.spacemacs.el

;; Put in dotspacemacs/user-config
(defun my/use-eslint-from-node-modules ()
  (let* ((root (locate-dominating-file
                (or (buffer-file-name) default-directory)
                (lambda (dir) (file-executable-p
                               (expand-file-name "node_modules/.bin/eslint"
                                                 dir)))))
         (eslint (and root
                      (expand-file-name "node_modules/.bin/eslint"
                                        root))))
    (when (and eslint (file-executable-p eslint))
      (setq-local flycheck-javascript-eslint-executable eslint))))
(add-hook 'flycheck-mode-hook #'my/use-eslint-from-node-modules)