Automated testing for Shopify UI extensions with @shopify/ui-extensions-tester
Shopify developer change
MerchantDiff detected this entry in Shopify's official developer changelog on April 13, 2026.
This Shopify update is categorized as API, New, Admin Extensions, Checkout UI, Customer Accounts, POS Extensions, 2026-04.
What changed
As of API version 2026-04, Shopify provides an official testing library for UI extensions. @shopify/ui-extensions-tester lets you write unit tests for extensions on any surface — Checkout, Admin, Customer Accounts, and POS — without a running Shopify host. What it does The library provides strongly typed mocks of the extension API, so you can render extensions in isolation, simulate user interactions, and verify behaviour against public APIs with full type safety. Key capabilities Render and query: Render your extension in a standard DOM environment and query the output using standard testing patterns. Type-safe mocks: The mocked shopify global uses the same types as the real API, catching incorrect API usage at test time.
Who is affected
Developers maintaining Shopify POS apps or POS UI extensions should review this change.
What action may be needed
Review whether the new capability is relevant to your app. If you plan to use it, test the affected API or workflow before adopting it in production.
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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