Integration Exercise (High-Speed Coding)

Implement a small integration exercise: based on provided interface/data-source contracts, quickly fetch/transform/aggregate data and output results in the required format. Typical requirements: consume multiple inputs (e.g., multiple endpoints, two tables, or JSON/CSV blobs) join by keys handle missing/duplicate/out-of-order data output in a specified format Note: The post lacks the concrete contracts and I/O, so this remains a high-level summary only.