Backfill Launcher
Manually re-run a cron job over a historical time window.
Last updated 05/24/26
What this surface does
The Backfill Launcher is a controlled way to re-run a cron job over a chosen historical window. Logs each backfill to `backfill_runs` (migration 197) with operator, parameters, and outcome.
When to use it
- A cron job failed silently for a few hours — backfill the missed window.
- A new categorisation rule needs to apply to historical bank transactions.
- Recomputing an analytics rollup after a data correction.
Key gotchas
- Backfills are not idempotent by default — re-running the same window can double-write unless the underlying job has dedup logic. Check the job's notes before launching.
- A backfill that touches GL must be reviewed — accidental duplicate journal entries are painful to clean up.
- Long backfills hold DB connections. Run during off-hours for anything covering >7 days.
Related
- Cron Health, General Ledger.