Encrypted ERC721 and market place

[Lcressot]

Zama Bounty Program: Proposition

fhEVM

• Overview: I propose to create an encrypted version of ERC721 smart contract, where the wallet owner of NFTs is encrypted, along with a demo market place smart contract and UI.

• Description: Encrypted ERC721: as users need to be able to know what tokens they own, and this info is encrypted, a quick way to decrypt the information is required. I suggest a compromise to make this possible where each wallet can own a maximum of 16 tokens on the contract, and the contract can mint a maximum of 65k+ (2^16) tokens. This will require the euint256 type to be available on fhEVM. For now, we could make a demo with maximum 4 tokens per wallet and 256 tokens per contract using the existing euint32 type.

Marketplace contract: it will allow any kind of erc20 tokens for paiement, even encrypted erc20.

Marketplace UI: it will allow a user to decrypt which tokens it owns for a given ERC721 collection. The user will see what NFTs are on sale, and will be able to create bids for purchasing or selling. As subgraphs are not available yet for ZAMA blockchain, the fetching of past events will be limited to few thousands blocks into the past. A subgraph for the marketplace will be handed for when it becomes possible to use it.

• Reward: 15k $

• Related links and reference:

[zama-bot]

Hello Lcressot,

Thank you for your bounty proposition! Our team will review and add comments in your issue! In the meantime:

1. Join the FHE.org discord server for any questions (you’ll find a dedicated #zama-bounty-program channel).
2. Ask questions privately: bounty@zama.ai.

Talk soon,

[Lcressot]

Sorry I figured this cannot be done. Keeping an address encrypted will never work because when a txn is done, we know what address made it, and we can link this to the info that should be hidden.