ensuring Hadoop can reliably create work directories on Windows systems. This approach enhanced cross-platform file system handling and reduced deployment friction for enterprise users. The work involved Java and Java NIO, with an emphasis on file system operations and robust testing. By adding targeted tests, Lee improved coverage and helped prevent regressions, demonstrating a thoughtful, end-to-end approach to platform-specific reliability challenges.