diff --git a/lib/sandbox_helper.sh b/lib/sandbox_helper.sh
index df69d97..4ea5ec5 100644
--- a/lib/sandbox_helper.sh
+++ b/lib/sandbox_helper.sh
@@ -61,8 +61,8 @@ if [ "$NO_SANDBOX" = false ]; then
   env -i $(
     if [[ -n "$KEEP_ENV" ]]; then
       IFS=',' read -ra VARS <<< "$KEEP_ENV"
-      for var in "''${VARS[@]}"; do
-        printf '%s=%q ' "$var" "''${!var}"
+      for var in "${VARS[@]}"; do
+        printf '%s=%q ' "$var" "${!var}"
       done
     fi
   ) bash $actualJobScript