SaaS Payment Patterns

Provider-agnostic payment patterns for subscription-based applications. Works with Stripe, Paddle, LemonSqueezy, or any billing provider.

Payment Provider Abstraction Layer

// Abstract away the provider — swap Stripe for Paddle without touching business logic

interface PaymentProvider {
  createCustomer(data: CreateCustomerDto): Promise<Customer>
  createSubscription(data: CreateSubscriptionDto): Promise<Subscription>
  cancelSubscription(subscriptionId: string, immediate?: boolean): Promise<void>
  createCheckoutSession(data: CheckoutDto): Promise<{ url: string }>
  issueRefund(paymentId: string, amountCents?: number): Promise<Refund>
  getInvoice(invoiceId: string): Promise<Invoice>
  verifyWebhookSignature(payload: string, signature: string): boolean
}