diff --git a/Gemfile b/Gemfile
index 2da2279..a6756cd 100644
--- a/Gemfile
+++ b/Gemfile
@@ -11,7 +11,7 @@ gem 'fog',                     '1.38.0'
 gem 'will_paginate',           '3.1.6'
 gem 'bootstrap-will_paginate', '0.0.10'
 gem 'bootstrap-sass',          '3.3.6'
-gem 'puma',                    '3.10.0'
+gem 'puma',                    '4.3.12'
 gem 'sass-rails',              '5.0.6'
 gem 'uglifier',                '3.0.0'
 gem 'coffee-rails',            '4.2.1'
diff --git a/Gemfile.lock b/Gemfile.lock
index fb3a8f0..6830d47 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -242,7 +242,9 @@ GEM
     mime-types (3.2.2)
       mime-types-data (~> 3.2015)
     mime-types-data (3.2018.0812)
-    mimemagic (0.3.2)
+    mimemagic (0.4.3)
+      nokogiri (~> 1)
+      rake
     mini_magick (4.5.1)
     mini_mime (1.0.1)
     mini_portile2 (2.3.0)
@@ -264,7 +266,8 @@ GEM
     pry (0.11.0)
       coderay (~> 1.1.0)
       method_source (~> 0.8.1)
-    puma (3.10.0)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     rack (2.0.6)
     rack-test (0.6.3)
       rack (>= 1.0)
@@ -369,7 +372,7 @@ DEPENDENCIES
   mini_magick (= 4.5.1)
   minitest-reporters (= 1.1.9)
   pg (= 0.18.4)
-  puma (= 3.10.0)
+  puma (= 4.3.12)
   rails (= 5.0.7.1)
   rails-controller-testing (= 0.1.1)
   sass-rails (= 5.0.6)