@@ -95,6 +95,21 @@ if [ -d "$rootfsDir/etc/apt/apt.conf.d" ]; then

 	Acquire::Languages "none";

 	EOF

+

+	echo >&2 "+ echo Acquire::GzipIndexes 'true' > '$rootfsDir/etc/apt/apt.conf.d/docker-gzip-indexes'"

+	cat > "$rootfsDir/etc/apt/apt.conf.d/docker-gzip-indexes" <<-'EOF'

+	# Since Docker users using "RUN apt-get update && apt-get install -y ..." in

+	# their Dockerfiles don't go delete the lists files afterwards, we want them to

+	# be as small as possible on-disk, so we explicitly request "gz" versions and

+	# tell Apt to keep them gzipped on-disk.

+

+	# For comparison, an "apt-get update" layer without this on a pristine

+	# "debian:wheezy" base image was "29.88 MB", where with this it was only

+	# "8.273 MB".

+

+	Acquire::GzipIndexes "true";

+	Acquire::CompressionTypes::Order:: "gz";

+	EOF

 fi

 if [ -z "$DONT_TOUCH_SOURCES_LIST" ]; then