diff --git a/script/build b/script/build
index 0298b62..fca4a5e 100755
--- a/script/build
+++ b/script/build
@@ -29,7 +29,7 @@ else
   goreleaser build --snapshot --clean "$@"
 fi
 
-if [[ "$CI" == "true" ]]; then
+if [[ "${CI:-false}" == "true" ]]; then
   tree -L 2 -a --dirsfirst -C -F -h -D dist/
   echo "artifact_dir=dist" >> $GITHUB_OUTPUT
 fi