{ pkgs, config, ... }:
{
  # Monitoring
  services.netdata.enable = true;
  systemd.services.netdata.restartTriggers = map (name: config.environment.etc."netdata/${name}.conf".source) [
    "health_alarm_notify"
    "stream"
    "fping"
  ];
  environment.etc."netdata/stream.conf" = {
    user = "netdata";
    group = "netdata";
    mode = "0600";
    text = ''
      # hackens-desktop
      [074e699a-4206-4e13-baa7-e4524326f1e0]
        enabled = yes
        default history = 3600
        default memory mode = dbengine
        health enabled by default = auto
        allow from = 192.168.1.117, 2001:470:1f13:21d:49fd:1d82:d2ff:d868

      # hackens-openwrt
      [cab3fe1e-576b-420d-b301-84308e44f340]
        enabled = yes
        default history = 3600
        default memory mode = dbengine
        health enabled by default = auto
        allow from = 192.168.1.1, 2001:470:1f13:21d::1
    '';
  };
  environment.etc."netdata/health_alarm_notify.conf" = {
    user = "netdata";
    group = "netdata";
    mode = "0600";
    text = ''
      # External tools
      nc="${pkgs.netcat}/bin/nc"

      # IRC configuration
      SEND_IRC="YES"
      DEFAULT_RECIPIENT_IRC="#hackens-status"
      IRC_NETWORK="ens.wtf"
      IRC_NICKNAME="hackens"
      IRC_REALNAME="hackENS netdata monitoring"
    '';
  };
  environment.etc."netdata/fping.conf" = {
    user = "netdata";
    group = "netdata";
    mode = "0600";
    text = ''
      fping="${pkgs.fping}/bin/fping"
      hosts="hackens.org hack.ens.fr sas.eleves.ens.fr argonaut.ens.wtf clipper.ens.fr merle.eleves.ens.fr"
    '';
  };
  services.smartd.enable = true;
  services.smartd.extraOptions = [ "-A /var/log/smartd/" ]; # For netdata.

  # MQTT for every usage, notably OctoPrint events.
  services.mosquitto = {
    enable = true;
    listeners = [
      {
        address = "192.168.1.118";
      }
    ];
    settings = {
      # allow_anonymous = true;
    };
  };
}