Your Email.
Your Server.

# Inbound path (MX → Port 25)
Internet → DNS MX → :25 (SMTP)
         → MIME parse
         → mail_addresses lookup
         → save .eml + SQLite row
         → check forward_to → queue outbox

# Outbound path (Port 587)
App/PHP → :587 SMTP AUTH (panel user)
        → Rcpt check (local or relay)
        → insert outbox row
        → processOutbox() every 10s
          → MX lookup OR SMTP relay
          → mark sent / retry on fail

# PHP mail() bridge
sendmail_path = "/usr/bin/msmtp -t"
host = 127.0.0.1  port = 25
      

use PHPMailer\PHPMailer\PHPMailer;

$mail = new PHPMailer(true);

// Connect to local onifast-mail
$mail->isSMTP();
$mail->Host       = '127.0.0.1';
$mail->SMTPAuth   = true;
$mail->Username   = 'your_panel_user';
$mail->Password   = 'your_password';
$mail->Port       = 587;

$mail->setFrom('hello@yourdomain.com');
$mail->addAddress('user@external.com');

$mail->isHTML(true);
$mail->Subject = 'Hello from Onifast Mail!';
$mail->Body    = '<p>Sent via local MTA.</p>';
$mail->send();