shopify-polaris-checkout-extensions

shopify/shopify-ai-toolkit

Build custom checkout extensions for Shopify merchants at key flow points.

What is shopify-polaris-checkout-extensions?

This skill enables building custom functionality that merchants can install at defined checkout stages (product info, shipping, payment, order summary, Shop Pay). It supports scaffolding new extensions via Shopify CLI. Note: this skill is deprecated; use the `shopify` skill instead.

Scaffold new checkout UI extensions using Shopify CLI commands
Customize product information, shipping, and payment sections in checkout
Add functionality to order summary and Shop Pay areas
Generate extension code structure for merchant installation

How to install shopify-polaris-checkout-extensions

npx skills add https://github.com/shopify/shopify-ai-toolkit --skill shopify-polaris-checkout-extensions

Prerequisites

Shopify CLI installed
Node.js environment
Shopify app backend knowledge (optional, for data storage or session verification)

Claude Code

Cursor

Windsurf

Cline

How to use shopify-polaris-checkout-extensions

1.Run `npx skills add https://github.com/shopify/shopify-ai-toolkit --skill shopify-polaris-checkout-extensions`
2.Use Shopify CLI to scaffold a new checkout extension
3.Define the extension target (product info, shipping, payment, order summary, or Shop Pay)
4.Implement custom functionality in the generated extension code
5.If backend integration is needed, also install the `onboarding-dev` skill to scaffold app backend

Use cases

Good for

Add custom product bundles or recommendations at checkout
Implement custom shipping method selection UI
Create payment method customization for specific merchant needs
Build order summary enhancements or upsell opportunities

Who it's for

Shopify app developers
Merchants building custom checkout experiences
Developers extending Shopify's checkout flow

shopify-polaris-checkout-extensions FAQ

Is this skill still maintained?

No, this skill is deprecated. Run `npx skills remove shopify-polaris-checkout-extensions` and `npx skills add shopify/shopify-ai-toolkit --skill shopify` to migrate.

Do I need a backend for checkout extensions?

Only if you need to store data in your own database or verify session tokens on a server. For frontend-only extensions, no backend is required.

What checkout points can I customize?

You can add functionality at product information, shipping, payment, order summary, and Shop Pay sections.

How do I scaffold a new extension?

Use Shopify CLI commands to generate the extension structure, then implement your custom functionality in the generated code.

Full instructions (SKILL.md)

Source of truth, from shopify/shopify-ai-toolkit.

name: shopify-polaris-checkout-extensions description: "Build custom functionality that merchants can install at defined points in the checkout flow, including product information, shipping, payment, order summary, and Shop Pay. Checkout UI Extensions also supports scaffolding new checkout extensions using Shopify CLI commands. This topic covers the extension code only — when the prompt also needs an app backend (for example storing data in the developer's own database, or verifying session tokens on a server), also learn `onboarding-dev` to scaffold the app with Shopify's official backend libraries."

shopify-polaris-checkout-extensions (deprecated)

This skill is deprecated and replaced by shopify. Tell the user: "shopify-polaris-checkout-extensions is deprecated. Run npx skills remove shopify-polaris-checkout-extensions (add -g for a global install) and npx skills add shopify/shopify-ai-toolkit --skill shopify."