diff --git a/comment/Gemfile b/comment/Gemfile
index 0eb06eb..bd56f32 100644
--- a/comment/Gemfile
+++ b/comment/Gemfile
@@ -7,3 +7,4 @@ gem 'puma'
 gem 'prometheus-client'
 gem 'rack'
 gem 'rufus-scheduler'
+gem 'tzinfo-data'