> I wonder what's the status of LaTeX 3

It's either already here or never happening, depending on your perspective [0] [1].

> it would be nice to have an automation in the style of Tectonic

What do you mean by "automation"?

[0]: https://www.texdev.net/2024/11/11/the-mythical-latex3

[1]: https://tug.org/TUGboat/tb44-1/tb136mitt-history.pdf#page=5