Installation

Install and configure the 1inch Cross-Chain SDK

Package Installation

Install the SDK using your preferred package manager:

npm

npm install @1inch/cross-chain-sdk

Peer Dependencies

The SDK has one optional peer dependency:

• assert (^2.0.0) - Optional, used for Node.js environments

Most projects won’t need to install this manually as it’s typically included in Node.js environments.

Requirements

• Node.js: Version 18.16.0 or higher
• TypeScript: Version 5.x recommended (if using TypeScript)

Get Your API Key

Before initializing the SDK, you’ll need an authentication key from the 1inch Developer Portal:

1. Visit the Developer Portal

   Go to https://portal.1inch.dev and sign up for a free account

2. Create an API Key

   Navigate to the API Keys section and generate a new key for your project

3. Store Securely

   Save your API key in environment variables - never commit it to version control

Keep your API key secure. Don’t expose it in client-side code or commit it to public repositories.

Basic SDK Initialization

Here’s how to initialize the SDK with Web3.js:

import { SDK, PrivateKeyProviderConnector } from '@1inch/cross-chain-sdk'
import Web3 from 'web3'

const privateKey = process.env.PRIVATE_KEY // '0x...'
const rpc = 'https://ethereum-rpc.publicnode.com'
const authKey = process.env.AUTH_KEY // Get from 1inch Developer Portal

const web3 = new Web3(rpc)
const walletAddress = web3.eth.accounts.privateKeyToAccount(privateKey).address

const sdk = new SDK({
    url: 'https://api.1inch.com/fusion-plus',
    authKey,
    blockchainProvider: new PrivateKeyProviderConnector(privateKey, web3)
})

Alternative: Ethers.js Initialization

If you prefer using ethers.js, here’s the setup:

import { SDK, PrivateKeyProviderConnector } from '@1inch/cross-chain-sdk'
import { JsonRpcProvider } from 'ethers'

const privateKey = process.env.PRIVATE_KEY
const nodeUrl = 'https://ethereum-rpc.publicnode.com'
const authKey = process.env.AUTH_KEY

const ethersRpcProvider = new JsonRpcProvider(nodeUrl)

// Create a Web3-compatible provider wrapper
const ethersProviderConnector = {
    eth: {
        call(transactionConfig) {
            return ethersRpcProvider.call(transactionConfig)
        }
    },
    extend() {}
}

const sdk = new SDK({
    url: 'https://api.1inch.com/fusion-plus',
    authKey,
    blockchainProvider: new PrivateKeyProviderConnector(
        privateKey,
        ethersProviderConnector
    )
})

Read-Only SDK (No Blockchain Provider)

If you only need to query quotes and don’t need to create orders, you can initialize without a blockchain provider:

import { SDK } from '@1inch/cross-chain-sdk'

const sdk = new SDK({
    url: 'https://api.1inch.com/fusion-plus',
    authKey: process.env.AUTH_KEY
    // No blockchainProvider needed for read-only operations
})

// You can now get quotes
const quote = await sdk.getQuote({
    srcChainId: 1,
    dstChainId: 56,
    srcTokenAddress: '0x...',
    dstTokenAddress: '0x...',
    amount: '1000000',
    walletAddress: '0x...'
})

The blockchain provider is only required when creating and submitting orders. Quote queries work without it.

Configuration Options

The SDK constructor accepts the following options:

Parameter	Type	Required	Description
url	string	Yes	1inch Fusion+ API endpoint
authKey	string	Yes	Your API key from the Developer Portal
blockchainProvider	ProviderConnector	No	Provider for signing transactions (required for order creation)

Next Steps

Now that you have the SDK installed and configured, you’re ready to execute your first cross-chain swap:

Quickstart Guide

Follow our step-by-step guide to execute your first cross-chain swap