Nix as a concept is amazing, Nix as a language sucks. Combining it with a LLM really is a cheatcode.
That being said, having worked on guix packages. Automated conversation is not so simple. The bottleneck for me is compilation time and cost. even with superdooper intelligence, you have to trial and error builds, fix mysterious test race conditions and match versions.
A powerful $5000 build server plus another several thousand per year for The electricity cost would go a long way to speeding up this process. Old second hand computers are not viable because the electricity cost for constantly building software on them is not cost effective.
It makes me kinda buthurt when some racist rich people can raise millions for some crappy arch skin distro soft fork, but serious, novel, from the ground up projects have to scratch around in the dirt for pennies. The project may not have truly demonstrated it's worth to justify replacing nix, but I feel it's unique and special enough that it is deserving of some money falling from the sky. It's 1 of only 2 of this style of functional packaging distribution.
I can confirm all of your comments, and someone will come up with something similar that's easier on the eyes.
That said, it has a problem with 'rootedness' as in 'what is the root of this attribute string'.
Firstly, 'with' keyword allows you to silently slice off the front end when the attribute string originates from a passed-in argument variable.
Secondly, when you arrive at foo in foo.bar, you have no concept of what the ancestor path looks like; someone is going to do an import of this file, likely store it in a named variable in the context it is needed, and then dispose it. Every time we need foo, it's being referenced from some ephemeral external context. So it's impossible to say or know "foo has 5 references" via static analysis unless we are just grepping it.
Thirdly, (related to above), when you declare services.tailscale.enable = true; you are relying on some ephemeral other location to find meaning in services-dot as declared in the current file. Metaphorically, we can't actually turn and face upstream looking up the call stack to easily see how we arrived (nor how many times we expect to arrive) at this site.
'Self' in the context of flakes is another great example of emphemeral-ness and non-discoverability...what is accessible under 'self'? It takes a PHD to describe it.
Allowing strings mixed in (foo.bar."baz".biz) and the expectation that you might be interpolating (foo.bar."${baz}".biz) is a whole nother ball of wax...