diff --git a/gemfiles/redis_4.gemfile b/gemfiles/redis_4.gemfile
index 701e936..4372f71 100644
--- a/gemfiles/redis_4.gemfile
+++ b/gemfiles/redis_4.gemfile
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # This file was generated by Appraisal
 
 source "https://rubygems.org"
diff --git a/lib/rack/attack/store_proxy/redis_proxy.rb b/lib/rack/attack/store_proxy/redis_proxy.rb
index ca2786c..756c4c6 100644
--- a/lib/rack/attack/store_proxy/redis_proxy.rb
+++ b/lib/rack/attack/store_proxy/redis_proxy.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'delegate'
 
 module Rack
@@ -16,7 +18,7 @@ module Rack
           get(key)
         end
 
-        def write(key, value, options={})
+        def write(key, value, options = {})
           if (expires_in = options[:expires_in])
             setex(key, expires_in, value)
           else
@@ -24,7 +26,7 @@ module Rack
           end
         end
 
-        def increment(key, amount, options={})
+        def increment(key, amount, options = {})
           count = nil
 
           pipelined do
@@ -35,7 +37,7 @@ module Rack
           count.value if count
         end
 
-        def delete(key, options={})
+        def delete(key, _options = {})
           del(key)
         end
       end
diff --git a/spec/acceptance/stores/redis_spec.rb b/spec/acceptance/stores/redis_spec.rb
index 8524db6..2674514 100644
--- a/spec/acceptance/stores/redis_spec.rb
+++ b/spec/acceptance/stores/redis_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative "../../spec_helper"
 
 if defined?(::Redis)