1inch Intent Swap SDK Examples

Production-quality TypeScript examples demonstrating intent-based swaps (Fusion mode) on EVM chains and Solana using the 1inch Fusion SDKs.

What is Intent Swap (Fusion)?

Intent-based swaps allow you to:

• Swap without paying gas - Resolvers cover execution costs
• Get MEV protection - No front-running or sandwich attacks
• Achieve optimal rates - Dutch auction ensures competitive pricing

Provider-Agnostic Architecture

The EVM examples demonstrate that the Fusion SDK is truly library-agnostic. The architecture separates concerns:

┌─────────────────────┐     ┌─────────────────────┐
│  Provider (ethers)  │     │  Provider (viem)    │
│  - getTokenBalance  │     │  - getTokenBalance  │
│  - approveToken     │     │  - approveToken     │
│  - web3Like adapter │     │  - web3Like adapter │
└──────────┬──────────┘     └──────────┬──────────┘
           │                           │
           └─────────┬─────────────────┘
                     │
                     ▼
        ┌───────────────────────┐
        │  createFusionSDK()    │  ◀── Library-agnostic!
        │  (shared/types.ts)    │      Uses provider.web3Like
        └───────────────────────┘

To switch libraries, just change one import:

// Use ethers.js:
import { createProvider } from "./providers/ethers.js";

// OR use viem:
import { createProvider } from "./providers/viem.js";

// SDK creation is the same regardless of provider!
const provider = await createProvider(config);
const sdk = createFusionSDK(config, provider.web3Like);

Examples

EVM Examples

Script	Description	Command
src/evm/quick-start.ts	Minimal quick start	npm run quick-start
src/evm/swap-erc20.ts	Swap ERC-20 to ERC-20	npm run evm:swap-erc20
src/evm/swap-native.ts	Swap native ETH to ERC-20	npm run evm:swap-native
src/evm/swap-with-permit2.ts	Gasless approvals with Permit2	npm run evm:swap-permit2

Solana Examples

Script	Description	Command
src/solana/quick-start.ts	Minimal quick start	npm run solana:quick-start
src/solana/swap-sol-to-jup.ts	Swap native SOL to JUP	npm run solana:swap
src/solana/cancel-order.ts	Cancel an active order	npm run solana:cancel

Quick Start

Minimal Example (Recommended for First-Time Users)

For the simplest possible integration, run a quick-start example:

npm install
cp .env.example .env  # Add your API_KEY and private keys

# EVM (Ethereum)
npm run quick-start

# Solana
npm run solana:quick-start

These single-file examples demonstrate:

• src/evm/quick-start.ts — USDC → 1INCH swap on Ethereum (~65 lines)
• src/solana/quick-start.ts — SOL → JUP swap on Solana (~95 lines)

Full Setup

1. Install Dependencies

npm install

2. Configure Environment

cp .env.example .env

Edit .env with your values:

# Required: Your 1inch API key from https://business.1inch.com/portal
API_KEY=your-api-key

# EVM Configuration
EVM_PRIVATE_KEY=0x...          # Your wallet private key (with 0x prefix)
EVM_RPC_URL=                   # Optional: defaults to 1inch Web3
EVM_NETWORK_ID=1               # 1=Ethereum, 8453=Base, etc.

# Solana Configuration
SOLANA_PRIVATE_KEY=...         # Base58 or base64-encoded secret key
SOLANA_RPC_URL=                # Optional: defaults to 1inch Web3

3. Run Examples

# EVM Examples
npm run evm:swap-erc20      # Swap 1INCH → WETH
npm run evm:swap-native     # Swap ETH → USDC
npm run evm:swap-permit2    # Swap USDC → WETH with Permit2

