diff --git a/bin/update b/bin/update
index 81c6999..e01e913 100755
--- a/bin/update
+++ b/bin/update
@@ -8,7 +8,7 @@ REV_FILE="$ROOT/works/rev"
 
 # defaults
 REPO_URL="git@git.inker.bot:arknights/sing-box.git"
-if [[ $CI_JOB_TOKEN != "" ]]; then
+if [ ! -z $CI_JOB_TOKEN ]; then
   REPO_URL=$(echo $REPO_URL | sed -i "s/git/gitlab-ci-token:$CI_JOB_TOKEN/")
 fi
 UPSTREAM_BRANCH="main"