diff --git a/luau/examples/rainbowify.luau b/luau/examples/rainbowify.luau
index 8c12603..e4fea66 100644
--- a/luau/examples/rainbowify.luau
+++ b/luau/examples/rainbowify.luau
@@ -1,39 +1,39 @@
 --!strict
 
+type term_color_func = (string) -> string
+
+local function rainbowify(str: string, color_map: {term_color_func}): string
+	local chars = str:split('')
+	for i, char in chars do
+		chars[i] = char ~= ' ' and color_map[i%5+1](char) or char
+	end
+	return table.concat(chars)
+end
+
 local function rainbowify_foreground(message: string): string
-	local parsed_terminal_message: {string} = {}
-	local color_map = {
+	return rainbowify(message, {
 		TERMINAL.OUT.FOREGROUND.RED,
 		TERMINAL.OUT.FOREGROUND.YELLOW,
 		TERMINAL.OUT.FOREGROUND.GREEN,
 		TERMINAL.OUT.FOREGROUND.BLUE,
 		TERMINAL.OUT.FOREGROUND.MAGENTA,
-	}
-
-	for i, char in message:split('') do
-		table.insert(parsed_terminal_message, char ~= ' ' and color_map[i%5+1](char) or char)
-	end
-	return table.concat(parsed_terminal_message)
+	})
 end
 
 local function rainbowify_background(message: string): string
-	local parsed_terminal_message: {string} = {}
-	local color_map = {
+	return rainbowify(message, {
 		TERMINAL.OUT.BACKGROUND.RED,
 		TERMINAL.OUT.BACKGROUND.YELLOW,
 		TERMINAL.OUT.BACKGROUND.GREEN,
 		TERMINAL.OUT.BACKGROUND.BLUE,
 		TERMINAL.OUT.BACKGROUND.MAGENTA,
-	}
-
-	for i, char in message:split('') do
-		table.insert(parsed_terminal_message, char ~= ' ' and color_map[i%5+1](char) or char)
-	end
-	return table.concat(parsed_terminal_message)
+	})
 end
 
 print(rainbowify_foreground("Rainbow foreground"))
-print(rainbowify_background("Rainbow background"))
+print(
+	TERMINAL.OUT.FOREGROUND.BLACK(rainbowify_background("Rainbow background with black text"))
+)
 print(
 	TERMINAL.OUT.BACKGROUND.DARK_GREY(rainbowify_foreground("Rainbow foreground on a dark grey background"))
 )
\ No newline at end of file