infra/nix/seattle/configuration.nix

{
  config,
  pkgs,
  ...
}: {
  imports = [
    # Include the results of the hardware scan.
    ./hardware.nix
  ];

  boot = {
    supportedFilesystems = ["nfs"];
    kernelPackages = pkgs.linuxPackages_rpi4;
    kernelParams = ["cgroup_enable=memory" "cgroup_enable=cpuset" "cgroup_memory=1"];
    loader = {
      grub.enable = false;
      generic-extlinux-compatible.enable = true;
    };
  };

  nix = {
    settings = {
      auto-optimise-store = true;
      experimental-features = ["nix-command" "flakes"];
    };
    gc = {
      automatic = true;
      dates = "weekly";
      options = "--delete-older-than 30d";
    };
    # Free up to 1GiB whenever there is less than 100MiB left.
    extraOptions = ''
      min-free = ${toString (100 * 1024 * 1024)}
      max-free = ${toString (1024 * 1024 * 1024)}
    '';
  };

  networking = {
    hostName = "seattle";
    domain = "gmem.ca";
    firewall = {
      trustedInterfaces = ["tailscale0"];
      checkReversePath = "loose";
      allowedTCPPorts = [22 80 443 6443 10250];
      allowedUDPPorts = [41641 80 443];
      enable = false;
    };
    nftables.enable = false;
  };

  time.timeZone = "Europe/London";

  users.users.gsimmer = {
    isNormalUser = true;
    extraGroups = ["wheel"];
    packages = with pkgs; [
      tree
    ];
    openssh.authorizedKeys.keys = let
      authorizedKeys = pkgs.fetchurl {
        url = "https://gmem.ca/ssh";
        hash = "sha256-7PpFDgWVfp26c9PuW+2s3O8MBAODtHr4q7WU/l3BoG4=";
      };
    in
      pkgs.lib.splitString "\n" (builtins.readFile
        authorizedKeys);
  };

  environment.systemPackages = with pkgs; [
    vim
    wget
    htop
    git
    screen
    nix-output-monitor
    tailscale
    nfs-utils
    libraspberrypi
  ];

  services = {
    rpcbind.enable = true;
    openssh.enable = true;
    tailscale.enable = true;
    k3s = {
      enable = true;
      role = "server";
      extraFlags = toString [
        "--secrets-encryption --disable=traefik,servicelb --kube-apiserver-arg service-node-port-range=69-32767"
      ];
    };
  };

  hardware = {
    bluetooth = {
      enable = true;
      powerOnBoot = true;
    };
    raspberry-pi."4".apply-overlays-dtmerge.enable = true;
    deviceTree = {
      enable = true;
      filter = "*rpi-4-*.dtb";
    };
  };

  system.stateVersion = "23.11"; # dId YoU rEaD tHe CoMmEnT?
}