diff --git a/.rubocop.yml b/.rubocop.yml
index 3e2f35dc..ca4bdf59 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,6 +1,6 @@
 AllCops:
   DisabledByDefault: true
-  TargetRubyVersion: 1.9.3
+  TargetRubyVersion: 2.2
   DisplayCopNames: true
   StyleGuideCopsOnly: false
   Exclude:
@@ -51,41 +51,5 @@ Style/MethodDefParentheses:
 Style/TrailingCommaInArguments:
   Enabled: true
 
-Performance/Count:
-  Enabled: true
-
-Performance/Detect:
-  Enabled: true
-
-Performance/EndWith:
-  Enabled: true
-
-Performance/FlatMap:
-  Enabled: true
-
-Performance/HashEachMethods:
-  Enabled: true
-
-Performance/RangeInclude:
-  Enabled: true
-
-Performance/RedundantMerge:
-  Enabled: true
-
-Performance/RedundantSortBy:
-  Enabled: true
-
-Performance/ReverseEach:
-  Enabled: true
-
-Performance/Sample:
-  Enabled: true
-
-Performance/Size:
-  Enabled: true
-
-Performance/StartWith:
-  Enabled: true
-
-Performance/TimesMap:
+Performance:
   Enabled: true
diff --git a/lib/puma/dsl.rb b/lib/puma/dsl.rb
index 220c4f73..0ac577d7 100644
--- a/lib/puma/dsl.rb
+++ b/lib/puma/dsl.rb
@@ -493,7 +493,7 @@ module Puma
       when Hash
         if hdr = val[:header]
           @options[:remote_address] = :header
-          @options[:remote_address_header] = "HTTP_" + hdr.upcase.gsub("-", "_")
+          @options[:remote_address_header] = "HTTP_" + hdr.upcase.tr("-", "_")
         else
           raise "Invalid value for set_remote_address - #{val.inspect}"
         end
diff --git a/lib/puma/rack/builder.rb b/lib/puma/rack/builder.rb
index 7676ad54..301da500 100644
--- a/lib/puma/rack/builder.rb
+++ b/lib/puma/rack/builder.rb
@@ -110,7 +110,7 @@ module Puma::Rack
 
           has_options = false
           server.valid_options.each do |name, description|
-            next if name.to_s.match(/^(Host|Port)[^a-zA-Z]/) # ignore handler's host and port options, we do our own.
+            next if name.to_s =~ /^(Host|Port)[^a-zA-Z]/ # ignore handler's host and port options, we do our own.
             info << "  -O %-21s %s" % [name, description]
             has_options = true
           end
diff --git a/test/test_integration.rb b/test/test_integration.rb
index 49cc99a4..e13330af 100644
--- a/test/test_integration.rb
+++ b/test/test_integration.rb
@@ -181,7 +181,7 @@ class TestIntegration < Minitest::Test
     until done
       @events.stdout.rewind
       log = @events.stdout.readlines.join("")
-      if log.match(/- Worker \d \(pid: \d+\) booted, phase: 1/)
+      if log =~ /- Worker \d \(pid: \d+\) booted, phase: 1/
         assert_match(/TERM sent/, log)
         assert_match(/- Worker \d \(pid: \d+\) booted, phase: 1/, log)
         done = true
diff --git a/test/test_puma_server_ssl.rb b/test/test_puma_server_ssl.rb
index d479203f..147ee3de 100644
--- a/test/test_puma_server_ssl.rb
+++ b/test/test_puma_server_ssl.rb
@@ -144,7 +144,7 @@ class TestPumaServerSSLClient < Minitest::Test
     http.use_ssl = true
     http.verify_mode = OpenSSL::SSL::VERIFY_NONE
 
-    blk.call(http)
+    yield(http)
 
     client_error = false
     begin