diff --git a/main.go b/main.go
index 29d233c..8c416b8 100644
--- a/main.go
+++ b/main.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"flag"
 	"image"
 	"image/color"
 	_ "image/png"
@@ -13,12 +14,16 @@ import (
 	"github.com/hajimehoshi/ebiten/v2"
 )
 
+var rewriteLevel1 = flag.Bool("rewrite_level_1", false, "Rewrites level1.gobz from an inbuilt struct literal")
+
 func main() {
+	flag.Parse()
+
 	ebiten.SetWindowResizable(true)
 	ebiten.SetWindowSize(640, 480)
 	ebiten.SetWindowTitle("TODO")
 
-	if false {
+	if *rewriteLevel1 {
 		writeLevel1()
 	}