Lazy and pure and duck-typed and broken ass stack traces? Fuck that. Fuck that in particular.
Eelco fucked up. Badly. nixpkgs uses Haskell type signatures as comments in the core ‘lib’s, because duck-typed pure lazy functional is fucking insane.
The bad error messages, the useless stack traces, and the overall un-debuggability of Nix are not just minor issues. These are at the core of the steep learning curve of Nix. These are also the reason why with Nix you are often 'dead in the water' and don't know how to fix a problem, and end up googling for hours or asking somebody else who knows more about Nix.
And these issues cannot be fixed by having "better docs" or a better tutorial.
If somebody were to rewrite the language today then my suggestion would be to make it statically typed, like Haskell. I would probably also make it strict, with optional laziness, although that's less important imo. And providing good error messages and good debuggability should be explicit design goals.
Making it statically typed would necessitate a different overall design, since many of the dynamic tricks would not be possible any more, but I suspect that you would end up with a better overall design in the end.
Nix (the language) stomps like JSON or YAML for writing config files, it’s actually not bad at that, but it’s a disaster in its contemporary role.
https://researchr.org/publication/Dolstra2006
More recently there is an attempt to run Nickel as a successor for Nix: https://www.tweag.io/blog/2020-10-22-nickel-open-sourcing/
At my work those “O RLY” meme book covers are in vogue this week, and my last one was “Nix Haskell Overlays for Fun and Murder: Homicidal Ideation for the Working Hacker”.
It was my job to get Clash (the VHDL/Verilog synthesis tool on Haskell) building under Bazel via Tweag’s rules_haskell and playing nice with all our other Haskell shit. That’s 14 hours straight I’m never getting back.
But… because it’s Nix I never have to do that again. Even if I upgrade everything else I can keep nixpkgs at that version in my flake.lock and that will always work forever. So I’m cool with it.
good god pls share the link
This is the killer feature for me. My use-case for Nix is vastly different from yours, as I use it for centralized declarative configuration through NixOS, but I have an immense sense of satisfaction knowing that hell can freeze over but I'm still only a single command away from my exact setup running on (almost) any machine on the planet.
This might not matter much for most people, but making my machine work for me is something that took me years, and I can sleep well knowing that it's finally safe under Nix vs. multiple different configuration files for multiple different programs scattered across my filesystem.
Making NVIDIA drivers work with either Xorg on someone’s desk or CuDNN on the GPU boxes with like two friggin lines in the NixOS stuff is like, doing drugs or something in terms of sheer feeling great after years of chasing that shit all around Ubuntu’s broken-ass standard of living.