Shopify AI Toolkit for upgrading extensions to Polaris web components
Shopify developer change
MerchantDiff detected this entry in Shopify's official developer changelog on June 11, 2026.
This Shopify update is categorized as Action Required, Tools, Update.
What changed
The Shopify AI Toolkit now supports upgrading checkout and customer account UI extensions to new API versions, including the migration to Polaris web components. Use the AI Toolkit with your preferred AI coding agent to skip repetitive manual work and speed up the heavy lifting. Your agent will leverage the Shopify AI Toolkit, paired with our enhanced developer documentation, to go through the required migration steps such as handling React to Preact conversion, mapping and replacing legacy components with Polaris web components, and updating extension APIs. Extensions built with Polaris web components render significantly faster than legacy React extensions, ensuring optimal loading time and extension performance. Required for future app updates after October 1, 2026 Shopify CLI blocks apps from being updated if any of their extensions are on an API version that is more than 1 year old.
Who is affected
Shopify app developers using the API or platform feature named in this update should review the official change.
What action may be needed
Review the official Shopify entry and test the affected integration. Apply any required code or configuration changes before deploying.
Use the official Shopify entry below as the source of truth for technical implementation details, affected APIs, migration instructions and deadlines.
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