How our contract works

A sale, step by step

1. 1
   ListYou sign

   Your NFT goes into the contract. Written with it: your price, your address, the creator royalty, and who gets each fee part.

2. 2
   BuyBuyer signs

   A buyer signs one transaction that pays the price. Nothing else is needed from you.

3. 3
   Everyone is paid at once

   The contract checks every payment in the transaction before the NFT moves. If one is missing or too small, the contract rejects the whole transaction: nobody is paid and the NFT stays listed.

   • NFT to the buyer
   • Seller97.5% minus royalty
   • Creator's accountroyalty
   • JamOnBreadfee parts
   • Referrers' accountsfee parts
4. 4
   ClaimOwner signs

   Creators and referrers withdraw from their accounts whenever they want. Only their own wallet can sign for it.

How the fee is split between JamOnBread and referrers: Fees.

What the contract checks on every sale

• The seller gets the price, minus the 2.5% fee and the creator royalty. Nothing else can be taken.
• Each fee part goes to the account written in the listing, and the royalty goes to the creator's account.
• Only the seller can cancel the listing or change its price.
• The price is above the contract minimum of ₳1.

Audits

Our contract has been audited twice, by Vacuum Labs (internal audit) and by Sundae Labs (external audit).

Offers

An offer works the other way round. The buyer locks ADA in our offer contract together with what they want: one specific item, or any item from a collection. A holder accepts by sending the NFT, and the same fee split comes out of the offer.

1. 1
   Make an offerBuyer signs

   Your ADA is locked with the item or collection you want. You can cancel and take it back any time before it is accepted.

2. 2
   AcceptHolder signs

   A holder sends a matching NFT. For a collection offer, any item from that collection counts.

3. 3
   Settled

   NFT to the buyer. ADA to the holder, minus the fee and royalty. Same rules as a sale.

Accounts instead of direct payments

Fees, royalties and referral earnings are paid into on-chain accounts, not straight to a wallet. Each account can only be withdrawn by the wallet it belongs to.

Cardano requires every output on the chain to hold a minimum amount of ADA, about ₳1. A contract that pays each fee and royalty as its own new output has to round every small amount up to that minimum, and the buyer pays the difference. Our contract adds each part to an account that is already open instead, so small amounts are paid as they are.

Why it matters on cheap items. The 5% royalty on a ₳10 sale is ₳0.50, and the whole 2.5% fee is ₳0.25. Paid as new outputs, each would need about ₳1. Here they are paid as they are, plus a small top-up of a fraction of an ADA.

The minimum that opened an account stays in it, so the account can keep receiving payments. The first payment into a brand new account pays that minimum once.