"state managed safely" is from the article, not me...... I'd guess it means consistent state. Yes, cluster sharding is layer to solve this, but you end up with some new problems to do with sharding. Also it seems the programming model doesn't seem super straight forward. It needs a db by default, but can use distributed data to do it also. but I'm not sure, I haven't tried it yet. It's all beta/experimental so no idea how battle hardened it is? And how would it all compare to using something like a clustered redis system to store state?