# Accept stablecoins in 5 minutes
This guide adds stablecoin payment support to an API. The same pattern works for Express, Next.js, Fastify, and Hono.
## 1. Install the middleware
```bash
npm install @parallel-protocol/x402
```
Install your framework separately — they are optional peer dependencies:
```bash
npm install express # or: next · fastify · hono
```
## 2. Add the middleware
Point the middleware at the facilitator, then declare which routes are paid, at what price, on which network, and where funds should settle.
```ts
import express from "express";
import { paymentMiddleware } from "@parallel-protocol/x402/express";
const app = express();
app.use(
paymentMiddleware({
facilitator: { url: "https://facilitator.parallel.best" },
routes: {
"/api/data": { price: "0.01", network: "base", payTo: "0xYourAddress" },
},
}),
);
app.get("/api/data", (req, res) => {
res.json({ data: "protected content" });
});
app.listen(3000);
```
```ts
// app/api/data/route.ts
import { withPayment } from "@parallel-protocol/x402/next";
const config = {
facilitator: { url: "https://facilitator.parallel.best" },
routes: {
"/api/data": { price: "0.10", network: "ethereum", payTo: "0xYourAddress" },
},
};
export const GET = withPayment(config, async (req) => {
return Response.json({ data: "protected content" });
});
```
```ts
import Fastify from "fastify";
import { paymentMiddleware } from "@parallel-protocol/x402/fastify";
const app = Fastify();
await app.register(
paymentMiddleware({
facilitator: { url: "https://facilitator.parallel.best" },
routes: {
"/api/data": { price: "0.05", network: "avalanche", payTo: "0xYourAddress" },
},
}),
);
app.get("/api/data", async () => ({ data: "protected content" }));
```
```ts
import { Hono } from "hono";
import { paymentMiddleware } from "@parallel-protocol/x402/hono";
const app = new Hono();
app.use(
paymentMiddleware({
facilitator: { url: "https://facilitator.parallel.best" },
routes: {
"/api/data": { price: "0.01", network: "base", payTo: "0xYourAddress" },
},
}),
);
app.get("/api/data", (c) => c.json({ data: "protected content" }));
```
That's it. Your API now charges $0.01 per request to `/api/data`. Agents pay in any [supported stablecoin](/agents/x402/concepts#supported-stablecoins) — funds settle directly to the wallet address you configured.
**No signup. No platform fee. Funds settle straight to your wallet.**
:::tip
`price` is a string parsed at the token's decimals (18 for USDp by default). For a USDC-denominated price, set `decimals: 6` on the route. See the [route configuration](/agents/x402/api-reference#routeconfig).
:::
## 3. What happens behind the scenes
When an agent calls your endpoint with a signed payment header:
1. The middleware sends the payload to the facilitator's `/x402/verify` endpoint — an instant, off-chain signature check.
2. If valid, **your handler runs** and produces the response.
3. If your handler returns a 2xx, the middleware calls `/x402/settle` — the on-chain transfer happens.
4. If your handler fails, **no settlement happens** — the agent is not charged.
Read more: [The verify / settle flow](/agents/x402/verify-vs-settle).
## Next steps
* [Concepts: how routing, fees, and gas work](/agents/x402/concepts)
* [Migrate from Coinbase x402 in one line](/agents/recipes/migrate-from-coinbase-x402)
* [API reference](/agents/x402/api-reference)