{ ... }:

# Declarative OS-disk layout (disko). UEFI: GPT with an ESP + ext4 root.
# disko both PARTITIONS/FORMATS this disk and generates the NixOS
# `fileSystems.*` entries, so hardware-configuration.nix must NOT define
# fileSystems for "/" or "/boot".
#
# ⚠️  This disk is WIPED on install. Set `device` to the OS disk ONLY.
#     Your NAS data disk is NOT listed here — keep it out of disko so it is
#     never formatted; mount it as a plain read-write fileSystem instead
#     (see configuration.nix, /mnt/data).
#
# Find the stable id:  ls -l /dev/disk/by-id   (use by-id, never /dev/sdX)
{
  disko.devices.disk.os = {
    type = "disk";
    device = "/dev/disk/by-id/CHANGE-ME-os-disk";
    content = {
      type = "gpt";
      partitions = {
        ESP = {
          size = "512M";
          type = "EF00";
          content = {
            type = "filesystem";
            format = "vfat";
            mountpoint = "/boot";
            mountOptions = [ "umask=0077" ];
          };
        };
        root = {
          size = "100%";
          content = {
            type = "filesystem";
            format = "ext4";
            mountpoint = "/";
          };
        };
      };
    };
  };
}