Librem 5 May update:
@jmwright I really hope this turns out well, cuz the librem one thing lost a lot of respect from me
@Sylphox Yeah, it doesn't really seem like they're able to ensure the security of the software, and they did that whole rebranding of open source software thing.
Makerdon is a Mastodon instance focused on Makers, Open Source Hardware (OSHW) and STEM/STEAM. Free and Open Source Software (FOSS) is a likely topic as well. If you're interested in making things, allowing others to build on your work, and/or teaching others about making things, you might like this instance.