Avatar upload event loop blocking
An AI built this FastAPI file-upload handler that hashes and stores avatars. Throughput is far below expectations and the event loop's lag metric is high even though each request is small. Identify the blocking calls and the right fix for each.
Implement
classify_async_calls(calls: list[str]) → list[str]Examples
in
[["file.file.read","hashlib.sha256","time.sleep","open","f.write"]]out["use_await","use_threadpool","use_await","use_threadpool","use_threadpool"]in
[["await file.read","await asyncio.sleep","return digest"]]out["ok","ok","ok"]in
[[]]out[]What a strong answer looks like
Treat the AI’s output as a draft to verify, not an answer to trust. Name the specific flaw and the input that triggers it, say how you’d catch it (tests, edge cases, reading critically), and how you’d re-prompt or decompose to get it right.
0:00 of about 19 min
Vibe & agentic: describe the solution in plain language (or narrate it) and the coach grades your approach.
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.
Run or narrate your approach, then ask the coach.