Worked on backend robustness for the openai/codex and zed-industries/codex repositories, focusing on improving error handling in Rust. Addressed issues where missing token_usage data in /compact API responses could cause crashes or inconsistent behavior. Refactored the response event logic to gracefully handle absent token_usage fields, ensuring that both repositories maintained consistent and reliable API behavior. Emphasized cross-repository standardization by aligning error handling approaches, which improved maintainability and reduced the risk of runtime failures. Utilized Rust and backend development skills to deliver targeted bug fixes, prioritizing stability and consistency over new feature development during this period of focused engineering work.