Contributed to the typeorm/typeorm repository by expanding the query builder’s capabilities, introducing support for nested joins and new Author and Post entities. Focused on enhancing cross-database compatibility, particularly for PostgreSQL and SQLite, the work addressed complex join attribute handling, including edge cases involving brackets. The implementation involved updating and expanding test coverage to ensure regression safety and validate new features. Collaboration with other contributors was emphasized to reinforce code quality and review processes. Leveraged TypeScript, TypeORM, and database management skills to deliver a more robust and flexible query builder, supporting advanced relational queries and improving developer productivity.