Nathan Gross contributed to both mozilla/gecko-dev and mozilla/application-services by delivering targeted improvements in browser and storage management. He implemented a new get_keys API in Rust for WebExtensions sync storage, enabling retrieval of all keys and enhancing reliability through comprehensive edge-case testing and changelog documentation. In JavaScript, Nathan corrected the lwtheme-brighttext attribute handling in Lightweight Theme, ensuring it functioned as a true boolean for greater consistency. His work emphasized robust API development, maintainable code, and thorough test coverage, resulting in improved correctness and developer ergonomics across both repositories. These contributions demonstrated depth in Rust, JavaScript, and storage systems.