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GigaCommerce

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.

Get your Readiness Score

100 points across catalog, schema, product pages and checkout, with the three fixes that matter most.