diff --git a/Gemfile b/Gemfile
index 1d482a7..007383c 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,3 +1,4 @@
 source 'https://rubygems.org'
 
 gem 'github-pages', '>=180', group: :jekyll_plugins
+gem 'wdm', '>= 0.1.0' if Gem.win_platform?