diff --git a/examples/waterdrop/Gemfile b/examples/waterdrop/Gemfile
index a2e2b6f..4c276fe 100644
--- a/examples/waterdrop/Gemfile
+++ b/examples/waterdrop/Gemfile
@@ -2,5 +2,5 @@ source "https://rubygems.org"
 
 gem "aws-msk-iam-sasl-signer"
 gem "base64"
-gem 'waterdrop'
 gem "rexml", "~> 3.2"
+gem "waterdrop"
diff --git a/examples/waterdrop/oauth_token_refresher.rb b/examples/waterdrop/oauth_token_refresher.rb
index ff53810..3f8786a 100644
--- a/examples/waterdrop/oauth_token_refresher.rb
+++ b/examples/waterdrop/oauth_token_refresher.rb
@@ -10,7 +10,7 @@ def on_oauthbearer_token_refresh(event)
     event[:bearer].oauthbearer_set_token(
       token: token.token,
       lifetime_ms: token.expiration_time_ms,
-      principal_name: 'kafka-cluster'
+      principal_name: "kafka-cluster"
     )
   end
 end
diff --git a/examples/waterdrop/producer.rb b/examples/waterdrop/producer.rb
index cf04df2..fb2d0c9 100644
--- a/examples/waterdrop/producer.rb
+++ b/examples/waterdrop/producer.rb
@@ -1,22 +1,20 @@
 # frozen_string_literal: true
 
 require_relative "oauth_token_refresher"
-require 'waterdrop'
+require "waterdrop"
 
 module Producer
-
   def self.start!(kafka_config)
     @producer = WaterDrop::Producer.new do |config|
       config.deliver = true
       config.kafka = kafka_config
       # can either configure the listener or subscribe to the event
-      #config.oauth.token_provider_listener = OAuthTokenRefresher.new
+      # config.oauth.token_provider_listener = OAuthTokenRefresher.new
     end
 
-    @producer.monitor.subscribe('oauthbearer.token_refresh') do |event|
+    @producer.monitor.subscribe("oauthbearer.token_refresh") do |event|
       OAuthTokenRefresher.new.on_oauthbearer_token_refresh(event)
     end
-
   end
 
   def self.produce(**args)