Koen Pauwels enhanced data integrity and front-end efficiency for the DSpace/DSpace and DSpace/dspace-angular repositories during January 2025. He enforced unique item ID constraints in both workspace and workspaceitem tables, implementing SQL migrations for H2 and PostgreSQL to clean up existing duplicates and prevent future ones. Using Java and SQL, he extended backend validation and added comprehensive unit tests to ensure reliability. On the front end, Koen refactored Angular components to optimize item page performance by reusing browse-definition fetches via RxJS, reducing redundant API calls. His work demonstrated depth in database management, backend development, and front-end optimization.