diff --git a/spcd/bootstrap.sh b/spcd/bootstrap.sh
index 666b589..52e0ff3 100644
--- a/spcd/bootstrap.sh
+++ b/spcd/bootstrap.sh
@@ -40,19 +40,20 @@ _spcd_banner_add() {
 }
 
 _spcd_banner_add_index() {
-    unset spcd_bai__label
-    unset spcd_bai__level
+    local label
+    local level
+    local value
     while true; do
-        spcd_bai__level=$((spcd_bai__level + 1))
-        eval "spcd_bai__value=\"\${__SPCD_STEP_${spcd_bai__level}_INDEX}\""
-        [ -n "${spcd_bai__value}" ] || break
-        if [ -n "${spcd_bai__label}" ]; then
-            spcd_bai__label="${spcd_bai__label}.${spcd_bai__value}"
+        level=$((level + 1))
+        eval "value=\"\${__SPCD_STEP_${level}_INDEX}\""
+        [ -n "${value}" ] || break
+        if [ -n "${label}" ]; then
+            label="${label}.${value}"
         else
-            spcd_bai__label="${spcd_bai__value}"
+            label="${value}"
         fi
     done
-    _spcd_banner_add "${spcd_bai__label}"
+    _spcd_banner_add "${label}"
 }
 
 _spcd_banner_append() {