flake.lock

@@ -20,6 +20,21 @@
         "type": "github"
       }
     },
+    "impermanence": {
+      "locked": {
+        "lastModified": 1737831083,
+        "narHash": "sha256-LJggUHbpyeDvNagTUrdhe/pRVp4pnS6wVKALS782gRI=",
+        "owner": "nix-community",
+        "repo": "impermanence",
+        "rev": "4b3e914cdf97a5b536a889e939fb2fd2b043a170",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-community",
+        "repo": "impermanence",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1761114652,
@@ -39,6 +54,7 @@
     "root": {
       "inputs": {
         "home-manager": "home-manager",
+        "impermanence": "impermanence",
         "nixpkgs": "nixpkgs"
       }
     }

flake.nix

@@ -5,10 +5,11 @@
     nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable/";
     home-manager.url = "github:nix-community/home-manager";
     home-manager.inputs.nixpkgs.follows = "nixpkgs";
+    impermanence.url = "github:nix-community/impermanence";
   };
 
   outputs =
-    { self, nixpkgs, home-manager, ... } @ inputs:
+    { self, nixpkgs, impermanence, home-manager, ... } @ inputs:
     let
       system = "x86_64-linux";
       username = "xory";
@@ -19,6 +20,7 @@
 	  modules = [
       ./hosts/${hostName}/configuration.nix
 	    ./hosts/${hostName}/hardware-configuration.nix
+      impermanence.nixosModules.impermanence
 
 	    home-manager.nixosModules.home-manager {
 	      home-manager.useGlobalPkgs = true;

hosts/voidspear/configuration.nix

@@ -40,6 +40,37 @@
     LC_TIME = "en_GB.UTF-8";
   };
 
+  # Impermanence
+
+  fileSystems."/" = {
+    device = "none";
+    fsType = "tmpfs";
+    neededForBoot = true;
+  };
+
+  fileSystems."/persist" = {
+    device = "/dev/disk/by-uuid/1578f380-e588-419b-ace0-f63e6a48ca39";
+    fsType = "ext4";
+    neededForBoot = true;
+  };
+
+  environment.persistence."/persist" = {
+    hideMounts = true;
+    directories = [
+      "/nix"
+      "/home"
+      "/var/log"
+      "/var/lib/bluetooth"
+      "/etc/NetworkManager/system-connections"
+      "/var/lib/nixos"
+    ];
+  };
+
+  environment.etc."machine-id" = {
+    source = "/persist/etc/machine-id";
+    mode = "0444";
+  };
+
   # Define a user account. Don't forget to set a password with ‘passwd’.
   programs.zsh.enable = true; # home-manager already installs this but nixos complains w/o it 
   users.users.xory = {

hosts/voidspear/hardware-configuration.nix

@@ -13,10 +13,10 @@
   boot.kernelModules = [ "kvm-amd" ];
   boot.extraModulePackages = [ ];
 
-  fileSystems."/" =
-    { device = "/dev/disk/by-uuid/1578f380-e588-419b-ace0-f63e6a48ca39";
-      fsType = "ext4";
-    };
+  # fileSystems."/" =
+    # { device = "/dev/disk/by-uuid/1578f380-e588-419b-ace0-f63e6a48ca39";
+      # fsType = "ext4";
+    # };
 
   fileSystems."/boot" =
     { device = "/dev/disk/by-uuid/4CB1-40B6";