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In this example, mod-inventory-storage is the set of storage APIs for inventory, and mod-inventory is a business-logic set of APIs that the Inventory module uses.It's important to understand that the distinction here
Are there always storage modules and business logic modules for each app?
No. Much of the structure of these modules is a matter of project historical design choices and practices, and so it is really important to know that you can't always be certain that a particular app has modules that work this wayworks this way. But many of the most frequently-used apps and "heaviest-used" apps, like Inventory, have this structure.
Some general statements about storage modules:
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