Worked on enhancing type safety and maintainability in the gdsfactory/gdsfactory repository by addressing return type annotations in core component methods. Focused on the Copy and Dup methods, the update replaced ambiguous Self references with explicit concrete class types, reducing API ambiguity and improving downstream integration reliability. This change, implemented in Python using object-oriented programming principles and type hinting, improved static analysis and IDE autocomplete support for developers. The work was traceable through a dedicated commit and demonstrated attention to code quality and maintainability, ensuring that future development in the repository benefits from clearer, more robust type definitions in essential components.