ENS contest - Chom's results

Use ERC721 instead of ERC1155

https://github.com/code-423n4/2022-07-ens/blob/main/contracts/wrapper/ERC1155Fuse.sol

ERC721 tend to use less gas than ERC1155

Transfer event doesn't has an extra amount field which save an extra gas.

You are using ERC1155 to act as an ERC721 (Only max balance per id = 1 eg every tokenId is unique)

Which mean you not need the ERC1155 functionality.

Consider using custom errors instead of revert strings

This reduce gas cost as show here https://forum.openzeppelin.com/t/a-collection-of-gas-optimisation-tricks/19966/5

Solidity 0.8.4 introduced custom errors. They are more gas efficient than revert strings, when it comes to deployment cost as well as runtime cost when the revert condition is met. Use custom errors instead of revert strings for gas savings.

Any require statement in your code can be replaced with custom error for example,

https://github.com/code-423n4/2022-07-ens/blob/ff6e59b9415d0ead7daf31c2ed06e86d9061ae22/contracts/wrapper/ERC1155Fuse.sol#L199

require(to != address(0), "ERC1155: transfer to the zero address");

Can be replaced with

// declare error before contract declaration
error TransferToZeroAddress();

if (to == address(0)) revert TransferToZeroAddress();