Low level programming forums and communities?

How low-level do you want to go?

Jack Ganssle's The Embedded Muse is excellent if you are interested in embedded systems and microcontrollers: http://www.ganssle.com/tem-back.htm

I also like Hackaday for hardware hacks (not necessarily just low-level stuff, but you can filter based on tags): https://hackaday.com/

Alternatively, mailing lists for big open-source projects like the Linux Kernel Mailing List, PostgreSQL, or ffmpeg-devel are very low-level (operating systems, database internals, audio/video codecs, and hardware/firmware discussions), but require a lot of technical background to understand:

- https://lkml.org/

- https://wiki.postgresql.org/wiki/Mailing_Lists

- https://ffmpeg.org/contact.html#MailingLists

What exactly do you mean by "low level"?

And by "smaller community that focuses purely on what I enjoy", do you mean programming being the only topic of concern? No other tech, no business, no personal life stuff?