locker room

Substantial amount of L2 transaction gas fee is driven by L1 rollup fee. L2s are trying to enhance their calldata compression algorithm and L1 Ethereum devs are working hard for EIP-4844, but we can do better.

If you look closely to blockchain explorer such as etherscan, most users send similar calldata. So I solved the problem by making a helper smart contract called Locker Room. It's permissionless calldata cache storage for everyone. Every smart contract developers can use Locker Room to cache specific calldata. I've also uploaded example smart contracts that uses Locker Room. You can see the L1 data fee has really saved. L2 execution fee actually slightly increases because there's two more internal calls if you use Locker Room.

In conclusion, locker room is a smart contract level solution that reduces transaction fee for L2 users, so it will massively enhance user experience. Furthermore, I'm planning to expand this idea by proposing new EIP for calldata caching standard.

To demonstrate the concept, I used foundry implement and deploy smart contracts. There are two smart contracts: one is locker room smart contract, which is deployed by me, and the other one is locker room user contract, which uses locker room as a calldata cache. I deployed the smart contracts to scroll sepolia testnet.