Integration versus automation – where to draw the line

A common discussion when designing complex software architectures is where to define the boundary between integration and automation.

After all, there is a bit of overlap: both a business workflow and an integration route can call a number of external systems sequentially or while going through conditions (which may be represented, in both cases, as business rules).

Of course, there is not a fixed answer for every behavior. I personally prefer to avoid polluting the business automation with too many technical integrations (such as connectors for specific uncommon technologies, everything that is not a call to a web service or a message in a queue) and the integration routes with conditions that are dependent on specific business requirements (such as modeling a business process as an integration route). But other than this high-level, common-sense advice, there are a few considerations that can help in understanding...