Shopify
Checkout extensibility
Definition
Shopify's framework for customizing checkout using UI extensions and checkout functions instead of editing checkout.liquid directly. It lets merchants add or modify specific, sanctioned surfaces of checkout — banners, fields, upsells, delivery options — while Shopify continues to own and update the core checkout flow underneath.
Defined in Checkout Extensibility: What to Customize, What to Leave.
Where Checkout extensibility comes up
The guides that put this term to work, rather than just defining it.
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