Configuration

Configuration options and settings for @tetherto/wdk-protocol-swap-velora-evm

Swap Service Configuration

The VeloraProtocolEvm accepts a configuration object that defines fee controls and behavior:

import VeloraProtocolEvm from '@tetherto/wdk-protocol-swap-velora-evm'
import { WalletAccountEvm } from '@tetherto/wdk-wallet-evm'

// Create wallet account first
const account = new WalletAccountEvm(seedPhrase, "0'/0/0", {
  provider: 'https://ethereum-rpc.publicnode.com'
})

// Create swap service with configuration
const swapProtocol = new VeloraProtocolEvm(account, {
  swapMaxFee: 200000000000000n // Optional: Max swap fee in wei
})

Account Configuration

The swap service uses the wallet account configuration for network access and signing:

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

// Full access account
const account = new WalletAccountEvm(
  seedPhrase,
  "0'/0/0",
  {
    provider: 'https://ethereum-rpc.publicnode.com'
  }
)

// Read-only account (quotes only)
const readOnly = new WalletAccountReadOnlyEvm(
  '0xYourAddress',
  {
    provider: 'https://ethereum-rpc.publicnode.com'
  }
)

// Create swap service
const swapProtocol = new VeloraProtocolEvm(account, {
  swapMaxFee: 200000000000000n
})

Configuration Options

Swap Max Fee

The swapMaxFee option sets an upper bound for total gas costs to prevent excessive fees.

Type: bigint (optional) Unit: Wei

Examples:

const config = {
  // Cap total gas fee to 0.0002 ETH (in wei)
  swapMaxFee: 200000000000000n,
}

// Usage example
try {
  const result = await swapProtocol.swap({
    tokenIn: '0xdAC17F958D2ee523a2206206994597C13D831ec7', // USD₮ (6 decimals)
    tokenOut: '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2', // WETH (18 decimals)
    tokenInAmount: 1000000n
  })
} catch (error) {
  if (error.message.includes('max fee')) {
    console.error('Swap stopped: Fee too high')
  }
}

ERC‑4337 (Account Abstraction) Configuration

When using ERC‑4337 smart accounts (@tetherto/wdk-wallet-evm-erc-4337), you can override fee behavior per swap and specify a paymaster token:

import { WalletAccountEvmErc4337 } from '@tetherto/wdk-wallet-evm-erc-4337'

const aa = new WalletAccountEvmErc4337(seedPhrase, "0'/0/0", {
  chainId: 1,
  provider: 'https://arb1.arbitrum.io/rpc',
  bundlerUrl: 'YOUR_BUNDLER_URL',
  paymasterUrl: 'YOUR_PAYMASTER_URL'
})

const swapAA = new VeloraProtocolEvm(aa, { swapMaxFee: 200000000000000n })

const result = await swapAA.swap({
  tokenIn: '0xTokenIn',
  tokenOut: '0xTokenOut',
  tokenInAmount: 1000000n
}, {
  paymasterToken: 'USDT', // Token used to pay for gas
  swapMaxFee: 200000000000000n // Per‑swap override
})

Paymaster Token (ERC‑4337)

The paymasterToken option indicates which token the paymaster should use to sponsor gas.

Type: string (optional) Format: Token symbol or address

Example:

const result = await swapAA.swap({
  tokenIn: '0xdAC17F...ec7',
  tokenOut: '0xC02a...6Cc2', // WETH
  tokenInAmount: 1000000n
}, {
  paymasterToken: 'USDT'
})

Network Support

velora supports multiple EVM networks (e.g., Ethereum, Polygon, Arbitrum). Ensure your account is configured with a valid provider for the target network.

// Ethereum Mainnet
const eth = new WalletAccountEvm(seedPhrase, "0'/0/0", {
  provider: 'https://ethereum-rpc.publicnode.com'
})

// Polygon
const polygon = new WalletAccountEvm(seedPhrase, "0'/0/0", {
  provider: 'https://polygon-bor-rpc.publicnode.com'
})

Swap Options

When calling swap, provide the swap parameters:

const swapOptions = {
  tokenIn: '0xTokenIn',          // ERC‑20 to sell
  tokenOut: '0xTokenOut',        // ERC‑20 to buy
  tokenInAmount: 1000000n,       // exact input (base units)
  // OR
  // tokenOutAmount: 1000000n,   // exact output (base units)
  to: '0xRecipient'              // optional recipient (defaults to your address)
}

const result = await swapProtocol.swap(swapOptions)

Parameters

• tokenIn (string): ERC‑20 address to sell

• tokenOut (string): ERC‑20 address to buy

• tokenInAmount (bigint, optional): exact input amount in token base units

• tokenOutAmount (bigint, optional): exact output amount in token base units

• to (string, optional): recipient address (defaults to account address)

Note: Use either tokenInAmount OR tokenOutAmount, not both.

Node.js Quickstart

Get started with WDK in a Node.js environment

WDK velora Swap Protocol API

Get started with WDK's velora Swap Protocol API

WDK velora Swap Protocol Usage

Get started with WDK's velora Swap Protocol usage

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