helm-setup.el

(unless (version< emacs-version "26")
  (ensure-package-installed 'helm)

  (setq default-frame-alist '((vertical-scroll-bars . nil)
                              (tool-bar-lines . 0)
                              (menu-bar-lines . 0)
                              (fullscreen . nil)))
  (blink-cursor-mode -1)
  (require 'helm-config)
  (helm-mode 1)
  (define-key global-map [remap find-file] 'helm-find-files)
  (define-key global-map [remap occur] 'helm-occur)
  (define-key global-map [remap list-buffers] 'helm-buffers-list)
  (define-key global-map [remap dabbrev-expand] 'helm-dabbrev)
  (define-key global-map [remap execute-extended-command] 'helm-M-x)
  (unless (boundp 'completion-in-region-function)
    (define-key lisp-interaction-mode-map [remap completion-at-point] 'helm-lisp-completion-at-point)
    (define-key emacs-lisp-mode-map       [remap completion-at-point] 'helm-lisp-completion-at-point))
 )