Offline ZATCA-Compliant POS Software

I need a desktop Point of Sale application that can run fully offline on Windows yet still remain 100 % compliant with ZATCA’s e-invoicing and Saudi VAT regulations. The system must feel natural on a touch-screen terminal, so button sizes, on-screen keyboards and quick-tap workflows are essential.

Core modules I must see from day one are:
• Inventory management with real-time stock deduction and simple purchase-order entry
• Sales reporting that can filter by date, product or cashier and export to PDF or Excel
• Customer management for saving basic client details, loyalty points and quick look-ups

Even though the system operates offline, it should be ready for future online syncing or XML/QR code generation as required by ZATCA standards. I’m flexible on the tech stack, provided you deliver a stable Windows installer, clear setup instructions and a brief user guide.

I’ll consider the job complete when:
1. I can install the app on a fresh Windows machine with key generation portal licensing.
2. I can ring up a sale on a touch screen, print a ZATCA-compliant invoice with QR code, and see the transaction reflected in inventory and reports.
3. Source files or build instructions are supplied so updates are possible later.

If you have previous POS or tax-compliance experience, please tell me—otherwise just show me a quick demo build or screenshots so we can move forward quickly.