diff --git a/Gemfile b/Gemfile
index ea2d66c..2b40926 100644
--- a/Gemfile
+++ b/Gemfile
@@ -14,7 +14,7 @@ gem 'faraday', '~> 0.15.4'
 # json middleware for faraday
 gem 'faraday_middleware', '~> 0.13.1'
 # 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 257ef6c..ceecc73 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -82,7 +82,9 @@ GEM
     marcel (0.3.3)
       mimemagic (~> 0.3.2)
     method_source (0.9.2)
-    mimemagic (0.3.3)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_mime (1.0.2)
     mini_portile2 (2.4.0)
     minitest (5.11.3)
@@ -91,7 +93,8 @@ GEM
     nio4r (2.5.1)
     nokogiri (1.10.4)
       mini_portile2 (~> 2.4.0)
-    puma (3.12.1)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
@@ -171,7 +174,7 @@ DEPENDENCIES
   faraday (~> 0.15.4)
   faraday_middleware (~> 0.13.1)
   listen (>= 3.0.5, < 3.2)
-  puma (~> 3.11)
+  puma (~> 4.3)
   rails (~> 5.2.3)
   rspec-rails (~> 3.8, >= 3.8.2)
   spring