diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index c0e06ff..08b1de0 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -47,9 +47,8 @@ have before they can be landed:
   place, but if you diverge from how things are done at the moment the patch
   won't get accepted as-is.
 
-* Support Ruby 2.2 and higher.  We maintain the same Ruby version
-  compatibility as Rack itself.  We use [Travis CI test
-  runs](https://travis-ci.org/rack/rack-contrib) to validate this.
+* Support Ruby 2.7 and higher.  We maintain the same Ruby version
+  compatibility as Rack itself.
 
 * Require no external dependencies.  Some existing middleware depends on
   additional gems in order to function; we feel that this is an
diff --git a/Gemfile b/Gemfile
index 4d37ed3..318b49e 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,7 +5,7 @@ source 'https://rubygems.org'
 gemspec
 
 gem 'i18n', '~> 0.6', '>= 0.6.8'
-gem 'json', '~> 2.0'
+gem 'json', '> 3.0'
 gem 'mime-types', '~> 3.0'
 gem 'minitest', '~> 5.6'
 gem 'minitest-hooks', '~> 1.0'
diff --git a/lib/rack/contrib/json_body_parser.rb b/lib/rack/contrib/json_body_parser.rb
index e98d9ad..db1a50b 100644
--- a/lib/rack/contrib/json_body_parser.rb
+++ b/lib/rack/contrib/json_body_parser.rb
@@ -40,7 +40,7 @@ class JSONBodyParser
       }.call(),
     }.freeze
 
-    DEFAULT_PARSER = ->(body) { JSON.parse(body, create_additions: false) }
+    DEFAULT_PARSER = ->(body) { JSON.parse(body) }
 
     def initialize(
       app,
diff --git a/lib/rack/contrib/post_body_content_type_parser.rb b/lib/rack/contrib/post_body_content_type_parser.rb
index 0ce71a9..a325b63 100644
--- a/lib/rack/contrib/post_body_content_type_parser.rb
+++ b/lib/rack/contrib/post_body_content_type_parser.rb
@@ -70,7 +70,7 @@ class PostBodyContentTypeParser
     def initialize(app, &block)
       warn "[DEPRECATION] `PostBodyContentTypeParser` is deprecated. Use `JSONBodyParser` as a drop-in replacement."
       @app = app
-      @block = block || Proc.new { |body| JSON.parse(body, :create_additions => false) }
+      @block = block || Proc.new { |body| JSON.parse(body) }
     end
 
     def call(env)
diff --git a/rack-contrib.gemspec b/rack-contrib.gemspec
index 94dc625..0bb7ffa 100644
--- a/rack-contrib.gemspec
+++ b/rack-contrib.gemspec
@@ -28,8 +28,9 @@ Gem::Specification.new do |s|
 
   s.extra_rdoc_files = %w[README.md COPYING]
 
-  s.required_ruby_version = '>= 2.2.2'
+  s.required_ruby_version = '>= 2.7.3'
 
+  s.add_runtime_dependency 'json', '> 3.0'
   s.add_runtime_dependency 'rack', '< 4'
 
   s.homepage = "https://github.com/rack/rack-contrib/"
diff --git a/test/spec_rack_garbagecollector.rb b/test/spec_rack_garbagecollector.rb
index 183f0f1..e239fe9 100644
--- a/test/spec_rack_garbagecollector.rb
+++ b/test/spec_rack_garbagecollector.rb
@@ -4,12 +4,19 @@
 require 'rack/mock'
 require 'rack/contrib/garbagecollector'
 
-describe 'Rack::GarbageCollector' do
+describe Rack::GarbageCollector do
+
+  def app
+    -> (env) { [200, {}, ['Hello World']] }
+  end
+
+  def mock_env
+    headers = { 'REQUEST_METHOD' => 'POST' }
+    Rack::MockRequest.env_for '/', headers
+  end
 
   specify 'starts the garbage collector after each request' do
-    app = lambda { |env|
-      [200, {'Content-Type'=>'text/plain'}, ['Hello World']] }
-    Rack::Lint.new(Rack::GarbageCollector.new(app).call({}))
+    Rack::Lint.new(Rack::GarbageCollector.new(app)).call(mock_env)
   end
 
 end
diff --git a/test/spec_rack_json_body_parser_spec.rb b/test/spec_rack_json_body_parser_spec.rb
index d2930cc..e6a77fc 100644
--- a/test/spec_rack_json_body_parser_spec.rb
+++ b/test/spec_rack_json_body_parser_spec.rb
@@ -26,36 +26,36 @@ def create_parser(app, **args, &block)
 
