diff --git a/scripts/0_prepare.sh b/scripts/0_prepare.sh
index 52cc6e55..7fc397b1 100644
--- a/scripts/0_prepare.sh
+++ b/scripts/0_prepare.sh
@@ -59,7 +59,7 @@ function prepare_image_files() {
 
   images=$(get_images)
   for image in ${images}; do
-    filename=$(basename "${image}").tar
+    filename=$(basename "${image}").zst
     image_path="${IMAGE_DIR}/${filename}"
     md5_filename=$(basename "${image}").md5
     md5_path="${IMAGE_DIR}/${md5_filename}"
@@ -83,7 +83,8 @@ function prepare_image_files() {
       fi
     fi
     echo "$(gettext 'Save image') ${image} -> ${image_path}"
-    docker save -o "${image_path}" "${image}" &
+    # docker save -o "${image_path}" "${image}" &
+    docker save "${image}" | zstd -f -q -o "${image_path}" &
     echo "${image_id}" >"${md5_path}" &
   done
   wait
diff --git a/scripts/3_load_images.sh b/scripts/3_load_images.sh
index dde6f0a4..ae8bf7c5 100755
--- a/scripts/3_load_images.sh
+++ b/scripts/3_load_images.sh
@@ -10,7 +10,7 @@ IMAGE_DIR="images"
 function load_image_files() {
   images=$(get_images)
   for image in ${images}; do
-    filename=$(basename "${image}").tar
+    filename=$(basename "${image}").zst
     filename_windows=${filename/:/_}
     if [[ -f ${IMAGE_DIR}/${filename_windows} ]]; then
       filename=${filename_windows}
@@ -39,7 +39,7 @@ function load_image_files() {
 }
 
 function main() {
-  if [[ -d "${IMAGE_DIR}" && $(find "${IMAGE_DIR}" -type f -name "*.tar" -print -quit 2>/dev/null) ]]; then
+  if [[ -d "${IMAGE_DIR}" && $(find "${IMAGE_DIR}" -type f -name "*.zst" -print -quit 2>/dev/null) ]]; then
     load_image_files
   else
     pull_images