Apple IMEI Status Check API

I need a clean, well-documented REST API that takes an Apple device IMEI and sends back three pieces of information—FMI status, SIM lock status, and Blacklist status—in a single JSON response. The same service also has to accept bulk requests, so a user can upload a small CSV or TXT file and receive the results as a consolidated JSON array.

For the single-IMEI flow, a straightforward POST/GET endpoint is fine; for bulk, a multipart upload or presigned URL approach will work as long as the caller receives a job ID and can poll for completion. Either way, responses must remain consistent in structure and include sensible error codes for invalid or unsupported IMEIs.

Speed and reliability matter more to me than the underlying language, but keep dependencies modern and mainstream—Python (FastAPI), Node (Express), Go, or similar. If you rely on a third-party data source, confirm it provides up-to-date and legitimately licensed Apple activation data, and wrap any external calls behind retry logic so the API stays stable.

Deliverables
- Source code with clear setup instructions (Docker preferred)
- Postman or cURL examples for single and bulk calls
- Brief README covering authentication, rate limits, and expected JSON schema
- A short change log so I can track future improvements

I’ll test by sending a mix of valid and dummy IMEIs and comparing your output with known ground truth. If everything lines up and the API remains responsive under a small stress test, we’re done.