Generate hmac with sha256 in Common Lisp

hmac.lisp

(ql:quickload :ironclad)
(defpackage :test (:use :cl :ironclad))
(in-package :test)

(defun hmac-sha256 (secret data)
   (let* ((secret-bytes (ascii-string-to-byte-array secret))
          (data-bytes (ascii-string-to-byte-array data))
          (h (make-hmac secret-bytes :sha256)))
     (update-hmac h data-bytes)
     (byte-array-to-hex-string (hmac-digest h))))