diff --git a/Gemfile b/Gemfile
index 9df8c36..ebaf3d7 100644
--- a/Gemfile
+++ b/Gemfile
@@ -15,7 +15,7 @@ gem 'rails', ' ~> 5.1.6'
 gem 'pg', '~> 0.18'
 
 # Server
-gem 'puma', '~> 3.0'
+gem 'puma', '~> 3.12'
 
 # Assets
 gem 'jquery-rails'
diff --git a/Gemfile.lock b/Gemfile.lock
index caf8084..b320849 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -204,7 +204,7 @@ GEM
       pry (~> 0.10)
     psych (3.1.0)
     public_suffix (3.0.3)
-    puma (3.11.3)
+    puma (3.12.0)
     rack (2.0.6)
     rack-protection (2.0.1)
       rack
@@ -372,7 +372,7 @@ DEPENDENCIES
   nested_form_fields
   pg (~> 0.18)
   pry-byebug
-  puma (~> 3.0)
+  puma (~> 3.12)
   rails (~> 5.1.6)
   rails-controller-testing
   rspec-rails (~> 3.5)