Integrate payment gateways like Stripe, PayPal, and Square with backends for payment processing, subscription management, and webhook handling. Use when building e-commerce platforms, implementing billing systems, and handling payments securely.

Payment Gateway Integration Table of Contents [Overview]( overview) [When to Use]( when to use) [Quick Start]( quick start) [Reference Guides]( reference guides) [Best Practices]( best practices) Overview Build secure payment processing systems with major payment providers (Stripe, PayPal, Square), handling transactions, subscriptions, webhooks, PCI compliance, and error scenarios across different backend frameworks. When to Use Processing customer payments Implementing subscription billing Building e commerce platforms Handling refunds and disputes Managing recurring charges Integrating payment webhooks Quick Start Minimal working example: Reference Guides Detailed implementations in the references/ directory: Guide Contents [Stripe Integration with Python/Flask](references/stripe integration with pythonflask.md) Stripe Integration with Python/Flask [Node.js/Express Stripe Integration](references/nodejsexpress stripe integration.md) Node.js/Express Stripe Integration [PayPal Integration](references/paypal integration.md) PayPal Integration [Subscription Management](references/subscription management.md) Subscription Management Best Practices ✅ DO Use official payment SDK libraries Verify webhook signatures Store minimal payment information Never store full credit card numbers Use HTTPS for all payment routes Implement proper error handling Test with sandbox environments Handle payment failures gracefully Implement PCI compliance Log all payment transactions Use idempotency keys Implement retry logic ❌ DON'T Handle raw card data Store sensitive payment information Log sensitive details Trust client side validation only Ignore webhook events Hardcode API keys Use test keys in production Skip SSL/TLS verification Forget to validate amounts Store payment tokens without encryption

payment-gateway-integration