diff --git a/Gemfile b/Gemfile
index da6bce7..9be940b 100644
--- a/Gemfile
+++ b/Gemfile
@@ -12,7 +12,7 @@ gem 'rails', '~> 5.2.4'
 # Use postgresql as the database for Active Record
 gem 'pg', '~> 0.18'
 # Use Puma as the app server
-gem 'puma', '3.12.6'
+gem 'puma', '4.3.11'
 gem 'rack-timeout'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5.0'
diff --git a/Gemfile.lock b/Gemfile.lock
index b87826c..4375b4f 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -161,7 +161,8 @@ GEM
       activesupport (>= 5.0, < 7.0)
     pg (0.21.0)
     public_suffix (4.0.6)
-    puma (3.12.6)
+    puma (4.3.11)
+      nio4r (~> 2.0)
     pundit (2.1.0)
       activesupport (>= 3.0.0)
     rack (2.2.3)
@@ -310,7 +311,7 @@ DEPENDENCIES
   money-rails
   order_query
   pg (~> 0.18)
-  puma (= 3.12.6)
+  puma (= 4.3.11)
   pundit
   rack-timeout
   rails (~> 5.2.4)