Worked on DSpace core and dspace-angular repositories to enhance data integrity and front-end performance. Introduced 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. Extended backend validation in Java and added comprehensive unit tests to ensure reliability across environments. On the front end, refactored item page logic in Angular and TypeScript to optimize browse definition retrieval, reducing redundant API requests and improving load times. Focused on robust database management, API integration, and cross-database compatibility, delivering three features with a strong emphasis on maintainability.