Aiden Romero Garcia contributed to the IT-Academy-BCN/ita-challenges-backend repository by enhancing backend modularity and maintainability over a one-month period. He redistributed core functions into a new controller, implemented comprehensive unit tests using JUnit and Mockito, and improved test coverage for bookmarks and favorites. Working primarily in Java with the Spring Framework and MongoDB, Aiden addressed legacy code issues by cleaning up ghost changes and normalizing error messages. His efforts included scaffolding new repository components and refining documentation, which reduced technical debt and improved code hygiene. The work delivered measurable improvements in test reliability and long-term backend maintainability.