diff --git a/Gemfile b/Gemfile
index 2dce3e5..0c4b9b6 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-source 'http://rubygems.org'
+source 'https://rubygems.org'
 gemspec
 
 group :test do