diff --git a/Gemfile b/Gemfile
index 2af873e..085495a 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,7 +6,7 @@ gem 'rails', '~> 5.0.0'
 # Use sqlite as the database for Active Record
 gem 'sqlite3', '~> 1.3.6'
 # Use Puma as the app server
-gem 'puma', '~> 3.0'
+gem 'puma', '~> 4.3'
 # Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
 gem 'jbuilder', '~> 2.0'
 # Use Redis adapter to run Action Cable in production
diff --git a/Gemfile.lock b/Gemfile.lock
index ed3bf44..cd88ee4 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -83,7 +83,8 @@ GEM
       racc (~> 1.4)
     nokogiri (1.14.1-x86_64-linux)
       racc (~> 1.4)
-    puma (3.12.6)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     racc (1.6.2)
     rack (2.2.6.2)
     rack-test (0.6.3)
@@ -144,7 +145,7 @@ DEPENDENCIES
   byebug
   jbuilder (~> 2.0)
   listen (~> 3.0.5)
-  puma (~> 3.0)
+  puma (~> 4.3)
   rails (~> 5.0.0)
   spring
   spring-watcher-listen (~> 2.0.0)