Configuration

Client Options

The SteelSwapClient accepts a configuration object with the following options:

import { SteelSwapClient } from 'steelswap-sdk'

const client = new SteelSwapClient({
  baseUrl: 'https://apidev.steelswap.io', // API base URL
  timeout: 30000, // Request timeout in ms
  token: 'd82983fe50d8eae...', // Authentication token
  partner: 'eternl', // Partner identifier
  numericFormat: 'string', // Output format for numbers
  fetch: customFetch, // Custom fetch implementation
})

token

• Type: string
• Default: undefined

Authentication token sent as the token header on all API requests.

const client = new SteelSwapClient({
  token: 'd82983fe50d8eae11f3fa2dd66ddfe658420c9474a9410c44943a71937c35f07',
})

partner

• Type: Partner
• Default: undefined

Partner identifier automatically injected into swap requests (estimateSwap, buildSwap, cancelSwap). Valid values:

• '' (empty string)
• 'eternl'
• 'eternl-aggregator'
• 'eternl-browser'
• 'farmbot'
• 'lace-aggregator'
• 'yoroi-aggregator'

const client = new SteelSwapClient({
  partner: 'eternl',
})

// Partner is automatically included in swap requests
await client.estimateSwap({
  tokenA: '',
  tokenB: 'policy.asset',
  quantity: '10000000',
})

numericFormat

• Type: 'string' | 'number' | 'bigint' | 'Big'
• Default: 'string'

Controls the format of numeric values in API responses. The client is generic and TypeScript will infer the correct return types based on your choice.

// Default: strings (safest for large numbers)
const stringClient = new SteelSwapClient({ numericFormat: 'string' })
const estimate1 = await stringClient.estimateSwap({ ... })
estimate1.totalOutput // type: string

// JavaScript numbers (convenient but may lose precision for large values)
const numberClient = new SteelSwapClient({ numericFormat: 'number' })
const estimate2 = await numberClient.estimateSwap({ ... })
estimate2.totalOutput // type: number

// BigInt (for integer precision)
const bigintClient = new SteelSwapClient({ numericFormat: 'bigint' })
const estimate3 = await bigintClient.estimateSwap({ ... })
estimate3.totalOutput // type: bigint

// Big.js instances (for decimal precision and calculations)
const bigClient = new SteelSwapClient({ numericFormat: 'Big' })
const estimate4 = await bigClient.estimateSwap({ ... })
estimate4.totalOutput // type: Big
estimate4.totalOutput.times('0.997') // Big.js methods available

baseUrl

• Type: string
• Default: 'https://apidev.steelswap.io'

The base URL for the SteelSwap API.

timeout

• Type: number
• Default: 30000

Request timeout in milliseconds. Requests that take longer will be aborted.

fetch

• Type: typeof fetch
• Default: Global fetch

Custom fetch implementation. Useful for:

• Request/response logging
• Using a different HTTP client

Working with Numbers

Input

All numeric values (quantities, slippage, etc.) can be passed as:

• Strings: '10000000'
• BigInt: 10000000n
• Big.js instances: new Big('10000000')

import Big from 'big.js'

// All of these work regardless of numericFormat
await client.estimateSwap({
  tokenA: '',
  tokenB: 'policy.asset',
  quantity: '10000000', // string
})

await client.estimateSwap({
  tokenA: '',
  tokenB: 'policy.asset',
  quantity: 10000000n, // bigint
})

const amount = new Big('10000000')
await client.estimateSwap({
  tokenA: '',
  tokenB: 'policy.asset',
  quantity: amount, // Big instance
})

Output

Output format is controlled by numericFormat. Choose based on your needs:

Format	Type	Best For
'string'	string	Default, safe for any size, easy serialization
'number'	number	Simple math, small values (< 2^53)
'bigint'	bigint	Large integers, native JS support
'Big'	Big	Decimal precision, complex calculations

// Example with Big.js for calculations
const client = new SteelSwapClient({ numericFormat: 'Big' })
const estimate = await client.estimateSwap({ ... })

// Direct calculations on response values
const withSlippage = estimate.totalOutput.times('0.99')
const formatted = estimate.totalOutput.div(1_000_000).toFixed(2) // "50.00" ADA

Custom Fetch Example

const customFetch: typeof fetch = async (url, options) => {
  console.log('Request:', url)

  const response = await fetch(url, {
    ...options,
    headers: {
      ...options?.headers,
      'X-Custom-Header': 'value',
    },
  })

  console.log('Response:', response.status)
  return response
}

const client = new SteelSwapClient({
  fetch: customFetch,
})

Environment-Specific Setup

Node.js

The SDK works out of the box in Node.js 18+ which includes native fetch.

For older Node.js versions, use a fetch polyfill:

import fetch from 'node-fetch'

const client = new SteelSwapClient({
  fetch: fetch as unknown as typeof globalThis.fetch,
})

Browser

No additional setup required. The SDK uses the native fetch API.

React Native

// React Native has built-in fetch support
const client = new SteelSwapClient()