diff --git a/examples/simple_rails_api/Gemfile b/examples/simple_rails_api/Gemfile
index 8f98992..3fab5da 100644
--- a/examples/simple_rails_api/Gemfile
+++ b/examples/simple_rails_api/Gemfile
@@ -6,7 +6,7 @@ gem 'rails', '~> 6.0.2'
 # Use sqlite3 as the database for Active Record
 gem 'sqlite3', '~> 1.4'
 # Use Puma as the app server
-gem 'puma', '~> 4.1'
+gem 'puma', '~> 4.3'
 # Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
 # gem 'jbuilder', '~> 2.7'
 # Use Redis adapter to run Action Cable in production
diff --git a/examples/simple_rails_api/Gemfile.lock b/examples/simple_rails_api/Gemfile.lock
index c89e612..7120c3a 100644
--- a/examples/simple_rails_api/Gemfile.lock
+++ b/examples/simple_rails_api/Gemfile.lock
@@ -88,7 +88,7 @@ GEM
     nio4r (2.5.2)
     nokogiri (1.10.8)
       mini_portile2 (~> 2.4.0)
-    puma (4.3.1)
+    puma (4.3.3)
       nio4r (~> 2.0)
     rack (2.2.2)
     rack-test (1.1.0)
@@ -152,7 +152,7 @@ DEPENDENCIES
   bootsnap (>= 1.4.2)
   byebug
   listen (>= 3.0.5, < 3.2)
-  puma (~> 4.1)
+  puma (~> 4.3)
   rails (~> 6.0.2)
   spring
   spring-watcher-listen (~> 2.0.0)