diff --git a/Gemfile b/Gemfile
index 029d630..3b31170 100644
--- a/Gemfile
+++ b/Gemfile
@@ -12,7 +12,7 @@ gem 'rails', '~> 6.0.2.1'
 # Use postgresql as the database for Active Record
 gem 'pg', '>= 0.18', '< 2.0'
 # Use Puma as the app server
-gem 'puma', '~> 3.0'
+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 a227933..536e6ab 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -106,7 +106,9 @@ GEM
     marcel (0.3.3)
       mimemagic (~> 0.3.2)
     method_source (0.9.2)
-    mimemagic (0.3.4)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_mime (1.0.2)
     mini_portile2 (2.4.0)
     minitest (5.14.0)
@@ -115,7 +117,8 @@ GEM
       mini_portile2 (~> 2.4.0)
     pg (1.2.2)
     public_suffix (4.0.3)
-    puma (3.12.2)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     rack (2.2.2)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
@@ -224,7 +227,7 @@ DEPENDENCIES
   jquery-rails
   listen (~> 3.0.5)
   pg (>= 0.18, < 2.0)
-  puma (~> 3.0)
+  puma (~> 4.3)
   rails (~> 6.0.2.1)
   rspec-rails
   sass-rails (~> 5.0)