next-forge uses Stripe by default for payments and billing. Implementing Stripe in your project is straightforward.

In-App Purchases

You can use Stripe anywhere in your app by importing the stripe object like so:

page.tsx
import { stripe } from '@repo/payments';

// ...

await stripe.prices.list();

Webhooks

Stripe webhooks are handled in the POST /webhooks/stripe route in the api app. This route constructs the event and then switches on the event type to determine how to process the event.

Local Development

To test webhooks locally, we’ve configured the Stripe CLI to forward webhooks to your local server. This will start automatically when you run pnpm dev.

Anti-Fraud

As your app grows, you will inevitably encounter credit card fraud. Stripe Radar is enabled by default if you integrate payments using their SDK as described above. This provides a set of tools to help you detect and prevent fraud.

Stripe Radar supports more advanced anti-fraud features if you embed the Stripe JS script in every page load. This is not enabled by default in next-forge, but you can add it as follows:

1

Edit the layout

Edit apps/app/app/layout.tsx and add <Script src="https://js.stripe.com/v3/" /> after the opening <html> tag and before the opening <body> tag. You will also need to add import Script from 'next/script'

import '@repo/design-system/styles/globals.css';
import { DesignSystemProvider } from '@repo/design-system';
import { fonts } from '@repo/design-system/lib/fonts';
import type { ReactNode } from 'react';
import Script from 'next/script';

type RootLayoutProperties = {
  readonly children: ReactNode;
};

const RootLayout = ({ children }: RootLayoutProperties) => (
  <html lang="en" className={fonts} suppressHydrationWarning>
    <Script src="https://js.stripe.com/v3/" />
    <body>
      <DesignSystemProvider>{children}</DesignSystemProvider>
    </body>
  </html>
);

export default RootLayout;
2

Add script to the website

Add the same script to the website in apps/web/app/layout.tsx.

3

Prevent common fraud patterns with Arcjet

Prevent common fraud patterns by using Arcjet IP address analysis to block requests from VPNs and proxies. These are commonly used by fraudsters to hide their location, but have legitimate uses as well so are not blocked by default. You could simply block these users, or you could adjust the checkout process to require approval before processing their payment.

For example, in apps/app/app/(authenticated)/layout.tsx you could add this after the call to aj.protect():

import { redirect } from 'next/navigation';
// ...

if (
  decision.ip.isHosting() ||
  decision.ip.isVpn() ||
  decision.ip.isProxy() ||
  decision.ip.isRelay()
) {
  // The IP is from a hosting provider, VPN, or proxy. We can check the name
  // of the service and customize the response
  if (decision.ip.hasService()) {
    if (decision.ip.service !== 'Apple Private Relay') {
      // We trust Apple Private Relay because it requires an active iCloud
      // subscription, so deny all other VPNs
      redirect('/vpn-blocked');
    }
  } else {
    // The service name is not available, but we still think it's a VPN
    redirect('/vpn-blocked');
  }
}

In this case we are providing a friendly redirect to a page that explains why the user is being blocked (which you would need to create). You could also return a more generic error message. See the Arcjet documentation for more advanced examples.