Make geiser find guix package definitions

guix-geiser.el

(defun geiser-edit--goto-line-guix (symbol line)
  (unless (numberp line)
    (goto-char (point-min))
    (when (re-search-forward
           (rx (seq "(define-public"
                    (one-or-more " ")
                    symbol-start (literal (format "%s" symbol)) symbol-end))
           nil t)
      (goto-char (match-beginning 0)))))

(advice-add
 'geiser-edit--goto-line :before-until #'geiser-edit--goto-line-guix)