Business Key feature in Camunda 8

I currently evaluate to move our Camunda usage from Camunda 7 to Camunda 8.

The current implementation with Camunda 7 is mainly based on the business key feature. This is the linkage between the Camunda scope and our application scope. We use that key to search for follow up tasks for the current user and also as search criteria to return the process state. On each delegate we use the key for our business operations.

I have not seen something similar on Camunda 8. Also a workaround with process variable will not work, because the current APIs does not support such query option.

How should this work on Camunda 8? The explanation in following post does not help.

Are you plan to add that feature?

BR Bernd