diff --git a/.github/workflows/sync-upstream.yml b/.github/workflows/sync-upstream.yml
index bd60234..56a9b94 100644
--- a/.github/workflows/sync-upstream.yml
+++ b/.github/workflows/sync-upstream.yml
@@ -68,6 +68,12 @@ jobs:
             ./$project/metadata.json | tee ./$project/metadata.json.tmp
           # Replace the original file
           mv ./$project/{metadata.json.tmp,metadata.json}
+          # Update vendorHash
+          vendor=$(nix --log-format raw build .#$project 2>&1 | grep  "got: " | awk '/got: / {print $NF}' || echo "")
+          jq --arg vendor "$vendor" \
+             '.vendorHash = $vendor' \
+             ./$project/metadata.json | tee ./$project/metadata.json.tmp
+          mv ./$project/{metadata.json.tmp,metadata.json}
 
       - name: Commit changes and push
         uses: EndBug/add-and-commit@main