{
  config,
  lib,
  ...
}: let
  inherit
    (lib)
    mkIf
    mkEnableOption
    ;
  cfg = config.services.mathebau-borgbackup;
in {
  imports = [];

  options.services.mathebau-borgbackup = {
    enable = mkEnableOption "mathebau borgbackup service";
  };

  config = mkIf cfg.enable {
    services.borgbackup = {
      # repos are made available at ssh://borg@hostname and served according to the presented ssh-key
      repos = {
        aphoom-zhah = {
          authorizedKeysAppendOnly = [
            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIA8pI6uinXezAMH4vG2yEbu/yOYU5vXcsZN74tYgV+Wj Aphoom-Zhah Backup"
          ];
          path = "/var/lib/backups/aphoom-zhah";
          # subrepos are allowed because each vm creates at least one repo below this filepath and yibb-tstll even more
          allowSubRepos = true;
        };
        azathoth = {
          authorizedKeysAppendOnly = [
            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIGBEwllQ77ktoirXX6dJ6ET8TfK4lzq0aaq+X4rrX2Vk Azathoth Backup"
          ];
          path = "/var/lib/backups/azathoth";
          allowSubRepos = true;
        };
        cthulhu = {
          authorizedKeysAppendOnly = [
            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIMSJl1MvabUADTdOCgufsBzn1tIIpxMq4iDcYZsaW1lV Cthulhu Backup"
          ];
          path = "/var/lib/backups/cthulhu";
          allowSubRepos = true;
        };
        dagon = {
          authorizedKeysAppendOnly = [
            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIJaTBennwqT9eB43gVD1nM1os3dMPZ8RWwIKPEjqMK5V Dagon Backup"
          ];
          path = "/var/lib/backups/dagon";
          allowSubRepos = true;
        };
        eihort = {
          authorizedKeysAppendOnly = [
            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIHLoDxtY4Tp6NKxLt9oHmWT6w4UpU6eA1TnPU2Ut83BN Eihort Backup"
          ];
          path = "/var/lib/backups/eihort";
          allowSubRepos = true;
        };
        hastur = {
          authorizedKeysAppendOnly = [
            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAILeDvTyOUdIPARatX0PPhHgrV1gjERWLt2Twa8E2GETb Hastur Backupsystem"
          ];
          path = "/var/lib/backups/hastur";
          allowSubRepos = true;
        };
        ithaqua = {
          authorizedKeysAppendOnly = [
            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIPJmBf8cz3FTDdeuxWbp1MO2yPT5rvH8ZIGUzfogjpXi Ithaqua Backup"
          ];
          path = "/var/lib/backups/ithaqua";
          allowSubRepos = true;
        };
        sanctamariamaterdei = {
          authorizedKeysAppendOnly = [
            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIH9Le5OI4ympQ0mQKYHmxgxGF598rzpD5VVpWK1mGfd8 Sanctamariamaterdei Backupsystem"
          ];
          path = "/var/lib/backups/sanctamariamaterdei";
          allowSubRepos = true;
        };
        tsathoggua = {
          authorizedKeysAppendOnly = [
            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIKS9/1lFOhv+3sNuGcysM3TYh2xRrjMeAZX3K7CBx0QW Tsathoggua Backup"
          ];
          path = "/var/lib/backups/tsathoggua";
          allowSubRepos = true;
        };
        uvhash = {
          authorizedKeysAppendOnly = [
            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIB8DjIqgFgmYhQnTLpbqL0r7xBPb8TPy6SO5RhQ31OGj Uvhash Backup"
          ];
          path = "/var/lib/backups/uvhash";
          allowSubRepos = true;
        };
        yibb-tstll = {
          authorizedKeysAppendOnly = [
            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAINlnGOV58Ks9lu+WTI4F7QAHtDrJq2jY8ZocITZG8K0+ Yibb-Tstll Backup"
          ];
          path = "/var/lib/backups/yibb-tstll";
          allowSubRepos = true;
        };
      };
    };
  };
}