diff --git a/Gemfile b/Gemfile
index de55688..f65918f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -20,7 +20,7 @@ gem 'pg', '~> 0.18.4'
 # Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
 gem 'rails', '~> 6.0'
 # Use Puma as the app server
-gem 'puma', '~> 3.7'
+gem 'puma', '~> 4.3'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 6.0'
 # Use Uglifier as compressor for JavaScript assets
diff --git a/Gemfile.lock b/Gemfile.lock
index 8ae21e5..3ac4ad8 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -130,7 +130,8 @@ GEM
     parser (2.7.2.0)
       ast (~> 2.4.1)
     pg (0.18.4)
-    puma (3.12.6)
+    puma (4.3.11)
+      nio4r (~> 2.0)
     rack (2.2.3)
     rack-cors (1.1.1)
       rack (>= 2.0.0)
@@ -268,7 +269,7 @@ DEPENDENCIES
   listen (>= 3.0.5, < 3.2)
   overcommit
   pg (~> 0.18.4)
-  puma (~> 3.7)
+  puma (~> 4.3)
   rack-cors
   rails (~> 6.0)
   rspec-rails