I created user, tax, product, cart and customer classes with repositories and services. I choose MySQL for database and I built whole system on it.
In UI I used JFrame, JPanel and etc. (Java Swing and Awt).
You can add tax and product and customer for creating carts and basic tracking like is that paid? what products are ordered and what's currently stock? Also you can create different users to manage. There's no roles for now but it can be added cause I built flexible system to develop new features easily.
