diff --git a/Gemfile b/Gemfile
index 1e834af..f19744f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -8,7 +8,7 @@ end
 ruby '2.7.2'
 gem 'rails', '~> 5.2.4'
 gem 'pg', '~> 0.18'
-gem 'puma', '~> 3.12'
+gem 'puma', '~> 4.3'
 gem 'sass-rails', '~> 5.0'
 gem 'uglifier', '>= 1.3.0'
 gem 'coffee-rails', '~> 4.2'
diff --git a/Gemfile.lock b/Gemfile.lock
index 079fa5c..e5fbe9e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -157,7 +157,8 @@ GEM
     pry-rails (0.3.9)
       pry (>= 0.10.4)
     public_suffix (4.0.6)
-    puma (3.12.6)
+    puma (4.3.11)
+      nio4r (~> 2.0)
     racc (1.5.2)
     rack (2.2.3)
     rack-proxy (0.6.5)
@@ -301,7 +302,7 @@ DEPENDENCIES
   pg (~> 0.18)
   pry-byebug
   pry-rails
-  puma (~> 3.12)
+  puma (~> 4.3)
   rails (~> 5.2.4)
   rails_12factor
   rails_layout