diff --git a/cmd/lifecycled/main.go b/cmd/lifecycled/main.go
index 39f451e..f9b8c6e 100644
--- a/cmd/lifecycled/main.go
+++ b/cmd/lifecycled/main.go
@@ -50,6 +50,7 @@ func main() {
 		BoolVar(&disableSpotListener)
 
 	app.Flag("handler", "The script to invoke to handle events").
+		Required().
 		FileVar(&handler)
 
 	app.Flag("json", "Enable JSON logging").