Worked on the FFmpeg/FFmpeg repository to deliver a targeted stability improvement for Windows ARM64EC builds by addressing a critical issue in .def file generation and symbol extraction. Focused on build systems and system programming, the work involved refining linker member formats and filtering symbols to ensure correct DLL generation and accurate symbol exports across ARM64EC and other architectures. Using C and Shell, the developer validated the fix through targeted ARM64EC Windows builds and symbol checks, reducing the risk of post-release maintenance. This contribution enhanced cross-architecture compatibility and improved the reliability of packaging for Windows ARM devices within the FFmpeg project.