Worked on the potiuk/airflow repository to deliver an enhancement for EMR Serverless job cancellation, focusing on improving the reliability and maintainability of workflow triggers. Developed a new asynchronous on_kill() method in Python to ensure that EMR Serverless jobs are cancelled only in response to user-initiated actions, streamlining the cancellation process and reducing unnecessary failures. Refactored the backend logic by removing obsolete handlers and simplifying the cancellation flow, which improved code clarity and maintainability. Updated unit tests to directly verify the new behavior, leveraging asynchronous programming and backend development skills to align the workflow with user expectations and business needs.