I don't like Clojure (any more), but one nice thing about it is that is includes the Clojure implementation itself as regular versioned dependency on a project-

I don't like Clojure (any more), but one nice thing about it is that is includes the Clojure implementation itself as regular versioned dependency on a project-by-project base (thanks to the transparent usage of Maven by the leiningen build tool). Once you tried this, everything else feels like a cludge; there's simply no reason the language version should be managed by some obscure mechanism instead of being a regular dependency!