Yifan Fu enhanced the Azure/PyRIT repository by implementing static typing improvements across the authentication and analytics modules. Using Python and leveraging type hinting, Yifan refactored function signatures to include explicit return types and parameter annotations, which increased code clarity and enabled more robust static analysis. This work focused on software maintenance, reducing the risk of runtime type errors and laying the groundwork for safer future refactoring. Although no major bugs were addressed during this period, the changes improved maintainability and developer onboarding, while supporting better integration with linting and static analysis tools for ongoing code quality assurance.