btrbk: base config for snapshots.

services/btrbk.nix

@@ -0,0 +1,26 @@
+{
+  config,
+  lib,
+  ...
+}:
+
+with lib;
+
+mkIf (elem "btrbk" config.machine.services) {
+  services.btrbk.instances = {
+    "persist" = {
+      onCalendar = "hourly";
+      settings = {
+        timestamp_format = "long";
+        snapshot_preserve_min = "1w";
+        volume = {
+          "/" = {
+            snapshot_preserve = "20d 10w *m";
+            snapshot_dir = "/snapshots";
+            subvolume = "/persist";
+          };
+        };
+      };
+    };
+  };
+}