diff --git a/template/.ci/build_document.sh b/template/.ci/build_document.sh
index aa814ed..d2da9e0 100755
--- a/template/.ci/build_document.sh
+++ b/template/.ci/build_document.sh
@@ -5,4 +5,9 @@ mkdir public
 mv build/$mainfile.pdf public
 mv build/$mainfile.log public
 cd public/
-tree -H '.' -I "index.html" -D --charset utf-8 -T "$course" > index.html
+if ! command -v tree &> /dev/null
+then
+  echo "No tree utility found, skipping making tree"
+else
+  tree -H '.' -I "index.html" -D --charset utf-8 -T "$course" > index.html
+fi