ETH input identity and handling
Ethereum is classified as a native asset for this route. ETH uses a native asset on zkSync Era. The recorded zkSync Era representation uses 18 decimal places. Native ETH can fund both transfer value and gas on its selected network. If the source is WETH or another tokenized form, approval and unwrap or exchange logic differ.
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.
WBTC wrapped-token output check
WBTC is a custodial tokenized Bitcoin representation on smart-contract networks. Its transfers use token contracts and approvals rather than native Bitcoin inputs and outputs. On this route WBTC is the destination token on Optimism. Its token balance, approvals, and contract transfer behavior are separate from the native coin used for network gas.
Optimism destination 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.
WBTC output identity and receiving
Wrapped Bitcoin is classified as a wrapped asset for this route. WBTC uses a wrapped contract asset on Optimism. The recorded Optimism representation uses 8 decimal places. WBTC arrives as a wrapper-contract token and must not be sent onward to a native Bitcoin address without an explicit unwrap or bridge path.
zkSync Era source 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.
EVM-to-EVM execution boundary
zkSync Era and Optimism can use the same 0x address syntax, but they are separate networks with different chain identifiers, gas balances, token contracts, and transaction histories. The recorded settlement context includes ethereum, so L1 and L2 confirmation behavior should not be assumed identical.
Mistakes specific to ETH zkSync Era to WBTC Optimism
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. Native ETH can fund both transfer value and gas on its selected network. If the source is WETH or another tokenized form, approval and unwrap or exchange logic differ. 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. WBTC arrives as a wrapper-contract token and must not be sent onward to a native Bitcoin address without an explicit unwrap or bridge path.