Clojurians Log v2

So I'm running this example from the om next quickstart https://github.com/omcljs/om/wiki/Quick-Start-%28om.next%29#naive-design however I keep getting the error Error: Assert failed: (reconciler? reconciler)

Seems the reconciler passed to om/add-root! doesn't seem to be a valid one

I can't quite see why this is so. I even copied and posted that same example into a cljs file and same error