@spieden this is a more flexible way to approach that:

(def MAP-NODES
  (recursive-path [] p
    (cond-path
      map? (stay-then-continue MAP-VALS p)
      coll? [ALL p]
      )))

(setval [MAP-NODES MAP-VALS nil?] NONE {:foo {:baz nil} :bar :bam})

MAP-NODES could then be used for other things besides nil filtering

indeed! thanks