diff --git a/Gemfile b/Gemfile
index 1c63dbe5..e0467abd 100644
--- a/Gemfile
+++ b/Gemfile
@@ -7,7 +7,7 @@ gem 'sinatra'
 gem 'sinatra-contrib'
 
 # Use Puma as the app server
-gem 'puma', '~> 5.0'
+gem 'puma', '~> 5.6'
 
 group :development do
   gem 'better_errors'
diff --git a/Gemfile.lock b/Gemfile.lock
index 5bfdb33f..90db8296 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -58,7 +58,7 @@ GEM
     multi_json (1.15.0)
     mustermann (3.0.0)
       ruby2_keywords (~> 0.0.1)
-    nio4r (2.5.9)
+    nio4r (2.7.0)
     nokogiri (1.14.3-x86_64-darwin)
       racc (~> 1.4)
     nokogiri (1.14.3-x86_64-linux)
@@ -71,7 +71,7 @@ GEM
       coderay (~> 1.1)
       method_source (~> 1.0)
     public_suffix (5.0.1)
-    puma (5.6.5)
+    puma (5.6.8)
       nio4r (~> 2.0)
     racc (1.6.2)
     rack (2.2.7)
@@ -147,7 +147,7 @@ DEPENDENCIES
   grade_runner
   i18n
   pry
-  puma (~> 5.0)
+  puma (~> 5.6)
   rspec
   rspec-html-matchers
   sinatra