diff --git a/Gemfile b/Gemfile
index 022150b..74b3c10 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,7 +5,7 @@ ruby '2.7.2'
 
 gem 'rails', '~> 5.2.0'
 gem 'pg'
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 4.3'
 gem 'sass-rails', '~> 5.0'
 gem 'uglifier', '>= 1.3.0'
 
diff --git a/Gemfile.lock b/Gemfile.lock
index d43e07a..5f2602e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -138,7 +138,8 @@ GEM
       coderay (~> 1.1)
       method_source (~> 1.0)
     public_suffix (4.0.6)
-    puma (3.12.6)
+    puma (4.3.9)
+      nio4r (~> 2.0)
     racc (1.5.2)
     rack (2.2.3)
     rack-test (1.1.0)
@@ -276,7 +277,7 @@ DEPENDENCIES
   mimemagic (~> 0.3.6)
   pg
   pry
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 5.2.0)
   rails-controller-testing
   rspec-rails