Authentication is not implemented in the backend of API like not done JWT passport properly.
Simply Good and Product also.
So much good code and design for the price - first class A+
It is very well built. It was my first time dealing with Next.js, as I have been working with React only the past couple of years.
Really the heavy lifting of the e-commerce workflow is mostly done (Cart, Store, Search, Filters...) all you need is just to put your business logic and you are good to go. :)