How is the story around Clara and out-of-order processing? Like if I were processing real time events that had a chance of coming out of order, this would be a natural fit for a rules engine right?

Truth maintenance in clara should honor any order of execution. if the rules are satisfied it should not matter the order of the facts

Is a rules engine the correct fit for the use case is a little more of a muddy answer.... and it probably comes down to "it depends". It depends on the use-case you are trying to solve with reasoning about the series of events. If its reasonably sized then a rules engine might be considered overkill, but if you are trying to tie a lot of disparate reasoning together in a logical manner, then a rules engine might be correct.

We’re building a graph database with real time events sourced from multiple systems... it’s not overkill to consider a rules engine in my opinion

Maybe I should read up on truth maintenance systems... that’s basically what we’ve been building, without knowing it

If I understand correctly