Spam filtering is a horrendous problem which can never be "solved" because people continue to innovate around the filters. It only looks "solved" because gmail have enough data to do an amazing job of it.

I have a gmail account and a non-gmail account, and the non-gmail privately hosted one gets considerable spam, some of which even makes it through my manually curated filters.

I used to self-host email but the minimum time and expertise investment is now too high for me - I got fed up of having to fix breakages or losing email from random other sources.

Its a perpetual arms race, if the spammers have access to the blocking software they can work around it. Anti-evil works best when the evil cant see the inner workings.

As somebody who runs their own mail server, I think it's also just a problem of time and relative importance. The full-time job of a spammer is to spam, while I adjust my anti-spam solution only when the spam gets bad enough to prompt action in my spare time.

At this point I'd love to turn running my mail server over to a paid service that I trusted, because they could have full-time people dealing with spam proactively. But Google's free service means a lot of people no longer pay, so the market seems to be very limited.

Does no one offer a solution that uses data from "voluntarily" monitored emails which can be self-hosted?

Vipuls razor?

> Anti-evil works best when the evil cant see the inner workings.

That’s just security by obscurity.

Being able to see what a spam filter is filtering for makes it easier to avoid the rules.

It's not security through obscurity.

I suppose this is true as well. Would just be a nice to have.