diff --git a/Gemfile b/Gemfile
index 456d314..c36e2c7 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,7 +2,7 @@
 # the following line to use "https"
 source 'http://rubygems.org'
 
-gem "middleman", "~>3.3.2"
+gem "middleman", "~> 4.3.8"
 gem "middleman-livereload", "~> 3.1.0"
 gem 'bourbon'
 gem 'middleman-deploy'