A counter that sells, takes the money, and moves the stock

A kitchen is sent onions, buns and patties. A customer buys a burger. Most tills cannot hold both ideas at once, so the stock is either wrong or kept somewhere else entirely.

Here a made-to-order product is a kit: it holds no stock of its own, and when one sells, what it is made of leaves the shelf. Sell two cheeseburgers and two buns and two patties come off the count. The warehouse never sees a burger and the customer never sees a bun.

A shop that buys things in and sells them unchanged carries on as before, and a bakery that bakes a batch in the morning has a third option again. Which of the three an item is, is a property of the item, so a hotel can sell a sandwich, a bottle of water and a cake on one bill without anybody configuring a mode.

Three roles ship with it (Cashier, Shift supervisor, Store manager), and all three are confined to the shop each person works at.

The split that matters: taking money and changing a sale afterwards are separate permissions. A cashier has the first and not the second, because the person handling cash all day should not also be able to rewrite what happened. Refunds and credit sales are separate again, for the same reason. Voiding a sale, discounting past the shop’s ceiling, or closing somebody else’s drawer each need a manager’s PIN, entered in place, and each writes down who allowed it, who asked, and why.

This is the first phase and it is worth saying plainly what is still to come, rather than letting somebody find out at a counter: refunds, the on-screen UPI QR code, and receipt printing. Cash, card and credit all work today; a customer paying by UPI does it through the ordinary payment link until the QR lands.

Also not yet: choices at the counter (extra cheese, no onion, cut to length), tables and open tabs, a kitchen screen, and selling while the internet is down. Each has a switch on the shop’s settings already, so turning one on later changes a setting rather than a system.