During January 2026, Yizheng Zheng contributed to the martinvonz/jj repository by developing a divergent() function within the revset language, enabling users to identify and manage divergent commits more effectively. This addition addressed the challenge of handling complex version histories and facilitated safer merges. Yizheng also improved backend maintainability by simplifying the ChangeIdIndexImpl::resolve_prefix logic, removing redundant checks to enhance code clarity and runtime efficiency. Working primarily in Rust and focusing on backend development and version control, Yizheng’s work demonstrated a thoughtful approach to both feature delivery and codebase health, with an emphasis on maintainability and collaborative workflows.