diff --git a/sinatra-contrib/sinatra-contrib.gemspec b/sinatra-contrib/sinatra-contrib.gemspec
index fb6fdcc7..6cde1f2e 100644
--- a/sinatra-contrib/sinatra-contrib.gemspec
+++ b/sinatra-contrib/sinatra-contrib.gemspec
@@ -215,6 +215,8 @@ Gem::Specification.new do |s|
     "spec/params_spec.rb",
   ]
 
+  s.required_ruby_version = '>= 2.2.0'
+
   s.add_dependency "sinatra", "~> 1.4"
   s.add_dependency "backports", ">= 2.0"
   s.add_dependency "tilt",      ">= 1.3", "< 3"