A quieter API for long jobs

Start the job, then leave

Long jobs used to hold a connection open and hope nothing in the middle dropped. That was a poor fit for exports, evals, and anything that runs past a minute.

The quieter API takes the request, returns an id, and lets you ask for the result when you want it. Progress is a single field, not a stream you have to babysit.

Webhooks are optional. If you would rather poll, polling works, and it does not count as a new job.