WonderSync

Cross-list your Shopify inventory to eBay DE and eBay US. When something sells anywhere, it's taken down everywhere else within seconds — built for quantity-1 resellers where overselling is not an option.

• Webhook + polling + reconcile sweep — three overlapping layers of sale detection
• Atomic first-event-wins claim — exactly one winner, never a double-shipped order
• Failed delists escalate loudly instead of failing silently