diff --git a/.github/workflows/ruby.yml b/.github/workflows/ruby.yml
index 1b684a3..1435a43 100644
--- a/.github/workflows/ruby.yml
+++ b/.github/workflows/ruby.yml
@@ -60,6 +60,7 @@ jobs:
             rails-version: '7.2'
 
     env:
+      RUBY_VERSION: ${{ matrix.ruby-version }}
       RAILS_VERSION: ${{ matrix.rails-version }}
     steps:
     - uses: actions/checkout@v4
diff --git a/Gemfile b/Gemfile
index 26aa114..7e17fb0 100644
--- a/Gemfile
+++ b/Gemfile
@@ -10,3 +10,10 @@ if ENV['RAILS_VERSION']
 else
   gem 'rails'
 end
+
+if ENV['RUBY_VERSION'] >= '3.3'
+  gem 'mutex_m'
+  gem 'base64'
+  gem 'bigdecimal'
+  gem 'drb'
+end