gist.el

    (let ((url-request-method "POST")
          (url-request-extra-headers `(("Content-Type" . "application/json") ("User-Agent" . "gist.el") ("Authorization" . ,(concat "Bearer " oauth-token))))
          (url-request-data (json-encode payload)))
      (url-retrieve "https://api.github.com/gists" 'my/gist-handle-response))))

(defun my/gist-handle-response (response)
  "Process content of RESPONSE and extract link."
  (let* ((status-line (buffer-substring-no-properties (line-beginning-position) (line-end-position)))
         (status-code (nth 1 (split-string status-line " "))))

    (message status-code)
    (unless (not (string-equal status-code "201"))
      (user-error "There was a problem with GitHub API, try again later"))