There would be annotations in the same places as Typed Clojure, except :no-check would be replaced by type soundness-preserving runtime assertions. There would be no need for :no-check anyway; Typed Racket's base annotations are complete AFAIK.

It is a little clearer to me how this works with things like primitives, but how do you annotate a function that takes a map as input and returns a list? (defn my-keys [m] (keys m))

Edit: Just found Seqable. Looking into it now. This link helped me a lot. https://github.com/clojure/core.typed/wiki/Types

Ambrose pointed me at this link for documentation of core.typed's convenience type wrappers (Vec, Seq, List etc.): http://clojure.github.io/core.typed/#clojure.core.typed/Seq

(ns my-ns (:require [clojure.core.typed :as t :refer [ann]]))

(ann my-keys (All [a] [(t/Map a Any) -> (t/Coll a)])

nice, thanks!

Pretty close to clojure, problem 1: https://gist.github.com/anonymous/6764863