diff --git a/Gemfile b/Gemfile
index c1e0881..f107c5a 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 source 'https://rubygems.org/'
 
 gem 'github-pages'
diff --git a/Rakefile b/Rakefile
index 5e8c3d5..ad66782 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 desc 'Run jekyll server'
 task :serve do
   exec 'bundle exec jekyll serve --incremental'