@armory-sh/middleware-express

Armory x402 SDK — Payment middleware for Express v5. Accept x402 payments from any client in your Express app. 100% compatible with Coinbase x402 SDKs.

Documentation | License

Installation

bun add @armory-sh/middleware-express

Why Armory?

Armory enables HTTP API payments via EIP-3009 transferWithAuthorization. Accept payments from any x402-compatible client—Coinbase SDK, Armory SDK, or your own implementation.

Key Exports

import {
  paymentMiddleware,
  routeAwarePaymentMiddleware,
  type PaymentConfig,
  type RouteAwarePaymentConfig,
} from '@armory-sh/middleware-express';

Quick Start

import express from 'express'
import { paymentMiddleware } from '@armory-sh/middleware-express'

const app = express()

app.use(paymentMiddleware({
  requirements: {
    scheme: 'exact',
    network: 'eip155:8453',
    amount: '1000000',
    asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913',
    payTo: '0xYourAddress...',
    maxTimeoutSeconds: 300,
    extra: {}
  }
}))

app.get('/api/data', (req, res) => {
  const payment = (req as AugmentedRequest).payment
  res.json({ payerAddress: payment?.payerAddress })
})

app.listen(3000)

Features

• x402 Compatible: Accept payments from any x402 client
• Route-Aware: Different pricing for different routes
• Multi-Network: Ethereum, Base, SKALE support
• Multi-Token: USDC, EURC, USDT, WBTC, WETH, SKL

Supported Networks

| Network | Chain ID | |---------|----------| | Ethereum | 1 | | Base | 8453 | | Base Sepolia | 84532 | | SKALE Base | 1187947933 | | SKALE Base Sepolia | 324705682 | | Ethereum Sepolia | 11155111 |

License

MIT © Sawyer Cutler