Dutch Auction for Paymenter

A Dutch auction: descending-price plus buy-now, with no bidding. Each item starts at a high price and ticks down on a schedule toward a floor price; the first buyer to accept the current price gets it.

All of them. Clients buy through Paymenter's normal order → invoice → gateway flow, and the invoice line is rewritten to the current auction price server-side — so the gateway only ever sees a standard invoice and any gateway extension works unchanged.

No. The price is authoritative on the server — the client never submits a price. A single deterministic pricing engine computes it from elapsed time for the listing, countdown, feed and the actual charge, so even a missed or doubled cron run can't skew what a buyer pays.

Each item tracks stock (multi-unit, or blank for unlimited) with an oversell-safe reservation: units are reserved when an order is placed, released if it's cancelled, and confirmed sold only once the invoice is paid.

Yes. A public, read-only feed with open CORS provides JSON, an HTML fragment, or a one-line embed script, so any external site can display your live auctions. It exposes only public listing data (name, prices, units left, expiry, buy URL) — never client, billing or account data.

Auctions live on a dedicated Auction checkout page, and the same products keep their normal price on every other page — the auction price applies only on the Auction page. The page is created and kept in sync automatically, and the extension self-heals its checkout integration after a Paymenter update within one cron run.

Under Tools → Dutch Auction → Create Auction, set the name, currency, number of price reductions, rounding, start and end times, and whether to restart on expiry. Then Manage Items → Add Item (or Bulk Add) to pick the product and pricing term and set the starting price, floor price and stock. On expiry an auction either restarts with fresh stock or ends.