Daily Payment Reconciliation Scheduling Relies on Idempotent Run Keys and Webhook Retries

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A DEV Community write-up argues that scheduler choice should be based on the delivery guarantees it can actually prove, not on the convenience of its interface. For a healthtech payment reconciliation job, the author recommends at-least-once execution paired with an idempotent report key. The webhook is treated only as a trigger, while an immutable run record serves as the authoritative source of truth. The article proposes scheduling a run at 02:00 UTC, with separate boundaries tracked for scheduler delivery, run claiming, report publishing, and consumer acknowledgement. It also explains that an idempotency key such as the business date, rather than an "exactly once" label, lets repeated webhook deliveries map to a single logical run.

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