Notes
- Fast fills: relayers fill deposits on destination within minutes, then claim reimbursement via optimistic oracle
- Finality: deposit confirmation on source chain, fill within 1-10 minutes typically
- Requires ERC-20 approval to the SpokePool address on source chain
- HubPool on Ethereum only — SpokePools on all supported L2s
- On Arc (5042) the SpokePool’s
wrappedNativeToken()is the zero address, so deposit ERC-20s (USDC is0x3600000000000000000000000000000000000000), not native value
Its names in a program
On Ethereum,Across is a namespace: its contracts need no import.
Deployments
ABI
Where a line says what an address it returns is, a program that calls the function through its namespace calls that contract’s methods on the result directly:<Namespace>.<Contract>.<function>(...).<method>(...). A token’s methods are the ERC-20
functions, and its writes are SafeERC20.
AcrossHubPoolABI
import AcrossHubPoolABI from "./protocols/across/AcrossHubPoolABI.json"; Speaks for: hubPool.
liquidityUtilizationCurrent(address l1Token) returns (uint256)pooledTokens(address l1Token) view returns (address lpToken, bool isEnabled, uint32 lastLpFeeUpdate, int256 utilizedReserves, uint256 liquidReserves, uint256 undistributedLpFees):lpTokenis a token
AcrossSpokePoolABI
import AcrossSpokePoolABI from "./protocols/across/AcrossSpokePoolABI.json"; Speaks for: spokePool.
depositV3(address depositor, address recipient, address inputToken, address outputToken, uint256 inputAmount, uint256 outputAmount, uint256 destinationChainId, address exclusiveRelayer, uint32 quoteTimestamp, uint32 fillDeadline, uint32 exclusivityParameter, bytes message) payabledeposit(bytes32 depositor, bytes32 recipient, bytes32 inputToken, bytes32 outputToken, uint256 inputAmount, uint256 outputAmount, uint256 destinationChainId, bytes32 exclusiveRelayer, uint32 quoteTimestamp, uint32 fillDeadline, uint32 exclusivityParameter, bytes message) payable
Next steps
- Protocols: the other protocols, by what they do.
- Protocols and tokens: calling a contract by its namespace, or through its ABI.
- Glossary: the words these pages use, in plain terms.