Mainstack POS — Online and In-Store Payments

What "in sync" actually means

Mainstack POS runs your physical stores on the same platform as your online store — one product catalogue, one inventory pool, one customer database. A sale at the counter and a sale online are the same kind of sale.

It connects directly to Linkly-compatible EFTPOS terminals from the major Australian banks — CBA, Westpac, NAB, St.George, Bank of Melbourne, BankSA, Suncorp and Zeller — so the card payment, the receipt, and your books all happen in one tap. No manual entry. No "process on the terminal, then record it in the system later." No two-o'clock reconciliation.

Bank-direct isn't just cheaper. It's safer.

Mainstack is deployed and customised for your business specifically — not a shared international platform with third-party eyes on every transaction. That matters more than most merchants realise.

When you process through a global payment platform, you're also subject to their dispute rules. Fraudulent chargebacks, "item not received" claims, buyers gaming the refund system — these are platform-level problems that platforms have little incentive to solve in your favour. Your money is held, your account flagged, and you're left arguing with a ticket queue.

Australian banks operate differently. Disputes go through established local banking processes, with protections that actually apply to merchants. You're not a number on an international platform — you're a business banking with an institution that has a direct interest in the local economy, and real accountability when things go wrong.

And because the payment goes bank-direct, you pay bank rates — around 0.5% — instead of the 1.6%+ you'd hand a third-party processor. On serious turnover, that gap is real money.

Case study

How a 30-year Perth retailer finally solved it

"We'd been in business for thirty years. We knew retail. What we didn't know was how badly the technology would let us down."

We're a Perth-based retailer — two separate brands, multiple warehouses, and a history that goes back three decades. About fifteen years ago, like everyone else, we moved online: two ecommerce sites, running alongside the physical stores.

The problem was inventory. We never had a proper POS system — we were entering everything manually into MYOB. Every order. Every stock movement. Every price change across two brands. It worked, in the way that duct tape works. But it was fragile, it was slow, and it was entirely dependent on someone doing the right thing at the right time.

We tried the obvious fix: move everything onto one of the big international platforms. Unified retail and online, all in one place. It looked like the answer. It wasn't.

Our products sit at the higher end of the price range, with margins that don't leave much room. At 1.6% or more per transaction, the fees were painful. And then came the chargebacks — buyers exploiting platform dispute rules, claims we couldn't effectively fight, money held while we waited on a ticket queue. A platform built for global scale doesn't particularly care about a single Perth retailer.

So we started looking for something better. That search took over a year. What we found was essentially two categories of solution — and both had the same fundamental problem.

POS providers offered subscription-based systems that worked well for simple retail. But they couldn't handle our product configurations — variants, bundles, complex pricing logic, none of it. And they came with their own terminals and their own rates. We'd have solved one problem and created another.

Ecommerce providers were mostly overseas development shops. A custom build? The quotes came back at $10,000 USD and up — and even then, what we were quoted didn't actually connect to a bank terminal. It was a POS interface that couldn't talk to a PinPad. Just a screen with no payment behind it.

After fourteen months of searching, we'd basically accepted that what we needed didn't exist.

"We weren't looking for anything exotic. We just wanted one system, our bank's rates, and something that actually worked the way our business works. Nobody seemed to be able to build that — until Mainstack."

Client details available under NDA during your consultation.

Built in Perth. Connected to your bank, not a middleman.

Most POS vendors you'll find are overseas — which means offshore support, no local context, and nobody who actually understands how Australian banks and EFTPOS infrastructure fit together. We're Perth-based, in your timezone, and we built this system ourselves.

Your payments settle through your own bank's terminal, at your bank's rates. No middleman. No markup.