CPF validator in Clojure

cpf-validator.clj

(ns backend.utils
  (:require
   [swiss-arrows.core :refer :all]))

(defn check-cpf [cpf]
  (let [digits (->> cpf (re-seq #"\d") (map #(Integer. %)))
        blacklisted? (partial re-find #"^12345678909|(\d)\1{10}$")
        formatted? (partial re-find #"^\d{11}$")
        checksum-ok? (fn [digit digits]
                       (-<> (for [i (range digit)] (* (nth digits i) (+ digit 1 (- i))))
                            (apply + <>) (mod 11) (#(if (< % 2) 0 (- 11 %)))
                            (= (nth digits digit))))]
    (and
     (not (blacklisted? cpf))
     (formatted? cpf)
     (checksum-ok? 9 digits)
     (checksum-ok? 10 digits))))