diff --git a/Gemfile b/Gemfile
index be14690..bcfb5a7 100644
--- a/Gemfile
+++ b/Gemfile
@@ -8,7 +8,7 @@ end
 ruby '2.6.3'
 
 gem 'rails', '~> 6.0.0'
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 4.3'
 gem 'sass-rails', '~> 5'
 gem 'uglifier', '>= 1.3.0'
 gem 'coffee-rails', '~> 5.0.0'
diff --git a/Gemfile.lock b/Gemfile.lock
index 164b653..31dab4b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -122,7 +122,8 @@ GEM
       mini_portile2 (~> 2.4.0)
     orm_adapter (0.5.0)
     pg (1.1.4)
-    puma (3.12.1)
+    puma (4.3.9)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
@@ -223,7 +224,7 @@ DEPENDENCIES
   jquery-rails
   listen (>= 3.0.5, < 3.2)
   pg
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 6.0.0)
   rails_layout
   sass-rails (~> 5)