Cloudflare Workers

Better Payment only uses fetch and WebCrypto, so it runs in a Worker without the nodejs_compat flag. toFetchHandler turns the payment handler into a Worker fetch function.

1. Add your keys as secretsCopy Anchor Link

npx wrangler secret put IYZICO_API_KEY
npx wrangler secret put IYZICO_SECRET_KEY

2. Create the WorkerCopy Anchor Link

// src/index.ts
import { betterPayment, iyzico, toFetchHandler } from 'better-payment';

interface Env {
  IYZICO_API_KEY: string;
  IYZICO_SECRET_KEY: string;
}

export default {
  fetch(request: Request, env: Env): Promise<Response> {
    const payment = betterPayment({
      mode: 'sandbox',
      providers: {
        iyzico: iyzico({ apiKey: env.IYZICO_API_KEY, secretKey: env.IYZICO_SECRET_KEY }),
      },
    });
    return toFetchHandler(payment)(request);
  },
};

Workers pass secrets in env, not process.env, so the instance is created inside fetch. Creating it is cheap: it only reads the configuration.

3. Start a paymentCopy Anchor Link

The routes are served under /api/pay, so the frontend calls them directly:

const res = await fetch('/api/pay/iyzico/payment/init-3ds', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify(paymentRequest),
});

The typed client (better-payment/client) wraps the same routes.

4. Callback URLsCopy Anchor Link

Set callbackUrl to https://yoursite.com/api/pay/<provider>/payment/complete-3ds. The handler verifies the callback, calls onCallback and redirects the customer with callbackRedirect.

For PayTR, set the notification URL in the PayTR panel to https://yoursite.com/api/pay/paytr/callback.

IdempotencyCopy Anchor Link

The default idempotency store keeps duplicate-callback and Idempotency-Key records in memory, and every isolate has its own memory. Pass a shared store in production. See edge runtimes for options. On Workers, Durable Objects or D1 can implement the atomic setIfAbsent; Workers KV cannot, because it is eventually consistent.