It might be very useful for monitoring, I agree. Be careful that all of this is extra state to maintain, though. For example, who is responsible for unregistering the jobs from the registry again? There are three scenarios, I think:

- The job executed successfully
- The job failed
- The job was cancelled

If I kill a worker with `SIGKILL`, what happens to this registry? Job's won't have a chance to be unregistered that way. Can/will garbage be detected and cleaned up automatically again?