Worked on a targeted refactor in the facebook/fbthrift repository to enhance user ID handling for FreeBasicServicesViewerContext. The approach involved moving the FreeBasicServicesViewerContext check from ThriftContextPropState to its caller, resulting in clearer control flow and improved maintainability of the backend logic. By centralizing the user ID check, the change reduced code duplication and minimized the risk of misalignment across components. The work was implemented using PHP and Thrift, focusing on backend development best practices. This maintenance-driven update laid the groundwork for easier future enhancements to user identity handling, contributing to better code quality and traceability within the service.