diff --git a/Gemfile b/Gemfile
index cfc433c..4ad041c 100644
--- a/Gemfile
+++ b/Gemfile
@@ -10,7 +10,7 @@ gem 'rails', '~> 5.2.1'
 # Use postgresql as the database for Active Record
 gem 'pg', '>= 0.18', '< 2.0'
 # Use Puma as the app server
-gem 'puma', '~> 3.11'
+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 141b490..bb690bc 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -107,16 +107,16 @@ GEM
       public_suffix (>= 2.0.2, < 5.0)
     arel (9.0.0)
     aws-eventstream (1.1.0)
-    aws-partitions (1.328.0)
-    aws-sdk-core (3.99.0)
+    aws-partitions (1.329.0)
+    aws-sdk-core (3.99.2)
       aws-eventstream (~> 1, >= 1.0.2)
       aws-partitions (~> 1, >= 1.239.0)
       aws-sigv4 (~> 1.1)
       jmespath (~> 1.0)
-    aws-sdk-kms (1.34.0)
-      aws-sdk-core (~> 3, >= 3.71.0)
+    aws-sdk-kms (1.34.1)
+      aws-sdk-core (~> 3, >= 3.99.0)
       aws-sigv4 (~> 1.1)
-    aws-sdk-s3 (1.68.0)
+    aws-sdk-s3 (1.68.1)
       aws-sdk-core (~> 3, >= 3.99.0)
       aws-sdk-kms (~> 1)
       aws-sigv4 (~> 1.1)
@@ -302,7 +302,8 @@ GEM
     pry-rails (0.3.9)
       pry (>= 0.10.4)
     public_suffix (4.0.5)
-    puma (3.12.0)
+    puma (4.3.5)
+      nio4r (~> 2.0)
     pundit (1.1.0)
       activesupport (>= 3.0.0)
     rack (2.2.2)
@@ -430,7 +431,7 @@ DEPENDENCIES
   listen (>= 3.0.5, < 3.2)
   pg (>= 0.18, < 2.0)
   pry-rails
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 5.2.1)
   sass-rails (~> 5.0)
   spring