# Single-disk ZFS layout for the Topton's 256GB mSATA SSD: vfat ESP for boot,
# the rest a zpool (zstd compression, no atime). Single disk = no redundancy;
# ZFS buys us compression, snapshots, and checksumming. Requires
# networking.hostId (set in configuration.nix). The device is a placeholder:
# boot the installer, read the real id from `ls -l /dev/disk/by-id/`, and fill
# it in before `clan machines install`. Changing the layout later requires
# wiping and reinstalling.
{

  boot.loader.grub.efiSupport = true;
  boot.loader.grub.efiInstallAsRemovable = true;
  boot.loader.grub.enable = true;
  disko.devices = {
    disk = {
      main = {
        name = "main-gw-cnx-1";
        device = "/dev/disk/by-id/CHANGE-ME-msata-ssd";
        type = "disk";
        content = {
          type = "gpt";
          partitions = {
            "boot" = {
              size = "1M";
              type = "EF02"; # for grub MBR
              priority = 1;
            };
            ESP = {
              type = "EF00";
              size = "500M";
              content = {
                type = "filesystem";
                format = "vfat";
                mountpoint = "/boot";
                mountOptions = [ "umask=0077" ];
              };
            };
            zfs = {
              size = "100%";
              content = {
                type = "zfs";
                pool = "rpool";
              };
            };
          };
        };
      };
    };
    zpool = {
      rpool = {
        type = "zpool";
        options.ashift = "12";
        rootFsOptions = {
          compression = "zstd";
          acltype = "posixacl";
          xattr = "sa";
          atime = "off";
          mountpoint = "none";
        };
        datasets = {
          root = {
            type = "zfs_fs";
            mountpoint = "/";
          };
          nix = {
            type = "zfs_fs";
            mountpoint = "/nix";
          };
          # Service state (Omada, Kea leases, CrowdSec db, journald) — its own
          # dataset so it can be snapshotted/sent independently of the OS.
          var = {
            type = "zfs_fs";
            mountpoint = "/var";
          };
        };
      };
    };
  };
}