Scala does have more support for OO than Clojure with traits, case classes and pattern matching, and generics but Clojure does have enough support for OO for basic service creation. See https://github.com/gengstrand/clojure-news-feed as an example where Clojure's defprotocol, defrecord, defmulti, and defmethod are used to implement a basic CRUD style RESTful API for 4 entities in about 300 lines of code.