diff --git a/Rails/forum/Gemfile b/Rails/forum/Gemfile
index 992e099..ee36c82 100644
--- a/Rails/forum/Gemfile
+++ b/Rails/forum/Gemfile
@@ -14,7 +14,7 @@ gem 'rails', '~> 5.1.4'
 # Use sqlite3 as the database for Active Record
 gem 'sqlite3'
 # Use Puma as the app server
-gem 'puma', '~> 3.7'
+gem 'puma', '~> 4.3'
 # Use SCSS for stylesheets
 gem 'sass-rails', '~> 5.0'
 gem 'bootstrap-sass'
diff --git a/Rails/forum/Gemfile.lock b/Rails/forum/Gemfile.lock
index 4ef7ace..602fb12 100644
--- a/Rails/forum/Gemfile.lock
+++ b/Rails/forum/Gemfile.lock
@@ -95,7 +95,8 @@ GEM
     nokogiri (1.8.2)
       mini_portile2 (~> 2.3.0)
     orm_adapter (0.5.0)
-    puma (3.11.4)
+    puma (4.3.11)
+      nio4r (~> 2.0)
     rack (2.0.5)
     rack-test (1.0.0)
       rack (>= 1.0, < 3)
@@ -189,7 +190,7 @@ DEPENDENCIES
   jbuilder (~> 2.5)
   jquery-rails
   listen (>= 3.0.5, < 3.2)
-  puma (~> 3.7)
+  puma (~> 4.3)
   rails (~> 5.1.4)
   sass-rails (~> 5.0)
   simple_form