diff --git a/Gemfile b/Gemfile
index 2263071..0ea2bc4 100644
--- a/Gemfile
+++ b/Gemfile
@@ -28,7 +28,7 @@ gem 'polylines', '~> 0.3.0'
 gem 'simplify_rb', '~> 0.3.0'
 gem 'jquery-minicolors-rails', '~> 2.2.3.1'
 gem 'font-awesome-rails', '~> 4.7.0.2'
-gem 'puma', '~> 3.10.0'
+gem 'puma', '~> 4.3.11'
 gem 'rails-controller-testing', '~> 1.0.2'
 gem 'lograge', '~> 0.6.0'
 
diff --git a/Gemfile.lock b/Gemfile.lock
index 36e28ef..cf3e671 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -181,7 +181,8 @@ GEM
       slop (~> 3.4)
     pry-rails (0.3.6)
       pry (>= 0.10.4)
-    puma (3.10.0)
+    puma (4.3.11)
+      nio4r (~> 2.0)
     pundit (1.1.0)
       activesupport (>= 3.0.0)
     rack (2.2.2)
@@ -315,7 +316,7 @@ DEPENDENCIES
   pg (~> 0.21.0)
   polylines (~> 0.3.0)
   pry-rails (~> 0.3.6)
-  puma (~> 3.10.0)
+  puma (~> 4.3.11)
   pundit (~> 1.1.0)
   rack-timeout (~> 0.4.2)
   rails (~> 5.1.7)