configurations/nixos/defiant/configuration.nix

@@ -67,6 +67,7 @@
   };
 
   storage = {
+    generateBase = false;
     zfs = {
       enable = true;
       notifications = {

configurations/nixos/defiant/default.nix

@@ -4,6 +4,7 @@
     ./hardware-configuration.nix
     ./configuration.nix
     ./packages.nix
+    ./legacy-storage.nix
     ./legacy-impermanence.nix
   ];
 }

configurations/nixos/defiant/legacy-impermanence.nix

@@ -14,7 +14,17 @@
   ...
 }: {
   config = lib.mkIf config.storage.impermanence.enable {
-    environment.persistence."/persist/replicate/system/root" = {
+    system.activationScripts = {
+      "var-lib-private-permissions" = {
+        deps = ["specialfs"];
+        text = ''
+          mkdir -p /persist/system/root/var/lib/private
+          chmod 0700 /persist/system/root/var/lib/private
+        '';
+      };
+    };
+
+    environment.persistence."/persist/system/root" = {
       enable = true;
       hideMounts = true;
       directories = lib.mkMerge [
@@ -78,7 +88,7 @@
           }
         ])
 
-        # Jellyfin
+        # Jellyfin (data/cache only - media is on separate dataset)
         (lib.mkIf config.services.jellyfin.enable [
           {
             directory = "/var/lib/jellyfin";
@@ -90,12 +100,6 @@
             user = "jellyfin";
             group = "jellyfin";
           }
-          {
-            directory = config.services.jellyfin.media_directory;
-            user = "jellyfin";
-            group = "jellyfin_media";
-            mode = "1770";
-          }
         ])
 
         # Immich
@@ -152,19 +156,13 @@
           }
         ])
 
-        # qBittorrent
+        # qBittorrent (config only - media is on separate dataset)
         (lib.mkIf config.services.qbittorrent.enable [
           {
             directory = "/var/lib/qBittorrent/";
             user = "qbittorrent";
             group = "qbittorrent";
           }
-          {
-            directory = config.services.qbittorrent.mediaDir;
-            user = "qbittorrent";
-            group = "qbittorrent";
-            mode = "1775";
-          }
         ])
 
         # Sonarr
@@ -222,5 +220,42 @@
         ])
       ];
     };
+
+    # Jellyfin media on separate dataset (matching main)
+    environment.persistence."/persist/system/jellyfin" = lib.mkIf config.services.jellyfin.enable {
+      enable = true;
+      hideMounts = true;
+      directories = [
+        {
+          directory = config.services.jellyfin.media_directory;
+          user = "jellyfin";
+          group = "jellyfin_media";
+          mode = "1770";
+        }
+      ];
+    };
+
+    # qBittorrent media on separate dataset (matching main)
+    environment.persistence."/persist/system/qbittorrent" = lib.mkIf config.services.qbittorrent.enable {
+      enable = true;
+      hideMounts = true;
+      directories = [
+        {
+          directory = config.services.qbittorrent.mediaDir;
+          user = "qbittorrent";
+          group = "qbittorrent";
+          mode = "1775";
+        }
+      ];
+    };
+
+    # /var/log persistence (matching main)
+    environment.persistence."/persist/system/var/log" = {
+      enable = true;
+      hideMounts = true;
+      directories = [
+        "/var/log"
+      ];
+    };
   };
 }

