I second Mailcow. I use it on a residential IP and have a smarthost for relaying in/out since my isp blocks port 25.

For relay, I use mxroute.com, I have a lifetime account and Mailcow has a fetchmail option.

If you are concerned about TruNAS, go look at Xigmanas. This is the original FreeNAS project before iX acquired the name.

Try 35 years

Somehow I’m a “Unix Wizard” because I know how to read log files?

Oh, and now I’m DevOps because I pythoned my way out of wet paper bag.

Take a look at openonserve

https://openobserve.ai/