WBTC source representation
Wrapped Bitcoin is classified as a wrapped asset for this route. WBTC uses a wrapped contract asset on zkSync Era. The recorded zkSync Era representation uses 8 decimal places. WBTC leaves through a custodial wrapper contract with token approval and source-chain gas; no native Bitcoin UTXO is spent by that transfer.
zkSync Era to Base L2 handoff
This route crosses two L2 execution environments. zkSync Era settles to ethereum, while Base settles to ethereum; each side keeps its own gas balance, token contracts, transaction hash, and settlement progress.
WBTC destination representation
Wrapped Bitcoin is classified as a wrapped asset for this route. WBTC uses a wrapped contract asset on Base. The Base side is contract-tracked rather than a native gas 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.
Base receipt-side execution
Base is a L2 EVM network in the Ethereum ecosystem. ETH pays destination-side network gas on Base. EVM 0x account address A Base receipt belongs to the Base L2 balance and token contract, not Ethereum L1; later activity needs ETH specifically on Base.
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.
WBTC unwrap or exchange input 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 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 Base bridge mistakes
Route-specific mistakes include sending on a network other than zkSync Era; using a destination that is not valid for Base; 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. WBTC leaves through a custodial wrapper contract with token approval and source-chain gas; no native Bitcoin UTXO is spent by that transfer. A Base receipt belongs to the Base L2 balance and token contract, not Ethereum L1; later activity needs ETH specifically on Base. 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.