diff --git a/Gemfile b/Gemfile
index 64f190e..03d5f0b 100644
--- a/Gemfile
+++ b/Gemfile
@@ -11,7 +11,7 @@ group :development, :test do
   gem 'rspec-rails'
 end
 # 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 a0dab24..ae1ef73 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -118,7 +118,8 @@ GEM
       mini_portile2 (~> 2.4.0)
     pg (1.1.4)
     public_suffix (4.0.1)
-    puma (3.12.1)
+    puma (4.3.11)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-proxy (0.6.5)
       rack
@@ -247,7 +248,7 @@ DEPENDENCIES
   jquery-rails
   listen (>= 3.0.5, < 3.2)
   pg
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 6.0.0)
   rails_12factor
   rspec-rails