Attribute revenue with LemonSqueezy Checkout API
Make sure you've connected your LemonSqueezy account first.
Pass custom with datafast_visitor_id and datafast_session_id (cookies from DataFast) when creating a checkout session:
// app/api/create-checkout/route.js
import { cookies } from 'next/headers';
export async function POST() {
const cookieStore = cookies();
// If you're using Next.js 15+, use this instead:
// const cookieStore = await cookies();
const { data, error } = await createCheckout({
storeId,
variantId,
{
productOptions: { ... },
checkoutData: {
...,
custom: {
datafast_visitor_id: cookieStore.get('datafast_visitor_id')?.value,
datafast_session_id: cookieStore.get('datafast_session_id')?.value
}
}
}
});
}
Once connected and custom data is properly passed, DataFast will automatically attribute revenue to the correct marketing channels. No webhook setup is required.
After receiving a successful payment, you should see revenue data in your dashboard (referrer, country, browser, etc.). If you don't, please contact us at marc@datafa.st.