diff --git a/Gemfile b/Gemfile
index ec2d0f2..156bf23 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,7 +6,7 @@ git_source(:github) do |repo_name|
 end
 
 gem 'rails', '~> 5.1.1'
-gem 'puma', '~> 3.7'
+gem 'puma', '~> 4.3'
 gem 'pg'
 gem 'active_model_serializers', '~> 0.10.0'
 gem 'responders'
diff --git a/Gemfile.lock b/Gemfile.lock
index de17543..87b518a 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -101,7 +101,8 @@ GEM
     pry-rails (0.3.9)
       pry (>= 0.10.4)
     public_suffix (4.0.6)
-    puma (3.12.6)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     pundit (2.1.0)
       activesupport (>= 3.0.0)
     racc (1.5.2)
@@ -211,7 +212,7 @@ DEPENDENCIES
   listen (>= 3.0.5, < 3.2)
   pg
   pry-rails
-  puma (~> 3.7)
+  puma (~> 4.3)
   pundit
   rails (~> 5.1.1)
   responders