Worked on the nodejs/node repository to enhance serialization stability by addressing a bug in the handling of V8 ExternalPointers within InterceptorInfo. Focused on ensuring that serialization and deserialization processes functioned correctly without promoting InterceptorInfo to a read-only space, thereby improving the reliability of core data structures. Applied a targeted V8 upstream patch using cherry-pick and supplemented the fix with regression tests to validate the new behavior. Utilized C++ and deep knowledge of V8 engine internals, along with robust testing practices, to strengthen the serialization path and maintain long-term stability for Node.js core development workflows.