diff --git a/.rubocop.yml b/.rubocop.yml
index 7063d2c..0fe7026 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -7,3 +7,4 @@ Style/ClassAndModuleChildren:
 # General config to enable every `Pendent` cop
 AllCops:
   NewCops: enable
+  TargetRubyVersion: 2.5
diff --git a/Gemfile b/Gemfile
index f9fe06b..2cc08ab 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,7 +2,11 @@
 
 source 'https://rubygems.org'
 
-gem 'rake', '~> 12.0'
+group :development, :test do
+  gem 'fakeredis', '~> 0.9'
+  gem 'minitest', '~> 5.0'
+  gem 'rake', '~> 12.0'
+end
 
 # Specify your gem's dependencies in clock-limiter.gemspec
 gemspec
diff --git a/clock-limiter.gemspec b/clock-limiter.gemspec
index 59651a6..22956d2 100644
--- a/clock-limiter.gemspec
+++ b/clock-limiter.gemspec
@@ -29,6 +29,4 @@ Gem::Specification.new do |spec|
 
   # Dependencies
   spec.add_runtime_dependency 'redis', '>= 3'
-  spec.add_development_dependency 'fakeredis', '~> 0.9'
-  spec.add_development_dependency 'minitest', '~> 5.0'
 end
diff --git a/lib/clock/limiter/limiter.rb b/lib/clock/limiter/limiter.rb
index 222f150..8ddc906 100644
--- a/lib/clock/limiter/limiter.rb
+++ b/lib/clock/limiter/limiter.rb
@@ -129,7 +129,7 @@ def key(period, group_key)
     # according to the [Clock::Limiter::Configuration#time_provider]
     #
     # @param [Clock::Limiter::Period] period
-    def current_period(period)
+    def current_period(period) # rubocop:disable Metrics/AbcSize, Metrics/MethodLength
       case period
       when Period::SECOND
         Clock::Limiter.configuration.time_provider.call.sec
diff --git a/test/clock/limiter_test.rb b/test/clock/limiter_test.rb
index bf7208e..00ed0ee 100644
--- a/test/clock/limiter_test.rb
+++ b/test/clock/limiter_test.rb
@@ -41,7 +41,7 @@ def test_properly_configures_gem
     assert Clock::Limiter.configuration.time_provider
   end
 
-  def test_good_path
+  def test_good_path # rubocop:disable Metrics/MethodLength
     configure_gem
 
     failed_count = 0
@@ -65,7 +65,7 @@ def call
     assert_equal 2, failed_count
   end
 
-  def test_with_clock_limiter_with_group_key
+  def test_with_clock_limiter_with_group_key # rubocop:disable Metrics/MethodLength
     configure_gem
 
     failed_groups = []