refactor(viridian): migrate service data to dedicated BTRFS subvolumes

Migrate from path-based persistence (/persist/var/lib/*) to dedicated
BTRFS subvolumes for better data isolation and snapshot capabilities.

- Move valuable user-facing services to /srv/* with srv-* subvolumes:
  - forgejo: git repositories and database
  - opengist: paste data
  - minecraft: game world data
  - lighttpd: static web content
  - containers: OCI container volumes

- Update home directory to use hm-sajenim subvolume on viridian disk
- Remove jupyterhub service (no longer in use)
- Update borgbackup paths to match new service locations
- Follow upstream service defaults where possible for maintainability

Services kept on /persist (disposable state):
- traefik, crowdsec, murmur

nixos/common/users/sajenim/default.nix

@@ -4,7 +4,9 @@
   pkgs,
   config,
   ...
-}: {
+}: let
+  hostname = config.networking.hostName;
+in {
   imports = [
     inputs.home-manager.nixosModules.home-manager
   ];
@@ -29,8 +31,8 @@
   };
 
   fileSystems."/home/sajenim" = {
-    device = "/dev/disk/by-label/data";
+    device = "/dev/disk/by-label/${hostname}";
     fsType = "btrfs";
-    options = ["subvol=sajenim" "compress=zstd"];
+    options = ["subvol=hm-sajenim" "compress=zstd"];
   };
 }

nixos/viridian/hardware-configuration.nix

@@ -52,17 +52,6 @@
     fsType = "vfat";
   };
 
-  fileSystems."/srv/multimedia" = {
-    device = "/dev/disk/by-label/multimedia";
-    fsType = "ext4";
-  };
-
-  fileSystems."/srv/multimedia/containers" = {
-    device = "/dev/disk/by-label/data";
-    fsType = "btrfs";
-    options = ["subvol=containers" "compress=zstd"];
-  };
-
   swapDevices = [
     {
       device = "/swap/swapfile";

nixos/viridian/multimedia/default.nix

@@ -1,4 +1,6 @@
-{...}: {
+{config, ...}: let
+  hostname = config.networking.hostName;
+in {
   imports = [
     ./jellyfin
     ./lidarr
@@ -7,4 +9,17 @@
     ./radarr
     ./sonarr
   ];
+
+  fileSystems = {
+    "/srv/multimedia" = {
+      device = "/dev/disk/by-label/multimedia";
+      fsType = "ext4";
+    };
+
+    "/srv/multimedia/containers" = {
+      device = "/dev/disk/by-label/${hostname}";
+      fsType = "btrfs";
+      options = ["subvol=srv-containers" "compress=zstd"];
+    };
+  };
 }

nixos/viridian/services/borgbackup/default.nix

@@ -6,14 +6,13 @@
   services.borgbackup.jobs."borgbase" = {
     paths = [
       # Websites
-      "/srv/www/sajenim.dev"
+      "/srv/lighttpd/sajenim.dev"
       # Services
       "/var/lib/crowdsec"
       "/var/lib/forgejo"
-      "/var/lib/jupyterhub"
-      "/var/lib/minecraft"
       "/var/lib/opengist"
       "/var/lib/traefik"
+      "/srv/minecraft"
       # Multimedia
       "/srv/multimedia/containers/jellyfin"
       "/srv/multimedia/containers/lidarr"

nixos/viridian/services/default.nix

@@ -4,7 +4,6 @@
     ./crowdsec
     ./forgejo
     ./inspircd
-    ./jupyterhub
     ./lighttpd
     ./minecraft
     ./mpd

nixos/viridian/services/forgejo/default.nix

@@ -1,7 +1,9 @@
-{config, ...}: {
+{config, ...}: let
+  hostname = config.networking.hostName;
+in {
   services.forgejo = {
     enable = true;
-    stateDir = "/var/lib/forgejo";
+    stateDir = "/srv/forgejo";
     settings = {
       server = {
         DOMAIN = "git.sajenim.dev";
@@ -32,13 +34,12 @@
     ];
   };
 
