diff --git a/Gemfile b/Gemfile
index e501f76..40c3b22 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,14 +1,14 @@
 # frozen_string_literal: true
 
-source 'https://rubygems.org'
+source "https://rubygems.org"
 
-eval_gemfile 'Gemfile.devtools'
+eval_gemfile "Gemfile.devtools"
 
 gemspec
 
-gem 'backports', '~> 3.15.0', require: false
+gem "backports", "~> 3.15.0", require: false
 
-unless ENV['CI']
-  gem 'byebug', require: false, platforms: :mri
-  gem 'yard',   require: false
+unless ENV["CI"]
+  gem "byebug", require: false, platforms: :mri
+  gem "yard",   require: false
 end
diff --git a/Rakefile b/Rakefile
index 44667d7..b3f2b0d 100755
--- a/Rakefile
+++ b/Rakefile
@@ -1,13 +1,13 @@
 #!/usr/bin/env rake
 # frozen_string_literal: true
 
-require 'bundler/gem_tasks'
-$LOAD_PATH.unshift(File.join(File.dirname(__FILE__), 'lib'))
+require "bundler/gem_tasks"
+$LOAD_PATH.unshift(File.join(File.dirname(__FILE__), "lib"))
 
-require 'rspec/core'
-require 'rspec/core/rake_task'
+require "rspec/core"
+require "rspec/core/rake_task"
 
 task default: :spec
 
-desc 'Run all specs in spec directory'
+desc "Run all specs in spec directory"
 RSpec::Core::RakeTask.new(:spec)
diff --git a/lib/dry/cli.rb b/lib/dry/cli.rb
index 677fa78..b085100 100644
--- a/lib/dry/cli.rb
+++ b/lib/dry/cli.rb
@@ -8,14 +8,14 @@ module Dry
   #
   # @since 0.1.0
   class CLI
-    require 'dry/cli/version'
-    require 'dry/cli/errors'
-    require 'dry/cli/command'
-    require 'dry/cli/registry'
-    require 'dry/cli/parser'
-    require 'dry/cli/usage'
-    require 'dry/cli/banner'
-    require 'dry/cli/inflector'
+    require "dry/cli/version"
+    require "dry/cli/errors"
+    require "dry/cli/command"
+    require "dry/cli/registry"
+    require "dry/cli/parser"
+    require "dry/cli/usage"
+    require "dry/cli/banner"
+    require "dry/cli/inflector"
 
     # Check if command
     #
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index c12417f..182d624 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,14 +1,14 @@
 # frozen_string_literal: true
 
-require_relative 'support/coverage'
+require_relative "support/coverage"
 
-$LOAD_PATH.unshift 'lib'
-require 'dry/cli'
-require_relative './support/rspec'
+$LOAD_PATH.unshift "lib"
+require "dry/cli"
+require_relative "./support/rspec"
 
 %w[support unit].each do |dir|
-  Dir[File.join(Dir.pwd, 'spec', dir, '**', '*.rb')].each do |file|
-    unless RUBY_VERSION < '2.4.0' && file['support/warnings.rb']
+  Dir[File.join(Dir.pwd, "spec", dir, "**", "*.rb")].each do |file|
+    unless RUBY_VERSION < "2.4.0" && file["support/warnings.rb"]
       require_relative file
     end
   end