@qqq the sample.project.clj documents all the available options (https://github.com/technomancy/leiningen/blob/master/sample.project.clj)

(defproject foobar "0.1.0-SNAPSHOT"
  :description "FIXME: write description"
  :url ""
  :license {:name "Eclipse Public License"
            :url ""}
  :dependencies [;; clojure core
                 [org.clojure/clojure "1.9.0-beta2"]
                 [portkey "0.1.0-SNAPSHOT"]]
  :profiles {:repl {:plugins [[cider/cider-nrepl "0.16.0-SNAPSHOT"]]}}
  :repl-options {:port 3000})