Replay safety checklist

Canonical guide: https://sendpromptly.com/docs/guides/webhook-delivery-log-replay/

Before you replay

  • Confirm your handler is idempotent (unique key / inbox row)
  • Confirm the bugfix is deployed
  • Confirm the replay window (what range of deliveries)
  • Confirm side effects are safe (no double-charge, no double-email)

During replay

  • Start small (1–10) then scale
  • Monitor error rate and queue depth
  • Stop if you see duplicates

After replay

  • Audit: count of replays vs completions
  • Preserve correlation IDs in logs