diff --git a/Makefile b/Makefile
index 500b18a..bf7e312 100644
--- a/Makefile
+++ b/Makefile
@@ -9,7 +9,7 @@ all: build test
 tag:
 	echo $(TAG)
 dep:
-	go mod download && go mod vendor && go install -i ./vendor/...
+	env GO111MODULE=on go mod download && env GO111MODULE=on go mod vendor && go install -i ./vendor/...
 clean:
 	rm -fv bin/contentserve*