diff --git a/.rubocop.yml b/.rubocop.yml
new file mode 100644
index 0000000000..d65f9ae0fe
--- /dev/null
+++ b/.rubocop.yml
@@ -0,0 +1,88 @@
+AllCops:
+  DisabledByDefault: true
+  TargetRubyVersion: 1.9.3
+  DisplayCopNames: true
+  StyleGuideCopsOnly: false
+  Exclude:
+    - 'tmp/**/*'
+    - 'gemfiles/vendor/**/*'
+    - 'vendor/**/*'
+    - 'Rakefile'
+
+Layout/SpaceAfterColon:
+  Enabled: true
+
+Layout/SpaceAroundKeyword:
+  Enabled: true
+
+Layout/SpaceBeforeFirstArg:
+  Enabled: true
+
+Layout/SpaceInsideParens:
+  Enabled: true
+
+Layout/Tab:
+  Enabled: true
+
+Layout/TrailingBlankLines:
+  Enabled: true
+
+Layout/TrailingWhitespace:
+  Enabled: true
+
+Lint/Debugger:
+  Enabled: true
+
+Style/MethodDefParentheses:
+  Enabled: true
+
+Style/MethodName:
+  Enabled: true
+  EnforcedStyle: snake_case
+  Exclude:
+    - 'test/**/**'
+
+Style/TrailingCommaInArguments:
+  Enabled: true
+
+Style/VariableName:
+  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:
+  Enabled: true
diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
new file mode 100644
index 0000000000..7bbab17625
--- /dev/null
+++ b/.rubocop_todo.yml
@@ -0,0 +1,86 @@
+inherit_from: "./.rubocop.yml"
+
+# 29 offenses
+Layout/SpaceAroundOperators:
+  Enabled: true
+
+# 21 offenses
+Layout/SpaceInsideBlockBraces:
+  Enabled: true
+
+# 16 offenses
+Layout/SpaceAroundEqualsInParameterDefault:
+  Enabled: true
+  EnforcedStyle: no_space
+
+# 15 offenses
+Layout/SpaceBeforeBlockBraces:
+  Enabled: true
+
+# 15 offenses
+Layout/SpaceInsideHashLiteralBraces:
+  Enabled: true
+  EnforcedStyle: no_space
+
+# 8 offenses
+Layout/EmptyLines:
+  Enabled: true
+
+# 4 offenses
+Layout/EmptyLinesAroundClassBody:
+  Enabled: true
+  Exclude:
+    - 'test/**/*'
+
+# 6 offenses
+Layout/EmptyLinesAroundMethodBody:
+  Enabled: true
+
+# 5 offenses
+Layout/EmptyLinesAroundModuleBody:
+  Enabled: true
+
+# 5 offenses
+Layout/IndentationWidth:
+  Enabled: true
+
+# 3 offenses
+Layout/AccessModifierIndentation:
+  EnforcedStyle: indent
+
+# 2 offenses
+Style/WhileUntilModifier:
+  Enabled: true
+
+# 1 offense
+Style/TernaryParentheses:
+  Enabled: true
+
+# >200 offenses for 80
+# 58 offenses for 100
+# 18 offenses for 120
+Metrics/LineLength:
+  Max: 120
+  AllowHeredoc: true
+  AllowURI: true
+  URISchemes:
+    - http
+    - https
+  IgnoreCopDirectives: false
+  IgnoredPatterns: []
+
+# 1 offense
+Metrics/ParameterLists:
+  Max: 5
+
+# 1 offense
+Performance/RedundantMatch:
+  Enabled: true
+
+# 1 offense
+Performance/RedundantBlockCall:
+  Enabled: true
+
+# 1 offense
+Performance/StringReplacement:
+  Enabled: true
\ No newline at end of file
diff --git a/.travis.yml b/.travis.yml
index 625d44659d..fc1b706871 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,7 +7,7 @@ before_install:
   # bundler installation needed for jruby-head
   # https://github.com/travis-ci/travis-ci/issues/5861
   - gem install bundler -v 1.11.2
-script: "TESTOPTS=-v bundle exec rake test"
+script: "TESTOPTS=-v bundle exec rake"
 branches:
   only: [master]
 rvm:
diff --git a/Gemfile b/Gemfile
index a01c7005ac..51c7ad4933 100644
--- a/Gemfile
+++ b/Gemfile
@@ -12,3 +12,5 @@ gem "rack", "< 3.0"
 gem "minitest", "~> 5.9"
 
 gem "jruby-openssl", :platform => "jruby"
+
+gem "rubocop", "~> 0.49.1"
diff --git a/Rakefile b/Rakefile
index ec34c77744..bd51f19634 100644
--- a/Rakefile
+++ b/Rakefile
@@ -2,6 +2,10 @@ require "bundler/setup"
 require "hoe"
 require "rake/extensiontask"
 require "rake/javaextensiontask"
+require "rubocop/rake_task"
+
+# Add rubocop task
+RuboCop::RakeTask.new
 
