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Use Hono for lightweight services and keep 4Mica payment handling in the Node layer that owns your paid route. The stable 4Mica server integration is Express middleware, so mount it beside your Hono app when the paid route needs automatic verify and settle behavior.
This integration is not stable yet. For now, use the NodeJS quick start for the supported implementation.

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Prerequisites

  • Node.js 18 or later.
  • A Hono service running on Node.
  • A seller wallet address for payTo.
  • A buyer wallet with deposited collateral for testing paid calls.

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Install

npm install hono @hono/node-server express @4mica/x402 @x402/fetch viem

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Create wallet

For wallet setup, see Wallet. 
PRIVATE_KEY=0xYourPrivateKey
PAY_TO=0xYourSellerAddress
Use the private key only for buyer-side signing in trusted server-side code. Use PAY_TO as the seller address advertised by protected routes.

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Deposit collateral

Deposit collateral for the buyer wallet before it calls your Hono service. Use the same network in the buyer scheme and route payment requirements. To learn more about collateral setup, see Deposits and Withdrawals.

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Protect a route

Run your paid API route through the 4Mica middleware and keep the rest of your service in Hono. 
import express from "express";
import { Hono } from "hono";
import { serve } from "@hono/node-server";
import { paymentMiddlewareFromConfig } from "@4mica/x402/server/express";

const paid = express();
paid.use(express.json());

paid.use(
  paymentMiddlewareFromConfig(
    {
      "GET /premium-content": {
        accepts: {
          scheme: "4mica-credit",
          price: "$0.10",
          network: "eip155:84532",
          payTo: process.env.PAY_TO ?? "0xYourAddress",
        },
        description: "Access to premium Hono content",
      },
    },
  ),
);

paid.get("/premium-content", (req, res) => {
  res.json({ message: "Paid content from Hono's Node service" });
});

paid.listen(3030);

const app = new Hono();
app.get("/", (c) => c.text("Hono app"));

serve({ fetch: app.fetch, port: 3000 });

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Support payment

import { wrapFetchWithPaymentFromConfig } from "@x402/fetch";
import { FourMicaEvmScheme } from "@4mica/x402/client";
import { privateKeyToAccount } from "viem/accounts";

const account = privateKeyToAccount(process.env.PRIVATE_KEY as `0x${string}`);
const scheme = await FourMicaEvmScheme.create(account);

const fetchWithPayment = wrapFetchWithPaymentFromConfig(fetch, {
  schemes: [{ network: "eip155:84532", client: scheme }],
});

const response = await fetchWithPayment("http://localhost:3030/premium-content");
const data = await response.json();