{
  lib,
  vhack,
  pkgs,
  vhackPackages,
  ...
}: let
  server1Domain = "mail.server1";
  server2Domain = "mail.server2";

  common = import ../../../common/email/functions.nix {inherit pkgs vhackPackages;};

  # That's a horrible hack. We should instead wait, until the delivery of the email is
  # confirmed.
  sleepTime = "40";
in
  vhack.runTest {
    name = "email";

    serverDomains = [
      {server1 = server1Domain;}
      {server2 = server2Domain;}
    ];

    nodes = {
      server1 = common.mkMailServer server1Domain "alice";
      server2 = common.mkMailServer server2Domain "bob";

      alice = common.mkUser "alice" server1Domain;
      bob = common.mkUser "bob" server2Domain;
    };

    dns = {
      server1 = common.mkDnsZone server1Domain;
      server2 = common.mkDnsZone server2Domain;
    };

    services = [
      {server1 = "postfix.service";}
      {server1 = "dovecot.service";}
      {server2 = "postfix.service";}
      {server2 = "dovecot.service";}

      {alice = "multi-user.target";}
      {bob = "multi-user.target";}
    ];

    ports = [
      {server1 = 993;} # imap
      {server1 = 465;} # smtp

      {server2 = 993;} # imap
      {server2 = 465;} # smtp
    ];

    testScript = {...}:
    # Python
    ''
      from time import sleep

      with subtest("Dkim keys work"):
        server1.succeed("sudo -u rspamd ${pkgs.writeShellScript "dkim-keys-check" ''
        set -xe

        stat /run/agenix/mailDkim

        ${lib.getExe pkgs.openssl} pkey -text -noout -in /run/agenix/mailDkim | grep Private-Key
        ${lib.getExe pkgs.openssl} pkey -text -noout -in /run/agenix/mailDkim
      ''}")

      with subtest("Both start without mail"):
        alice.succeed("sudo -u alice ${common.scripts.expectNoNewMail}")
        bob.succeed("sudo -u bob ${common.scripts.expectNoNewMail}")


        with subtest("Alice can send an empty email to bob"):
          alice.succeed("sudo -u alice ${pkgs.writeShellScript "alice-send" ''
        set -xe

        echo "" | msmtp --debug --account alice bob@${server2Domain} >&2
      ''}")

        # Give the mail server some time to send the email.
        sleep(${sleepTime})

        bob.succeed("sudo -u bob ${common.scripts.expectNewSpamMail}")

      with subtest("Alice can send an non-empty email to bob"):
        alice.succeed("sudo -u alice ${pkgs.writeShellScript "alice-send" ''
        set -xe

        cat << EOF | msmtp --debug --account alice bob@${server2Domain} >&2
        Subject: Hi bob, I'm Alice!

        Good day, Bob!

        This is an email.
        It contains a subject and a body.
        I also assert utf8 support by including my last name in this very message.

        XOXO
        Alice van Dåligen.

        .
        EOF
      ''}")

        # Give the mail server some time to send the email.
        sleep(${sleepTime})

        bob.succeed("sudo -u bob ${common.scripts.expectNewSpamMail}")

      with subtest("Bob can send an email to alice"):
        bob.succeed("sudo -u bob ${pkgs.writeShellScript "bob-send" ''
        set -xe

        cat << EOF | msmtp --debug --account bob alice@${server1Domain} >&2
        Hi Alice!

        Thank you for your emails! (Although they seemed kinda weird tbh :?)

        XXX
        Bob Älšter

        .
        EOF
      ''}")

        # Give the mail server some time to send the email.
        sleep(${sleepTime})

        alice.succeed("sudo -u alice ${common.scripts.expectNewSpamMail}")
    '';
  }