Running a promotion or sale event

Promotions and sale events introduce discount logic, volume spikes, and sometimes unusual order structures that can surface edge cases in your integration. This checklist helps you prepare and respond.

Before the promotion

Confirm discount handling If you're using a new discount type (e.g. a new discount code structure, bundle pricing, or gift-with-purchase), test it in advance. Place a test order and verify it flows correctly through to your ERP or destination system. If anything looks wrong, raise it with HC before the sale goes live.

Confirm volume readiness If you expect significantly higher order volumes than normal, let HC know. HC can confirm whether any rate limits or queue configurations need adjusting ahead of time.

Confirm alert configuration Check Settings > Notifications to make sure alerts are going to the right people and the thresholds are appropriate for elevated volume. A failure rate that would be unusual on a quiet day may be normal during a flash sale — and vice versa.

During the promotion

Monitor the Control Panel actively, not just passively. Specifically watch:

• Failed events — any sudden increase in failures warrants immediate investigation

• Retrying events — a growing retry queue can indicate an upstream or downstream API issue

• Unusually low volume — if orders are coming in on Shopify but not appearing in HC, something may be blocking events from reaching the integration

If you see anything unexpected, contact HC straight away. Don't wait to see if it resolves itself.

After the promotion

• Review the event log for any failures that occurred during the window

• Check that failed events have been reprocessed or deliberately excluded

• Verify inventory levels in your destination system — sale events can create rapid stock movements that occasionally trigger edge cases

• Check financial postings for the period to confirm discount values and order totals have posted correctly

If you find failures that weren't caught during the promotion, raise them with HC with the relevant order or event references.