backup nixos containers on vpsfree

nixos/boxes/vpsfree1/backups.nix

@@ -4,7 +4,7 @@
   ...
 }: let
   genericBackupPath = "/var/lib/backups/";
-  containersBackupPath = "${genericBackupPath}/oci-containers/";
+  nixosContainersBackupPath = "/var/lib/nixos-containers/";
 in rec {
   environment.systemPackages = with pkgs; [restic];
 
@@ -23,24 +23,28 @@ in rec {
         "/var/lib/foundryvtt"
         "/var/lib/gitea"
         "/var/lib/mastodon"
-        "${containersBackupPath}"
+        "${nixosContainersBackupPath}"
       ];
       repository = "b2:cyplo-restic-vpsfree";
       backupPrepareCommand = ''
-        mkdir -p ${containersBackupPath}/
         systemctl stop container@mastodon.service
-        ${pkgs.podman}/bin/podman volume export woodpecker-server-data -o ${containersBackupPath}/woodpecker.tar
       '';
       backupCleanupCommand = ''
         systemctl start container@mastodon.service
       '';
       timerConfig = {OnCalendar = "daily";};
       environmentFile = "${config.sops.secrets.restic-backups-b2-environment.path}";
+      extraBackupArgs = [
+        "--exclude='cache'"
+      ];
     };
   };
 
   systemd.services.restic-backups-b2 = {
-    environment = {GOMAXPROCS = "1";};
+    environment = {
+      GOMAXPROCS = "1";
+      GOGC = "20";
+    };
     serviceConfig = {
       Nice = 19;
       IOSchedulingClass = "idle";