Every bike shop we looked at was running its service department on something Shopify couldn't see.
A whiteboard by the workstand. A clipboard of parts to order. A spreadsheet of who to call back. Or a separate repair app with its own product catalog and its own customer list, which meant someone spent the last twenty minutes of every day making two systems agree.
None of that is a software problem in the abstract. It's a specific one: the service department produces work that has to end in a sale, and if the tool that tracks the work isn't the tool that takes the money, a person has to bridge the gap by hand, every single time.
So ShopTech was built on top of Shopify rather than alongside it. It's a separate app: the work orders, the parts ordering, the stock counts, and the customer's repair tracker all live in ShopTech, because Shopify has no place to put them. What it never does is keep its own copy of the commerce data. Parts are Shopify products. Customers are Shopify customers. A finished repair becomes a Shopify sale. The bridge is gone because there's nothing left to bridge.
We started with bike shops because their service work is the most demanding version of the problem: long jobs, special-order parts, customers who want to know what's happening, and a bench that's already full. What works there works in most service retail.