diff --git a/Makefile.docker b/Makefile.docker
index 932e35cc..d9512e5a 100644
--- a/Makefile.docker
+++ b/Makefile.docker
@@ -5,7 +5,7 @@ DEV_BUILD  := 0
 
 bin/rancheros:
 	mkdir -p $(dir $@)
-	go build -tags netgo -installsuffix netgo -ldflags "-X github.com/rancher/os/config.VERSION $(VERSION) -linkmode external -extldflags -static" -o $@
+	go build -tags netgo -installsuffix netgo -ldflags "-X github.com/rancher/os/config.VERSION=$(VERSION) -linkmode external -extldflags -static" -o $@
 	strip --strip-all $@