diff --git a/contrib/rootfs-builder/Makefile b/contrib/rootfs-builder/Makefile
index ca8042a91..9af382ba1 100644
--- a/contrib/rootfs-builder/Makefile
+++ b/contrib/rootfs-builder/Makefile
@@ -6,27 +6,27 @@ rootfs-%.tar.gz: rootfs/%/bin/echo
 	tar -czf $@ -C rootfs/$* .
 
 .PRECIOUS: rootfs/%/bin/busybox
-rootfs/%/bin/busybox: downloads/stage3-%-current.tar.bz2 rootfs-files
+rootfs/%/bin/busybox: downloads/stage3-%-current.tar rootfs-files
 	gpg --verify $<.DIGESTS.asc
 	(cd downloads && \
-		grep -A1 '^# SHA512 HASH' stage3-$*-current.tar.bz2.DIGESTS.asc | \
+		grep -A1 '^# SHA512 HASH' stage3-$*-current.tar.DIGESTS.asc | \
 		grep -v '^--' | \
 		sha512sum -c)
 	sudo rm -rf rootfs/$*
 	sudo mkdir -p rootfs/$*
-	sudo tar -xvf downloads/stage3-$*-current.tar.bz2 -C rootfs/$* \
+	sudo tar -xvf downloads/stage3-$*-current.tar -C rootfs/$* \
 		--no-recursion --wildcards $$(< rootfs-files)
 	sudo touch $@
 
 .PRECIOUS: rootfs/%/bin/echo
 rootfs/%/bin/echo: rootfs/%/bin/busybox
-	sudo sh -c 'COMMANDS=$$($< --list) || exit 1; for COMMAND in $${COMMANDS}; do \
+	sudo sh -c 'COMMANDS=$$($< --list | grep -v "^busybox$$") || exit 1; for COMMAND in $${COMMANDS}; do \
 		test -L "rootfs/$*/bin/$${COMMAND}" || ln -rs $< "rootfs/$*/bin/$${COMMAND}" || exit; \
 	done'
 
-downloads/stage3-%-current.tar.bz2: get-stage3.sh
+downloads/stage3-%-current.tar: get-stage3.sh
 	STAGE3_ARCH=$* ./$<
-	touch downloads/stage3-$*-*.tar.bz2
+	touch downloads/stage3-$*-*.tar
 
 clean:
 	rm -f downloads/*
diff --git a/contrib/rootfs-builder/get-stage3.sh b/contrib/rootfs-builder/get-stage3.sh
index 6828f0171..e6f558d6e 100755
--- a/contrib/rootfs-builder/get-stage3.sh
+++ b/contrib/rootfs-builder/get-stage3.sh
@@ -2,7 +2,7 @@
 #
 # Download the current Gentoo stage3
 #
-# Copyright (C) 2014-2015 W. Trevor King <wking@tremily.us>
+# Copyright (C) 2014-2018 W. Trevor King <wking@tremily.us>
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -16,8 +16,36 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+die()
+{
+	echo "$1"
+	exit 1
+}
+
 MIRROR="${MIRROR:-http://distfiles.gentoo.org/}"
-STAGE3_ARCH="${STAGE3_ARCH:-amd64}"
+if test -n "${STAGE3}"
+then
+	if test -n "${STAGE3_ARCH}"
+	then
+		die 'if you set STAGE3, you do not need to set STAGE3_ARCH'
+	fi
+	if test -n "${DATE}"
+	then
+		die 'if you set STAGE3, you do not need to set DATE'
+	fi
+	STAGE3_ARCH=$(echo "${STAGE3}" | sed -n 's/stage3-\([^-]*\)-.*/\1/p')
+	if test -z "${STAGE3_ARCH}"
+	then
+		die "could not calculate STAGE3_ARCH from ${STAGE3}"
+	fi
+	DATE=$(echo "${STAGE3}" | sed -n "s/stage3-${STAGE3_ARCH}-\([0-9TZ]*\)[.]tar[.].*/\1/p")
+	if test -z "${DATE}"
+	then
+		die "could not calculate DATE from ${STAGE3}"
+	fi
+else
+	STAGE3_ARCH="${STAGE3_ARCH:-amd64}"
+fi
 
