Website Pay Widget - Integration Guide

Overview

SlicePay uses a hosted checkout pattern (similar to Stripe Checkout redirect). Your website passes the cart total, order reference, and optional description to pay.slicechain.io. The customer completes payment in a secure hosted flow; funds settle to your linked merchant wallet in USDC.

• Checkout host: https://pay.slicechain.io
• Embed script: https://pay.slicechain.io/embed.js
• Gateway API: https://api.slicechain.io/api/gateway
• No iframe required - popup or full-page redirect

Before you start

• A SlicePay business account with a linked Solana wallet (Business dashboard → Settings)
• Your merchant ID (MongoDB business `_id` from the dashboard or API)
• HTTPS on your production store (recommended for checkout popups)
• Optional: `apiKey` from Business settings for server-side invoice creation

Option A - Embed script (minimal, no backend)

Add one script tag to your checkout or cart page. Replace `YOUR_MERCHANT_ID` with your business ID. Static amounts work for fixed-price products; use JavaScript for dynamic cart totals (see below).

<script src="https://pay.slicechain.io/embed.js"
  data-merchant-id="YOUR_MERCHANT_ID"
  data-amount="49.99"
  data-order-id="ORD-12345"
  data-description="2x Large Pepperoni"
  data-redirect="https://yourstore.com/thanks"
  data-popup="true"></script>

Dynamic amount from your checkout page

Read the cart total from your page state and open hosted checkout when the customer clicks Pay with Crypto:

document.getElementById('pay-crypto').onclick = () => {
  const amount = document.getElementById('cart-total').value;
  const orderId = 'ORD-' + Date.now();
  const url = new URL('https://pay.slicechain.io/');
  url.searchParams.set('merchantId', 'YOUR_MERCHANT_ID');
  url.searchParams.set('amount', amount);
  url.searchParams.set('orderId', orderId);
  url.searchParams.set('description', 'Order from My Store');
  url.searchParams.set('redirect', 'https://yourstore.com/thanks?order=' + orderId);
  window.open(url.toString(), 'slicepay', 'width=480,height=820');
};

Option B - Direct hosted URL

Link or redirect customers to:

https://pay.slicechain.io/?merchantId=YOUR_MERCHANT_ID&amount=49.99&orderId=ORD-12345&description=Order+note&redirect=https://yourstore.com/thanks

Option C - Server-side invoice (recommended for production)

Create the invoice on your server so the amount cannot be tampered with in the browser. Then redirect the customer to the returned `invoiceId`.

// POST https://api.slicechain.io/api/gateway/create-invoice
{
  "merchantId": "YOUR_MERCHANT_ID",
  "amountUsd": 49.99,
  "orderId": "ORD-12345",
  "description": "Cart checkout",
  "redirectUrl": "https://yourstore.com/thanks",
  "apiKey": "optional-business-api-key"
}

// Redirect customer to:
// https://pay.slicechain.io/?invoiceId=PUBLIC_INVOICE_ID

Parameters reference

• merchantId - required; your SlicePay business ID
• amount / amountUsd - checkout total in USD (min $0.01)
• orderId - your order reference (1–128 characters)
• description - optional note shown on receipt (max 500 characters)
• redirect / redirectUrl - where the customer returns after paying
• invoiceId - load an existing server-created invoice instead of URL params

Payment confirmation on your site

After a successful payment, SlicePay checkout sends a postMessage to the page that opened the popup:

• Return URL includes: ?orderId=…&status=paid&tx=…&invoiceId=…
• Poll GET /api/gateway/payment-status/:invoiceId from your server for authoritative status
• Invoices expire after 30 minutes

window.addEventListener('message', (event) => {
  if (event.data?.type !== 'slicepay:paid') return;
  // Validate event.origin in production (https://pay.slicechain.io)
  console.log(event.data.orderId, event.data.txSignature, event.data.invoiceId);
});

Testing

• Mock merchant store: https://pay.slicechain.io/test-embed.html
• Business dashboard → Online Payment Gateway → Test SlicePay checkout
• Automated smoke test (self-hosted): node scripts/gateway-smoke-test.js in the platform repo
• Use a mainnet USDC wallet for a live end-to-end payment test

Support

Questions about integration? Email slicepay@slicechain.io or open the business dashboard for gateway test tools.