Andrew Norton refactored the ObjectCache API in the facebook/CacheLib repository, focusing on enabling tiered caching strategies. He converted key ObjectCache methods, including getConfiguredTtl, to static functions using C++ and object-oriented design principles. This approach decoupled cache operations from specific object instances, allowing for a unified API that simplifies downstream integration and accelerates adoption of tiered caches across services. By reducing coupling and improving testability, Andrew’s work made it easier to implement unit tests and mocks. The changes established a more maintainable API contract, laying the groundwork for future enhancements in CacheLib’s tiered caching layer.