Discover Singular's innovative oracle, enabling off-chain listing cancelations and price changes without the need for a blockchain transaction. This means zero gas fees for users!

Off-chain cancelations as available for all listings created on or after March 31, 2023.

Off-chain listings have become common in the NFT space, as storing all listings on-chain would be expensive. For a listing to be valid and purchasable on the blockchain, users must sign the listing using their private keys.

Traditionally, a blockchain transaction has been required to cancel or increase the listing price, which would invalidate the listing. This process involves appending the listing's unique identifier (known as the order hash) to the list of canceled orders in the blockchain protocol, preventing future purchases.

Singular listings require signatures from both the NFT owner and Singular's custom oracle for a listing to be valid and purchasable on the blockchain. The owner signs the order when creating the listing, while the oracle co-signs the order when a buyer wants to complete the purchase.

The key feature is that the oracle's signature remains valid for only 90 seconds.

To cancel a listing, users simply inform the oracle not to co-sign any longer, which effectively removes the data from the database.

From a buyer's perspective, this means that transaction data retrieved from Singular's server (awaiting signature in Metamask) is only valid for 90 seconds. If Metamask remains open for longer than 90 seconds before signing the transaction, the transaction will fail.

This limitation is not seen as a drawback, but rather a beneficial feature. Current web3 UX often leads to mistakes, such as signing an old transaction that remained in Metamask or purchasing an asset with low gas presets. In most cases, users would not want a transaction to succeed after more than 90 seconds anyway.

Singular listings created on or after March 31, 2023, can now be canceled off-chain without incurring gas fees.

To cancel a listing, navigate to the Owned tab in any collection and click the cancel button next to any Singular listing you have created. The listing will be immediately removed from the market.

If a buyer attempts to complete a purchase just before the cancelation, they may have up to 90 seconds to process the transaction. A time indicator will be displayed, alerting you that someone might still buy your asset within the following seconds.

Read the documentation of the SIP-7 open standard here: https://github.com/ProjectOpenSea/SIPs/blob/main/SIPS/sip-7.md