Configure Stripe Checkout tracking for back-attribution

Why this matters

If you sell via Stripe Checkout (or Payment Links buy.stripe.com), your visitors pay before submitting a lead form. Without configuration, Metrikia cannot link the anonymous touchpoints (5 Meta ads viewed over 3 days for example) to the lead created at payment time.

The mechanism relies on the Stripe client_reference_id parameter. The Metrikia pixel auto-injects the visitor's mtk_vid into it. When Stripe completes the checkout, the server webhook reads this client_reference_id and back-attributes every anonymous touchpoint of the visitor to the newly created lead.

Prerequisites

• Metrikia pixel v2.0+ deployed on all your public pages (back-attribution does not work on visitors who never saw the pixel).
• Stripe webhook configured on the Metrikia side (Integrations settings).

Method 1: Direct Stripe link (recommended, zero config)

If your checkout button is an <a> pointing to https://checkout.stripe.com/... or https://buy.stripe.com/..., you have nothing to do. The Metrikia pixel auto-detects these URLs and injects client_reference_id.

Verification:

1. Open your payment page in a browser.
2. Dev console (F12) → "Elements" tab.
3. Inspect the payment button.
4. You should see client_reference_id=<long-hex> in the href.

If the parameter does not appear, it means:

• The pixel is not loaded on this page (check <script src="metrikia-pixel.js"> in the HTML).
• The button is added dynamically after page load and the MutationObserver has not had time to tag it: manually call window.mtk('stripeify') after your render.

Method 2: Custom button with data-checkout

If you use an <a data-checkout> or a non-Stripe button that later redirects to Stripe via JavaScript, add the data-checkout attribute:

<a data-checkout href="https://your-app.com/start-checkout">Buy</a>

The pixel will inject client_reference_id on every link marked data-checkout.

If the Stripe redirect happens server-side, you must forward the mtk_vid to your backend and pass it as client_reference_id when creating the Stripe session:

// Read mtk_vid from the frontend
const mtkVid = window.mtk('getVisitorId');
fetch('/start-checkout', {
  method: 'POST',
  body: JSON.stringify({ mtkVid }),
});

// Backend (PHP example)
$session = \Stripe\Checkout\Session::create([
    'client_reference_id' => $request->mtkVid,
    // ... other params
]);

Verify back-attribution works

1. Open your site in a private window (clean cookie).
2. Navigate 2-3 pages.
3. Click a test payment button.
4. Complete checkout in Stripe test mode.
5. Go to /app/leads → open the created lead → "Journey" tab.

You should see your 2-3 anonymous touchpoints linked to the lead, with a "back-attributed" mention.

Common issues

• "client_reference_id appears in the URL but the webhook receives null": check your Stripe integration does not reset parameters. On Stripe Payment Links the parameter is preserved. On a server-created session, you must pass it explicitly.
• "The visitor has an mtk_vid but no touchpoint appears before checkout": the pixel was probably not loaded on ad pages. Check the tag is deployed everywhere, not just on the payment page.
• "I changed domains between the pixel and Stripe": this is normal, client_reference_id crosses the domain. The mtk_vid cookie stays on your site, client_reference_id travels as a query string to Stripe then returns in the webhook.