I was actually recently discussing self-hosting email on Matrix a while ago, so I’ll just copy-paste below. Long story short, find the right existing email software you want to use, set it up correctly with a healthy IP address and domain (not blacklisted), the right DNS entries, and a PTR record, and it’ll work just fine.

Honestly, I haven’t had any issues with self-hosting email, and I’ve been doing it for the past 2 years. I think the trick is that you just need to set everything up correctly and then verify your setup with mail-tester.com to ensure all the headers, DNS entries, etc. are correct. There are some great projects that make it extremely easy to self-host, including Mailu github.com/mailu/mailu, Mailcow github.com/mailcow/mailcow-dockerized, Docker mailserver (https://github.com/docker-mailserver/docker-mailserver), Stalwart github.com/stalwartlabs/stalwart, and I’m sure more. I’m currently using Mailu, but I have been eyeing Stalwart, which has recently gotten quite popular and implements modern email protocols and does everything in Rust.

If I were you and just wanted to take a stab at self-hosting email, I would start with Stalwart and see how you like it. The only caveat is that it doesn’t yet come with a webmail client, so if you wanted one, you’d have to separately add that to your setup.

Something you would need to think about though is your IP address. It must be static, and it should be in a healthy IP address range (not on any popular blacklists). You also need to be able to set up rDNS (reverse DNS) / PTR record, so you can point your IP address back to your email domain.

I’ll say within the past few months there hasn’t been as much activity as there usually has been, so there’s not like a lot of new features coming in like there is for PieFed. Part of that is likely due to the fact that Mbin’s low on devs ATM, especially since one of the previous devs went AWOL. Still, I’ll say Mbin is already quite polished and works well, even if the dev team isn’t as active as they once were.

Luckily, I was able to mitigate it within the week it started, by setting up specific Cloudflare firewall rules. I just haven’t remembered to downgrade the server since it happened :)

The experience for setting up an Mbin server has greatly improved with the latest Docker setup rework. So now, it shouldn’t take more than a few minutes to get a simple Mbin setup running.

As for resource usage, my server (kbin.earth) doesn’t have anywhere close to the user base fedia.io does, but I’ve been able to run my server (which has ~150 active and ~600 total users) on a decently low-resource server. In the past month or so, it’s been a server with 16 vCPUs and 32 GB RAM, but previously it was running on 8 vCPUs and 16 GB RAM (had to upgrade due to DDOS).

I’ve been running my server for about 1.5 years (since December 2023), and most of the time it is a set-and-forget type of thing, of course, until you need to update things or troubleshoot some issue. But overall, it’s been working great, and when you do run into an issue, the Mbin devs are usually quick to help troubleshoot with you.

It is true that Mbin doesn’t have an “official” instance, but there are multiple servers that are run by the Mbin devs, including thebrainbin.org, gehirneimer.de, and kbin.melroy.org (and kbin.earth if you count me).

Happy cake day!

Porkbun and Cloudflare are the only one’s I use anymore. Great service and unbeatable prices for both.

If there are any specific features you feel are missing, feel free to reach out. We are always looking to improve. (I’m the developer btw.)

Even now, we have several major features queued for the next update and are in the process of a much needed ui overhaul.

Honey mustard

I literally just finished doing the same thing for my own foss app (and I also used Flutter). Right now I’m waiting for my production review. To get people added to your closed test, you have to either collect a list of email address, or create a google group they can join. If you use a google group, that will be a bit easier for testers to join since people can click the group link, and then the test link, instead of waiting for you to add their email.

If you can’t initially get all the testers you need, I would recommend making a post on the AndroidClosedTesting reddit; I found them really helpful to get the last few testers I needed.