configurations/nixos/defiant/legacy-storage.nix

@@ -0,0 +1,103 @@
+# Legacy storage configuration for defiant
+# This file manually defines ZFS datasets matching the main branch structure
+# to allow incremental migration to the new storage module.
+#
+# Datasets from main branch:
+# - local/                    - ephemeral parent
+# - local/home/leyla          - ephemeral user home
+# - local/system/nix          - nix store
+# - local/system/root         - root filesystem (rolled back on boot)
+# - local/system/sops         - sops age key
+# - persist/                  - persistent parent
+# - persist/home/leyla        - persistent user home
+# - persist/system/jellyfin   - jellyfin media
+# - persist/system/qbittorrent - qbittorrent media
+# - persist/system/root       - persistent root data
+# - persist/system/var/log    - log persistence
+{lib, ...}: {
+  # Manually define ZFS datasets matching main's structure
+  storage.zfs.datasets = {
+    # Ephemeral datasets (local/)
+    "local" = {
+      type = "zfs_fs";
+      mount = null;
+    };
+    "local/home/leyla" = {
+      type = "zfs_fs";
+      mount = "/home/leyla";
+      snapshot = {
+        blankSnapshot = true;
+      };
+    };
+    "local/system/nix" = {
+      type = "zfs_fs";
+      mount = "/nix";
+      atime = "off";
+      relatime = "off";
+      snapshot = {
+        autoSnapshot = false;
+      };
+    };
+    "local/system/root" = {
+      type = "zfs_fs";
+      mount = "/";
+      snapshot = {
+        blankSnapshot = true;
+      };
+    };
+    "local/system/sops" = {
+      type = "zfs_fs";
+      mount = "/persist/sops";
+    };
+
+    # Persistent datasets (persist/)
+    "persist" = {
+      type = "zfs_fs";
+      mount = null;
+    };
+    "persist/home/leyla" = {
+      type = "zfs_fs";
+      mount = "/persist/home/leyla";
+      snapshot = {
+        autoSnapshot = true;
+      };
+    };
+    "persist/system/jellyfin" = {
+      type = "zfs_fs";
+      mount = "/persist/system/jellyfin";
+      atime = "off";
+      relatime = "off";
+    };
+    "persist/system/qbittorrent" = {
+      type = "zfs_fs";
+      mount = "/persist/system/qbittorrent";
+      atime = "off";
+      relatime = "off";
+    };
+    "persist/system/root" = {
+      type = "zfs_fs";
+      mount = "/persist/system/root";
+      snapshot = {
+        autoSnapshot = true;
+      };
+    };
+    "persist/system/var/log" = {
+      type = "zfs_fs";
+      mount = "/persist/system/var/log";
+    };
+  };
+
+  # Boot commands to rollback ephemeral root on boot
+  boot.initrd.postResumeCommands = lib.mkAfter ''
+    zfs rollback -r rpool/local/system/root@blank
+  '';
+
+  # FileSystems needed for boot
+  fileSystems = {
+    "/".neededForBoot = true;
+    "/persist/system/root".neededForBoot = true;
+    "/persist/system/var/log".neededForBoot = true;
+    "/persist/system/jellyfin".neededForBoot = true;
+    "/persist/system/qbittorrent".neededForBoot = true;
+  };
+}

flake.lock

@@ -129,20 +129,12 @@
       }
     },
     "impermanence": {
-      "inputs": {
-        "home-manager": [
-          "home-manager"
-        ],
-        "nixpkgs": [
-          "nixpkgs"
-        ]
-      },
       "locked": {
-        "lastModified": 1767822991,
+        "lastModified": 1737831083,
-        "narHash": "sha256-iyrn9AcPZCoyxX4OT8eMkBsjG7SRUQXXS/V1JzxS7rA=",
+        "narHash": "sha256-LJggUHbpyeDvNagTUrdhe/pRVp4pnS6wVKALS782gRI=",
         "owner": "nix-community",
         "repo": "impermanence",
-        "rev": "82e5bc4508cab9e8d5a136626276eb5bbce5e9c5",
+        "rev": "4b3e914cdf97a5b536a889e939fb2fd2b043a170",
         "type": "github"
       },
       "original": {

modules/nixos-modules/storage/impermanence.nix

@@ -66,10 +66,11 @@ in {
         }
       ];
 
-      # fixes issues with /var/lib/private not having the correct permissions https://github.com/nix-community/impermanence/issues/254
-      system.activationScripts."createPersistentStorageDirs".deps = ["var-lib-private-permissions" "users" "groups"];
       system.activationScripts = {
-        "var-lib-private-permissions" = {
+        # fixes issues with /var/lib/private not having the correct permissions https://github.com/nix-community/impermanence/issues/254
+        "createPersistentStorageDirs".deps = ["var-lib-private-permissions" "users" "groups"];
+
+        "var-lib-private-permissions" = lib.mkIf config.storage.generateBase {
           deps = ["specialfs"];
           text = ''
             mkdir -p /persist/replicate/system/root/var/lib/private

modules/nixos-modules/storage/storage.nix

@@ -22,7 +22,16 @@ args @ {
   # Find options that are only in impermanence datasets (not in regular ZFS datasets)
   impermanenceOnlyOptions = lib.lists.subtractLists regularDatasetOptions impermanenceDatasetOptions;
 in {
-  options.storage.datasets = {
+  options.storage = {
+    generateBase = lib.mkOption {
+      type = lib.types.bool;
+      default = true;
+      description = ''
+        When enabled, enables automatic generation of base datasets (ephemeral, local, replicate roots).
+        This allows manual definition of datasets matching an existing system layout for migration purposes.
+      '';
+    };
+    datasets = {
       ephemeral = lib.mkOption {
         type = lib.types.attrsOf (lib.types.submodule datasetSubmodule);
         default = {};
@@ -36,9 +45,10 @@ in {
         default = {};
       };
     };
+  };
 
   config = lib.mkMerge [
-    (lib.mkIf config.storage.zfs.enable {
+    (lib.mkIf (config.storage.zfs.enable && config.storage.generateBase) {
       # Create ZFS datasets based on storage.datasets configuration
       storage.datasets = {
         local = {
@@ -55,7 +65,7 @@ in {
         };
       };
     })
-    (lib.mkIf (config.storage.zfs.enable && config.storage.impermanence.enable) {
+    (lib.mkIf (config.storage.zfs.enable && config.storage.impermanence.enable && config.storage.generateBase) {
       storage.datasets = {
         ephemeral = {
           "" = {