Integrating regular Shopify store with a custom Storefront

Topic summary

A developer is attempting to add custom fields to the checkout shipping address form for a Shopify Plus store. They initially asked about creating a custom checkout page using the Storefront API while keeping the main store for browsing and cart management.

Recommended Solution:

  • Use Checkout UI Extensions instead of Storefront API (which isn’t designed for checkout customization)
  • Alternative: Shopify Functions to extend backend logic

Key Concerns Raised:

  • The Checkout UI Extensions documentation shows “unstable” status in the version dropdown
  • Advised to wait for stable API release (2023-10, available October 1, 2023) before production deployment
  • A relevant tutorial for custom checkout fields was shared as reference

Technical Clarification Needed:
The developer is confused about implementation details:

  • Whether checkout UI extensions require hosting as a custom server-side app
  • Where to place React components from examples (their team typically uses Java backend and Vue.js)
  • How the app’s install URL functions in this context

Status: Discussion remains open with technical implementation questions unanswered.

Summarized with AI on November 19. AI used: claude-sonnet-4-5-20250929.

Sure - you can ask more questions here. Also, I’ve digged into this a bit more and this tutorial that uses checkout UI extensions looks close to what you’re trying to achieve. You could try this out and augment it for your own purposes.