Clojurians Log v2

Hi everyone, I'm having some difficulty understanding how the path argument of domino.core/transact works with nested paths. Given a model of [[:patient [:first-name {:id :fname}]]] I tried (swap! ctx domino.core/transact [[[:patient :first-name] "Susan"]]) But I get the error, "key must be integer" Can I only transact based on indices?

(v 3.3)