diff --git a/test/integration/default/controls/package_spec.rb b/test/integration/default/controls/package_spec.rb
index 6ce34b2..6cc20d1 100644
--- a/test/integration/default/controls/package_spec.rb
+++ b/test/integration/default/controls/package_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 control 'Sysctl package' do
   title 'should be installed'