 IS_JRUBY = defined?(RUBY_ENGINE) ? RUBY_ENGINE == "jruby" : false
 
@@ -163,3 +167,5 @@ namespace :test do
     task :all => [:test, "test:integration"]
   end
 end
+
+task :default => [:rubocop, :test]
diff --git a/examples/qc_config.rb b/examples/qc_config.rb
index 26c3786e20..b67be07dde 100644
--- a/examples/qc_config.rb
+++ b/examples/qc_config.rb
@@ -6,7 +6,7 @@
   CA[:domainname] = domainname
   CA[:CA_dir] = File.join Dir.pwd, "CA"
   CA[:password] = 'puma'
-  
+
   CERTS << {
     :type => 'server',
     :hostname => 'puma'
diff --git a/gemfiles/2.1-Gemfile b/gemfiles/2.1-Gemfile
index a929221a98..67e3f1b2b7 100644
--- a/gemfiles/2.1-Gemfile
+++ b/gemfiles/2.1-Gemfile
@@ -10,3 +10,5 @@ gem "rack", "~> 1.6"
 gem "minitest", '~> 5.9'
 
 gem "jruby-openssl", :platform => "jruby"
+
+gem "rubocop", "~> 0.49.1"
diff --git a/lib/puma/jruby_restart.rb b/lib/puma/jruby_restart.rb
index f92a73ee37..da944e8ce7 100644
--- a/lib/puma/jruby_restart.rb
+++ b/lib/puma/jruby_restart.rb
@@ -80,4 +80,3 @@ def self.daemon_start(dir, argv)
     end
   end
 end
-
diff --git a/lib/puma/plugin/tmp_restart.rb b/lib/puma/plugin/tmp_restart.rb
index c0fb87b845..7c2c402abd 100644
--- a/lib/puma/plugin/tmp_restart.rb
+++ b/lib/puma/plugin/tmp_restart.rb
@@ -32,4 +32,3 @@ def start(launcher)
     end
   end
 end
-
diff --git a/test/config/state_file_testing_config.rb b/test/config/state_file_testing_config.rb
index 47f8bc1b1b..a920fb0dce 100644
--- a/test/config/state_file_testing_config.rb
+++ b/test/config/state_file_testing_config.rb
@@ -11,4 +11,3 @@
 on_restart { 1 }
 after_worker_boot { 1 }
 lowlevel_error_handler { 1 }
-
diff --git a/test/shell/t1.rb b/test/shell/t1.rb
index e0a529d7ee..ce2f3e0c8b 100644
--- a/test/shell/t1.rb
+++ b/test/shell/t1.rb
@@ -16,4 +16,3 @@
 else
   exit 1
 end
-
diff --git a/test/shell/t3.rb b/test/shell/t3.rb
index cb52428aa6..2d48bca3f0 100644
--- a/test/shell/t3.rb
+++ b/test/shell/t3.rb
@@ -9,7 +9,7 @@
 
 worker_index_within_number_of_workers = !File.file?("t3-worker-3-pid")
 
-system "kill `cat t3-pid`" 
+system "kill `cat t3-pid`"
 
 File.unlink "t3-pid" if File.file? "t3-pid"
 File.unlink "t3-worker-0-pid" if File.file? "t3-worker-0-pid"
@@ -22,4 +22,3 @@
 else
   exit 1
 end
-
diff --git a/test/test_rack_handler.rb b/test/test_rack_handler.rb
index 4859b5014f..79a790cc7e 100644
--- a/test/test_rack_handler.rb
+++ b/test/test_rack_handler.rb
@@ -179,4 +179,3 @@ def test_user_port_wins_over_config
     end
   end
 end
-
diff --git a/tools/trickletest.rb b/tools/trickletest.rb
index e19ed718b5..11da57a640 100644
--- a/tools/trickletest.rb
+++ b/tools/trickletest.rb
@@ -31,7 +31,7 @@ def do_test(st, chunk)
 puts "length: #{content.length}"
 
 threads = []
-ARGV[1].to_i.times do 
+ARGV[1].to_i.times do
   t = Thread.new do
     size = 100
     puts ">>>> #{size} sized chunks"