diff --git a/site/Gemfile b/site/Gemfile
index c0df4e1b627..1a25ce05f52 100644
--- a/site/Gemfile
+++ b/site/Gemfile
@@ -1,6 +1,6 @@
 source 'https://rubygems.org'
 
-gem 'middleman', '~>3'
+gem 'middleman', '~> 4', '>= 4.1.8'
 gem 'middleman-livereload', '~>3'
 gem 'middleman-syntax', '~>3'
 gem 'middleman-blog', '~>3'