 if test -z "${BASE_ARCH}"
 then
@@ -38,19 +66,35 @@ then
 fi
 
 BASE_ARCH_URL="${BASE_ARCH_URL:-${MIRROR}releases/${BASE_ARCH}/autobuilds/}"
-LATEST=$(wget -O - "${BASE_ARCH_URL}latest-stage3.txt")
-DATE=$(echo "${LATEST}" | sed -n "s|/stage3-${STAGE3_ARCH}-[0-9]*[.]tar[.]bz2.*||p")
+
+if test -z "${STAGE3}"
+then
+	LATEST=$(wget -O - "${BASE_ARCH_URL}latest-stage3.txt")
+	if test -z "${DATE}"
+	then
+		DATE=$(echo "${LATEST}" | sed -n "s|/stage3-${STAGE3_ARCH}-[0-9TZ]*[.]tar.*||p")
+		if test -z "${DATE}"
+		then
+			die "could not calculate DATE from ${BASE_ARCH_URL}latest-stage3.txt"
+		fi
+	fi
+
+	STAGE3=$(echo "${LATEST}" | sed -n "s|${DATE}/\(stage3-${STAGE3_ARCH}-${DATE}[.]tar[.][^ ]*\) .*|\1|p")
+	if test -z "${STAGE3}"
+	then
+		die "could not calculate STAGE3 from ${BASE_ARCH_URL}latest-stage3.txt"
+	fi
+fi
+
 ARCH_URL="${ARCH_URL:-${BASE_ARCH_URL}${DATE}/}"
-STAGE3="${STAGE3:-stage3-${STAGE3_ARCH}-${DATE}.tar.bz2}"
 STAGE3_CONTENTS="${STAGE3_CONTENTS:-${STAGE3}.CONTENTS}"
 STAGE3_DIGESTS="${STAGE3_DIGESTS:-${STAGE3}.DIGESTS.asc}"
 
-die()
-{
-	echo "$1"
-	exit 1
-}
-
+COMPRESSION=$(echo "${STAGE3}" | sed -n 's/^.*[.]\([^.]*\)$/\1/p')
+if test -z "${COMPRESSION}"
+then
+	die "could not calculate COMPRESSION from ${STAGE3}"
+fi
 for FILE in "${STAGE3}" "${STAGE3_CONTENTS}" "${STAGE3_DIGESTS}"; do
 	if [ ! -f "downloads/${FILE}" ]; then
 		wget -O "downloads/${FILE}" "${ARCH_URL}${FILE}"
@@ -60,7 +104,11 @@ for FILE in "${STAGE3}" "${STAGE3_CONTENTS}" "${STAGE3_DIGESTS}"; do
 		fi
 	fi
 
-	CURRENT=$(echo "${FILE}" | sed "s/${DATE}/current/")
+	FILE_NOCOMPRESSION=$(echo "${FILE}" | sed "s/[.]${COMPRESSION}//")
+	if [ "${FILE_NOCOMPRESSION}" = "${FILE}" ]; then
+		die "unable to remove .${COMPRESSION} from ${FILE}"
+	fi
+	CURRENT=$(echo "${FILE_NOCOMPRESSION}" | sed "s/${DATE}/current/")
 	(
 		cd downloads &&
 		rm -f "${CURRENT}" &&
@@ -68,4 +116,3 @@ for FILE in "${STAGE3}" "${STAGE3_CONTENTS}" "${STAGE3_DIGESTS}"; do
 		die "failed to link ${CURRENT} -> ${FILE}"
 	)
 done
-
diff --git a/contrib/rootfs-builder/rootfs-files b/contrib/rootfs-builder/rootfs-files
index 319a0f5f1..ac932eaf1 100644
--- a/contrib/rootfs-builder/rootfs-files
+++ b/contrib/rootfs-builder/rootfs-files
@@ -1,3 +1,6 @@
 ./bin/busybox
+./dev
 ./etc/group
 ./etc/passwd
+./proc
+./sys
diff --git a/rootfs-386.tar.gz b/rootfs-386.tar.gz
index 9e52effef..0e26e604c 100644
Binary files a/rootfs-386.tar.gz and b/rootfs-386.tar.gz differ
diff --git a/rootfs-amd64.tar.gz b/rootfs-amd64.tar.gz
index b440ce56e..d0f5fa515 100644
Binary files a/rootfs-amd64.tar.gz and b/rootfs-amd64.tar.gz differ