diff --git a/.github/workflows/render.yml b/.github/workflows/render.yml
index 8be757b0d..81b520af6 100644
--- a/.github/workflows/render.yml
+++ b/.github/workflows/render.yml
@@ -10,5 +10,9 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4.1.7
 
+      - name: Verify nonexistence of `rendered`
+        shell: bash
+        run: if [ -e rendered ]; then exit 1; fi
+
       - name: Compile ZIPs and Zcash Protocol Specification
         uses: ./.github/actions/render