Worked on improving the reliability and maintainability of quantum computing tools in the PennyLaneAI ecosystem, focusing on compiler development and simulation accuracy. In the catalyst repository, simplified the CustomCallOp API by converting the number_original_arg attribute from an array to a scalar integer, updating associated tests and ensuring CI validation to reduce complexity and clarify usage. In pennylane-lightning, addressed a bug affecting PauliRot execution when identity Pauli words are present, enhancing simulation correctness for identity-heavy circuits. Utilized C++, MLIR, and testing frameworks throughout, emphasizing robust intermediate representation manipulation and continuous integration alignment to support stable quantum circuit development workflows.