Worked on the cedar-policy/cedar repository to deliver the Upsert Entities capability, enabling efficient addition and updating of entities within the policy engine’s Entities struct. The implementation involved refactoring internal Rust methods to support upsert operations and recomputing transitive closures after each upsert, ensuring data consistency across dependent policies. This feature enhanced policy management efficiency and laid groundwork for future scalability. The work focused on API design, data structures, and policy enforcement, with all changes documented in Markdown. No major bug fixes were reported during this period, as efforts were concentrated on robust feature delivery and internal code improvements.