Laravel Transactional Email

SMTP configuration

Use Laravel's SMTP mailer for the lowest-risk migration:

MAIL_MAILER=smtp
MAIL_HOST=smtp.postscale.io
MAIL_PORT=587
MAIL_USERNAME=your-smtp-username
MAIL_PASSWORD=your-smtp-password
MAIL_ENCRYPTION=tls
MAIL_FROM_ADDRESS=alerts@example.com
MAIL_FROM_NAME="Acme"

The From domain still needs SPF, DKIM, and DMARC-compatible records in DNS.

Queue mailables

Laravel mailables can be queued so user requests do not wait on network delivery.

Mail::to($user->email)->queue(new WelcomeMail($user));

Make sure your queue retry policy does not create duplicate one-time links or regenerated receipts. Generate the token or invoice once, then retry sending the same message state.

REST API adapter

For new code, create a service class that posts to the email API. Keep it behind an interface so tests can use a fake sender.

final class TransactionalEmail
{
    public function sendWelcome(User $user): void
    {
        // Build a normalized message and send it through your provider adapter.
    }
}

This structure makes it easier to move from SMTP to REST later.

Webhook state

Laravel should not treat Mail::queue() as delivered. Store message state and update it from delivery webhooks:

1. accepted
2. delivered
3. deferred
4. bounced
5. complained

Use a unique event ID so provider retries do not duplicate side effects.

References

• Laravel Mail documentation
• Laravel Queues documentation
• SMTP relay vs email API
• Webhook retries and idempotency