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Comment by jiofih | Hacker News Reader

But the article is arguing in favor of OT, not CRDT. A couple examples of those edge cases would go a long way, the one given is not very helpful to make a point.

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What's wrong with the one given? If my cursor moves because some other user makes some other text bold, that doesn't sound like a desirable experience?

Because it doesn’t highlight a particularly relevant deficiency of the CRDT protocol. Preserving cursor position is not hard in that case. The post even mentions stronger downsides of OT, the example does not support the conclusion. Why is OT better?

Huh, the article gave me the impression that preserving the position was a crucial problem there.

As for the last question, I think the later posts will get to that.

Preserving the position of the cursor is a crucial feature for collab editors. However, he doesnt go into detail explaining why CRDTs make this feature impossible. Sure the CRDT route splits the text, but I fail to see why that makes cursor pos preservation impossible?

It's not impossible, particularly in cases where the model is fairly flat.

In complex models it is symptomatic of a larger issue with complexity in CRDTs; the post was already quite long and I didn't want to repeat any more of the research I'd linked to.

You mention that example as a turning point for choosing OT, confirming your research. But to an outsider it is not particularly convincing. Especially since you’d expect a CRDT implementation to use the rope/tombstone structure, applying the transform to that sequence of characters and not actually have to split a text node, which looks like a limitation of this particular implementation, or tight coupling between the data model and the DOM.

The post is a good introduction to OT and CRDT, but is very light on actual trade-offs and seems to end with a gut-feeling conclusion, when the title promised “trade-offs between”.

It's hard to offer more detail than that in a blog post. I'm not going to repeat the research papers or write one of my own. The post is already so long and complex, covering so many surface details, I couldn't reasonably push it any further.

I’d suggest skipping right to the meat of the subject (pros/cons in this case), assuming some previous knowledge, if that’s what the article proposes to share, and simply point readers to learning resources; it’s not possible to start from scratch on every topic. The deeper the subject, the more glaring this problem becomes.

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