{
  programs.aria2 = {
    enable = true;

    settings = {
      listen-port = 60000;
      dht-listen-port = 60000;
      seed-ratio = 1.0;
      max-upload-limit = "50K";
      ftp-pasv = true;
    };

    extraConfig = ''
      # Extra aria2 configuration.
    '';
  };

  nmt.script = ''
    assertFileContent \
      home-files/.config/aria2/aria2.conf \
      ${builtins.toFile "aria2-expected-config.conf" ''
        dht-listen-port=60000
        ftp-pasv=true
        listen-port=60000
        max-upload-limit=50K
        seed-ratio=1.000000
        # Extra aria2 configuration.
      ''}
  '';
}
