Building a SaaS with Stripe Payments

Building a successful SaaS requires a robust payment system. Stripe makes it easy to accept payments, manage subscriptions, and handle billing.

Setting Up Stripe

First, install the Stripe SDK:

npm install stripe @stripe/stripe-js

Create a Stripe instance on the server:

import Stripe from "stripe";

export const stripe = new Stripe(process.env.STRIPE_SECRET_KEY!, {
  apiVersion: "2024-12-18.acacia",
});

Creating a Subscription

To create a subscription, you need to:

1. Create a customer
2. Attach a payment method
3. Create the subscription

const subscription = await stripe.subscriptions.create({
  customer: customerId,
  items: [{ price: priceId }],
  payment_behavior: "default_incomplete",
  expand: ["latest_invoice.payment_intent"],
});

Handling Webhooks

Webhooks are essential for keeping your database in sync:

export async function POST(req: Request) {
  const body = await req.text();
  const sig = req.headers.get("stripe-signature")!;

  const event = stripe.webhooks.constructEvent(body, sig, webhookSecret);

  switch (event.type) {
    case "customer.subscription.created":
      // Handle new subscription
      break;
    case "invoice.paid":
      // Handle successful payment
      break;
  }
}

Best Practices

• Always use webhooks for critical business logic
• Store Stripe IDs in your database
• Implement proper error handling
• Test with Stripe CLI locally