WIP: xps16/btrfs: enable btrbk

hosts/xps16/services/btrfs.nix

@@ -1,4 +1,37 @@
 { ... }:
 {
   services.btrfs.autoScrub.enable = true;
+
+  services.btrbk = {
+    # instances = let
+    #   withDefaults = path: conf: lib.recursiveUpdate {
+    #     onCalendar = "daily";
+    #     settings = {
+    #       timestamp_format = "long";
+    #       snapshot_preserve_min = "2d";
+    #       snapshot_preserve = "14d";
+    #       volume.${path} = {
+    #         snapshot_create = "always";
+    #         subvolume = ".";
+    #         snapshot_dir = ".snapshots";
+    #       };
+    #     };
+    #   } conf;
+# ."var-log"
+    # in {
+    #   "var-log" = 
+    #   settings = {
+    #     volume."/home" = {
+    #       snapshot_create = "always";
+    #       subvolume = ".";
+    #       snapshot_dir = ".snapshots";
+    #     };
+    #     # volume."/var/local" = {
+    #     #   snapshot_create = "always";
+    #     #   subvolume = ".";
+    #     #   snapshot_dir = ".snapshots";
+    #     # };
+    #   };
+    # };
+  };
 }