How does checkout work in the orders service? Driver get_atlas_index, orders / master. Four components: Runtime configuration — service addresses and monitoring. Health reporting — application and MongoDB status. Order creation — payment, shipment and saved order. Test harness — unit, component and integration tests. Order creation is highlighted. I’ll open Order creation. Driver get_atlas_detail, orders / master, Order creation and checkout models. Checkout follows this sequence: 1. Validate request. 2. Authorize payment. 3. Request shipment. 4. Save order. Source: OrdersController.java, newOrder. Component labels and the checkout sequence are condensed from captured live Atlas index and detail responses. The index covers 27 of 35 mapped-eligible files; no inter-component dependency edges are implied.