Over a two-month period, this developer delivered core backend features for the UBB-SE-2025-924-1 and UBB-SE-2025-Steam repositories, focusing on scalable user management, in-game store functionality, and robust news management APIs. They designed and implemented Entity Framework Core-based data models, RESTful controllers, and repository patterns using C# and SQL, establishing foundational CRUD operations and role-based access control. Their work included comprehensive unit testing with XUnit, interface-based repository mocks for improved test isolation, and database migrations to support initial schema and data seeding. The approach emphasized modularity, maintainability, and test reliability, enabling safer releases and efficient feature iteration.