(def ffs [{:type :folder, :name "sub1", :children [{:type :file, :name "datomic-data.edn"}]}
          {:type :folder, :name "sub2", :children [{:type :file, :name "foo (1).csv"}
                                                 {:type :folder, :name "sub21", :children [{:type :file, :name "lein-env"}]}]}])

(def tree-path ["sub2" "sub21"])