   specify "should parse 'application/json' requests" do
     res = create_parser(app).call(mock_env)
-    _(res[2].to_enum.to_a.join).must_equal '{"key"=>"value"}'
+    _(res[2].to_enum.to_a.join).must_equal({"key"=>"value"}.inspect)
   end
 
   specify "should parse 'application/json; charset=utf-8' requests" do
     env = mock_env(type: 'application/json; charset=utf-8')
     res = create_parser(app).call(env)
-    _(res[2].to_enum.to_a.join).must_equal '{"key"=>"value"}'
+    _(res[2].to_enum.to_a.join).must_equal({"key"=>"value"}.inspect)
   end
 
   specify "should parse 'application/json' requests with an empty body" do
     res = create_parser(app).call(mock_env(input: ''))
-    _(res[2].to_enum.to_a.join).must_equal '{}'
+    _(res[2].to_enum.to_a.join).must_equal({}.inspect)
   end
 
   specify "shouldn't affect form-urlencoded requests" do
     env = mock_env(input: 'key=value', type: 'application/x-www-form-urlencoded')
     res = create_parser(app).call(env)
-    _(res[2].to_enum.to_a.join).must_equal '{"key"=>"value"}'
+    _(res[2].to_enum.to_a.join).must_equal({"key"=>"value"}.inspect)
   end
 
   specify "should not parse non-json media types" do
     env = mock_env(type: 'text/plain')
     res = create_parser(app).call(env)
-    _(res[2].to_enum.to_a.join).must_equal '{}'
+    _(res[2].to_enum.to_a.join).must_equal({}.inspect)
   end
 
   specify "shouldn't parse or error when CONTENT_TYPE is nil" do
     env = mock_env(type: nil)
     res = create_parser(app).call(env)
-    _(res[2].to_enum.to_a.join).must_equal %Q({"{\\"key\\": \\"value\\"}"=>nil})
+    _(res[2].to_enum.to_a.join).must_equal({'{"key": "value"}' => nil}.inspect)
   end
 
   specify "should not rescue JSON:ParserError raised by the app" do
@@ -91,7 +91,7 @@ class CustomParserError < StandardError; end
         { 'payload' => JSON.parse(body) }
       end
       res = parser.call(mock_env)
-      _(res[2].to_enum.to_a.join).must_equal '{"payload"=>{"key"=>"value"}}'
+      _(res[2].to_enum.to_a.join).must_equal({"payload"=>{"key"=>"value"}}.inspect)
     end
 
     specify "should accept an array of HTTP verbs to parse" do
@@ -99,35 +99,35 @@ class CustomParserError < StandardError; end
       parser = create_parser(app, verbs: %w[GET])
 
       res = parser.call(env)
-      _(res[2].to_enum.to_a.join).must_equal '{"key"=>"value"}'
+      _(res[2].to_enum.to_a.join).must_equal({"key"=>"value"}.inspect)
 
       res = parser.call(mock_env)
-      _(res[2].to_enum.to_a.join).must_equal '{}'
+      _(res[2].to_enum.to_a.join).must_equal({}.inspect)
     end
 
     specify "should accept an Array of media-types to parse" do
       parser = create_parser(app, media: ['application/json', 'text/plain'])
       env = mock_env(type: 'text/plain')
       res = parser.call(env)
-      _(res[2].to_enum.to_a.join).must_equal '{"key"=>"value"}'
+      _(res[2].to_enum.to_a.join).must_equal({"key"=>"value"}.inspect)
 
       html_env = mock_env(type: 'text/html')
       res = parser.call(html_env)
-      _(res[2].to_enum.to_a.join).must_equal '{}'
+      _(res[2].to_enum.to_a.join).must_equal({}.inspect)
     end
 
     specify "should accept a Regexp as a media-type matcher" do
       parser = create_parser(app, media: /json/)
       env = mock_env(type: 'weird/json.odd')
       res = parser.call(env)
-      _(res[2].to_enum.to_a.join).must_equal '{"key"=>"value"}'
+      _(res[2].to_enum.to_a.join).must_equal({"key"=>"value"}.inspect)
     end
 
     specify "should accept a String as a media-type matcher" do
       parser = create_parser(app, media: 'application/vnd.api+json')
       env = mock_env(type: 'application/vnd.api+json')
       res = parser.call(env)
-      _(res[2].to_enum.to_a.join).must_equal '{"key"=>"value"}'
+      _(res[2].to_enum.to_a.join).must_equal({"key"=>"value"}.inspect)
     end
   end
 end