{ ifThen, otherwise }:
let
  relVer = [
    (ifThen "protocol = 'smtp'" "relaxed")
    (otherwise "disable")
  ];
in
{
  dkim = {
    sign = [
      (ifThen "sender_domain = 'pyrox.dev'" "['rsa', 'ed25519']")
      (otherwise false)
    ];
  };
  spf.verify.ehlo = relVer;
  spf.verify.mail-from = relVer;
  dmarc.verify = relVer;
  iprev.verify = relVer;
  arc.seal = "'ed25519'";
  arc.verify = "relaxed";
}