The delegateExpression works indeed as you describe. If the delegateExpression doesn’t resolve, it means Flowable can’t access the Spring applicationContext.
Can you share your setup? Is this Spring Boot or regular Spring.?The SpringApplication seems to indicate it’s Spring Boot. But the fact you’re setting up a transaction manager manually seems to point at regular Spring?
More specifically, how are you setting up the ProcessEngineConfiguration? Using Spring it needs to be SpringProcessEngineConfiguration, which does the logic to get access to the applicationContext. Assuming that this is not Spring Boot of course, where this will happen automatically.
No need to ping me. We try to look at all forum questions regularly (but as everyone here, we’ve got work priorities, too).