AxonAxon

Installation

Install the Axon TypeScript SDK and configure your project.

Installation

The @axonfi/sdk package provides a typed client for signing payment intents and interacting with the Axon relay network. It works in Node.js 20+ and any modern bundler environment.

Install

# npm
npm install @axonfi/sdk
 
# yarn
yarn add @axonfi/sdk
 
# pnpm
pnpm add @axonfi/sdk

Peer Dependency

The SDK requires viem v2 or later as a peer dependency. If you do not already have it installed:

npm install viem@^2.0.0

viem is used internally for ABI encoding, EIP-712 typed data signing, and address utilities. It is listed as a peer dependency so your project controls the exact version and avoids duplicate bundles.

Module Format

The package ships as both ESM and CJS with full TypeScript declaration files. No additional @types package is needed.

  • ESM — import { AxonClient } from "@axonfi/sdk"
  • CJS — const { AxonClient } = require("@axonfi/sdk")

Basic Setup

Option 1: Encrypted Keystore (Recommended)

If you downloaded an encrypted keystore file from the dashboard, decrypt it at startup:

import { AxonClient, decryptKeystore, Chain } from '@axonfi/sdk';
import fs from 'fs';
 
const keystore = fs.readFileSync(process.env.AXON_BOT_KEYSTORE_PATH!, 'utf8');
const privateKey = await decryptKeystore(keystore, process.env.AXON_BOT_PASSPHRASE!);
 
const axon = new AxonClient({
  vaultAddress: '0xYourVaultAddress',
  chainId: Chain.Base,
  botPrivateKey: privateKey,
});
 
console.log('Bot address:', axon.botAddress);

Option 2: Plain Private Key (Not Recommended)

import { AxonClient, Chain, USDC } from '@axonfi/sdk';
 
const axon = new AxonClient({
  vaultAddress: '0xYourVaultAddress',
  chainId: Chain.Base,
  botPrivateKey: process.env.AXON_BOT_PRIVATE_KEY as `0x${string}`,
});

The keystore file uses the standard Ethereum V3 format (scrypt + AES-128-CTR), same as MetaMask and Geth. It is safe to store in cloud backups or password managers — useless without the passphrase.

Never hardcode your bot private key in source code. Use environment variables or a secrets manager. The key is used only to sign EIP-712 intents locally and never leaves your process.

Environment Variables

A recommended .env file for local development:

# Option 1: Encrypted keystore (recommended)
AXON_BOT_KEYSTORE_PATH=./axon-bot-0xABCD1234.json
AXON_BOT_PASSPHRASE=<your-passphrase>
 
# Option 2: Plain private key (not recommended)
# AXON_BOT_PRIVATE_KEY=0x...
 
AXON_VAULT_ADDRESS=0x...
AXON_CHAIN_ID=84532

USDC Addresses

The SDK exports a USDC constant mapping chain IDs to canonical USDC contract addresses:

import { USDC } from '@axonfi/sdk';
 
USDC[8453]; // 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 (Base)
USDC[42161]; // 0xaf88d065e77c8cC2239327C5EDb3A432268e5831 (Arbitrum)
USDC[84532]; // 0x036CbD53842c5426634e7929541eC2318f3dCF7e (Base Sepolia)

Next Steps