I usually write a macro (defn-typed) that generates pre- and post-conditions (contracts, essentially) for crucial APIs when I'm working in Clojure. It's not as

I usually write a macro (defn-typed) that generates pre- and post-conditions (contracts, essentially) for crucial APIs when I'm working in Clojure. It's not as good as static analysis at catching all type errors-- if that's what you need, I wouldn't recommend any dynamic language-- but it does mean that most type errors will be caught in unit testing, with minimal recurring work.