ETH Barcelona Hackathon Project
We have implemented a Paymaster system to cover the transaction fees associated with voting on governance proposals. This approach aims to democratize and incentivize voting by allowing users to vote without having to pay transaction fees. The Paymaster is funded either from the DAO treasury or from another designated address.
To ensure sustainability, we have set a limit on the sponsored transaction fees. For example, we may cover transaction fees up to a maximum of $100 USD per proposal. To calculate the total amount of transaction fees incurred for each proposal, we have integrated with the API3 service. This allows us to accurately determine the fees associated with each proposal and ensure the Paymaster remains within the predefined limits. you can find more technical details here contracts
We encountered several challenges while implementing our voting system. One significant issue we faced was related to the usage of block.timestamp for defining the start and end of the voting period. Initially, we expected the timestamps to be in the Unix timestamp format, as commonly used on Layer 1 (L1) blockchains.
However, the block.timestamp value on ZkSync seems to have a different format or representation. This inconsistency caused compatibility issues and resulted in incorrect time calculations for the start and end of the voting period. As a result, the system was unable to accurately determine the voting duration.
We used wagmi library and ethers to connect users to our app with their wallets. We experienced a technical challenge while trying to employ the Paymaster and send transaction with Metamask through the Ethers and wagmi libraries.
Our objective was to engage with contracts and use Paymaster to avoid user paying gas fees, for which we followed the examples set by zkSync example repositories. In those instances, a wallet object is created by the zkSync util library.
Nevertheless, we faced a hiccup when we attempted to utilize a signer, which was generated by WAGMI following a connection with Metamask. This led to an error message specifying:
zksync client.js:1 Error: invalid object key - customData (argument="transaction:customData", value=...). This implies that the customData included in the transaction might be causing the issue.
This was not a blocker, because voting uses burner-wallets, we implemented a solution using single-use wallets, stored in the browser's memory, which satisfactorily bypassed this hurdle.
However, our goal is to seamlessly incorporate Paymaster with the regular wallet to improve efficiency across all functionalities of the smart-contracts.