diff --git a/README.md b/README.md
index b9fd204a..6c44ac21 100644
--- a/README.md
+++ b/README.md
@@ -24,6 +24,7 @@ Supported authorization methods:
 A public Docker image is available on Docker Hub: [cesanta/docker_auth:stable](https://registry.hub.docker.com/u/cesanta/docker_auth/).
 
 The binary takes a single argument - path to the config file.
+If no arguments are given, the Dockerfile defaults to `/config/auth_config.yml`.
 
 Example command line:
 
diff --git a/auth_server/.gitignore b/auth_server/.gitignore
index 24443656..e7285974 100644
--- a/auth_server/.gitignore
+++ b/auth_server/.gitignore
@@ -1 +1,2 @@
 auth_server
+Godeps/
diff --git a/auth_server/Dockerfile b/auth_server/Dockerfile
index 2e89ef53..1dfd7c0c 100644
--- a/auth_server/Dockerfile
+++ b/auth_server/Dockerfile
@@ -1,4 +1,5 @@
-FROM golang:1.5
+FROM busybox
 EXPOSE 5001
-ADD auth_server /
 ENTRYPOINT ["/auth_server"]
+CMD ["/config/auth_config.yml"]
+COPY auth_server .
diff --git a/auth_server/Makefile b/auth_server/Makefile
index c8e856d7..97ea0aa1 100644
--- a/auth_server/Makefile
+++ b/auth_server/Makefile
@@ -1,20 +1,34 @@
-.PHONY: update-deps build docker-build
+MAKEFLAGS += --warn-undefined-variables
+IMAGE ?= cesanta/docker_auth
+COMPRESS_BINARY ?= false
+
+BUILDER_IMAGE ?= centurylink/golang-builder
+BUILDER_IMAGE_EXTRA-build-cross = -cross
+BUILDER_OPTS-docker-build = -v /var/run/docker.sock:/var/run/docker.sock
+
+.PHONY: %
 
 all: build
+local: build-local
 
 update-deps:
-	go get -v -u -f github.com/jteeuwen/go-bindata/... .
+	go get -v -u -f github.com/tools/godep github.com/jteeuwen/go-bindata/... .
 
-build:
+godep:
+	godep save
+
+build-local: update-deps
 	go generate ./...
 	go build
 
-docker-build: update-deps build
-	docker build -t cesanta/docker_auth -f Dockerfile .
+build build-cross docker-build: update-deps godep
+	docker run --rm -v $(PWD):/src -e COMPRESS_BINARY=$(COMPRESS_BINARY) $(BUILDER_OPTS-$@) $(BUILDER_IMAGE)$(BUILDER_IMAGE_EXTRA-$@) $(IMAGE)
+
+docker-tag-%:
+	docker tag -f $(IMAGE):latest $(IMAGE):$*
 
-docker-push-latest:
-	docker push cesanta/docker_auth:latest
+docker-push-%: docker-tag-%
+	docker push $(IMAGE):$*
 
-docker-push-stable:
-	docker tag -f cesanta/docker_auth:latest cesanta/docker_auth:stable
-	docker push cesanta/docker_auth:stable
+# Shortcut for latest
+docker-push: docker-push-latest
diff --git a/auth_server/main.go b/auth_server/main.go
index 4916c79b..305fee61 100644
--- a/auth_server/main.go
+++ b/auth_server/main.go
@@ -14,7 +14,7 @@
    limitations under the License.
 */
 
-package main
+package main // import "github.com/cesanta/docker_auth/auth_server"
 
 import (
 	"crypto/tls"