[staticassertion]

Hm, ok, yeah. So I guess I can see what you mean. I've never had a use case where I felt comfortable relying on any kind of message ordering, and always rely on my application level logic to handle that, or ensure the system is resilient despite ordering (ie: commutative operations only).

To me, it seemed at odds with the parallelism of a partition, but I suppose in this case you'd be partitioning on some sort of semantic key vs, say, a hash.

Thanks for bearing with me on that, this was just an unfamiliar idea for me.