During March 2026, Frédéric Parain enhanced debugging capabilities in the JetBrainsRuntime repository by implementing interpreter codelets assembly printing. He developed a C++ feature that enables InterpreterCodelets to emit their assembly code, providing deeper visibility into interpreter operations and facilitating faster diagnosis of low-level runtime issues. This targeted improvement focused on interpreter design and debugging, allowing developers to analyze performance and internal behavior more effectively. Frédéric collaborated closely with reviewers to ensure the instrumentation was both safe and maintainable. The work demonstrated depth in C++ development and runtime internals, addressing a specific need for improved observability without introducing instability.