WETH source representation
WETH is classified as a wrapped asset for this route. WETH uses a wrapped contract asset on zkSync Era. The recorded zkSync Era representation uses 18 decimal places. WETH leaves through a wrapper contract and needs native chain gas. A WETH token balance cannot pay the gas required to submit its own transfer.
zkSync Era to Optimism L2 handoff
This route crosses two L2 execution environments. zkSync Era settles to ethereum, while Optimism settles to ethereum; each side keeps its own gas balance, token contracts, transaction hash, and settlement progress.
WETH destination representation
WETH is classified as a wrapped asset for this route. WETH uses a wrapped contract asset on Optimism. The recorded Optimism representation uses 18 decimal places. WETH arrives as a token contract balance. It may need an explicit unwrap before becoming native ETH and cannot itself pay transaction gas.
Optimism receipt-side execution
Optimism is a L2 EVM network in the Ethereum ecosystem. ETH pays destination-side network gas on Optimism. EVM 0x account address An OP Mainnet receipt belongs to the OP Stack L2 and needs ETH on that network for later activity; it is not an Ethereum L1 balance.
zkSync Era deposit-side execution
zkSync Era is a L2 EVM network in the Ethereum ecosystem. ETH pays source-side network gas on zkSync Era. EVM 0x account address A zkSync Era source executes in EraVM with native account-abstraction behavior and ETH fees before proof settlement to Ethereum.
WETH unwrap or exchange input check
WETH is a contract wrapper for ETH. It can be transferred as a token but cannot replace the native gas balance required by the network. On this route WETH is the source token on zkSync Era. Its token balance, approvals, and contract transfer behavior are separate from the native coin used for network gas.
zkSync Era to Optimism bridge mistakes
Route-specific mistakes include sending on a network other than zkSync Era; using a destination that is not valid for Optimism; running out of ETH before the source transaction is submitted; treating a wrapped token as the native gas asset. A zkSync Era source executes in EraVM with native account-abstraction behavior and ETH fees before proof settlement to Ethereum. WETH leaves through a wrapper contract and needs native chain gas. A WETH token balance cannot pay the gas required to submit its own transfer. An OP Mainnet receipt belongs to the OP Stack L2 and needs ETH on that network for later activity; it is not an Ethereum L1 balance. WETH arrives as a token contract balance. It may need an explicit unwrap before becoming native ETH and cannot itself pay transaction gas.