diff --git a/Gemfile b/Gemfile
index e4f36d9..b9f85ca 100644
--- a/Gemfile
+++ b/Gemfile
@@ -13,7 +13,7 @@ gem 'devise-jwt'
 gem 'dotenv-rails', require: 'dotenv/rails-now'
 gem 'dry-configurable', '0.9.0' # pin version because later version conflicts with devise-jwt
 gem 'pg'
-gem 'puma', '~> 3.12' # app server
+gem 'puma', '~> 5.6' # app server
 gem 'rack-cors', require: 'rack/cors'
 gem 'rails', '~> 6.0.3'
 gem 'warden-jwt_auth', '~> 0.4.2'
diff --git a/Gemfile.lock b/Gemfile.lock
index 0883ce5..6e13416 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -63,6 +63,8 @@ GEM
     bcrypt (3.1.16-java)
     bootsnap (1.5.1)
       msgpack (~> 1.0)
+    bootsnap (1.5.1-java)
+      msgpack (~> 1.0)
     builder (3.2.4)
     bundle-audit (0.1.0)
       bundler-audit
@@ -83,12 +85,12 @@ GEM
     capistrano-rvm (0.1.2)
       capistrano (~> 3.0)
       sshkit (~> 1.2)
-    capistrano3-puma (3.1.1)
+    capistrano3-puma (5.2.0)
       capistrano (~> 3.7)
       capistrano-bundler
-      puma (~> 3.4)
+      puma (>= 4.0, < 6.0)
     coderay (1.1.3)
-    concurrent-ruby (1.1.7)
+    concurrent-ruby (1.1.10)
     config (2.2.1)
       deep_merge (~> 1.2, >= 1.2.1)
       dry-validation (~> 1.0, >= 1.0.0)
@@ -171,7 +173,7 @@ GEM
     http-accept (1.7.0)
     http-cookie (1.0.3)
       domain_name (~> 0.5)
-    i18n (1.8.5)
+    i18n (1.10.0)
       concurrent-ruby (~> 1.0)
     jwt (2.2.2)
     listen (3.1.5)
@@ -217,8 +219,10 @@ GEM
       coderay (~> 1.1)
       method_source (~> 1.0)
       spoon (~> 0.0)
-    puma (3.12.6)
-    puma (3.12.6-java)
+    puma (5.6.4)
+      nio4r (~> 2.0)
+    puma (5.6.4-java)
+      nio4r (~> 2.0)
     rack (2.2.3)
     rack-cors (1.1.1)
       rack (>= 2.0.0)
@@ -251,7 +255,7 @@ GEM
       rake (>= 0.8.7)
       thor (>= 0.20.3, < 2.0)
     rainbow (3.0.0)
-    rake (13.0.1)
+    rake (13.0.6)
     rb-fsevent (0.10.4)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
@@ -331,7 +335,7 @@ GEM
       actionpack (>= 4.0)
       activesupport (>= 4.0)
       sprockets (>= 3.0.0)
-    sshkit (1.21.0)
+    sshkit (1.21.2)
       net-scp (>= 1.1.2)
       net-ssh (>= 2.8.0)
     sync (0.5.0)
@@ -389,7 +393,7 @@ DEPENDENCIES
   listen (>= 3.0.5, < 3.2)
   pg
   pry
-  puma (~> 3.12)
+  puma (~> 5.6)
   rack-cors
   rails (~> 6.0.3)
   rspec-rails