Wushengshijie refactored Aarch64 atomic macro implementations across the rust-lang/rust and rust-lang/compiler-builtins repositories, focusing on simplifying build systems and improving maintainability. By leveraging Rust’s macro programming capabilities and the unstable concat feature, they eliminated the need for build.rs-generated code, streamlining the build process and standardizing atomic code paths. Their work preserved full test coverage and core logic, ensuring reliability while reducing complexity. This approach demonstrated a strong command of Rust, low-level programming, and compiler internals, and laid a foundation for easier future maintenance and architecture support within the Rust ecosystem. The work reflected thoughtful, in-depth engineering.