Offline-first till
The catalogue lives on the machine, so a scan is instant with no connection. Every sale is written locally before anything can fail, then synced when the line returns.
Product — built, not yet in a live shop
Prospra IQ. A till that keeps trading when the line drops.
Till and stock control for South African shops. It keeps selling when the internet goes down, and books every cent correctly the moment it comes back.
The problem
Retail software assumes a connection that South African shops do not have.
Load-shedding takes the router. The fibre goes down for an afternoon. The line at a rural counter was never reliable to begin with. Most tills stop selling, and the shop reaches for a receipt book.
What comes back from that receipt book is a day of stock movements nobody recorded, VAT figures reconstructed from memory, and a gap in the invoice sequence that SARS will ask about.
Prospra IQ is built the other way round. The connection is treated as optional, not assumed — and the arithmetic as the thing that must never be wrong.
Built for
- Grocers, general dealers and forecourt shops
- Hardware, agri and building supply counters
- Pharmacies and anywhere batch and expiry matter
- Multi-branch operators needing stock per location
The till
Fast enough for a queue.
Scan, tender, print, next customer. The screen a cashier actually looks at for eight hours — not a dashboard.
Prospra IQ · Till 2 · Working offline — 3 sales queued
Sale in progress
Cashier: T. Mahlangu · Branch: Main
| Item | Qty | Price | Line |
|---|---|---|---|
| Maize meal 12.5kg | 2 | R 189.99 | R 379.98 |
| Cooking oil 2L | 1 | R 79.95 | R 79.95 |
| Beef mince (0.842 kg) | 0.842 | R 129.00/kg | R 108.62 |
| Bread, white | 3 | R 21.50 | R 64.50 |
- Subtotal excl.
- R 550.48
- VAT at 15%
- R 82.57
- Total
- R 633.05
- Change
- R 66.95
Design preview of work in progress. Prospra IQ has not been commercially released and this is not a screenshot of a live installation.
What is in it
Twelve parts, one record.
A sale at the counter moves stock, posts to the ledger, allocates a tax invoice number and lands in the day’s Z-report — in one transaction that either completes entirely or not at all.
Never charges twice
If the line drops mid-sale and the till sends it again, the system knows it is the same sale. One sale, one invoice number, one movement of stock.
Barcode scanning
Hardware scanners act as fast keyboards; the till tells a scan from typing by the gap between keystrokes. Fractional quantities for weighed goods.
Payments
Cash, card, EFT, account, voucher and split. Change calculated automatically, and a cash sale tendered below the total is refused rather than rounded.
Receipts & hardware
Works with the till-slip printers on South African counters, including the older ones a lot of shops still run, and pops the cash drawer open when the sale goes through.
Products & variants
One product, many sellable variants, each with its own SKU, barcode and price. Stock is held per branch rather than per business.
Batch & expiry
Tracks batches and expiry dates, and sells the oldest stock first. Anything within 30 days of going out of date gets flagged while you can still move it.
Goods received
Book in a delivery and the system keeps your real cost per item up to date as supplier prices move. It also remembers what each item cost you on the day it sold, so your profit figures are real rather than guessed.
Inter-branch transfers
Dispatch and receive as separate steps, so stock in transit is visible instead of vanishing between two locations.
Customers & credit
Credit limits enforced at the point of sale. An account sale that would breach the limit rolls back entirely rather than slipping through.
Debtors ledger
Every invoice, payment and credit note shows the running balance. Nothing can be quietly changed or deleted afterwards, by anyone.
Z-reports
The cashier declares the counted cash before seeing what was expected. Variance is generated, not typed, and closing the day locks it against voids.
How it is kept safe
A till on a counter is not a trusted machine.
It sits in a shop, runs on hardware you do not control, and is operated by whoever is on shift. The security model starts from that assumption rather than hoping otherwise.
So the till is never trusted with the money. It reports what was sold and how many, and the system itself works out the price, the VAT and the invoice number. Once a sale is recorded, nobody can go back and change it.
- Who someone is comes from the system, not from the till. A cashier who tampers with the app to claim they are the owner is still a cashier.
