Loading
Offline Windows business system for a tile and sanitary ware shop
The whole counter of Umar Tiles & Sanitary Store, Mingora — selling, buying, stock, khata, returns, expenses, profit and printed invoices — as one Windows program that never opens a network connection. Every record lives in a single SQLite file on the shop computer.
A tile shop in Swat cannot lose a day’s trade to a dropped line, and will not pay a monthly fee for software it already owns. So the requirement was inverted: not “works offline”, but has no online at all.
Tiles are not sold in units. The same shelf holds a carton of four and a carton of eight, and a customer buys three cartons plus two pieces. Stock kept as a carton count silently corrupts itself the first time two products disagree — and money kept as a decimal loses rupees to rounding across a year of invoices.
Stock is stored in base pieces and cartons are derived from each item’s own pieces-per-carton, so two products can never contaminate each other. Money is stored as whole paisa, never as a float. Profit uses the weighted average cost captured at the moment of the sale and written onto the invoice line, so buying more stock later at a new price cannot rewrite an old invoice. Every sale is one database transaction: the invoice, its lines, the stock movement, the khata entries, the payment and the profit figures all commit, or none of them do.
Version 1.4.0, in use at the shop in Mingora. Installed from a Windows installer handed over directly, not through an app store, so there is nothing to open.
Concept
Architecture
UI / UX
Development
Database
Testing