clojure.core loads clojure.java.io to define slurp and spit. clojure.java.io loads clojure.string, solely for a single call to replace. This slows down Clojure core startup for no reason.
Approach: Replace clojure.string/replace call with a Java interop call to .replace. This saves about 18 ms during Clojure core startup.
Patch: clj-1895.patch