diff --git a/README.md b/README.md
index df7ae07..38623c9 100644
--- a/README.md
+++ b/README.md
@@ -8,7 +8,7 @@ To use `lean4-mode` in Emacs, add the following to your `init.el`:
 ;; You need to modify the following line
 (setq load-path (cons "/path/to/lean4-mode" load-path))
 
-(setq lean4-mode-required-packages '(dash flycheck lsp-mode magit-section s))
+(setq lean4-mode-required-packages '(dash flycheck lsp-mode magit-section))
 
 (require 'package)
 (add-to-list 'package-archives '("melpa" . "http://melpa.org/packages/"))
diff --git a/lean4-info.el b/lean4-info.el
index 107cfec..8b8f26e 100644
--- a/lean4-info.el
+++ b/lean4-info.el
@@ -153,7 +153,7 @@ The buffer is supposed to be the *Lean Goal* buffer."
          (goto-char 0)
          (while (re-search-forward "\\(\\sw+\\)✝\\([¹²³⁴-⁹⁰]*\\)" nil t)
            (replace-match
-            (propertize (s-concat (match-string-no-properties 1) (match-string-no-properties 2))
+            (propertize (concat (match-string-no-properties 1) (match-string-no-properties 2))
                         'font-lock-face 'font-lock-comment-face)
             'fixedcase 'literal)))))))
 
diff --git a/lean4-mode.el b/lean4-mode.el
index b8de78c..6124cba 100644
--- a/lean4-mode.el
+++ b/lean4-mode.el
@@ -10,7 +10,7 @@
 ;; Maintainer: Sebastian Ullrich <sebasti@nullri.ch>
 ;; Created: Jan 09, 2014
 ;; Keywords: languages
-;; Package-Requires: ((emacs "27.1") (dash "2.18.0") (s "1.10.0") (flycheck "30") (magit-section "2.90.1") (lsp-mode "8.0.0"))
+;; Package-Requires: ((emacs "27.1") (dash "2.18.0") (flycheck "30") (magit-section "2.90.1") (lsp-mode "8.0.0"))
 ;; URL: https://github.com/leanprover/lean4-mode
 ;; SPDX-License-Identifier: Apache-2.0
 
diff --git a/lean4-util.el b/lean4-util.el
index bdd2598..0394c59 100644
--- a/lean4-util.el
+++ b/lean4-util.el
@@ -27,7 +27,6 @@
 ;;; Code:
 
 (require 'cl-lib)
-(require 's)
 (require 'dash)
 (require 'lean4-settings)
 
@@ -37,7 +36,6 @@ Try to find an executable named `lean4-executable-name' in variable `exec-path'.
 On succsess, return path to the directory with this executable."
   (let ((root (executable-find lean4-executable-name)))
     (when root
-      (setq lean4-rootdir )
       (setq lean4-rootdir (file-name-directory (directory-file-name (directory-file-name root)))))
     lean4-rootdir))