Great question — answering as the UphillTech team:
My recommendations so you can assess and take your own decisions. I don't know all the details and some of them could be related to the organisation structure itself. You are suspicious about Crossing boundaries and you are right to do so. Crossing boundaries have its penalties in terms of development costs, complexity, so you should try to minimise it if possible. Don't try to create the perfect theoretical solution in your head. It is better to start simple even at the cost of purity, and go to detail later when the experience and knowledge indicates you. I agree with the interactions between the Product Catalog, Pricing and Shopping cart. I would start increasing the Shopping cart...
Full answer by Jose Marin: https://stackoverflow.stackexchange.com/a/77677972 (CC BY-SA 4.0).
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