This is a fun hack, but there is no way I would get involved in providing any form of commercial email service for $1440 arr. I wouldn't do it for $1440 a _day_. Everything involved with email is pain. I wish you luck.
Wish I'd seen this comment 4 years ago.
Agree. Even if you comply with most important technical standards/requirements you still need to spend a lot of time overseeing your system, and researching best practices and recommendations that directly affect domain and IP reputation, to avoid getting blacklisted.
Shameless plug: A while ago I decided to try build a home made SMPT Mail submission component for better understating what's going on under the hoods (and for "fun"), it was really though, and once I was able to send a DKIM verifyed e-mail to GMAIL servers I called it a day and moved on [1]
[1] https://thomasvilhena.com/2020/01/mail-submission-under-the-...
...there's no guarantee anyone else will. Currently I am getting moaned at because the "Money Stuff" newsletter is not arriving - which appears to be because Bloomberg have flubbed their DKIM. What am I supposed to do about that, eh?
Can you maybe share what problems OP might have? I have toyed with an idea of starting something similar and would love to know what I'm getting into.
1. Getting to send email, at all: lots of hosting providers blacklist outgoing port 25 TCP specifically to prevent random people getting their IPs put on a spam blacklist
2. Getting your IPs de-blacklisted: unless you get really lucky whatever IP you _start_ with has a good chance of already being on several blacklists, and some make it stupidly hard to get your IP off the list even if the ban was from 5 years ago by whoever had the IP back then
3. To even have a chance of your emails being deliverable you have to understand and configure reverse DNS, SPF, DKIM, DMARC (and probably a few other I've forgotten or which have been invented since I tried this)
4. Even after you get this far, major providers like gmail are likely to send your email straight to /dev/null because you're a new provider with no reputation
5. If (or more accurately when) somebody manages to abuse your service to send a ton of spam you'll get re-blacklisted and have to fix that all over again and implement/fix spam filters to stop people like this (this will probably happen several times as you constantly attempt to battle spammers)
6. You're going to want some sort of incoming spam filter, because people don't really like spam in their inbox, and most existing open source and/or free solutions are mediocre at best
7. If you use a weird TLD (i.e. not .com/.org/.net/similar) random online business will not allow your email or not send to you properly, and your customers will blame you despite you being able to do almost nothing about it
8. Even if you use a "standard" TLD to get past 7 some particularly bad actors will use a email domain _whitelist_, so only gmail and friends are allowed, and again your users will blame you
It was a bit of a pain to set up, but nothing too difficult. The worst part was setting up DKIM and SPF.
The thing is, I constantly hear people saying that managing an email server is something extremely difficult and that requires constant attention.
Am I doing something foolish by attempting to do this by myself? Should I just pay for a big email provider? (They’re quite expensive for the resources my organization has)
I’ve tried to set everything up as securely as possible, but I’m not an expert in email either. I’m just afraid I might be creating big trouble for myself in the future.
Setup for a normal mailserver requires Postfix (SMTP send/recieve), Dovecot (IMAP mailbox management), SpamAssassin, a webmail frontend (Roundcube), something for user management (MySQL + PHPMyAdmin for me) and a generous amount of glue. Things like DNS records, config files, spam rules and classifiers, etc).
Blacklists are far more annoying, especially w.r.t. GMail. I use a DigitalOcean node, and some of their IP ranges are blacklisted due to past spamminess. Depending on the provider, there may or may not be a bounce email, and may or may not be a whitelisting process. I've even seen mixed results within GMail. I can send from my custom domain to my GMail without trouble, but emails to a friend using a custom domain on GMail are dropped silently. (That's the worst of self-hosting, I think. Silently dropped messages are way harder to detect than a mailer-daemon block notification.)
Long story short, it's a mess :)
On the flipside, similar commercial plans (3 domains, 20GB shared storage) run $30/mo or so, which is way more than I'm willing to spend on a vanity email. Sounds like a similar story for mailing lists.
I'd give self-hosting a shot and see how it goes. Since mailing lists are opt-in, users will know if they aren't receiving what they signed up for, and are likely to reach out for support help. That's different than conventional email, where a silent drop and no reply are hard to tell apart for the recipient.
Hope that wasn't too much info/text, and good luck!