diff --git a/home_external/.bashrc b/home_external/.bashrc
index 1b5d147..2ff28c1 100644
--- a/home_external/.bashrc
+++ b/home_external/.bashrc
@@ -186,26 +186,29 @@ colours() {
 
 # ex - archive extractor
 # usage: ex <file>
-ex ()
-{
-  if [ -f $1 ] ; then
-    case $1 in
-      *.tar.bz2)   tar xjf $1   ;;
-      *.tar.gz)    tar xzf $1   ;;
-      *.bz2)       bunzip2 $1   ;;
-      *.rar)       unrar x $1   ;;
-      *.gz)        gunzip $1    ;;
-      *.tar)       tar xf $1    ;;
-      *.tbz2)      tar xjf $1   ;;
-      *.tgz)       tar xzf $1   ;;
-      *.zip)       unzip $1     ;;
-      *.Z)         uncompress $1;;
-      *.7z)        7z x $1      ;;
-      *)           echo "'$1' cannot be extracted via ex()" ;;
-    esac
-  else
-    echo "'$1' is not a valid file"
-  fi
+ex() {
+   if [[ ! -f "$1" ]]; then
+      echo "'$1' is not a valid file"
+      return 1;
+   fi
+   # FIXME 7z kann (theoretisch) tar
+   outdir=${1%.*}
+   case "$1" in
+      *.tar.bz2 | *.tbz | *.tbz2)
+         tar xjf $1 -C $outdir;;
+      *.tar.gz  | *.tgz)
+         tar xzf $1 -C $outdir;;
+      *.tar)
+         tar xf $1 -C $outdir;;
+      *.7z | *.zip | *.gz | *.bz | *.bz2)
+         7z x -o$outdir $1;;
+      *.rar)
+         unrar x $1;;
+      *.Z)
+         uncompress $1;;
+      *)
+         echo "'$1' cannot be extracted via ex()";;
+   esac
 }
 
 # BEGIN_KITTY_SHELL_INTEGRATION
diff --git a/scripts/backup_edi.sh b/scripts/backup_edi.sh
index 434ea39..d9d1291 100755
--- a/scripts/backup_edi.sh
+++ b/scripts/backup_edi.sh
@@ -10,20 +10,47 @@ shopt -s expand_aliases # make aliases work
 ###############################
 
 BACKUP_DIR=/sync/backup
+ensureDirectory $BACKUP_DIR
 BACKUP_DIR_HOME=$BACKUP_DIR/home
-rsync_backup $HOME/.ssh/ $BACKUP_DIR_HOME/.ssh/
+ensureDirectory $BACKUP_DIR_HOME
+backupDirectory $HOME/.ssh/ $BACKUP_DIR_HOME/.ssh/
 
 BACKUP_DIR_ROOT=$BACKUP_DIR/root/etc
-sd rsync_backup /etc/ddclient/ $BACKUP_DIR_ROOT/ddclient/
-sd rsync_backup /etc/ddclient.conf $BACKUP_DIR_ROOT/
-sd rsync_backup /etc/letsencrypt/ $BACKUP_DIR_ROOT/letsencrypt/
-sd rsync_backup /etc/nginx/ $BACKUP_DIR_ROOT/nginx/
-sd rsync_backup /etc/ssh/ $BACKUP_DIR_ROOT/ssh/
-sd rsync_backup /etc/wireguard/ $BACKUP_DIR_ROOT/wireguard/
+ensureRootDirectory $BACKUP_DIR_ROOT
 sd rsync_backup /etc/hosts $BACKUP_DIR_ROOT/
-sd rsync_backup /etc/docker/daemon.json $BACKUP_DIR_ROOT/docker/
+sd rsync_backup /etc/ddclient.conf $BACKUP_DIR_ROOT/
+backupRootDirectory /etc/ddclient/ $BACKUP_DIR_ROOT/ddclient/
+backupRootDirectory /etc/letsencrypt/ $BACKUP_DIR_ROOT/letsencrypt/
+backupRootDirectory /etc/nginx/ $BACKUP_DIR_ROOT/nginx/
+backupRootDirectory /etc/ssh/ $BACKUP_DIR_ROOT/ssh/
+backupRootDirectory /etc/wireguard/ $BACKUP_DIR_ROOT/wireguard/
+backupRootDirectory /etc/docker/daemon.json $BACKUP_DIR_ROOT/docker/
 
 
+backupRootDirectory() {
+   ensureRootDirectory $2
+   sd rsync_backup $1 $2
+}
+
+
+backupDirectory() {
+   ensureDirectory $2
+   rsync_backup $1 $2
+}
+
+
+ensureRootDirectory() {
+   ensureDirectory $1
+   sudo chown root:root $1
+}
+
+
+ensureDirectory() {
+   if [[ ! -e $1 ]]; then
+      mkdir -p $1
+   fi
+}
+
 #####################
 ### upload backup ###
 #####################