Lemon Squeezy revenue attribution

1Checkout links: set the button link back to your site

In Lemon Squeezy, open each product and set the Button Link of both the Confirmation Modal and the Email Receipt to a page on your site that has the Chartsy tag, ending in ?order_id=[order_id]&order_identifier=[order_identifier]:

https://yoursite.com/thank-you?order_id=[order_id]&order_identifier=[order_identifier]

Lemon Squeezy fills both in. When the buyer lands, Chartsy looks up the order with your connected store and credits it to the visit that brought them. Keep order_identifier: order ids are sequential, and the identifier proves the link came from the purchase. See success-page matching for the details.

2Creating checkouts from your server: add custom data

Lemon Squeezy sends checkout custom data to Chartsy's webhook, so put the visitor's chartsy_visitor_id cookie there:

import { createCheckout } from '@lemonsqueezy/lemonsqueezy.js';

await createCheckout(storeId, variantId, {
  // ...your existing options
  checkoutData: { custom: { chartsy_visitor_id: req.cookies.chartsy_visitor_id || '' } },
});

Custom data only reaches Chartsy through the webhook, so it works for purchases made after you connected the store.

Email matching and GDPR mode

• Without either method, Lemon Squeezy buyers are still matched by email to people who signed up. Calling window.chartsy.identify({ email }) on your post-purchase page works too.
• With GDPR mode on for the Lemon Squeezy source, no emails are stored, so email matching stops - the two methods above keep working.