diff --git a/lib/spectrum.zsh b/lib/spectrum.zsh
index 13aaf8adb..86a939e8a 100644
--- a/lib/spectrum.zsh
+++ b/lib/spectrum.zsh
@@ -16,6 +16,7 @@ FX=(
 
 # Build the tables with array operations instead of a 256-iteration loop
 () {
+  setopt localoptions noksharrays
   local -a codes fg bg
   codes=({000..255})
   fg=( "%{"$'\e'"[38;5;"${^codes}"m%}" )