diff --git a/.github/workflows/gem-push.yml b/.github/workflows/gem-push.yml
index 8043a30..65773a2 100644
--- a/.github/workflows/gem-push.yml
+++ b/.github/workflows/gem-push.yml
@@ -19,7 +19,7 @@ jobs:
     - name: Set up Ruby 3.1
       uses: ruby/setup-ruby@v1
       with:
-        ruby-version: '3.1'
+        ruby-version: '4.0.0'
         bundler-cache: true # runs 'bundle install' and caches installed gems automatically
         
     - name: Generate man page
diff --git a/.tool-versions b/.tool-versions
index 3294aed..97c86d6 100644
--- a/.tool-versions
+++ b/.tool-versions
@@ -1 +1 @@
-ruby 3.3.0
+ruby 4.0.0