DUSD at the Till: Square Sellers, a Paymaster and No Card

The observation the old title made

Cards brought stablecoins to shops elsewhere by hiding the chain behind a network merchants already accept. It is a real strategy, and it needs a card issuer, a network agreement and a licence — none of which this ecosystem has or is pursuing.

The route here

Square Sellers (com.gnoosis.empooriosquaresellers, production 1.0.3) is the app a shop or stall already uses. The designed DUSD payment:

Seller taps Charge 4.50 DUSD. The app renders a QR encoding eoonia://pay?to=…&asset=DUSD&amount=4.50.
Customer scans with Eoonia; sees the request decoded; approves.
Eoonia submits a stablecoins.transfer (or escrow.lock if the seller wants delivery-conditioned release). Fee ~0.000025 DMS — paid by the seller's paymaster, so the customer holds only DUSD.
Included in ~3.5 s; the seller's app shows received. Finalized in ~17 s; done.

No card, no network, no issuer. The stable unit moves from wallet to wallet on the chain both already use.

What makes it viable for a stall

Fee sponsorship: a DMS in the paymaster covers thousands of sales.
A stable unit: DUSD targets $1 (target, not guarantee).
No hardware: a QR on the seller's phone.
Verified-human discount: the seller's KryptoOS credential earns up to 50 % off fees.

What is missing

eoonia://pay sent from Square Sellers: the deep-link plumbing is live (Warehouse uses it for linking and minting); the payment request from a commerce app is not wired.
A merchant holding a paymaster: none.
DUSD in customers' wallets: DUSD is a testnet asset; nobody holds it for value.
Off-ramp: the seller ends with DUSD, not euros. The apps settle in fiat today for exactly this reason.

The first till payment

Will be a test stall, a test customer, 4.50 test DUSD, four sponsored transactions, on the public testnet, with block numbers. This page will carry them. The Trojan horse here is not a card; it is an app that already exists in a shop, waiting for one more button.

Based on the Play Developer API (2026-09-08), PALLET_REFERENCE.md, TOKENOMICS.json (gas_en_dusd) and the Eoonia deep-link scheme.