- A sale either completes or it does not. You will never find an invoice with no items on it, or stock that moved for a sale that was never finished. Mistakes are fixed with a void or a refund that leaves a trace, not by editing the past.
- The cents are always right. The till and the system work the total out separately and compare the two on every single sale. If they disagree, the sale does not save.
- 212 automatic checks run over the system every time anything changes, and 11 of them will stop a release outright if a security rule has slipped.
- Invoice numbers that never skip. A number is only used when a sale actually completes, so an abandoned basket does not leave a hole for SARS to ask about.
- Your VAT return figures, worked out and then checked a second time against the actual sales behind them.
- Financial and year-end exports in CSV and PDF, formatted for Sage, Pastel, Xero and Excel — your accountant imports rather than re-keys.
- Five-year retention of tax records, with a POPIA erasure register on the statutory 30-day clock.
- Customer details never end up in system logs or web addresses, where they would be easy to leak by accident.
Compliance
The parts SARS and the Regulator actually ask about.
Not a compliance module bolted on at the end. Invoice numbering, how long records are kept and how they get erased are built into the way the data is stored. That is the only place they can be enforced rather than just promised.
Erasure pseudonymises rather than deletes, because five-year retention and the right to erasure genuinely conflict. That is the standard resolution, and it is worth a lawyer’s confirmation before you rely on it.
Questions
What merchants ask us.
Including the answers that cost us the sale. A till is not something you find out the truth about in month three.
Can I run my shop on it today?
Not yet. The system underneath is built and tested, and both the office side and the till run. We are now looking for a first shop to run it alongside their existing till while we finish the last stretch together.
What happens when the internet goes down?
The till keeps selling. Your prices and barcodes sit on the machine itself, so scanning is instant with no connection at all, and every sale is saved on the till before anything else can go wrong. When the line comes back the sales upload themselves, oldest first. If one gets sent twice it is recognised, not duplicated.
Can a cashier change a price or edit a past sale?
No, and not by fiddling with the app either. The till never decides prices, VAT, totals or invoice numbers. It reports what was sold and how many, and the system works the rest out from your own price list.
Voids and refunds are manager-and-above, need a written reason, and write an audit record that cannot be edited or deleted.
Will it work with my existing receipt printer?
It is written for the till-slip printers used on South African counters, including the older ones plugged in the old way. Printer support is finalised on real hardware with the first pilot shop, which is one of the reasons we want a shop with a real counter rather than a lab.
Will my invoices and VAT figures satisfy SARS?
Yes. Invoice numbers run in order and never skip, and a number is only used once a sale actually completes. The VAT report gives you the figures your return asks for.
Partial refunds work, priced at what the customer originally paid. They are not yet SARS credit notes, and we will not call them that until an accountant has signed off the serial-number requirements.
Does it work with my accounting package?
Exports work. Financial and year-end reports come out as CSV and PDF, formatted for Sage, Pastel, Xero and Excel, so your accountant imports the file instead of re-keying a year of takings.
The automatic link-up is built and goes live with the first pilot. The connections to the main accounting packages and online stores exist. Tell us which one you use and it goes to the front of the queue.
What will it cost?
Not finalised. There will be three tiers — Starter, Professional and Enterprise — separated by branches, users and the depth of the stock and ledger features. Early access merchants get preferential terms in exchange for real feedback from a real counter, which is worth more to us right now than the subscription.
Where it stands. The system underneath is built and has been attacked deliberately to find its weak points. Both the office side and the till run. The last stretch is the part that only a real counter can finish: printers, the accounting link-up, and a full trading day end to end.
Before any shop runs its trading on this, we finish the things that protect you if something goes wrong: proper backups that we have actually restored from and timed, keys kept in a vault, and a signed installer so Windows does not warn you when you install it. We will tell you when those are done, and not before.
Pilot merchant
We are looking for one shop to go first.
Run it beside your existing till, not instead of it. You get preferential terms for as long as you use it; we get the thing no amount of testing produces — a real counter, a real queue and a real month-end.