diff --git a/.gitignore b/.gitignore
index c5e2ad0d..12bc32bc 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,7 +12,6 @@ tmp
 t/
 .rbx/
 Gemfile.lock
-gemfiles/2.1-Gemfile.lock
 .idea/
 /test/test_puma.state
 /test/test_server.sock
diff --git a/gemfiles/2.1-Gemfile b/gemfiles/2.1-Gemfile
deleted file mode 100644
index d41f64ec..00000000
--- a/gemfiles/2.1-Gemfile
+++ /dev/null
@@ -1,14 +0,0 @@
-source "https://rubygems.org"
-
-gemspec path: ".."
-
-gem "rdoc"
-gem "rake-compiler"
-
-gem "rack", "~> 1.6"
-gem "minitest", '~> 5.9'
-gem "minitest-retry"
-
-gem "jruby-openssl", :platform => "jruby"
-
-gem "rubocop", "~> 0.50.0"
diff --git a/puma.gemspec b/puma.gemspec
index c0e4a596..e1348d2c 100644
--- a/puma.gemspec
+++ b/puma.gemspec
@@ -18,5 +18,5 @@ Gem::Specification.new do |s|
             %w[History.md LICENSE README.md]
   s.homepage = "http://puma.io"
   s.license = "BSD-3-Clause"
-  s.required_ruby_version = Gem::Requirement.new(">= 1.9.3")
+  s.required_ruby_version = Gem::Requirement.new(">= 2.2")
 end