It seems like you’re having lots of problems with the transformation functions. I wasn’t expecting them to be a bottleneck. Did you investigate CRDTs (especially delta-CRDTs)? You’d have (probably much) higher memory requirements, but “transformations” would be quicker. You’d have problems rendering the underlying CRDT into JSON, but that work can be offloaded to the clients (the server might not even need to render anything).
