ks · solutions / duedale
Duedale
Duedale is the wallet-marketplace startup. Whiffin is its payment infrastructure — a blockchain gateway that behaves like a POS terminal at the counter and a developer API at the integrator.
the product · Duedale ships
Whiffin.
Blockchain payment gateway + POS terminal. Tap to settle; receipts both sides sign.
Whiffin is Duedale's payment stack. Two surfaces, one settlement layer: a POS terminal the buyer taps at the counter (with Passkey biometric to authorise), and a developer gateway the merchant integrates with their own checkout. Both routes settle on chain; both produce DID-signed receipts that the buyer and the seller take with them.
Behind the familiar terminal UX is the full Trade-SDK paradigm range — OTDC for one-time purchases, Subscription for recurring, Escrow for delayed delivery, Auction for price discovery, Milestone for project work. The merchant picks the paradigm; Whiffin handles the flow.
the parent · Duedale
Duedale is a wallet-marketplace startup. Buy, sell, swap — every transaction backed by a DID-anchored wallet, signed by Passkey, and final-on-chain in seconds. No platform-of-record holding the keys, no rating system the platform can edit out from under you.
Whiffin is the payments product Duedale operates. Merchants accept payment through it; integrators reach the same flows through the gateway API; everyone walks away with a signed receipt that's verifiable without trusting Duedale.
What's inside.
POS terminal
Buyer-side UX that behaves like Stripe Terminal: tap, biometric, done. Settlement is on chain; the receipt is signed by both parties.
Gateway API
Integrator-side surface for developers building their own checkout. EIP-712 signal contracts, REST + WebSocket fallbacks for state subscription.
Five paradigms
OTDC, Subscription, Escrow, Auction, Milestone — one deployed factory, five flows. Whiffin picks the right one per transaction.
Portable reputation
Your buy/sell history is signed by both sides. Take it to another marketplace; nobody can rewrite it once it's chained.