Changing a custom attribute from email click

Hello Alex You will have to create a middleware to do this.

Your specified link would be middleware link something like

https://abc.com/middleware?id=external_id (external_id is passed to identify which profile to update in Braze)

now this middleware when accessed will perform 2 operations

1. Redirect user to the actual URL
2. Do an API call to update custom attribute in Braze based on the external_id received in URL

Hey Alex, you can use Braze's Link aliasing feature to trigger a custom webhook to update a user's custom attribute.

You can view the Braze learning course here: https://learning.braze.com/link-aliasing
And documentation here: https://www.braze.com/docs/user_guide/message_building_by_channel/email/templates/link_aliasing?tab=html%20editor#creating-a-link-alias 

I created a video for a similar use case; this should work for custom attributes as well!

https://www.youtube.com/watch?v=DYWrgB2Qieg