Rachael Green worked on the envoyproxy/envoy repository, focusing on improving type-safety for WebAssembly (wasm) contexts within the codebase. She addressed a covariant type error by refactoring the Context class, updating the wasm() method to return a base pointer and introducing envoyWasm() for derived type access. This change aligned Envoy’s wasm context handling with updates in proxy-wasm-cpp-host, reducing header dependency risks and preventing cyclic dependencies. Using C++ and applying software architecture and refactoring skills, Rachael’s work enhanced the stability and maintainability of wasm-based extensions, ensuring compatibility and a smoother upgrade path for the proxy-wasm ecosystem.