diff --git a/Gemfile b/Gemfile
index 6dd5a6f..83c7cb0 100644
--- a/Gemfile
+++ b/Gemfile
@@ -7,7 +7,7 @@ ruby '2.5.0'
 gem 'rails', '~> 5.2.1'
 
 # Use Puma as the app server
-gem 'puma', '~> 3.11'
+gem 'puma', '~> 4.3'
 # Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
 # gem 'jbuilder', '~> 2.5'
 # Use Redis adapter to run Action Cable in production
diff --git a/Gemfile.lock b/Gemfile.lock
index 13df4ae..d665601 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -67,7 +67,9 @@ GEM
     marcel (0.3.3)
       mimemagic (~> 0.3.2)
     method_source (0.9.0)
-    mimemagic (0.3.2)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_mime (1.0.1)
     mini_portile2 (2.3.0)
     minitest (5.11.3)
@@ -76,7 +78,8 @@ GEM
     nokogiri (1.8.5)
       mini_portile2 (~> 2.3.0)
     pg (1.1.3)
-    puma (3.12.0)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     rack (2.0.5)
     rack-cors (1.0.2)
     rack-test (1.1.0)
@@ -139,7 +142,7 @@ DEPENDENCIES
   byebug
   listen (>= 3.0.5, < 3.2)
   pg
-  puma (~> 3.11)
+  puma (~> 4.3)
   rack-cors
   rails (~> 5.2.1)
   spring