diff --git a/docs/Gemfile b/docs/Gemfile
index ecbd3fec..7840e3b9 100644
--- a/docs/Gemfile
+++ b/docs/Gemfile
@@ -2,6 +2,7 @@ source "https://rubygems.org"
 
 gem "github-pages", group: :jekyll_plugins
 
+gem "tzinfo-data"
 gem "wdm", "~> 0.1.0" if Gem.win_platform?
 
 # If you have any plugins, put them here!