I would really love some ready-to-use ecommerce modules, it would really give Wappler superpowers.
A way that you can use it right now it is to store the cart items in a session, like Teodor described here: Adding eCommerce to a Wappler Site
By using Shopify for instance you can then generate a checkout with the products in cart, quite easily in a URL (no API needed) by using this format: http://yourstore.com/cart/#{variant_id}:#{quantity}
(more info about that here: https://help.shopify.com/en/themes/customization/cart/use-permalinks-to-preload-cart)
But a module would be even better. In general, modules like that would really make things easy for non-developers to build great websites. Templates, modules, usable showcase websites, etc. Hope they will implement something like that in the future.