In a Dutch auction, an item is initially offered at a price exceeding the amount the buyer expects to pay. Then the price is gradually lowered until a bidder accepts the current price.
In this example, we use the same tools as in the previous one, also adding a delta for a step price. The account’s script checks if a participant has actually placed the first bid for the current price.
A public key and the sender’s signature will have to be added to the transaction proofs. Otherwise, the blockchain doesn’t accept the DataTransaction.