During November 2024, Leo contributed to the thiws24/equipli repository by enhancing backend maintainability and evolving the reservation API. He introduced a Maven-based code formatting system, integrating a new pom.xml to enforce consistent code style across backend modules, which supports long-term code quality. Leo also revised the reservation API, implementing an atomic long in Java to generate sequential reservation numbers and updating the endpoint path to /api/reservations. These changes were thoroughly documented in Markdown and XML, laying a foundation for reliable data integrity and future API versioning. The work demonstrated thoughtful backend development and attention to maintainable engineering practices.