diff --git a/Gemfile b/Gemfile
index 1eae430..8ab1fcd 100644
--- a/Gemfile
+++ b/Gemfile
@@ -4,7 +4,7 @@ source 'https://rubygems.org'
 # Rails, MySQL, Puma
 gem 'rails', '~> 5.2.0'
 gem 'mysql2', '>= 0.4.4', '< 0.6.0'
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 4.3'
 
 # Rails Dependencies
 gem 'sass-rails', '~> 5.0'
diff --git a/Gemfile.lock b/Gemfile.lock
index 6e88737..d24863b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -122,7 +122,8 @@ GEM
     nokogiri (1.11.3)
       mini_portile2 (~> 2.5.0)
       racc (~> 1.4)
-    puma (3.12.4)
+    puma (4.3.9)
+      nio4r (~> 2.0)
     racc (1.5.2)
     rack (2.2.3)
     rack-test (1.1.0)
@@ -230,7 +231,7 @@ DEPENDENCIES
   mime-types
   mini_magick
   mysql2 (>= 0.4.4, < 0.6.0)
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 5.2.0)
   rmagick
   sass-rails (~> 5.0)