diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index a609357..7c9a851 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -18,7 +18,7 @@ jobs:
     - name: Checkout repository
       uses: actions/checkout@v2
     - name: Checkout submodules
-      uses: textbook/git-checkout-submodule-action@master
+      uses: textbook/git-checkout-submodule-action@v2.1.1
     - name: Build
       run: cargo build --verbose
     - name: Run tests