rnix-parser VS nickel

I definitely plan to support as much as I can, but there is definitely a level of complexity that can never be truly translated to a graphical tool. What I've found helpful during development for me is that I split the frontend GUI and the backed parser and editor into two projects (nixos-conf-editor and nix-editor), that way I could tackle a lot of the parsing and editing alone without worrying about specific GUI features needed (and use it for other projects). Later when I need some feature I add it to nix-editor. So far nix-editor supports simple attribute modification, array adding and popping, and recursive attribute definition and dereferencing. It's definitely not perfect by any means, but so far it's been enough for the projects I've been working on. I definitely need to credit any success I've had so far to the developers of rnix-parser which translates nix expression to easy to manage ASTs.

I'm hopeful that with https://github.com/nix-community/rnix-parser being a thing now, we can get some better Nix tooling, particularly for stuff like linting and doc extraction.

Okay, yes, I agree with all of that. Flakes are kind of a module system, but having clearer semantics around functions and classes would definitely help with both code readability and producing better stack traces.

And a proper type system would be awesome.

Regarding docs, it is interesting that portions of the nixpkgs source do seem to have docblock-like comments above the functions, but AFAICT there's no formalized process for extracting or rendering those. Given that https://github.com/nix-community/rnix-parser exists, I wonder how big of a leap it would be to actually extract those, render them into rST pages, and generate a searchable Sphinx manual.

So, its key features are:

1. domain-specific: designed for conveniently creating and composing derivations. This reason alone already justifies a new language, or an embedded domain-specific language (such as the Guile/Scheme for guix), or a mix of both (Starlark, the build language of Bazel embedded in a restricted Python-variant).

2. purely functional: this ties well into the philosophical backing of Nix the package manager, which aims to be purely functional, also known as hermeticity in other build systems (Bazel).

3. lazily evaluated: similar to other build systems (including Bazel), so that you can build only what you need on demand.

4. dynamically typed: this one is controversial. Being dynamically typed—in other words, not developing a type system—gets Nix out of the door first. But users often complain about the lack of proper types and modularity. There are experiments to address this, such as Nickel (https://github.com/tweag/nickel).

It is understandable that a one-pager may not have space for the whys.

Nickel：Nickel is a straightforward configuration language aimed at automatically generating static configuration files. Essentially, it's akin to JSON with the addition of functions and types.

Also look at nickel which is an evolution of nix. It's my favorite in this space.

nickel-lang.org

https://github.com/tweag/nickel

Or this https://github.com/tweag/nickel

Nickel is a programming language. While HCL is just a configuration format, so not really comparable.

Here's a comparison with similar tools: https://github.com/tweag/nickel#comparison

As for 'providence', I suppose you meant provenance :) it's been delayed because this was less critical for 1.0 to decide on or to implement (as it: it doesn't break backward compatibility in any way to add this feature in the short term), but this is very much on the roadmap: Issue #235. That's a must-have in a language with merging like Nickel.

Have you considered using a different language for templating? this could be a BIG selling point. Some good ones are cue-lang (though I haven't seen support for rust), kcl or nickel-lang.