diff --git a/Gemfile b/Gemfile
index e22375d5..8ec55523 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,7 +6,7 @@ gem 'rails', '~> 5.2.2'
 # Use postgresql as the database for Active Record
 gem 'pg', '>= 0.18', '< 2.0'
 # Use Puma as the app server
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 4.3'
 # Reduces boot times through caching; required in config/boot.rb
 gem 'bootsnap', '>= 1.1.0', require: false
 # Authentication
diff --git a/Gemfile.lock b/Gemfile.lock
index de095bff..f23df137 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -98,7 +98,8 @@ GEM
     pry (0.12.2)
       coderay (~> 1.1.0)
       method_source (~> 0.9.0)
-    puma (3.12.1)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
@@ -165,7 +166,7 @@ DEPENDENCIES
   listen (>= 3.0.5, < 3.2)
   pg (>= 0.18, < 2.0)
   pry
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 5.2.2)
   spring
   spring-watcher-listen (~> 2.0.0)