diff --git a/Gemfile b/Gemfile
index 98bc56e..0520ac4 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,7 +6,7 @@ ruby '2.6.2'
 gem 'rails', '~> 5.2.3'
 gem 'redis', '~> 4.0'
 gem 'pg'
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 4.3'
 gem 'sass', require: false
 gem 'sass-rails', '~> 5.0'
 gem 'uglifier', '>= 1.3.0'
diff --git a/Gemfile.lock b/Gemfile.lock
index 788b2da..78baea2 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -108,7 +108,9 @@ 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 (5.12.2)
@@ -126,7 +128,8 @@ GEM
       byebug (~> 11.0)
       pry (~> 0.10)
     public_suffix (4.0.1)
-    puma (3.12.1)
+    puma (4.3.9)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
@@ -256,7 +259,7 @@ DEPENDENCIES
   listen (>= 3.0.5, < 3.2)
   pg
   pry-byebug (~> 3.4)
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 5.2.3)
   redis (~> 4.0)
   rspec-rails