Cancellation

The problem

A retry loop can run for a while — backing off, waiting, trying again. If the work becomes irrelevant (the user navigates away, a parent request is cancelled), you need to stop it cleanly, including any pending wait.

The solution

Pass an AbortSignal. If it's already aborted, fn is never called. If it aborts during a wait, the pending timer is cleared and the promise rejects with the abort reason. Where AbortController is available, the signal is also handed to fn (and to attemptTimeout's per-attempt signal) so in-flight work can cancel.

const controller = new AbortController();

const promise = retry((attempt, signal) => fetch('/api/slow', { signal }), {
  times: 5,
  signal: controller.signal,
});

// Later — e.g. the user navigates away:
controller.abort();

The promise rejects with the signal's reason, so you can tell cancellation apart from a genuine failure.

Try it

Press Run, then Abort mid-flight — the sequence stops and the pending wait is cleared.

attempt timelineidle

• failed
• timed out
• bailed
• pending
• succeeded

Hit Abort during a wait to cancel the loop straight away.

timesretries after the first failurefailUntilattempts that fail before successinitialDelayTimems before the first retry

1. Press Run to start.