diff --git a/Gemfile b/Gemfile
index fbfa62c..86721c3 100644
--- a/Gemfile
+++ b/Gemfile
@@ -14,7 +14,7 @@ gem 'rails', '~> 5.2.3'
 # Use postgresql as the database for Active Record
 gem 'pg', '>= 0.18', '< 2.0'
 # Use Puma as the app server
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 4.3'
 gem 'google-id-token'
 gem 'google-api-client', '~> 0.11'
 # Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
diff --git a/Gemfile.lock b/Gemfile.lock
index 4701998..f43d5f1 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -124,7 +124,8 @@ GEM
     os (1.0.1)
     pg (1.1.4)
     public_suffix (3.1.0)
-    puma (3.12.1)
+    puma (4.3.11)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-cors (1.0.2)
     rack-proxy (0.6.5)
@@ -216,7 +217,7 @@ DEPENDENCIES
   listen (>= 3.0.5, < 3.2)
   nokogiri
   pg (>= 0.18, < 2.0)
-  puma (~> 3.11)
+  puma (~> 4.3)
   rack-cors
   rails (~> 5.2.3)
   ransack