Qinyuhang Xiaoxiang contributed to the oxc-project/oxc repository by developing and refining lint rules for Jest and Vitest, focusing on improving test assertion clarity and consistency. Using Rust and leveraging skills in linter development and test automation, Qinyuhang implemented rules that enforce best practices for test timing assertions, such as preferring toHaveBeenCalledTimes over toHaveLength and standardizing single-call assertions. Additionally, Qinyuhang addressed a transformer bug to ensure correct replacement of import.meta properties, adding targeted unit tests to validate the fix. The work demonstrated a thoughtful approach to code quality and maintainability within a complex Rust-based codebase.