diff --git a/examples/rails_4_button_example/Gemfile.lock b/examples/rails_4_button_example/Gemfile.lock
index 9597a9d..2413f49 100644
--- a/examples/rails_4_button_example/Gemfile.lock
+++ b/examples/rails_4_button_example/Gemfile.lock
@@ -101,7 +101,7 @@ GEM
       activesupport (= 4.2.1)
       rake (>= 0.8.7)
       thor (>= 0.18.1, < 2.0)
-    rake (10.4.2)
+    rake (13.0.1)
     rdoc (4.2.0)
     sass (3.4.13)
     sass-rails (5.0.3)