diff --git a/nixos/modules/default.nix b/nixos/modules/default.nix
index 09796ef543026ce947dd18c600f98617b9eb3f5d..86ce85c11d71b42c81ad8d4c06f1eb5275649e05 100644
--- a/nixos/modules/default.nix
+++ b/nixos/modules/default.nix
@@ -13,6 +13,7 @@
     ./packages.nix
     ./issuer.nix
     ./private-storage.nix
+    ./monitoring/policy.nix
     ./monitoring/vpn/client.nix
     ./monitoring/exporters/node.nix
     ./monitoring/exporters/tahoe.nix
diff --git a/nixos/modules/monitoring/policy.nix b/nixos/modules/monitoring/policy.nix
new file mode 100644
index 0000000000000000000000000000000000000000..599d0bb4d58d90517b6b53fdf653aec53e34558e
--- /dev/null
+++ b/nixos/modules/monitoring/policy.nix
@@ -0,0 +1,11 @@
+# Codify our log data retention policy
+
+{ options, lib, ... }: {
+  options.services.private-storage.monitoring.policy = {
+    logRetentionSeconds = lib.mkOption {
+      type = lib.types.int;
+      description = "How long do we retain logs (seconds)";
+      default = 29 * (24 * 60 * 60);  # 29 days.
+    };
+  };
+}