diff --git a/Gemfile b/Gemfile
index 323f145..844bc62 100644
--- a/Gemfile
+++ b/Gemfile
@@ -9,7 +9,7 @@ gem 'pry'
 # Use pg as the database for Active Record
 gem 'pg'
 # Use Puma as the app server
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 4.3'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5.0'
 # Use Uglifier as compressor for JavaScript assets
diff --git a/Gemfile.lock b/Gemfile.lock
index ea85048..e7a8ce8 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -179,7 +179,8 @@ GEM
       coderay (~> 1.1)
       method_source (~> 1.0)
     public_suffix (4.0.6)
-    puma (3.12.6)
+    puma (4.3.11)
+      nio4r (~> 2.0)
     pundit (2.1.0)
       activesupport (>= 3.0.0)
     pundit-matchers (1.6.0)
@@ -320,7 +321,7 @@ DEPENDENCIES
   pg
   popper_js (~> 1.14.5)
   pry
-  puma (~> 3.11)
+  puma (~> 4.3)
   pundit (~> 2.0)
   pundit-matchers (~> 1.6.0)
   rails (~> 5.2.2)