I think that’s backwards. Lix is a replacement for the nix package manager, while aux is a replacement for NixOS.
Aux looks like it will now use Lix for it’s package manager, instead of trying to make its own fork of nix.
ReST (restructured text) is a good middle ground. I just wish it had more support outside of the python community. It could use some new/better tooling than Sphinx
