init

hosts/chunk/hardware-configuration.nix

@@ -22,9 +22,10 @@
   boot.kernelModules = [ "kvm-intel" ];
   boot.extraModulePackages = [ ];
 
-  fileSystems."/" = {
+  fileSystems."/persistent" = {
     device = "/dev/disk/by-uuid/6fff5dd4-8d7a-43fa-85be-eec74ef2089e";
     fsType = "ext4";
+    neededForBoot = true;
   };
 
   swapDevices = [ ];

hosts/chunk/impermanence.nix

@@ -0,0 +1,20 @@
+{...}: {
+  environment.persistence."/persistent" = {
+    enable = true;
+    hideMounts = true;
+    directories = [
+      "/var/log"
+      "/opt"
+      "/var/lib"
+
+      "/root/.config/borg" # nonce
+      # used a hack to disable cache
+      # see https://borgbackup.readthedocs.io/en/stable/faq.html#the-borg-cache-eats-way-too-much-disk-space-what-can-i-do
+      "/root/.cache/borg"
+      "/root/.config/sops"
+    ];
+    files = [
+      "/etc/machine-id"
+    ];
+  };
+}