i_got_hacked-G.md

Multiple mappings can be combined into a single mapping of key to a struct.

• https://github.com/code-423n4/2022-10-zksync/blob/main/ethereum/contracts/zksync/Storage.sol#L87-L89
• https://github.com/code-423n4/2022-10-zksync/blob/main/ethereum/contracts/common/AllowList.sol#L26-L30
• https://github.com/code-423n4/2022-10-zksync/blob/main/ethereum/contracts/zksync/Storage.sol#L22-L23

require() statements that use && should be split

• https://github.com/code-423n4/2022-10-zksync/blob/main/ethereum/contracts/common/AllowList.sol#L96-L99

Use calldata instead of memory for external functions where the function argument is read-only

• https://github.com/code-423n4/2022-10-zksync/blob/main/zksync/contracts/ExternalDecoder.sol#L10
• https://github.com/code-423n4/2022-10-zksync/blob/main/zksync/contracts/ExternalDecoder.sol#L15
• https://github.com/code-423n4/2022-10-zksync/blob/main/zksync/contracts/L2ContractHelper.sol#L6
• https://github.com/code-423n4/2022-10-zksync/blob/main/ethereum/contracts/common/L2ContractHelper.sol#L6

internal functions only called once can be inlined to save gas

• https://github.com/code-423n4/2022-10-zksync/blob/main/ethereum/contracts/zksync/facets/Executor.sol#L349

Adding a return statement when the function defines a named return variable, is redundant

• https://github.com/code-423n4/2022-10-zksync/blob/main/ethereum/contracts/zksync/facets/Executor.sol#L67-L78