Payment providers

Connect Lemon Squeezy

Set up Lemon Squeezy tracking, pass the click ID and verify a credited purchase.

This guide connects your customer checkout to Slice. It is separate from the payment method you add in Billing and the bank details publishers add in Payouts.

This provider connection is in beta. Complete a purchase and refund test before relying on it for a live program.

1. Before you start

Create your business, product and campaign in Slice. An owner or admin can change payment integrations.
Open Payment providers, select the correct product and choose Test mode first. Each product and mode has its own connection.
A Lemon Squeezy store with Test mode enabled for your first run.
Access to checkout creation code or the checkout link you share.

Open Payment providers in Slice

Choose one reporting path for each sale: a provider webhook connection or your own Conversions API integration. If your site already reports purchases to Slice, review it before enabling a second path; different order identifiers can produce duplicate sales.

2. Connect the provider

In Slice, open Lemon Squeezy and click Connect to prepare this product's webhook URL. Keep the panel open while you configure the provider.

In Lemon Squeezy, open Settings, then Webhooks, then add a webhook.
Paste the URL from Slice, choose your own signing secret (6 to 40 letters and numbers), and tick the events listed below.
Save, and paste the same signing secret in Slice.

Select these events. If the provider has friendly event labels, use the matching labels shown in the instructions above:

order_created
order_refunded
subscription_created
subscription_payment_success
subscription_payment_refunded

Return to Slice, paste the lemon squeezy signing secret and click Connect Lemon Squeezy. Saving the secret does not prove checkout attribution works yet.

3. Pass the publisher's click ID

On your website, load slice.js on every landing page. It stores the visitor's sclid in the slice_click_id cookie. Your backend can read that cookie when creating checkout; in the browser, window.Slice.clickId() returns the same value after the script loads.

<script src="https://takeslice.com/slice.js" async></script>

Custom checkout data, which arrives in meta.custom_data. Keep the existing checkout configuration in the example below and add the attribution field; the snippets show the integration point, not a complete checkout. Only send an ID matching clk_ followed by 32 hexadecimal characters. Omit it if no valid click is available.

await createCheckout(storeId, variantId, {
  checkoutData: { custom: { slice_click_id: clickId } },
});
// Or on a checkout link: ?checkout[custom][slice_click_id]=clk_...

Choose a signing secret of 6–40 letters or numbers and enter exactly the same value in Lemon Squeezy and Slice.
Checkout custom data arrives under meta.custom_data. It is not ordinary product metadata.
For subscription attribution, subscribe to subscription_created as well as subscription_payment_success and subscription_payment_refunded.

4. Test delivery and attribution

Follow the Slice test link, then complete a Lemon Squeezy test checkout with checkout custom data containing slice_click_id.
Check the webhook delivery log and confirm the matching conversion is attributed in Slice.
Test a one-time refund, and a subscription payment/refund if your product sells subscriptions. These use separate events.

Connected means credentials were saved. A received event means a delivery reached Slice. Only an attributed conversion proves the sale was credited to a publisher. Use a test link and matching sandbox purchase for the full check; test conversions create no money.

5. Switch to Live

Return to the same product's Payment providers page and choose Live. Create the production connection separately with the production account, endpoint and credentials. Do not reuse a test click for a live purchase. Confirm the production checkout carries attribution before sharing live publisher links.

Troubleshooting

Signature rejected: verify both copies of your chosen signing secret. Lemon Squeezy API keys and license keys are different credentials.
Missing renewals: enable all listed subscription events and check that the original subscription creation included custom data.
No delivery: inspect Settings → Webhooks and resend a failed delivery after correcting the connection.
No event in Slice: check the provider's delivery log, selected events and full HTTPS URL. Localhost cannot receive external webhooks without a public tunnel.
No credited conversion: check the click ID, selected product, test/live mode, paid amount and currency. Slice currently supports EUR, USD and GBP.
Disconnecting a webhook provider does not remove the endpoint from that provider's dashboard. Remove or disable it there too. Stripe endpoint removal is attempted automatically.

Official provider documentation

Provider instructions checked against the references below on 29 October 2026. Provider dashboards can change; the event names and attribution fields above describe what Slice currently handles.