I thought so too, at first, but now I'm really down on it. Ecto Changesets work fine for flat data, but when you have to deal with nested data, it becomes a nightmare, because you have to use these special functions to read and update the data. Doing that in a nested context just gets really clunky, especially coming from Clojure, where I would just do something trivial, like

    (assoc-in changeset [:children 1 :title] "New title")