Design an Inventory Management System

Design an inventory management system. Explain the scope you choose, the records it stores, the operations that change stock, and how users obtain a current inventory view. The product domain and detailed workflow are unspecified. Establish a coherent minimal model before choosing infrastructure, and distinguish your assumptions from required behavior. Explain how the system prevents conflicting updates from silently corrupting stock and how an operator can investigate a discrepancy. ### What a Strong Answer Covers - Clear identities for items and any stock locations, with an explicit meaning for the quantity being tracked. - Stock-changing operations and validation rules that fit the chosen workflow. - A consistent update path, retry behavior, and an audit trail connecting a balance to its changes. - Read access patterns and the consistency tradeoffs of secondary views or caching. - A practical way to reconcile physical observations with recorded stock rather than overwrite history without explanation. ```hint Define the balance A quantity may mean physical units, available units, or units committed to a future operation. Choose one meaning and make every update preserve it. ``` ### Follow-up Questions - What happens if a stock-changing request succeeds but its response is lost? - How would the design distinguish a duplicate request from a legitimate second operation with the same quantity?