Layer 2 solutions have emerged as a crucial component in addressing scalability issues. Optimising smart contracts for these Layer 2 chains is essential to harness their full potential. This article explores key considerations for developers working with Layer 2 solutions, focusing on cross-chain interoperability, gas fees, and frontend considerations.
Cross-Chain Interoperability
When optimising smart contracts for Layer 2 chains, developers must consider how their contracts will interact with other chains. Things like LayerZero’s OFT technology make it easier than ever to create cross-chain tokens and NFT’s.
To achieve seamless cross-chain functionality, smart contracts should implement standardised protocols for message passing and asset transfers. This may involve utilising bridge contracts or adapting to specific Layer 2 interoperability solutions. Developers should design their contracts with modularity in mind, allowing for easy integration with various cross-chain communication protocols.
Gas Fees For Deployment & Users
One of the primary advantages of L2 and Alt L1 chains is reduced gas fees. However, optimising smart contracts to fully leverage this benefit requires careful consideration.
When deploying contracts to Layer 2 chains, developers don’t need to be so concerned about a contract’s bytecode size. The cost of deployment is not significant in the same way that it is on Ethereum mainnet during peak demand.
There’s little benefit to coding the whole thing in Assembly/Yul when the cost per transaction is less than $0.01. The trade off with code readability becomes much less valuable.
Block Times & Frontend Considerations
L2’s often boast faster block times compared to Ethereum mainnet which has roughly a 13 second block window. Some L2’s offer subsecond confirmations and while this improved speed is advantageous, it also presents unique challenges for frontend development.
Smart contracts on Layer 2 chains should be optimised to handle rapid state changes. This may involve implementing more granular event emissions to allow frontends to update in real-time. Developers should also consider implementing optimistic UI updates, where the frontend reflects changes immediately while waiting for on-chain confirmation and avoiding code that pages or pings the RPC node at regular intervals.
Ideally you want a dynmaic dApp frontend which reacts instantly to events fired from the L2 contracts.
You may also find that some L2’s don’t have the same infrastructure Infura/Alchemy available that you are used to on mainnet and you are reliant on public RPC nodes that get congested at peak periods. If this is the case then your frontend may need something in place to deal with laggy responses from the RPC nodes even if the block times are faster.
