Manage fulfillments as a fulfillment service app

This guide describes how fulfillment service apps can use the Admin API to manage fulfillments in Shopify. If your app manages a FulfillmentService location (such as a third-party warehouse that prepares and ships orders on behalf of the store owner), then follow this guide. If your app doesn't manage a FulfillmentService location, but it assigns orders to be fulfilled by the merchant or by third-party locations, then you can follow our guide on managing fulfillments as an order management app.