diff --git a/examples/rails-custom-login-page/Gemfile b/examples/rails-custom-login-page/Gemfile
index 605873c..304584d 100644
--- a/examples/rails-custom-login-page/Gemfile
+++ b/examples/rails-custom-login-page/Gemfile
@@ -11,7 +11,7 @@ gem 'rails', '~> 5.1.4'
 # Use sqlite3 as the database for Active Record
 gem 'sqlite3'
 # Use Puma as the app server
-gem 'puma', '~> 3.12'
+gem 'puma', '~> 4.3'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5.0'
 # Use Uglifier as compressor for JavaScript assets
diff --git a/examples/rails-custom-login-page/Gemfile.lock b/examples/rails-custom-login-page/Gemfile.lock
index 63670f8..2b6b7a7 100644
--- a/examples/rails-custom-login-page/Gemfile.lock
+++ b/examples/rails-custom-login-page/Gemfile.lock
@@ -104,7 +104,8 @@ GEM
       httparty (>= 0.13.7)
       nokogiri (>= 1.6.3.1)
     public_suffix (3.0.2)
-    puma (3.12.2)
+    puma (4.3.8)
+      nio4r (~> 2.0)
     rack (2.0.8)
     rack-test (0.8.3)
       rack (>= 1.0, < 3)
@@ -196,7 +197,7 @@ DEPENDENCIES
   jquery-rails
   listen (>= 3.0.5, < 3.2)
   onelogin (~> 1.5.0)
-  puma (~> 3.12)
+  puma (~> 4.3)
   rails (~> 5.1.4)
   sass-rails (~> 5.0)
   selenium-webdriver