Linux required an MMU at inception[1] and currently requires an MMU. Instead you have μClinux[2] which although it is integrated with the mainline kernel since 2.x, it lacks some important features, like it has neither fork() nor autogrow stacks[3].
To expand a little bit: it provides an (almost) zero-configuration way to set up a private 'layer 2' network that you can connect your home server to, and any other machines that you want to be able to connect to it or to each other. It handles NAT traversal completely transparently.
In practice, it means that if I have a (say) NFS server connected to a Zerotier network I control, I can connect to it transparently from anywhere from another machine on that network, no matter what NATs / firewalls either machine is behind, even if they change. Perfect for phones, roving laptops, etc. I've gone to a model where I do most of my development (over mosh/tmux) on my home machine, from wherever I happen to be.
+1 for Zerotier. I really like wireguard, but Zerotier is so much easier and quicker to set up from scratch. If wireguard had ACLs and ipam built-in, it probably would probably win me over.
> ZeroTier’s software is open source and free to use for most purposes including personal use, internal use within a business or academic institution, and evaluation for uses that require commercial licensing.
I've long been confused about Wireguard getting all the attention over ZeroTier. ZT is so good at finding a communications path that I had to figure out how to block it from traversing one of my IPSec tunnels.
https://github.com/n-t-roff/sc (active fork)
https://en.wikipedia.org/wiki/Sc_(spreadsheet_calculator)
https://manpages.ubuntu.com/manpages/resolute/en/man1/sc-im....
Installable on mac and unix as ‘sc-im’