diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index dc3745b..fcaa7e0 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -16,13 +16,13 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [ "2.0.0", 2.1, 2.3, 2.4, 2.5, 2.6, 2.7, "3.0", 3.1, 3.2, jruby-9.1, jruby-9.2, jruby-9.3, jruby-9.4 ]
+        ruby: [ "2.0.0", 2.1, 2.3, 2.4, 2.5, 2.6, 2.7, "3.0", 3.1, 3.2, 3.3, jruby-9.1, jruby-9.2, jruby-9.3, jruby-9.4 ]
     name: ${{ matrix.ruby }}
     env:
       BUNDLE_GEMFILE: .ci.gemfile
       COFFEE_SCRIPT: use
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     # WikiCloth needs IDN
     # Pandoc needs Pandoc
     - run: sudo apt-get install -y libidn11-dev pandoc