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> Bad example. Google docs doesn’t use CRDTs but uses OT instead. CRDTs may handle your scenario just fine depending on how they decide to handle this scenario.

The CRDT may pick one or the other replacement word, but who is to say that either choice is correct? Perhaps including both words is correct.

> Then there’s not even a merge conflict...

Agree, this is what CRDTs are all about.

> ...to really worry about.

I think it is important to make clear that CRDTs do not "solve" the merging problem, they merely make it possible to solve in a deterministic way across replicas.

Often, CRDTs do not capture higher level schema invariants, and so a "conflict free" CRDT merge can produce an invalid state for a particular application.

There is also the example above, where at the application level, one particular merge outcome may be preferred over another.

So, it isn't as simple as having nothing to worry about. When using CRDTs, often, there are some pretty subtle things that must be worried about. :-)



> The CRDT may pick one or the other replacement word, but who is to say that either choice is correct?

You, as the application developer.

> I think it is important to make clear that CRDTs do not "solve" the merging problem

They literally do, in the context in which they are defined. Which is about data consistency, not semantic correctness.

> Often, CRDTs do not capture higher level schema invariants,

CRDTs never capture higher level schema invariants. Just like TCP doesn't enforce HTTP session authentication. Orthogonal concerns.


Yup 100% agreed.




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