Have you ever wanted to link directly to the Shopify checkout with a specific cart already loaded? Cart Permalinks allow you to do this easily.
This is what a cart permalink looks like:
Visiting a cart permalink takes you directly to the first page of the checkout with the specified variant ids and quantities. Any cart that is currently in the session will be completely untouched and ignored.
The format of the url is:
Notes, cart attributes, and tracking parameters can be added as query parameters like usual. If customer accounts is enabled, and the user is not logged in, they will see the login page before reaching the checkout.
This feature is useful for things like putting "Buy it now" buttons on blogs, sending reorder links, and selling comic prints (like in the above image from Penny Arcade).