diff --git a/Gemfile b/Gemfile
index c6f9bbf..5d91ddb 100644
--- a/Gemfile
+++ b/Gemfile
@@ -8,7 +8,7 @@ gem 'rails', '~> 6.0.0'
 # Use sqlite3 as the database for Active Record
 
 # Use Puma as the app server
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 4.3'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5'
 # Transpile app-like JavaScript. Read more: https://github.com/rails/webpacker
diff --git a/Gemfile.lock b/Gemfile.lock
index 635816c..6a78d14 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -208,7 +208,9 @@ GEM
       rack-contrib (>= 1.1, < 3)
       railties (>= 3.0.0, < 7)
     method_source (0.9.2)
-    mimemagic (0.3.3)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_mime (1.0.2)
     mini_portile2 (2.4.0)
     minitest (5.12.2)
@@ -231,7 +233,8 @@ GEM
     pry-rails (0.3.9)
       pry (>= 0.10.4)
     public_suffix (4.0.1)
-    puma (3.12.1)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     rack (2.1.2)
     rack-contrib (2.1.0)
       rack (~> 2.0)
@@ -406,7 +409,7 @@ DEPENDENCIES
   meta_request
   pg
   pry-rails
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 6.0.0)
   rails_12factor
   rspec-html-matchers