diff --git a/.rubocop.yml b/.rubocop.yml
index adc9df4..e4e8bc7 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,4 +1,6 @@
+---
 require:
+  - rubocop-performance
   - rubocop-rake
   - rubocop-rspec
 
diff --git a/Gemfile b/Gemfile
index b430518..f27e43d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -10,6 +10,7 @@ gem 'pry'
 gem 'rake'
 gem 'rspec'
 gem 'rubocop'
+gem 'rubocop-performance'
 gem 'rubocop-rake'
 gem 'rubocop-rspec'
 gem 'ruby-lsp'