Mahmudur Rahman focused on enhancing Android packaging security and reliability within the facebook/buck2 and facebook/buck2-prelude repositories. He developed automated package validators and audit tooling using Python, integrating them into Buck2’s build system to detect forbidden strings in APK and bundle contents. By extending these validators across both repositories, Mahmudur ensured consistent compliance checks during Android builds. He also addressed critical test failures by correcting variable usage and function wrapping in build scripts, improving test stability. His work demonstrated depth in Android development, build system engineering, and test automation, resulting in more secure, reliable, and maintainable Android release processes.