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Bridge USD₮0 EVM Configuration

Configuration options and settings for @tetherto/wdk-protocol-bridge-usdt0-evm

Bridge Protocol Configuration

The Usdt0ProtocolEvm accepts a configuration object that defines how the bridge protocol works:

import Usdt0ProtocolEvm from '@tetherto/wdk-protocol-bridge-usdt0-evm'
import { WalletAccountEvm } from '@tetherto/wdk-wallet-evm'

const account = new WalletAccountEvm(seedPhrase, {
  provider: 'https://eth-mainnet.g.alchemy.com/v2/your-api-key'
})

const bridgeProtocol = new Usdt0ProtocolEvm(account, {
  bridgeMaxFee: 1000000000000000n
})

Account Configuration

The bridge protocol uses the wallet account's configuration for blockchain access:

import { WalletAccountEvm, WalletAccountReadOnlyEvm } from '@tetherto/wdk-wallet-evm'

// Full access account
const account = new WalletAccountEvm(
  seedPhrase,
  "0'/0/0",
  {
    provider: 'https://eth-mainnet.g.alchemy.com/v2/your-api-key',
    transferMaxFee: 100000000000000
  }
)

// Read-only account
const readOnlyAccount = new WalletAccountReadOnlyEvm(
  '0x...',
  {
    provider: 'https://eth-mainnet.g.alchemy.com/v2/your-api-key'
  }
)

const bridgeProtocol = new Usdt0ProtocolEvm(account, {
  bridgeMaxFee: 1000000000000000n
})

Configuration Options

Bridge Max Fee

The bridgeMaxFee option sets a maximum limit for total bridge costs to prevent unexpectedly high fees.

Type: bigint (optional) Unit: Wei (1 ETH = 1000000000000000000 Wei)

Examples:

const config = {
  bridgeMaxFee: 1000000000000000n,
}

try {
  const result = await bridgeProtocol.bridge({
    targetChain: 'arbitrum',
    recipient: '0x...',
    token: '0x...',
    amount: 1000000000000000000n
  })
} catch (error) {
  if (error.message.includes('Exceeded maximum fee')) {
    console.error('Bridge cancelled: Fee too high')
  }
}

Provider

The provider option comes from the wallet account configuration and specifies how to connect to the blockchain.

Type: string | Eip1193Provider

Examples:

// Option 1: Using RPC URL
const account = new WalletAccountEvm(seedPhrase, {
  provider: 'https://eth-mainnet.g.alchemy.com/v2/your-api-key'
})

// Option 2: Using browser provider (e.g., MetaMask)
const account = new WalletAccountEvm(seedPhrase, {
  provider: window.ethereum
})

// Option 3: Using custom JsonRpcProvider
import { JsonRpcProvider } from 'ethers'
const account = new WalletAccountEvm(seedPhrase, {
  provider: new JsonRpcProvider('https://eth-mainnet.g.alchemy.com/v2/your-api-key')
})

ERC-4337 Configuration

When using ERC-4337 accounts, you can override configuration options during bridge operations:

const result = await bridgeProtocol.bridge({
  targetChain: 'arbitrum',
  recipient: '0x...',
  token: '0x...',
  amount: 1000000000000000000n
}, {
  paymasterToken: '0x...',
  bridgeMaxFee: 1000000000000000n
})

Paymaster Token

The paymasterToken option specifies which token to use for paying gas fees in ERC-4337 accounts.

Type: string (optional) Format: Token contract address

Example:

const result = await bridgeProtocol.bridge({
  targetChain: 'arbitrum',
  recipient: '0x...',
  token: '0x...',
  amount: 1000000000000000000n
}, {
  paymasterToken: '0x...'
})

Network Support

The bridge protocol works with EVM-compatible networks. Change the provider URL in the wallet account configuration:

// Ethereum Mainnet
const ethereumAccount = new WalletAccountEvm(seedPhrase, {
  provider: 'https://eth-mainnet.g.alchemy.com/v2/your-api-key'
})

// Arbitrum
const arbitrumAccount = new WalletAccountEvm(seedPhrase, {
  provider: 'https://arb1.arbitrum.io/rpc'
})

// Polygon
const polygonAccount = new WalletAccountEvm(seedPhrase, {
  provider: 'https://polygon-rpc.com'
})

Bridge Options

When calling the bridge method, you need to provide bridge options:

const bridgeOptions = {
  targetChain: 'arbitrum',
  recipient: '0x...',
  token: '0x...',
  amount: 1000000000000000000n,
  oftContractAddress: '0x...', // Optional: custom OFT contract
  dstEid: 30110 // Optional: custom destination endpoint ID
}

const result = await bridgeProtocol.bridge(bridgeOptions)

Target Chain

The targetChain option specifies which blockchain to bridge tokens to.

Type: string Supported values: 'ethereum', 'arbitrum', 'optimism', 'polygon', 'berachain', 'ink', 'plasma', 'conflux', 'corn', 'avalanche', 'celo', 'flare', 'hyperevm', 'mantle', 'megaeth', 'monad', 'morph', 'rootstock', 'sei', 'stable', 'unichain', 'xlayer', 'solana', 'ton', 'tron'

Recipient

The recipient option specifies the address that will receive the bridged tokens.

Type: string Format: Valid address for the target chain

Token

The token option specifies which token contract to bridge.

Type: string Format: Token contract address on the source chain

Amount

The amount option specifies how many tokens to bridge.

Type: bigint Unit: Base units of the token (e.g., for USD₮: 1 USD₮ = 1000000n)

OFT Contract Address

The oftContractAddress option overrides the default OFT (Omnichain Fungible Token) contract address used for the bridge operation.

Type: string (optional) Format: Contract address on the source chain

Example:

const result = await bridgeProtocol.bridge({
  targetChain: 'arbitrum',
  recipient: '0x...',
  token: '0x...',
  amount: 1000000000000000000n,
  oftContractAddress: '0x1234...' // Custom OFT contract
})

Destination Endpoint ID

The dstEid option overrides the default LayerZero destination endpoint ID for the target chain.

Type: number (optional)

Example:

const result = await bridgeProtocol.bridge({
  targetChain: 'solana',
  recipient: 'SolanaRecipientAddress...',
  token: '0x...',
  amount: 1000000000000000000n,
  dstEid: 30168 // Solana endpoint ID
})

Error Handling

The bridge protocol will throw errors for invalid configurations:

try {
  const result = await bridgeProtocol.bridge({
    targetChain: 'invalid-chain',
    recipient: '0x...',
    token: '0x...',
    amount: 1000000000000000000n
  })
} catch (error) {
  if (error.message.includes('not supported')) {
    console.error('Chain or token not supported')
  }
  if (error.message.includes('Exceeded maximum fee')) {
    console.error('Bridge fee too high')
  }
  if (error.message.includes('must be connected to a provider')) {
    console.error('Wallet not connected to blockchain')
  }
}

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