ivy compliant vertico config

my-vertico-init.el

(use-package vertico
  ;; using quelpa until elpa version contains vertico-preselect
  :quelpa
  :ensure t
  :demand
  :config
  (setq vertico-cycle t)
  (setq vertico-preselect 'directory)
  :init
  (vertico-mode)
  ;; make things compatible with my ivy muscle memory
  ;; if first candidate is a directory then "/" should
  ;; vertico-insert, if not, then it should just do the
  ;; char
  (defun my/vertico-insert ()
    (interactive)
    (let* ((mb (minibuffer-contents-no-properties))
           (lc (if (string= mb "") mb (substring mb -1))))
      ;; make sure we can still reset to ~ and // ivy style, also consider tramp prefixes
      (cond ((string-match-p "^[/~:]" lc) (self-insert-command 1 ?/)) 
            ((file-directory-p (vertico--candidate)) (vertico-insert))
            (t (self-insert-command 1 ?/)))))
  :bind (:map vertico-map
              ("/" . #'my/vertico-insert)))

;; Configure directory extension.
(use-package vertico-directory
  ;; using quelpa until elpa version contains vertico-preselect
  :quelpa
  :after vertico
  :ensure t
  :demand
  ;; More convenient directory navigation commands
  :bind (:map vertico-map
              ("RET"   . vertico-directory-enter)
              ("DEL"   . vertico-directory-delete-char)
              ("M-DEL" . vertico-directory-delete-word))
  ;; Tidy shadowed file names
  :hook (rfn-eshadow-update-overlay . vertico-directory-tidy))