Inventory and locations
Stock is counted per variant, per location: a warehouse, a shop, a supplier who ships for you.
Locations
Section titled “Locations”Every store has a location from its first start, named “Default”. Add more as you need them, and say which markets each serves, so a cart is only promised stock that can reach it.
Inventory items
Section titled “Inventory items”A variant whose stock you track has an inventory item, with a level per location: how many are on hand. A variant without one is never out of stock (made to order, digital, a service).
When a shopper checks out, the order reserves the stock it takes, in the same write that creates the order, so two shoppers can’t buy the last unit twice. Fulfilling the order takes the units out of the location they ship from; cancelling gives them back.
Stock changes are events like any other: apps and the storefront’s cached pages follow them through webhooks.