I understand that mailgun or sendgrid can be used with Flarum as well as it's built in PHP mail. I have an issue with that. I don't want to pay for mailgun or sendgrid because I expect a high amount of false signups by bots.
What's the right way to do this and not use sendgrid or mailgun. I'm not going to pay 500$ a month for mail to bots when I could just pay 5$ or 10 and have a mail server on DigitalOcean.