Worked on the mozilla/gecko-dev repository to enhance the reliability of the JIT compiler’s on-stack replacement (OSR) path. Focused on resolving issues with the REALM_INDEPENDENT flag when self_hosted_cache is enabled, addressing a subtle bug that could impact realm-independence and frame handling robustness. Utilized C++ and applied skills in compiler optimization, debugging, and JIT compilation to ensure that OSR’d frames correctly maintain their intended state. The targeted fix improved the stability and correctness of frame transitions within the JIT, reflecting a careful approach to low-level runtime behavior and contributing to the overall maintainability of the codebase.