Worked on the typst/typst repository to enhance backend reliability and HTML content processing. Over two months, addressed division overflow and negative floor semantics in the Calc module by refining Rust logic and expanding test coverage, which reduced runtime panics and ensured correct mathematical behavior. Later, implemented a robust update to HTML processing by restricting raw HTML tags to text-only content, introducing clear differentiation between raw and non-raw elements, and adding comprehensive validation tests. Collaborated closely with peers through code reviews and co-authored changes, demonstrating strong skills in Rust, backend development, and testing while improving maintainability and security of the codebase.