We Built a Version of GoCushy for One Country
GoCushy now has a New Zealand site at gocushy.co.nz — prices in New Zealand dollars, GST handled properly, invoices that say GST rather than VAT, and international selling switched off until you turn it on. Building it turned up things about the product we would not have found any other way, and most of them were not about tax.
Software has an accent
You can usually tell where a product was built without being told. Not from the marketing — from the receipt.
A checkout built in London sends a New Zealander an invoice with a line marked VAT. There is no VAT in New Zealand. The tax is GST, the rate is different, and the document is describing something that did not happen. Nothing breaks. The buyer’s accountant corrects it and moves on, the way they have corrected it every month for years.
That is the accent. It is not a bug anyone files, because everyone has learned to work around it.
What we actually changed
Less than you would think, and it was not the hard part.
The New Zealand site prices in NZD, so the number a buyer reads is the number their bank takes. GST applies at the right rate to domestic sales. The invoice says GST, carries a GST number, and is sequentially numbered. Orders and refunds go across to Xero, which is where nearly every New Zealand small business already keeps its books.
None of that is clever. It is the sort of work that gets skipped because it never blocks a launch — it just quietly costs somebody twenty minutes a month, forever, in a country the roadmap has not reached yet.
The thing we did not expect
Somewhere in the middle of it we stopped writing tax code and started writing an evidence feature, and that turned out to be the interesting part.
If a New Zealand business sells a course to somebody in Sydney, that is an exported service and it is zero-rated. No GST. Straightforward — until two years later, when the treatment is questioned and the seller has to show the buyer really was offshore. A billing address alone is thin, because anyone can type any address.
The corroborating signals exist for about four seconds during checkout, and then they are gone. If the cart did not keep them, they cannot be reconstructed. You cannot go back to an order from 2024 and work out where that buyer actually was.
So the checkout keeps them. In most countries that reads like an analytics detail nobody would advertise. In New Zealand it is the substantiation for a tax position, which is a different kind of thing entirely.
We only found it because we were building for one place rather than for everywhere. Generic software cannot have that feature, because it is not a feature until you name the jurisdiction.
Defaults are somebody else’s decision
The other change is that on a New Zealand account, selling internationally starts switched off.
That looks unhelpful written down. The reasoning is that the moment you sell overseas, your GST treatment changes and you may pick up obligations somewhere else as well. Both are fine. Both are decisions. Neither should happen because a toggle was on when you signed up.
The failure mode here is quiet. Nothing errors, nothing turns red, and you discover it while reconciling a return — by which point the sales are made and the treatment is whatever it was. We would rather make you click something.
What this means if you are not in New Zealand
Directly, nothing. The platform is the same platform — we are not maintaining two products and telling you otherwise. What differs is the defaults, and every one of those defaults is a switch that already existed.
Indirectly, this is the shape of what comes next. Currency, tax, invoice wording, timezone and the local accounting integration are not a New Zealand feature; they are a localisation layer that happens to point at New Zealand first. It points somewhere else next.
And the general lesson is one we keep relearning: building for everybody produces software with a faint accent nobody mentions. Building for somebody produces the features you could not have specified in advance.
Have a look
The New Zealand site is at gocushy.co.nz, with documentation covering GST, tax invoices, exports and Xero, and pricing in New Zealand dollars.
If you are in New Zealand and selling online, the fastest way to judge any of this is to run one of your own products through it and look at the invoice that comes out the other end. That document is the whole argument.