diff --git a/Gemfile b/Gemfile
index c4bfbaa..d0ddb32 100644
--- a/Gemfile
+++ b/Gemfile
@@ -8,7 +8,7 @@ gem 'rails', '~> 6.0.0'
 # Use mysql as the database for Active Record
 gem 'mysql2', '>= 0.4.4'
 # Use Puma as the app server
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 4.3'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5'
 # Transpile app-like JavaScript. Read more: https://github.com/rails/webpacker
diff --git a/Gemfile.lock b/Gemfile.lock
index 4a53c30..588d27f 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -203,7 +203,8 @@ GEM
     pry-rails (0.3.9)
       pry (>= 0.10.4)
     public_suffix (4.0.3)
-    puma (3.12.2)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     rack (2.1.1)
     rack-proxy (0.6.5)
       rack
@@ -348,7 +349,7 @@ DEPENDENCIES
   mini_magick
   mysql2 (>= 0.4.4)
   pry-rails
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 6.0.0)
   react-rails
   sass-rails (~> 5)