-  environment.persistence."/persist" = {
+  fileSystems."/srv/forgejo" = {
-    directories = [
+    device = "/dev/disk/by-label/${hostname}";
-      {
+    fsType = "btrfs";
-        directory = "/var/lib/forgejo";
+    options = [
-        user = "forgejo";
+      "subvol=srv-forgejo"
-        group = "forgejo";
+      "compress=zstd"
-      }
     ];
   };
 }

nixos/viridian/services/jupyterhub/default.nix

@@ -1,31 +0,0 @@
-{config, ...}: {
-  services.jupyterhub = {
-    enable = true;
-    port = 9475;
-    extraConfig = ''
-      c.Authenticator.allowed_users = {'sajenim'}
-    '';
-  };
-
-  services.traefik.dynamicConfigOptions.http.routers = {
-    jupyter = {
-      rule = "Host(`jupyter.home.arpa`)";
-      entryPoints = [
-        "websecure"
-      ];
-      service = "jupyter";
-    };
-  };
-
-  services.traefik.dynamicConfigOptions.http.services = {
-    jupyter.loadBalancer.servers = [
-      {url = "http://127.0.0.1:${toString config.services.jupyterhub.port}";}
-    ];
-  };
-
-  environment.persistence."/persist" = {
-    directories = [
-      "/var/lib/jupyterhub"
-    ];
-  };
-}

nixos/viridian/services/lighttpd/default.nix

@@ -1,8 +1,10 @@
-{config, ...}: {
+{config, ...}: let
+  hostname = config.networking.hostName;
+in {
   services.lighttpd = {
     enable = true;
     port = 5624;
-    document-root = "/srv/www/sajenim.dev";
+    document-root = "/srv/lighttpd/sajenim.dev";
   };
 
   services.traefik.dynamicConfigOptions.http.routers = {
@@ -21,13 +23,12 @@
     ];
   };
 
-  environment.persistence."/persist" = {
+  fileSystems."/srv/lighttpd" = {
-    directories = [
+    device = "/dev/disk/by-label/${hostname}";
-      {
+    fsType = "btrfs";
-        directory = "/srv/www";
+    options = [
-        user = "lighttpd";
+      "subvol=srv-lighttpd"
-        group = "lighttpd";
+      "compress=zstd"
-      }
     ];
   };
 }

nixos/viridian/services/minecraft/default.nix

@@ -5,6 +5,7 @@
   config,
   ...
 }: let
+  hostname = config.networking.hostName;
   modpack = pkgs.fetchPackwizModpack rec {
     version = "9083262";
     url = "https://raw.githubusercontent.com/sajenim/minecraft-modpack/${version}/pack.toml";
@@ -71,9 +72,6 @@ in {
       };
     };
 
-    # Each server will be under a subdirectory named after the server name.
-    dataDir = "/var/lib/minecraft";
-
     # Open firewall for all servers.
     openFirewall = true;
     
@@ -106,14 +104,12 @@ in {
     };
   };
 
-  # Enable persistence for the data directory.
+  fileSystems."/srv/minecraft" = {
-  environment.persistence."/persist" = {
+    device = "/dev/disk/by-label/${hostname}";
-    directories = [
+    fsType = "btrfs";
-      {
+    options = [
-        directory = "/var/lib/minecraft";
+      "subvol=srv-minecraft"
-        user = "minecraft";
+      "compress=zstd"
-        group = "minecraft";
-      }
     ];
   };
 }

nixos/viridian/services/opengist/default.nix

@@ -1,4 +1,5 @@
-{...}: let
+{config, ...}: let
+  hostname = config.networking.hostName;
   port = "6157";
 in {
   # OpenGist service configuration
@@ -9,7 +10,7 @@ in {
         "${port}:${port}"
       ];
       volumes = [
-        "/var/lib/opengist:/opengist"
+        "/srv/opengist:/opengist"
       ];
       # Environment variables for OpenGist
       environment = {
@@ -43,20 +44,18 @@ in {
     };
   };
 
-  # Persist data for OpenGist
-  environment.persistence."/persist" = {
-    directories = [
-      {
-        directory = "/var/lib/opengist";
-        user = "sajenim";
-        group = "users";
-      }
-    ];
-  };
-
   # Activation script to create symlinks for custom assets
   system.activationScripts.opengist-symlink = ''
-    cp ${toString ./assets/pikachu.png} /var/lib/opengist/custom/pikachu.png
+    cp ${toString ./assets/pikachu.png} /srv/opengist/custom/pikachu.png
-    cp ${toString ./assets/pokeball.png} /var/lib/opengist/custom/pokeball.png
+    cp ${toString ./assets/pokeball.png} /srv/opengist/custom/pokeball.png
   '';
+
+  fileSystems."/srv/opengist" = {
+    device = "/dev/disk/by-label/${hostname}";
+    fsType = "btrfs";
+    options = [
+      "subvol=srv-opengist"
+      "compress=zstd"
+    ];
+  };
 }