Once we figured out the "CRDT trick", i.e. simulating file changes as CRDT update operations, it was surprisingly quick to implement. If you look at our repo [1], you will see that the code is fairly straightforward and succinct. But this is very much thanks to the excellent work of Kevin Jahns on Yjs [2], which has made it a breeze to work with CRDTs in an efficient way!
[1] https://github.com/motifland/yfs [2] https://yjs.dev/