diff --git a/pkg/format/Dockerfile b/pkg/format/Dockerfile
index 40365f32b..6c1dd4edf 100644
--- a/pkg/format/Dockerfile
+++ b/pkg/format/Dockerfile
@@ -1,18 +1,21 @@
-FROM linuxkit/alpine:c5021a113803f7608e3908014d316c3490183d0b@sha256:4c7a80173c71ca5019dc56f40442b3a8345f141dd46593bd1fe6d130294d07cb AS mirror
+FROM linuxkit/alpine:6336329f15b4166514782eaa555cf0ffd35c519c@sha256:f6c2ce92910b1d6e4e5557850a554f4a3ae9f66c1e89ad86a24d6c6e550f165e AS mirror
 
-FROM alpine:3.5@sha256:dfbd4a3a8ebca874ebd2474f044a0b33600d4523d03b0df76e5c5986cb02d7e8
-COPY --from=mirror /etc/apk/repositories /etc/apk/repositories
-COPY --from=mirror /etc/apk/keys /etc/apk/keys/
-COPY --from=mirror /mirror /mirror/
-
-RUN apk add \
+RUN mkdir -p /out/etc/apk && cp -r /etc/apk/* /out/etc/apk/
+RUN apk add --no-cache --initdb -p /out \
+    alpine-baselayout \
+    busybox \
     e2fsprogs \
     e2fsprogs-extra \
     jq \
+    musl \
     sfdisk \
     && true
+RUN rm -rf /out/etc/apk /out/lib/apk /out/var/cache
 
-RUN rm -rf /mirror /etc/apk/repositories /etc/apk/keys
-
-COPY . ./
+FROM scratch
+ENTRYPOINT []
+CMD []
+WORKDIR /
+COPY --from=mirror /out/ /
+COPY format.sh /
 CMD ["/bin/sh", "/format.sh"]
diff --git a/pkg/format/Makefile b/pkg/format/Makefile
index 8234712cc..f43012840 100644
--- a/pkg/format/Makefile
+++ b/pkg/format/Makefile
@@ -1,14 +1,15 @@
 .PHONY: tag push
 default: push
 
+ORG?=linuxkit
 IMAGE=format
 DEPS=Dockerfile format.sh
 
 HASH?=$(shell git ls-tree HEAD -- ../$(notdir $(CURDIR)) | awk '{print $$3}')
 
 tag: $(DEPS)
-	docker build --squash --no-cache --network=none -t linuxkit/$(IMAGE):$(HASH) .
+	docker build --squash --no-cache --network=none -t $(ORG)/$(IMAGE):$(HASH) .
 
 push: tag
-	docker pull linuxkit/$(IMAGE):$(HASH) || \
-	docker push linuxkit/$(IMAGE):$(HASH)
+	docker pull $(ORG)/$(IMAGE):$(HASH) || \
+	docker push $(ORG)/$(IMAGE):$(HASH)