# Solana Examples
npm run solana:swap         # Swap SOL → JUP
npm run solana:cancel       # Cancel an order

Project Structure

src/evm/
├── providers/
│   ├── interface.ts          # EVMProvider interface definition
│   ├── ethers.ts             # ethers.js implementation (~95 lines)
│   └── viem.ts               # viem implementation (~105 lines)
├── shared/
│   └── types.ts              # Shared constants, utilities, createFusionSDK()
├── swap-erc20.ts             # ERC-20 to ERC-20 swap example
├── swap-native.ts            # Native ETH to ERC-20 swap example
└── swap-with-permit2.ts      # ERC-20 swap with Permit2 example

src/solana/
├── utils/
│   └── connection.ts         # Solana connection utilities
├── swap-sol-to-jup.ts
└── cancel-order.ts

Switching Providers

Each example file has a clearly marked provider selection section at the top:

// ╔═══════════════════════════════════════════════════════════════════════════╗
// ║ PROVIDER SELECTION - Change this import to switch libraries              ║
// ╚═══════════════════════════════════════════════════════════════════════════╝
import { createProvider } from "./providers/ethers.js";
// import { createProvider } from "./providers/viem.js";

The SDK initialization is identical for both providers:

const config = loadConfig();
const provider = await createProvider(config); // Library-specific
const sdk = createFusionSDK(config, provider.web3Like); // Library-agnostic!

The EVMProvider Interface

Providers implement a minimal interface for blockchain operations:

interface EVMProvider {
  address: string; // Wallet address
  web3Like: Web3Like; // Adapter for Fusion SDK

  // Read operations
  getNativeBalance(address: string): Promise<bigint>;
  getTokenBalance(tokenAddress: string, ownerAddress: string): Promise<bigint>;
  getTokenAllowance(tokenAddress: string, ownerAddress: string, spenderAddress: string): Promise<bigint>;

  // Write operations
  approveToken(tokenAddress: string, spenderAddress: string, amount: bigint): Promise<string>;
  waitForTransaction(txHash: string): Promise<void>;
}

EVM Details

Supported Networks

Network	Chain ID	NetworkEnum
Ethereum	1	ETHEREUM
Base	8453	COINBASE
BNB Chain	56	BINANCE
Polygon	137	POLYGON
Arbitrum	42161	ARBITRUM
Optimism	10	OPTIMISM
Avalanche	43114	AVALANCHE
Gnosis	100	GNOSIS
Fantom	250	FANTOM

Token Addresses (Ethereum)

Token	Address
1INCH	0x111111111117dC0aa78b770fA6A738034120C302
WETH	0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2
USDC	0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48
Native ETH	0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE

Contract Addresses

Contract	Address
Aggregation Router V6	0x111111125421ca6dc452d289314280a0f8842a65
Permit2	0x000000000022D473030F116dDEE9F6B43aC78BA3

Solana Details

Token Addresses

Token	Mint Address	Decimals
SOL (Native)	Use Address.NATIVE	9
JUP	JUPyiwrYJFskUPiHa7hkeR8VUtAeFoSYbKedZNsDvCN	6
USDC	EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v	6

Key Differences from EVM

Aspect	EVM	Solana
Order Submission	Off-chain to relayer	On-chain escrow
Token Approval	Required (ERC-20 approve)	Not needed
Finality	~12 seconds	~400ms
Private Key Format	Hex with 0x prefix	Base58 or base64

Troubleshooting

EVM Issues

Error	Solution
"Insufficient allowance"	Run approval transaction first
"Quote expired"	Get a fresh quote before creating order
Order expires	Try larger amounts or "fast" preset

Solana Issues

Error	Solution
"Invalid PRIVATE_KEY format"	Ensure base58 or base64-encoded 64-byte key
"Insufficient funds"	Add SOL for swap amount + fees
"Blockhash not found"	Transaction expired, retry

Resources

• 1inch Developer Portal
• Fusion SDK GitHub
• Solana Fusion SDK GitHub
• Intent Swap API Docs
• ethers.js Documentation
• viem Documentation

License

MIT