(untested) config for stinky and diff script.

common/impermanence-tmpfs.nix

@@ -0,0 +1,30 @@
+{
+  lib,
+  config,
+  ...
+}:
+{
+  # Impermanence configuration for tmpfs root filesystem
+  # Used for systems with tmpfs root (e.g., Raspberry Pi with SD card)
+  # Root is in-memory and wiped on every boot
+  # Persistent data is stored in /nix/persist (directory on the /nix partition)
+
+  # Import common impermanence configuration
+  imports = [ ./impermanence-common.nix ];
+
+  config = {
+    # Use /nix/persist for tmpfs-based impermanence
+    custom.impermanence.persistPath = "/nix/persist";
+
+    # tmpfs root filesystem
+    fileSystems."/" = {
+      device = "none";
+      fsType = "tmpfs";
+      options = [
+        "defaults"
+        "size=2G"
+        "mode=755"
+      ];
+    };
+  };
+}