Worked on the cloudflare/workerd repository, focusing on improving the reliability of JavaScript RPC target validation. Addressed a specific bug by refining the guard logic to ensure that the superclass check is only enforced when a wrapperModule is not present, which prevents unnecessary errors in non-RPC scenarios. This targeted fix reduced error noise and improved the stability of end-to-end workflows. The work involved careful error handling and explicit condition checks, contributing to clearer and more maintainable code paths. Utilized C++ for the implementation, applying skills in API development and robust error management to enhance the maintainability and reliability of the codebase.