Cart Transform Function not appearing in Checkout Rules on some stores (same app, same function)

Shopify App Store
1

Hi everyone,

I’m facing a strange issue with a Cart Transform Function, and I’m hoping someone in the community might have encountered something similar.

Context

  • I have one Shopify app that uses a Cart Transform Function.

  • The function uses expand operations, so it should not be affected by the store’s plan.

  • The same app is installed on multiple stores.

  • On most stores, the cart transform function is installed successfully and appears in Checkout Rules as expected.

  • These stores are on various Shopify plans (Basic, Shopify, Advanced, etc.), and everything works correctly.

The problem

On a few specific stores, after installing the app:

  • The Cart Transform Function does NOT appear in Checkout Rules

  • It seems like the cart function is not registered or not installed on those stores

This happens even though:

  • The app installation itself succeeds

  • The same app and the same function work correctly on other stores

What I’ve tried

  • Uninstalling the app and installing it again (to force re-registering the cart function)

  • Verifying that:

    • The app version is the same

    • The function code and deployment are exactly the same

However, the issue still persists on those specific stores.

Looking for help / suggestions

At this point, I’m running out of ideas to debug this issue and would really appreciate any help from the community.
I’m looking for guidance or possible approaches to resolve or work around the situation where a Cart Transform Function is not registered and does not appear in Checkout Rules on certain stores, despite working correctly on others.

Any insights, experiences, or suggestions would be extremely helpful.
Thanks in advance :folded_hands:

2

Have you made sure that your app is running the cartTransformCreate mutation?

1 Like
3

Thanks for the suggestion!
Yes, we are running the cartTransformCreate mutation as part of the app installation flow.
We believe it’s working correctly since the same app and code successfully register the Cart Transform Function on many other stores.
That’s why it’s confusing that it doesn’t appear in Checkout Rules on only a few specific stores.

4

Thanks for the suggestion!
Yes, we are running the cartTransformCreate mutation as part of the app installation flow.
We believe it’s working correctly since the same app and code successfully register the Cart Transform Function on many other stores.
That’s why it’s confusing that it doesn’t appear in Checkout Rules on only a few specific stores.

5

But to be absolutely certain, can you query cartTransforms on the stores its not working and ensure they exist?