diff --git a/mastus/backup.nix b/mastus/backup.nix
new file mode 100644
index 0000000..d0325cd
--- /dev/null
+++ b/mastus/backup.nix
@@ -0,0 +1,11 @@
+{ config, pkgs, ... }:
+
+{
+
+  environment.systemPackages = [ pkgs.rdiff-backup ];
+
+  users.extraUsers.root.openssh.authorizedKeys.keys = [
+    ''command="rdiff-backup --server --restrict-read-only /",no-port-forwarding,no-X11-forwarding,no-pty ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCiZhy9mm9sUeomfe9Vj5JhNE4l7YOkj7Yiii5Ni2RzUyj/dc9pxvNJSI+om/ruwb1n2gIYi0bOpwrZGiyvrUrpiqLcOwU6IOYLxnQ3E9nHLX3rsGMIyJtMcoBOcTY/rJMogqA4m6uMaaPEaeBlS5F/qb5UGIvQ7YlW1rF75RJ/QXrdL3Y7R3OJbG90QGR5EThs/1HOEBUKgkEcPQDodzNvZ8hFtznWrCw5bMSQYGMfY4WBc1b7UdLaYZ6vghQgsZ5IyvFDvCNTHTfhObYhv71YMXDkocAyI8XecNP1hoJ67oZ1xn06LEUEMiuXIQ4Ss7RYZLzNc2yrd5RYqCdd4x1n backups@aruanus''
+  ];
+
+}
diff --git a/mastus/configuration.nix b/mastus/configuration.nix
index 01334ce..8e94847 100644
--- a/mastus/configuration.nix
+++ b/mastus/configuration.nix
@@ -5,6 +5,7 @@
     [
       /etc/nixos/hardware-configuration.nix
       ../basic-tools.nix
+      ./backup.nix
 
       ./mail.nix
       ./gogs.nix