I’ve built several apps on yjs and highly recommend it. My only complaint is that storing user data as a CRDT isn’t great for being able to inspect or query the user data server-side (or outside the application). You have to load all the user’s data into memory via the yjs library before you can work with any part of it. There are major benefits to CRDTs but I don’t think this trade-off is worth it for all projects.