ERC-20 Paymaster FAQs
What is a paymaster?
A Paymaster is a special smart contract under the ERC-4337 specification that user operations are able to delegate the responsibility of gas fee payments to. This means that ERC-4337 smart contract wallets no longer need to necessarily be responsible for directly paying gas fees in ETH. The paymaster contracts are able to use custom logic (with certain limitations) to decide whether or not they are willing to sponsor a user operation.
What is an ERC-20 Paymaster?
An ERC-20 Paymaster is a specific type of paymaster that is willing to sponsor the gas fees for a user operation if and only if the smart contract wallet pays the paymaster for it in an ERC-20 token like USDC, DAI, etc. In effect, this allows smart contract wallets to pay for gas fees purely in ERC-20 tokens and means, if designed correctly, they never need to hold any native tokens like ETH.
How do I use Pimlico's ERC-20 Paymaster?
We wrote a tutorial that takes you through the whole flow of deploying a Safe account and sending your first user operation sponsored with USDC.
We also have a how-to guide that explains how to use the ERC-20 Paymaster in your app's flow.
What is the contract address of the ERC-20 Paymaster?
The currently supported tokens are listed here.
Theoretically, we can support any token on any EVM chains that have Chainlink interface compatible oracle support. If you have a token that you would like supported, please reach out to us!
Where can I find the ERC-20 Paymaster contract?
You can find the contract source code here.
How can I use a token that is not currently supported by Pimlico?
Please get in touch with us. For enterprise customers we will do what we can to see if we can add support for the token you are interested in.
Does Pimlico take a fee?
Yes, the owner takes a fee that is baked into the exchangeRate returned by the API. This markup serves to compensate the onwer for maintaining the infrastructure and covering risks associated with price fluctuations and slippage risk.