diff --git a/Gemfile b/Gemfile
index 6fbd214..184fc22 100644
--- a/Gemfile
+++ b/Gemfile
@@ -16,7 +16,7 @@ gem 'rails-i18n', '~> 5.1'
 # Use postgresql as the database for Active Record
 gem 'pg', '>= 0.18', '< 2.0'
 # Use Puma as the app server
-gem 'puma', '~> 3.12'
+gem 'puma', '~> 4.3'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5.0'
 # Use Uglifier as compressor for JavaScript assets
diff --git a/Gemfile.lock b/Gemfile.lock
index 0e31b7c..9126e5e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -169,7 +169,9 @@ GEM
     mime-types (3.2.2)
       mime-types-data (~> 3.2015)
     mime-types-data (3.2019.0331)
-    mimemagic (0.3.3)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_magick (4.9.5)
     mini_mime (1.0.1)
     mini_portile2 (2.4.0)
@@ -183,7 +185,8 @@ GEM
     orm_adapter (0.5.0)
     pg (1.1.4)
     public_suffix (3.0.3)
-    puma (3.12.6)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     rack (2.2.3)
     rack-pjax (1.1.0)
       nokogiri (~> 1.5)
@@ -308,7 +311,7 @@ DEPENDENCIES
   listen (>= 3.0.5, < 3.2)
   mini_magick
   pg (>= 0.18, < 2.0)
-  puma (~> 3.12)
+  puma (~> 4.3)
   rails (~> 5.2.3)
   rails-i18n (~> 5.1)
   rails_admin