Visa proposed a blockchain account design that would allow Ethereum users to arrange automatic payments from their self-custody wallets.
The payments giant described its approach as blog post The post summarizes a previous research paper published in August.
Visa proposes to implement automatic payments using Account Abstraction, a feature of Ethereum currently being considered by core developers.
According to the company, this will allow users to set up recurring bill payments. Ethereum disallows this at a fundamental level, as automated smart contracts cannot request transactions. Rather, the user her account must manually initiate and submit transactions.
Visa said it can easily arrange automatic payments using bank accounts and custodial crypto wallets, but this type of payment is “not easy to do on blockchain.” It is difficult to implement in a custody wallet—a wallet where users have full control over their funds.
The company said it explored possible solutions as part of this year’s internal crypto hackathon challenge.
Visa explained that by using the account abstraction, it was able to combine the functionality of user accounts and smart contracts into one type of Ethereum account. The company called the resulting account a “delegable account.”
This approach allows merchants to deploy auto-payment smart contracts. After granting permission by a user with a delegable account, merchants can call the autopay contract’s billing function to trigger payments. The user’s delegable account whitelists the autopay agreement for future payments.
Visa says Ethereum itself has not yet implemented an account abstraction, which exists as part of various proposals such as EIP-4337. In light of these limitations, Visa has implemented delegable accounts on StarkNet, Ethereum’s Layer 2 network that extends the functionality of the underlying blockchain to support functionality.
Visa appears to have created an automated payment solution that works, but did not show that it would offer that functionality to its customers.
It seems unlikely that this feature will be implemented on Visa’s wide range of cryptocurrency payment cards. These cards are often linked to custodial exchanges. However, this feature may be used by Visa payment services for merchants and banks, and may need to interact with non-custodial Ethereum wallets.