POS UI Extension - size limit and libraries

Shopify Apps

Topic summary

A developer is seeking clarification on two technical aspects of Shopify’s POS UI Extensions:

File Size Limits:

  • Theme app extensions have documented file size limits
  • Unable to locate similar documentation for POS UI Extensions
  • Requesting confirmation whether size limits exist and what they are

Recommended Libraries:

  • Asking for Shopify’s suggested libraries for:
    • Internationalization (i18n)
    • State management
    • React usage within POS UI Extensions

Status: Question remains unanswered; developer awaiting guidance on best practices and technical constraints for POS UI Extension development.

Summarized with AI on November 12. AI used: claude-sonnet-4-5-20250929.
1

Do we know the file size limits for POS UI Extension? Theme app extension has one, can’t find the same thing for POS UI Extension.

Also is there any suggested libraries that Shopify recommend to do i18n and state management in POS UI Extension React apps?