diff --git a/Makefile b/Makefile
index 4a672cec5..3989cfa0d 100644
--- a/Makefile
+++ b/Makefile
@@ -74,8 +74,7 @@ clean:
 	-rm Dockerfile
 
 supervisor-dind:
-	sed -i 's/\(ENV PASSWORDLESS_DROPBEAR\).*/\1 ${PASSWORDLESS_DROPBEAR}/' tools/dind/Dockerfile
-	cd tools/dind && docker build $(DOCKER_HTTP_PROXY) $(DOCKER_HTTPS_PROXY) --no-cache=$(DISABLE_CACHE) -t resin/resin-supervisor-dind:$(SUPERVISOR_VERSION) .
+	cd tools/dind && docker build $(DOCKER_HTTP_PROXY) $(DOCKER_HTTPS_PROXY) --no-cache=$(DISABLE_CACHE) --build-arg PASSWORDLESS_DROPBEAR=$(PASSWORDLESS_DROPBEAR) -t resin/resin-supervisor-dind:$(SUPERVISOR_VERSION) .
 
 run-supervisor: supervisor-dind stop-supervisor
 	cd tools/dind \
diff --git a/tools/dind/Dockerfile b/tools/dind/Dockerfile
index cbc3add53..aee192f29 100644
--- a/tools/dind/Dockerfile
+++ b/tools/dind/Dockerfile
@@ -14,7 +14,7 @@ ENV DOCKER_VERSION 1.10.3
 ENV RELEASE_NAME jessie
 
 # Change to 'true' to allow blank password dropbear logins on dind HostOS
-ENV PASSWORDLESS_DROPBEAR false
+ARG PASSWORDLESS_DROPBEAR=false
 
 COPY config/certs/ /usr/local/share/ca-certificates/
 RUN rm -f /usr/local/share/ca-certificates/.keepme ; update-ca-certificates