   "Kill the filesystem watcher, if it is running.
 If there is an unexpected error, signal a warning and return nil."
   (interactive)
-  (let ((python (straight--watcher-file "virtualenv" "bin" "python")))
+  (let ((python (straight--watcher-python)))
     (when (file-executable-p python)
       (straight--warn-call
        python "-m" "straight_watch" "stop"

  "Set up the virtualenv for the filesystem watcher.
If it fails, signal a warning and return nil."
  (let* ((virtualenv (straight--watcher-dir "virtualenv"))
         (python (straight--watcher-file
                  "virtualenv" "bin" "python"))
         (straight-dir (file-name-directory straight--this-file))
         (watcher-dir (expand-file-name "watcher" straight-dir))
         (version-from (expand-file-name "version" watcher-dir))

      (cl-return-from straight-watcher-start))
    (message "Setting up filesystem watcher...done"))
  (with-current-buffer (straight-watcher--make-process-buffer)
    (let* ((python (straight--watcher-python))
           (cmd (list
                 python "-m" "straight_watch" "start"
                 (straight--watcher-file "process")
