ZKard
ZKard offers a trustless integration for banking institutions and card providers to connect with users' Smart accounts. This allows users to leverage their existing DeFi assets to collateralize loans on a credit card.
Screenshots
Problem Statement
ZKard allows users to leverage their existing DeFi assets to collateralize loans on a credit card.Key features include:Utilizing zero-knowledge proofs to ensure integrity and create a trustless payment settlement environment.Employing Gnosis Safe SmartAccount (Account Abstraction) for secure, permissioned access to users' DeFi positions.
Solution
Fiat credit limits against crypto collateral are possible because of:Gnosis Safe EIP-7579 to share a wallet between the client and the bank, allowing the bank to liquidate the client under certain conditions, and the client to withdraw funds at any time under certain conditions.ZK proofs using Zokrates - every time the client makes a payment, the client generates a signature, which is later pushed to a zero-knowledge log. The bank settles the payment right after the log is added. This approach keeps the client’s payment history secure while enabling the bank to liquidate the client’s collateral if certain limits are reached. A smart contract and price oracles can prove this. Similarly, the client can withdraw funds if the limit is repaid.Circle USDC and ETH are used as crypto collateral; however, any DeFi position can also be used as collateral.