diff --git a/Gemfile b/Gemfile
index 63a6287..43802f6 100644
--- a/Gemfile
+++ b/Gemfile
@@ -11,7 +11,7 @@ gem 'rails', '~> 5.2.3'
 #gem 'sqlite3'
 gem 'pg'
 # 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 31ad979..d99afd7 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -76,7 +76,9 @@ 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 (1.0.1)
     mini_portile2 (2.4.0)
     minitest (5.12.2)
@@ -86,7 +88,8 @@ GEM
       mini_portile2 (~> 2.4.0)
     orm_adapter (0.5.0)
     pg (1.1.4)
-    puma (3.12.1)
+    puma (4.3.11)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-cors (1.0.5)
       rack (>= 1.6.0)
@@ -159,7 +162,7 @@ DEPENDENCIES
   jbuilder (~> 2.5)
   listen (>= 3.0.5, < 3.2)
   pg
-  puma (~> 3.11)
+  puma (~> 4.3)
   rack-cors
   rails (~> 5.2.3)
   simple_token_authentication (~> 1.0)