diff --git a/.rubocop.yml b/.rubocop.yml
index fc88c1c..28f8502 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,3 +1,6 @@
+require:
+  - rubocop-performance
+
 inherit_mode:
   merge:
     - Exclude
diff --git a/lib/rack/attack.rb b/lib/rack/attack.rb
index bc54a82..f4297a5 100644
--- a/lib/rack/attack.rb
+++ b/lib/rack/attack.rb
@@ -67,7 +67,7 @@ module Rack
       end
 
       def safelists
-        @safelists  ||= {}
+        @safelists ||= {}
       end
 
       def blocklists
@@ -75,11 +75,11 @@ module Rack
       end
 
       def throttles
-        @throttles  ||= {}
+        @throttles ||= {}
       end
 
       def tracks
-        @tracks     ||= {}
+        @tracks ||= {}
       end
 
       def safelisted?(request)
@@ -136,7 +136,7 @@ module Rack
     # Set defaults
     @anonymous_blocklists = []
     @anonymous_safelists = []
-    @notifier             = ActiveSupport::Notifications if defined?(ActiveSupport::Notifications)
+    @notifier = ActiveSupport::Notifications if defined?(ActiveSupport::Notifications)
     @blocklisted_response = lambda { |_env| [403, { 'Content-Type' => 'text/plain' }, ["Forbidden\n"]] }
     @throttled_response   = lambda do |env|
       retry_after = (env['rack.attack.match_data'] || {})[:period]
diff --git a/lib/rack/attack/throttle.rb b/lib/rack/attack/throttle.rb
index 071646b..c222325 100644
--- a/lib/rack/attack/throttle.rb
+++ b/lib/rack/attack/throttle.rb
@@ -12,7 +12,7 @@ module Rack
         MANDATORY_OPTIONS.each do |opt|
           raise ArgumentError, "Must pass #{opt.inspect} option" unless options[opt]
         end
-        @limit  = options[:limit]
+        @limit = options[:limit]
         @period = options[:period].respond_to?(:call) ? options[:period] : options[:period].to_i
         @type   = options.fetch(:type, :throttle)
       end
diff --git a/rack-attack.gemspec b/rack-attack.gemspec
index d911931..96aa458 100644
--- a/rack-attack.gemspec
+++ b/rack-attack.gemspec
@@ -37,7 +37,8 @@ Gem::Specification.new do |s|
   s.add_development_dependency "minitest-stub-const", "~> 0.6"
   s.add_development_dependency 'rack-test', "~> 1.0"
   s.add_development_dependency 'rake', "~> 12.3"
-  s.add_development_dependency "rubocop", "0.67.2"
+  s.add_development_dependency "rubocop", "0.74.0"
+  s.add_development_dependency "rubocop-performance", "~> 1.4.1"
   s.add_development_dependency "timecop", "~> 0.9.1"
 
   # byebug only works with MRI