Meta Transactions are also known as "Gasless Transactions". The concept of meta transactions allows users to interact with the decentralized applications having ONLY a public/private keys pair.
A user with an account can craft a transaction in a similar way to how the ‘normal’ transaction is created, sign it with the own private key, but instead of sending it on-chain (which is usually the last step that requires paying ETH for gas), they send it to so-called a ‘relayer’, or the actual ‘sender’.
To integrate your DApp with Meta Transactions on Matic, you can choose to go with either the following two relayers or spin up a custom solution:
- Biconomy uses the IdentityProxy/Controller pair approach
- Each user associated with his unique Proxy contract address - which acts as their identity for any on-chain transaction
- Biconomy runs their own Relayers paying Gas fee upfront which is eventually recovered from the DApp on monthly basis.
- No changes to the smart contract required
- Biconomy provides their SDK Mexa to integrate with, abstracting the process of enabling meta transactions in a DApp to a few lines of code
- Refer to Biconomy documentation for a comprehensive guidelines on usage of their SDK and steps to integrate it into your DApp.
- If you are developing your DApp on Matic, you can integrate with Biconomy on the following test-networks:
Gas Station Network (GSN)
- As described in the previous post, GSN uses a RelayHub to keep track of the decentralised network of Relayers and acts as their point of discovery
- The entire mechanism is decentralized
- Neither the Relayers not the RelayHub are controlled by the network/developer in any way
- The relays network is a free market, where relays compete based on transaction fees and quality of service, on equal grounds.
- OpenZeppelin provides tools, tutorials and guidelines on how to integrate with the Gas Station Network.
- Smart contracts are required to be modified in order for them to accept relayed calls
- The following details should get you started on building GSN powered DApps on Matic Network:
- RelayHub address:
- Writing GSN compatible smart contracts
- Building a DApp with GSN
- Starter Kit
Assuming your familiarity with the different approaches you can take to integrate meta-transactions in your DApp, and depending on weather you're migrating to meta-transactions or building fresh DApp on using it, the following links will guide you on your steps ahead: