diff --git a/.github/workflows/build_dependencies.yml b/.github/workflows/build_dependencies.yml
index a3d0348..4d5ced3 100644
--- a/.github/workflows/build_dependencies.yml
+++ b/.github/workflows/build_dependencies.yml
@@ -91,10 +91,33 @@ jobs:
   BuildHomeBlocksDeps:
     runs-on: ${{ inputs.platform }}
     steps:
+    - name: Resolve checkout ref
+      id: resolve-ref
+      shell: bash
+      run: |
+        requested_ref="${{ inputs.branch }}"
+        fallback_ref="${{ github.ref }}"
+        repo_url="${{ github.server_url }}/${{ github.repository }}"
+
+        if [[ -z "${requested_ref}" ]]; then
+          echo "::warning::No branch/ref was provided; falling back to '${fallback_ref}'."
+          checkout_ref="${fallback_ref}"
+        elif [[ "${requested_ref}" =~ ^refs/ ]] && git check-ref-format "${requested_ref}"; then
+          checkout_ref="${requested_ref}"
+        elif git check-ref-format "refs/heads/${requested_ref}" && \
+             git ls-remote --exit-code --heads "${repo_url}" "${requested_ref}" >/dev/null 2>&1; then
+          checkout_ref="${requested_ref}"
+        else
+          echo "::warning::Requested branch/ref '${requested_ref}' is invalid or was not found in ${{ github.repository }}; falling back to '${fallback_ref}'."
+          checkout_ref="${fallback_ref}"
+        fi
+
+        echo "checkout_ref=${checkout_ref}" >> "${GITHUB_OUTPUT}"
+
     - name: Retrieve Code
       uses: actions/checkout@v4
       with:
-        ref: ${{ inputs.branch }}
+        ref: ${{ steps.resolve-ref.outputs.checkout_ref }}
       if: ${{ inputs.testing == 'True' }}
 
     - name: Check Code Formatting
@@ -132,7 +155,7 @@ jobs:
       uses: actions/checkout@v4
       with:
         repository: eBay/HomeBlocks
-        ref: ${{ inputs.branch }}
+        ref: ${{ steps.resolve-ref.outputs.checkout_ref }}
       if: ${{ inputs.testing == 'False' }}
 
     - name: Setup Conan