diff --git a/role/backup.nix b/role/backup.nix
index e019b7e..759304f 100644
--- a/role/backup.nix
+++ b/role/backup.nix
@@ -1,10 +1,12 @@
+# Regular backup role to a separate device
 {
- systemdMount,
- borgArchiveFolder,
+ systemdMount, # Systemd mount name
+ borgArchiveFolder, # Absolute borg root folder
  keepWithin? "14d",
  keepWeekly? "4",
  keepMonthly? "6",
  keepYearly? "-1",
+ schedule? "13:37", # Systemd Schedule of backup timer
 }:
 
 let pkgs = import<nixpkgs>{};
@@ -56,7 +58,7 @@ in
       description = "Backup Schedule";
 
       timerConfig = {
-        OnCalendar = "13:37";
+        OnCalendar = schedule;
         Persistent = "true";
       };