diff --git a/docker.sh b/docker.sh
index 3f5eef3..84c4f21 100755
--- a/docker.sh
+++ b/docker.sh
@@ -56,10 +56,23 @@ if [[ ! -z ${DRY_RUN:-} ]]; then
 	export APT_DRY_RUN=1
 fi
 base_url="https://apt.dockerproject.org/repo"
+remote_filelist="${APT_PATH}/filelist.remote"
+local_filelist="${APT_PATH}/filelist.local"
+
 for version in ${APT_VERSIONS[@]}; do
-	apt-download-binary ${base_url} "$version" "main" "amd64" "${APT_PATH}" || true
-	apt-download-binary ${base_url} "$version" "main" "i386" "${APT_PATH}" || true
+	apt-download-binary ${base_url} "$version" "main" "amd64" "${APT_PATH}" ${remote_filelist} || true
+	apt-download-binary ${base_url} "$version" "main" "i386" "${APT_PATH}"  ${remote_filelist} || true
 done
 
+APT_BACKUP_PATH="${BASE_PATH}/backup/apt"
+mkdir -p ${APT_BACKUP_PATH}
+(cd ${APT_PATH}; find . -type f -iname "*.deb") | sed 's+^\./++' > ${local_filelist}
+comm <(sort $remote_filelist) <(sort $local_filelist) -13 | while read file; do
+	echo "deleting ${file}"
+	mv $file ${APT_BACKUP_PATH}
+done
+
+rm ${remote_filelist} ${local_filelist}
+
 # sync_docker "http://apt.dockerproject.org/" "${TUNASYNC_WORKING_DIR}/apt"
 # sync_docker "http://yum.dockerproject.org/" "${TUNASYNC_WORKING_DIR}/yum"
diff --git a/helpers/apt-download b/helpers/apt-download
index d12927f..5cd02f5 100644
--- a/helpers/apt-download
+++ b/helpers/apt-download
@@ -17,6 +17,8 @@ function apt-download-binary() {
 	local repo=$3
 	local arch=$4
 	local dest_base_dir=$5
+	local filelist="${6:-"/dev/null"}"
+
 	if [ -z $dest_base_dir ]; then
 		echo "Destination directory is empty, cannot continue"
 		return 1
@@ -130,6 +132,7 @@ function apt-download-binary() {
 	# Download packages
 	(echo -e "${pkgidx_content}" | grep -e '^Filename' -e '^Size' -e ${checksum_regex} | cut -d' ' -f 2) | \
 	while read pkg_filename; read pkg_size; read pkg_checksum; do
+		echo ${pkg_filename} >> $filelist
 		dest_filename="${dest_base_dir}/${pkg_filename}"
 		dest_dir=`dirname ${dest_filename}`
 		[ ! -d "$dest_dir" ] && mkdir -p "$dest_dir"
diff --git a/test/apt_test.sh b/test/apt_test.sh
new file mode 100755
index 0000000..7d842f4
--- /dev/null
+++ b/test/apt_test.sh
@@ -0,0 +1,39 @@
+#!/bin/bash
+# reqires: wget, yum-utils
+
+set -e
+set -o pipefail
+
+_here=`dirname $(realpath $0)`
+_here=`dirname ${_here}`
+
+. ${_here}/helpers/apt-download
+APT_VERSIONS=("debian-jessie" "debian-stretch" "ubuntu-xenial")
+
+BASE_PATH="${TUNASYNC_WORKING_DIR}"
+APT_PATH="${BASE_PATH}/apt/repo"
+
+mkdir -p ${APT_PATH}
+
+# APT mirror 
+if [[ ! -z ${DRY_RUN:-} ]]; then
+	export APT_DRY_RUN=1
+fi
+base_url="https://apt.dockerproject.org/repo"
+remote_filelist="${APT_PATH}/filelist.remote"
+local_filelist="${APT_PATH}/filelist.local"
+
+for version in ${APT_VERSIONS[@]}; do
+	apt-download-binary ${base_url} "$version" "main" "amd64" "${APT_PATH}" ${remote_filelist} || true
+	apt-download-binary ${base_url} "$version" "main" "i386" "${APT_PATH}" ${remote_filelist} || true
+done
+
+APT_BACKUP_PATH="${BASE_PATH}/backup/apt"
+mkdir -p ${APT_BACKUP_PATH}
+(cd ${APT_PATH}; find . -type f -iname "*.deb") | sed 's+^\./++' > ${local_filelist}
+comm <(sort $remote_filelist) <(sort $local_filelist) -13 | while read file; do
+	echo "deleting ${file}"
+	mv $file ${APT_BACKUP_PATH}
+done
+
+rm ${remote_filelist} ${local_filelist}