diff --git a/Makefile b/Makefile
index 9ba2ac35b..b0ac3d0e3 100644
--- a/Makefile
+++ b/Makefile
@@ -1,19 +1,18 @@
-SHIPPER_IMAGE = bookingcom/shipper:latest
-METRICS_IMAGE = bookingcom/shipper-state-metrics:latest
-SHIPPER_NAMESPACE = shipper-system
-KUBECTL = kubectl -n $(SHIPPER_NAMESPACE)
+SHIPPER_IMAGE ?= bookingcom/shipper:latest
+METRICS_IMAGE ?= bookingcom/shipper-state-metrics:latest
+SHIPPER_NAMESPACE ?= shipper-system
+KUBECTL ?= kubectl -n $(SHIPPER_NAMESPACE)
+PKG = pkg/**/* vendor/**/*
 
-.PHONY: shipper
-
-shipper:
+shipper: $(PKG) cmd/shipper/* Dockerfile.shipper
 	GOARCH=amd64 CGO_ENABLED=0 GOOS=linux go build -o shipper ./cmd/shipper/*.go
-	docker build -f Dockerfile.shipper -t $SHIPPER_IMAGE --build-arg HTTP_PROXY=$(HTTP_PROXY) --build-arg HTTPS_PROXY=$(HTTPS_PROXY) .
-	docker push $SHIPPER_IMAGE
+	docker build -f Dockerfile.shipper -t $(SHIPPER_IMAGE) --build-arg HTTP_PROXY=$(HTTP_PROXY) --build-arg HTTPS_PROXY=$(HTTPS_PROXY) .
+	docker push $(SHIPPER_IMAGE)
 
-shipper-state-metrics:
+shipper-state-metrics: $(PKG) cmd/shipper-state-metrics/* Dockerfile.shipper-state-metrics
 	GOARCH=amd64 CGO_ENABLED=0 GOOS=linux go build -o shipper-state-metrics ./cmd/shipper-state-metrics/*.go
-	docker build -f Dockerfile.shipper-state-metrics -t $METRICS_IMAGE --build-arg HTTP_PROXY=$(HTTP_PROXY) --build-arg HTTPS_PROXY=$(HTTPS_PROXY) .
-	docker push $METRICS_IMAGE
+	docker build -f Dockerfile.shipper-state-metrics -t $(METRICS_IMAGE) --build-arg HTTP_PROXY=$(HTTP_PROXY) --build-arg HTTPS_PROXY=$(HTTPS_PROXY) .
+	docker push $(METRICS_IMAGE)
 
 restart:
 	# Delete all Pods in namespace, to force the ReplicaSet to spawn new ones