diff --git a/Gemfile b/Gemfile
old mode 100755
new mode 100644
index fa79c8f..6f70941
--- a/Gemfile
+++ b/Gemfile
@@ -7,7 +7,7 @@ ruby '2.5.3'
 gem 'rails', '~> 5.2.0'
 
 # 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 021d5b4..0eadcee 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -100,7 +100,9 @@ GEM
     marcel (0.3.3)
       mimemagic (~> 0.3.2)
     method_source (1.0.0)
-    mimemagic (0.3.6)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_mime (1.0.2)
     mini_portile2 (2.5.0)
     minitest (5.14.4)
@@ -111,7 +113,8 @@ GEM
       racc (~> 1.4)
     pg (1.2.3)
     public_suffix (4.0.6)
-    puma (3.12.6)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     racc (1.5.2)
     rack (2.2.3)
     rack-test (1.1.0)
@@ -231,7 +234,7 @@ DEPENDENCIES
   jbuilder (~> 2.5)
   listen (>= 3.0.5, < 3.2)
   pg
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 5.2.0)
   rails-controller-testing
   rspec-rails (~> 3.7)