diff --git a/Gemfile b/Gemfile
index c562a15..69d417f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -23,7 +23,7 @@ gem 'carrierwave', '~> 1.0'
 gem 'rmagick', '~> 2.16'
 gem 'fog-aws', '~> 1.4.1'
 
-gem 'puma', '~> 3.7'
+gem 'puma', '~> 4.3'
 
 group :development, :test do
   gem 'sqlite3'
diff --git a/Gemfile.lock b/Gemfile.lock
index ced7214..7948f44 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -197,8 +197,10 @@ GEM
     pg (1.2.3-x64-mingw32)
     pg (1.2.3-x86-mingw32)
     public_suffix (4.0.6)
-    puma (3.12.6)
-    puma (3.12.6-java)
+    puma (4.3.12)
+      nio4r (~> 2.0)
+    puma (4.3.12-java)
+      nio4r (~> 2.0)
     raabro (1.4.0)
     rack (2.2.3)
     rack-protection (2.1.0)
@@ -361,7 +363,7 @@ DEPENDENCIES
   letter_opener
   listen (>= 3.0.5, < 3.2)
   pg
-  puma (~> 3.7)
+  puma (~> 4.3)
   rails (~> 5.2.4)
   rails-i18n (~> 5.1)
   resque (~> 1.27)