During June 2025, this developer enhanced the uwislab/wuyu repository by implementing unique student number validation within the student management system. Using Java and leveraging backend development and database management skills, they introduced a retrieval-by-ID method and enforced uniqueness checks in the service layer. The solution throws an ApiException when duplicate student numbers are detected, directly addressing data integrity and reducing the risk of enrollment errors or data corruption. This focused change set improved governance and user trust, while also supporting future reporting needs. The work demonstrated a methodical approach to backend validation and contributed to safer, more reliable data flows.