diff --git a/Gemfile b/Gemfile
index 5dc0309e..2253834f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -10,7 +10,7 @@ gem 'rails', '~> 6.0'
 # 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'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5.0'
 # Use Uglifier as compressor for JavaScript assets
diff --git a/Gemfile.lock b/Gemfile.lock
index f8c1eb10..c5f84ccd 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -7,8 +7,12 @@ GIT
       i18n (>= 1.6, < 1.8)
 
 GEM
-  remote: https://rubygems.org/
   remote: https://rails-assets.org/
+  specs:
+    rails-assets-bulma (0.7.4)
+
+GEM
+  remote: https://rubygems.org/
   specs:
     aasm (5.0.6)
       concurrent-ruby (~> 1.0)
@@ -246,7 +250,8 @@ GEM
       byebug (~> 11.0)
       pry (~> 0.10)
     public_suffix (4.0.1)
-    puma (3.12.1)
+    puma (4.3.9)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-proxy (0.6.5)
       rack
@@ -267,7 +272,6 @@ GEM
       bundler (>= 1.3.0)
       railties (= 6.0.0)
       sprockets-rails (>= 2.0.0)
-    rails-assets-bulma (0.7.4)
     rails-controller-testing (1.0.4)
       actionpack (>= 5.0.1.x)
       actionview (>= 5.0.1.x)
@@ -423,7 +427,7 @@ DEPENDENCIES
   pg (>= 0.18, < 2.0)
   pry
   pry-byebug
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 6.0)
   rails-assets-bulma!
   rails-controller-testing