During September 2025, François Trastour focused on improving the reliability of tile and terrain loading in the CesiumGS/cesium-native repository. He addressed a bug where custom HTTP headers, such as authentication tokens and API keys, were not consistently propagated to all subfile requests, including .terrain files. By refining the network programming logic in C++ and updating documentation in Markdown, François ensured that secure access controls are maintained throughout the asset management workflow. This targeted fix prevents failed tile loads due to missing headers, enhancing both security and developer experience. His work demonstrated careful attention to correctness and maintainability in complex systems.