diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 75f4c29..d60de14 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -14,7 +14,7 @@ jobs:
     name: Build and test
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7
 
       - name: Install devcontainer CLI
         run: npm install -g @devcontainers/cli@0