diff --git a/Gemfile b/Gemfile
index 956c5b2..203a4e0 100644
--- a/Gemfile
+++ b/Gemfile
@@ -9,7 +9,7 @@ gem 'rake'
 
 # http layer
 gem 'hanami', '1.3.0'
-gem 'puma', '~> 3.12.4'
+gem 'puma', '~> 4.3.12'
 gem 'xml-sitemap'
 
 # persistance layer
diff --git a/Gemfile.lock b/Gemfile.lock
index 785d072..675faf2 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -271,6 +271,7 @@ GEM
     mutant-rspec (0.9.10)
       mutant (~> 0.9.10)
       rspec-core (>= 3.8.0, < 4.0.0)
+    nio4r (2.5.8)
     nokogiri (1.10.10)
       mini_portile2 (~> 2.4.0)
     oauth2 (1.4.4)
@@ -291,7 +292,8 @@ GEM
     pg (1.2.3)
     procto (0.0.3)
     public_suffix (4.0.6)
-    puma (3.12.6)
+    puma (4.3.12)
+      nio4r (~> 2.0)
     raabro (1.3.1)
     rack (2.2.3)
     rack-protection (2.1.0)
@@ -464,7 +466,7 @@ DEPENDENCIES
   omniauth
   omniauth-github!
   pg
-  puma (~> 3.12.4)
+  puma (~> 4.3.12)
   rake
   relative_time!
   rinku