A user clicks "Publish". That has to write the post, reindex it for search, generate three thumbnail sizes, and email 4,000 subscribers. What runs in the request and what does not?
Answer it out loud before you open anything. The value of the flags below is in comparing them to what you actually said.
The situation behind the question
A publishing product. Today all four steps run inline in the POST handler; it usually finishes, and sometimes the browser times out and the author clicks Publish again.
What it is really testing
Whether the candidate has a criterion for deferring work rather than a habit. The interesting part is not "emails are slow" — it is that deferring changes the contract: the response now means "accepted", not "done", and the client and the product both have to be told.