diff --git a/Gemfile b/Gemfile
index c18abcb..03c6bc2 100644
--- a/Gemfile
+++ b/Gemfile
@@ -12,7 +12,7 @@ gem 'coffee-rails', '~> 4.2'
 gem 'dotenv-rails'
 gem 'nokogiri'
 gem 'pg'
-gem 'puma', '~> 3.7'
+gem 'puma', '~> 4.3'
 gem 'rails', '~> 5.1.1'
 gem 'ransack', github: 'activerecord-hackery/ransack'
 gem 'redis'
diff --git a/Gemfile.lock b/Gemfile.lock
index 606d684..6c2cfd8 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -130,7 +130,8 @@ GEM
       activerecord (>= 3.0)
     powerpack (0.1.1)
     public_suffix (2.0.5)
-    puma (3.9.1)
+    puma (4.3.11)
+      nio4r (~> 2.0)
     rack (2.0.3)
     rack-protection (2.0.0)
       rack
@@ -263,7 +264,7 @@ DEPENDENCIES
   listen (>= 3.0.5, < 3.2)
   nokogiri
   pg
-  puma (~> 3.7)
+  puma (~> 4.3)
   rails (~> 5.1.1)
   ransack!
   redis