diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6fd3c14..9ace1ee 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,8 +20,8 @@ jobs:
       matrix:
         ruby: ['3.1', '3.2', '3.3', '3.4', '4.0']
     steps:
-      - uses: actions/checkout@v6
-      - uses: ruby/setup-ruby@v1
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - uses: ruby/setup-ruby@c4e5b1316158f92e3d49443a9d58b31d25ac0f8f # v1.306.0
         with:
           ruby-version: ${{ matrix.ruby }}
           bundler: '2.6.9'