diff --git a/Makefile b/Makefile
index 1cd872b..3c55c85 100644
--- a/Makefile
+++ b/Makefile
@@ -3,12 +3,17 @@ all: build
 	./basicwindow
 
 build:
+ifeq ($(GO111MODULE),)
+	echo no. you must use GO111MODULE here
+	false
+else
 	-rm -f basicwindow
 	go build -v -x
+endif
 
 stderr: build
-	echo "writing to /tmp/helloworld.stderr"
-	./helloworld >/tmp/helloworld.stderr 2>&1
+	echo "writing to /tmp/basicwindow.stderr"
+	./basicwindow >/tmp/basicwindow.stderr 2>&1
 
 push:
 	git add --all