diff --git a/Gemfile b/Gemfile
index 101eb61..d5cc1ed 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,7 +5,7 @@ ruby '2.6.0'
 
 gem 'rails', '~> 5.2.3'
 gem 'pg'
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 4.3'
 gem 'sass-rails', '~> 5.0'
 gem 'uglifier', '>= 1.3.0'
 gem 'coffee-rails', '~> 4.2'
diff --git a/Gemfile.lock b/Gemfile.lock
index 067fcce..6c0ee46 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -103,7 +103,9 @@ GEM
     marcel (0.3.3)
       mimemagic (~> 0.3.2)
     method_source (0.9.2)
-    mimemagic (0.3.3)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_mime (1.0.2)
     mini_portile2 (2.4.0)
     minitest (5.11.3)
@@ -116,7 +118,8 @@ GEM
       coderay (~> 1.1.0)
       method_source (~> 0.9.0)
     public_suffix (4.0.1)
-    puma (3.12.2)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-protection (2.0.5)
       rack
@@ -239,7 +242,7 @@ DEPENDENCIES
   listen (>= 3.0.5, < 3.2)
   pg
   pry
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 5.2.3)
   rspec-rails (~> 3.8)
   sass-rails (~> 5.0)