diff --git a/Gemfile b/Gemfile
index 8ba8460..3b02ce6 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,7 +2,7 @@ source 'https://rubygems.org'
 
 gem 'rails', '5.2.3'
 gem 'pg', '~> 0.18'
-gem 'puma', '~> 3.0'
+gem 'puma', '~> 4.3'
 gem 'rack-cors'
 gem 'redis-rails'
 gem 'sucker_punch', '~> 2.0'
diff --git a/Gemfile.lock b/Gemfile.lock
index 3f0ce7b..72ad266 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -49,7 +49,7 @@ GEM
     concurrent-ruby (1.1.5)
     crass (1.0.4)
     erubi (1.8.0)
-    ffi (1.11.0)
+    ffi (1.15.5)
     globalid (0.4.2)
       activesupport (>= 4.2.0)
     i18n (1.6.0)
@@ -65,7 +65,9 @@ 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 (1.0.1)
     mini_portile2 (2.4.0)
     minitest (5.11.3)
@@ -73,7 +75,8 @@ GEM
     nokogiri (1.10.3)
       mini_portile2 (~> 2.4.0)
     pg (0.21.0)
-    puma (3.12.1)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-cors (1.0.3)
     rack-test (1.1.0)
@@ -154,7 +157,7 @@ DEPENDENCIES
   chipmunk (~> 6.1, >= 6.1.3.4)
   listen (~> 3.0.5)
   pg (~> 0.18)
-  puma (~> 3.0)
+  puma (~> 4.3)
   rack-cors
   rails (= 5.2.3)
   redis-rails