diff --git a/Gemfile b/Gemfile
index f04df62..e992d18 100644
--- a/Gemfile
+++ b/Gemfile
@@ -7,7 +7,7 @@ gem "autoprefixer-rails"
 gem "rack-canonical-host"
 gem "passwordless"
 gem "pg", ">= 0.18", "< 2.0"
-gem "puma", "~> 3.11"
+gem "puma", "~> 4.3"
 gem "rails", "~> 5.2.3"
 gem "sass-rails", "~> 5.0"
 gem "tailwindcss", "~> 1.0.0"
diff --git a/Gemfile.lock b/Gemfile.lock
index c401caf..b9d0ff3 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -132,7 +132,9 @@ GEM
     marcel (0.3.3)
       mimemagic (~> 0.3.2)
     method_source (0.9.2)
-    mimemagic (0.3.3)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
     mini_mime (1.0.2)
     mini_portile2 (2.4.0)
     minitest (5.11.3)
@@ -151,7 +153,8 @@ GEM
     pry-rails (0.3.6)
       pry (>= 0.10.4)
     public_suffix (3.0.2)
-    puma (3.12.0)
+    puma (4.3.9)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-canonical-host (0.2.3)
       addressable (> 0, < 3)
@@ -315,7 +318,7 @@ DEPENDENCIES
   passwordless
   pg (>= 0.18, < 2.0)
   pry-rails
-  puma (~> 3.11)
+  puma (~> 4.3)
   rack-canonical-host
   rack-timeout
   rails (~> 5.2.3)