Set up WhopCart on Shopify

1. Create your Shopify app

Go to dev.shopify.com → Apps → Create app. Give it a name (for example “Checkout”).
In the app version, set Admin API access scopes: read_products, write_orders (read_orders optional). Release the version.
Click “Install app” and choose your store.
Copy the Client ID and Client secret from the app's Overview → Credentials card.
Alternative: in a legacy custom app (Shopify admin → Settings → Apps → Develop apps) copy the Admin API access token that starts with shpat_.

In WhopCart → Connections → Shopify, enter your store domain (your-store.myshopify.com).
Choose “Client ID + Secret” or “Admin token”, paste the values and click Verify & save. We call your store and show its name when it works.

In Whop, open your business dashboard → Developer. Create a Company API key with permission to create checkout configurations and read payments.
Copy your Company ID (starts with biz_).
In WhopCart → Connections → Whop paste both and click Verify & save.

Copy the Webhook URL shown under the Whop card.
In Whop → Developer → Webhooks, add it and select the payment.succeeded event.
Copy the webhook secret Whop shows, paste it into the Webhook secret field and save again. Paid orders now appear in Shopify automatically.

Shopify admin → Online Store → Themes → … → Edit code → layout/theme.liquid.
Paste the script line from Connections → “Install on your store” right before </body> and save.
The script catches the cart “Check out” button, links to /checkout, the cart drawer button and the “Buy it now” button. It reads the cart and opens your checkout.
Custom theme button? Add the attribute data-crisp-checkout to any checkout button, or data-crisp-buynow to a wrapper of a buy-now button.

Open Checkout editor. Change store name, logo, button color and texts.
Turn blocks on or off, move them up and down, delete them, or add custom text, trust badges, an announcement bar and footer links. Click Save.
Contact and Payment are always kept because the checkout needs them.

Add a product to your cart and press Check out. You should land on your checkout with the same items.
Fill in contact and address, press Continue to payment and the Whop payment form appears with all methods enabled in your Whop account.
After paying, check the Orders page here and the Orders page in Shopify.

Shopify verify fails with 401/403: re-check the secret and that the app is installed on this exact store.
Order status “paid_sync_failed”: the app is missing write_orders, or a product was deleted.
Buttons still go to Shopify checkout: make sure the script is in theme.liquid and not blocked by another app.