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Engineering·5 min read

Integration notes: exclusivity inside Shopify checkout

Where a regional lock has to sit in the Shopify order lifecycle, and the edge cases that catch merchants out.

A regional lock is only as reliable as its position in the order lifecycle. Too early and you block browsers; too late and you sell the same region twice.

The three points that matter

  • Checkout start: take a short-lived reservation keyed on product and region.
  • Order paid: promote the reservation into a permanent claim.
  • Order refunded or cancelled: release the claim back to the pool.

Edge cases to plan for

Draft orders, POS sales, and subscription renewals all create orders that never pass through the standard storefront checkout. Decide whether each should consume a claim before you launch, not after.

Also plan for address edits after payment: if a buyer moves the shipping address into a different region, the claim needs a review step rather than an automatic swap.