Event ids on every webhook

October 1, 2026Webhooks

Delivery is at least once, so the same event can reach you more than once. Every delivery now carries an id for the event itself, which makes deduplicating a one-line check.

What changed

event_id names one event: this order reaching this state. Every delivery of it carries the same id, to every endpoint, on every retry and every replay.
occurred_at is when the order changed. sent_at is still when Layout wrote the delivery.
order.failure_code is on order.failed: the same stable code GET /v1/orders/:id returns, or null when Layout recorded none.
GET /v1/events takes after, an event_id you already handled, and returns what came next. It also filters by order_id, user_id, event and since. cursor keeps working.

Why it matters

Keep the last event_id you processed. After an outage, ask the feed for everything after it, and skip any event_id you have already seen.

What to do

Deduplicate on event_id and order events by occurred_at. See Payload and GET /v1/events.

Breaking changes

None. The new fields are additive. Events written before this change carry them too, in the feed, on a retry still queued, and in a replay from the console.

All changes