Visa Card payments for gas fees
A user initiates an Ethereum transaction through their wallet, which then sends the transaction details to the paymaster web service.
The web service calculates the cost of the gas fee and subsequently charges the user’s Visa card using Visa’s Cybersource system to process the card payment.
Following this, the web service sends back a digital signature to the wallet, approving the payment. This approval is valid for a specified time window.
The wallet attaches this signature to the transaction and forwards it to Ethereum.
The paymaster smart contract then verifies the validity of the signature and covers the gas cost to process the transaction.