diff --git a/make-tarball.sh b/make-tarball.sh
new file mode 100755
index 0000000..b0c0b8b
--- /dev/null
+++ b/make-tarball.sh
@@ -0,0 +1,23 @@
+#!/bin/sh
+
+# args
+repo="${1%/}"
+ref="${2-HEAD}"
+
+# check
+if test ! -d "${repo}/.git"; then
+    echo "usage: $0 <repodir> [ <ref> ]"
+    exit 1
+fi
+
+# get + print info
+commit=$(cd $repo; git show --pretty='format:%h' $ref | head -1)
+date=$(cd $repo; git show --pretty='format:%cs' $ref | head -1 | tr -d '-')
+echo "# $repo $ref  ->  commit $commit - date $date"
+
+# create tarball
+name="${repo##*/}"
+file="${name}-${commit}.tar.xz"
+(cd $repo; git archive --format=tar --prefix=${name}-${commit}/ ${commit}) \
+    | xz -9ev > "$file"
+echo "# $file written"