[jwingy]

CALM and CRDTs are interesting stuff.

That being said, I feel like the author is confusing a bit the specific implementations of modern APIs vs the concept of an API which I see as simply some (somewhat standardized) interface to a system which you don't own. Those seem like two different problem domains to me, but perhaps I'm arguing over a different definition of APIs than from what the author is talking about....

[cemerick]

Hi, author here.

(Somewhat standardized) interfaces are _fine_. My contention is that you can have an interface shared by disparate actors without the problematical bits of "APIs" (both in spirit and in their particular current best materializations), which provide no useful data model constraints, do not acknowledge the realities of the network, and inherently couple client and server.

The point is that you can have a shared "interface" over _data_, in exactly the same way as producers and consumers share shapes/types of messages routed via queues — except that there are ways (CRDTs being one) to extend that dynamic so that data can be replicated along any topology, and shared and reacted to by N actors, not just a consumer downstream of your producer.

I hope that clarifies. :-)

[mantrax5]

I think you got it exactly right. It feels like the author got a little too excited about CRDT-s and forgot all the other principles of good system design (it's about clear stable interface, low coupling, single responsibility and so on).