[mweidner]

> We don't use any fractional indices though. Instead, our insmov tuple not only contains a parent P, but also a previous sibling guid A. Because all tree ops will eventually be applied in the global linear order as determined by the server, "sorting" is handled by just using the insmov operation.

For what it's worth, this sounds equivalent to the RGA list CRDT [1], using the server's global linear order as a logical timestamp (in place of e.g. Lamport timestamps).

[1] https://inria.hal.science/inria-00555588/

[wim]

Right but rather than working on an array it's combined with a tree operation in this case, so if someone drags a task to reorder but someone else moves it to another parent it won't cause (cycle) conflicts