diff --git a/Gemfile b/Gemfile
index 5dc3042..4a8f408 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,7 +5,7 @@ ruby '2.5.1'
 
 gem 'rails', '~> 5.2.3'
 gem 'pg', '~> 0.21'
-gem 'puma', '~> 3.7'
+gem 'puma', '~> 4.3'
 gem 'bootsnap', '>= 1.1.0', require: false
 group :development do
   gem 'listen', '>= 3.0.5', '< 3.2'
diff --git a/Gemfile.lock b/Gemfile.lock
index 96480cf..fa1bc5b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -67,7 +67,9 @@ GEM
     marcel (0.3.3)
       mimemagic (~> 0.3.2)
     method_source (1.0.0)
-    mimemagic (0.3.5)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_mime (1.0.2)
     mini_portile2 (2.4.0)
     minitest (5.14.0)
@@ -76,7 +78,8 @@ GEM
     nokogiri (1.10.9)
       mini_portile2 (~> 2.4.0)
     pg (0.21.0)
-    puma (3.12.4)
+    puma (4.3.9)
+      nio4r (~> 2.0)
     rack (2.2.2)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
@@ -136,7 +139,7 @@ DEPENDENCIES
   byebug
   listen (>= 3.0.5, < 3.2)
   pg (~> 0.21)
-  puma (~> 3.7)
+  puma (~> 4.3)
   rails (~> 5.2.3)
   spring
   spring-watcher-listen (~> 2.0.0)