Worked on the google/dawn repository to deliver a feature that customizes DXGI Alt+Enter fullscreen behavior, enabling applications to implement their own fullscreen toggle logic instead of relying on DXGI’s default handling. The approach involved disabling built-in fullscreen management and ensuring correct swapchain lifecycle integration by coordinating MakeWindowAssociation calls with the appropriate DXGIFactory. Collaboration included importing an external pull request to align with upstream changes, maintaining traceability through detailed commit references. The work emphasized stability and cross-repository coordination, utilizing C++ and leveraging expertise in DirectX, Windows API, and graphics programming to support downstream application flexibility and maintainable fullscreen transitions.