Shopify & eCommerce
Checkout Extensibility (Shopify)
Quick definition
Shopify Plus's modern checkout customization model using web pixels, UI extensions, and Functions, replacing the deprecated checkout.liquid.
What it actually means
Shopify deprecated checkout.liquid customization for Plus stores in 2024. Checkout Extensibility is the replacement: a component-based, upgrade-safe model using checkout UI extensions, React-like components rendered in checkout, web pixels for event tracking, and Shopify Functions for custom backend logic on discounts, shipping, and payments. Brands with heavy legacy checkout customization, custom fields, conditional shipping, payment logic, need to rebuild that work during migration.
Related terms
Shopify Plus
Shopify's enterprise plan. Public starting price is $2,300 USD/mo as of 10 November 2026. Adds full checkout customization, unlimited B2B catalogs, expansion stores, and higher API limits versus standard Shopify.
Shopify Functions
Server-side WebAssembly modules that run custom logic at checkout: discounts, shipping rules, payment customizations, and validation.