No, it’s not anywhere near ready yet. I’ve stopped while waiting for the rule UID stuff to get resolved for now, but I still have things to make. I must make a new REST endpoint to “check serializability” (not sure what I should call it) for rules, because the UI must call that before trying to serialize the rules. I must also figure out how to give feedback for the check in a practical way so that it can be shown in a meaningful way in the UI.
My plan was to soon start implementation in the UI, and then do the rest “in parallel”. That way I will find out what is missing in core or that need to be changed to make the UI work like it should. But, I still have some things to do in core before there’s any point starting with the UI work, especially this “check endpoint”. I haven’t completely implemented everything that’s implemented for Things and Items yet either, but I don’t think there is much missing.