Developer friendly

Build with the FastStar SDK and API

A clean, white-label integration. Open the hosted checkout with a single call, react to events on the front end, and reconcile reliably with webhooks. You integrate only with FastStar — never directly with Stripe.

JavaScript SDK

JavaScript SDK

Include FastStar.js and open the hosted checkout as a popup or redirect with one call. The SDK has zero dependencies and emits events you can subscribe to, such as checkout.success and checkout.error.

View JS SDK →
// Include FastStar.js, then open the checkout in one line
// <script src="https://cashier.faststarpay.com/sdk/v1/faststar.min.js">
FastStar.checkout.open({
  url: session.url,
})

// Listen for the payment result
FastStar.on('checkout.success', (data) => {
  console.log('Paid', data.payment_intent_id)
})

Flutter SDK

For native mobile apps, the Flutter SDK provides a WebView-based checkout component with unified callbacks, so you get the same hosted, white-label experience inside your iOS and Android apps.

Flutter SDK docs →

Webhooks

Subscribe to event-driven webhooks to keep your systems in sync. Key events include payment.succeeded, subscription.created, subscription.renewed, subscription.canceled, payout.paid and dispute.created. Each webhook is signed so you can verify authenticity before processing.

Webhooks docs →

REST API overview

The REST API covers the full lifecycle: create and manage payments and payment links, subscriptions and plans, customers, refunds and payouts. Authenticate with your API key, send JSON, and receive predictable, well-structured responses.

API reference →

White-label by design

Everything your customers see is under your brand, powered by FastStar. You never integrate with Stripe directly and never need a Stripe account — any third-party processors live entirely on our servers, behind our API.

Start building today

Create a free account, integrate in minutes, and leave global payments and tax compliance to FastStar.