> Last-Writer-Wins is a conflict resolution strategy that can be used by any kind of data type that needs conflicts resolved, CRDTs included. Unfortunately it's not a very good one: even if you use vector clocks instead of wall clocks, it doesn't give you much stronger guarantees than determinism. That is, given two concurrent writes, the winner is essentially arbitrary. LWW is a merge strategy of last resort; if that's the only thing your CRDT system offers, I'm not sure it's really fair to call it a CRDT system.
Can't reply to the comment below, so replying here.
I believe what markhenderson was trying to say is that in OrbitDB, the default merge strategy for concurrent operations is LWW.
The comment above is conflating a lot of things here. 1) determinism is exactly the guarantee one needs for CRDTs, and I'd argue generally is a good thing in distributed system but 2) adding vector clocks (OrbitDB uses Lamport clocks, or Merkle Clocks [1], by default), nor wall clocks, have nothing to do with determinism and in fact there's a good reason to not use vector clocks by default: they grow unbounded in a system where users (=IDs) are not known. In my experience, LWW is a good baseline merge strategy.
I don't think it's at all correct to say that "the winner is essentially arbitrary" because it's not. The "last" in LWW can be determined based on any number of facts. For example "in case of concurrent operations, always take the one that is written by the ID of the user's mobile device", or "in case of concurrent operations, always take the one that says should come first". It'd be more correct say "the winner is based on the logical time ordering function, which may not be chronological, real world time order".
As for the last comment, I'm pretty sure it's a CRDT system :) Want to elaborate your reasoning why you think it's not a CRDT?
[1] "Merkle-CRDTs: Merkle-DAGs meet CRDTs" - https://arxiv.org/abs/2004.00107