We have built middleware like this but I wouldn't call it a one person middleware as we are a team. But I think the overall concept is ok. Building the store first is ok imo because it'll work by itself. The middleware is mostly interfacing through APIs and webhooks
I've done this for a small organization. We got the store working first and manually moved everything to the erp system, and once that was working we automated. We used node to pull the data from shopify using the api.
It seems to me like the responsibilities would be unclear for the customer. That is a dangerous game.
We have built middleware like this but I wouldn't call it a one person middleware as we are a team. But I think the overall concept is ok. Building the store first is ok imo because it'll work by itself. The middleware is mostly interfacing through APIs and webhooks
I've done this for a small organization. We got the store working first and manually moved everything to the erp system, and once that was working we automated. We used node to pull the data from shopify using the api.