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My First Impressions of Nix

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Re: My First Impressions of Nix

#101

Post by eulenteufel »

scandinavian wrote: post #43
hamandcheese wrote: post #41

Earlier quoted context omitted.

It seems like Nixpkgs aims to minimize the number of package versions in use at one time. Not just nix, most package managers do, it seems (i.e. you wouldn't expect to find different minor versions of Nginx in Debian, would you?) So by that same logic, there is only one version of Django 4. It is definitely possible with Nix to use the precise versions of what's in your requirements.txt, but I'm not sure if the Nixpk…

I get what you are saying, but nothing you said works in practice for python packages, so not sure that I actually learned anything. Is it fair to summize that python applications with python dependencies do not really work well as nix packages and shouldn't be used?

In this case I think it is important to distinguish nix (the package manager) and nixpkgs (the popular package repository / distribution used with nix).

Packaging python applications with nix is doable, but you have to specify the exact versions of your dependencies and for that you can't easily use nixpkgs.

Nixpkgs tries to keep a minimum number of packages (like Arch or Debian as well), so each of the dependencies will typically only occur with one minor version for each release of nixpkgs.

We could still use the nixpkgs to build our application but we have to override each of our dependencies to the right version, but that approach can get quiet tedious for a large number of dependencies.

Fortunately there are tools to automatically generate your dependencies from a requirements.txt such as mach-nix or pip2nix.

Re: My First Impressions of Nix

#102

Post by rgoulter »

chisquared wrote: post #97
henrydark wrote: post #40

Earlier quoted context omitted.

I agree with everything but the last statement. This all comes down to: do you consider memoization to be state. I predict people's answers to this question will come from experience with memoization. Here's mine: I kept trying to get nix to build tensorflow locally, so that I would get the avx512 benefits of the big, but gpu-less machine I had. I hadn't realized some other derivation had already downloaded tensorflo…

Huh, is this what Nix users mean by “impure”? If so, then it makes so much more sense to me now.

Yes, but 'pure' might mean different things at different levels.

In a programming language, 'pure' would just refer to "function where you get the same output from the same input; no side effects".

In parent's case, there was an 'impurity' such that the package is meaningfully different depending on the machine it was built on.

Re: My First Impressions of Nix

#103

Post by rgoulter »

crubier wrote: post #69
hamandcheese wrote: post #8

> Nix, on the other hand, does have a concept of state. If you make a one-line change to a 200-line Nix configuration, it doesn’t have to re-do all the work from the other 199 lines. It can evaluate the state of the system against the configuration file and recognize that it just has to apply the one-line change. And that change usually happens in a few seconds. The author seems to have some misguided ideas about Nix…

Memoization is state. As a functional programming maximalist myself, I know it hurts a little bit, but still, Caching/Memoization is statefulness. That said, you are right that as a user of the system, that statefulness is abstracted from you and you don't have to worry about it (until some subtle caching bugs forces you to dive deep in the rabbit hole)

Reminds me of this more abstract perspective: you can draw an analogy between working the filesystem, and programming languages working with memory.

https://www.tweag.io/blog/2022-07-14-taming-unix-with-nix/

Re: My First Impressions of Nix

#104

Post by Filligree »

goodpoint wrote: post #93
the_gipsy wrote: post #78

Earlier quoted context omitted.

You can package simple python projects, but as soon as there are too many huge deoendecies that use CPython and whatnot, it becomes impossible to generate the nix derivation. I just use imperative python-venv + pip install on those.

Wasn't Nix supposed to solve these problems?

And it does, for most languages. Python seems more difficult than average.

Re: My First Impressions of Nix

#105

Post by thumbuddy »

madjam002 wrote: post #35
CapsAdmin wrote: post #26

I feel a little lost on nixos. Been using it for a while now on my main personal desktop and it's fine, but whenever I want to do something like running a python project (ml based ones for example), or compile software from source, I'm lost because I don't know what I'm doing. Most projects target Ubuntu, so I feel you need to know a lot about how nix really works to get them compiling, which is often not what I'm in…

I've used Nix for 5 years now and use it heavily in production, and in my opinion, just do what works for you. If you try and use Nix 100% "correctly" then you'll end up like the countless other people who tried Nix and failed. Especially for toying around in dev environments, be pragmatic and take advantage of its amazing strengths, but if distrobox lets you enjoy using NixOS and speed up your workflow, so be it. He…

Or you could... You know... Not use Nix?

Re: My First Impressions of Nix

#106

Post by teekert »

adamgordonbell wrote: post #92
hamandcheese wrote: post #8

> Nix, on the other hand, does have a concept of state. If you make a one-line change to a 200-line Nix configuration, it doesn’t have to re-do all the work from the other 199 lines. It can evaluate the state of the system against the configuration file and recognize that it just has to apply the one-line change. And that change usually happens in a few seconds. The author seems to have some misguided ideas about Nix…

Explaining what Nix is seems like one of its biggest barriers to adoption. Part of the difficulty is it means different things to different people. My colleague spent a whole lot of time trying to answer this question and ended up with this: My main take away after spending some time learning about Nix is that it embraces the functional programming concept of a pure function. If I give a function a certain set of inp…

I often find difficult to explain ideas the most interesting ones. It’s a new paradigm, naturally we need to develop “the neurons” to deal with it, to reason with it, to hold the paradigm in our minds.

I find the best way to get the paradigm is to dive in.

I see from people that did that they are always enthusiastic, it must be worth it.

Re: My First Impressions of Nix

#107

Post by thumbuddy »

adamgordonbell wrote: post #92
hamandcheese wrote: post #8

> Nix, on the other hand, does have a concept of state. If you make a one-line change to a 200-line Nix configuration, it doesn’t have to re-do all the work from the other 199 lines. It can evaluate the state of the system against the configuration file and recognize that it just has to apply the one-line change. And that change usually happens in a few seconds. The author seems to have some misguided ideas about Nix…

Explaining what Nix is seems like one of its biggest barriers to adoption. Part of the difficulty is it means different things to different people. My colleague spent a whole lot of time trying to answer this question and ended up with this: My main take away after spending some time learning about Nix is that it embraces the functional programming concept of a pure function. If I give a function a certain set of inp…

The biggest barrier to adoption unfortunately is not people's inability to explain what the tool is in my opinion. It's that the tool is incredibly complicated, extremely hard to walk someone through compared to alternative projects, and honestly... In my opinion the problem it attempts to solve doesn't really exist.

I'll take an "impure" os or package manager over a pure one any day if complexity is a thousand fold less and the learning curve doesn't require half a decade. Got stuff to do!

Re: My First Impressions of Nix

#108

Post by the_gipsy »

Filligree wrote: post #104
goodpoint wrote: post #93

Earlier quoted context omitted.

Wasn't Nix supposed to solve these problems?

And it does, for most languages. Python seems more difficult than average.

Yea python is the exception. Go, rust, nodejs, have been easy to get running with specific versions and dev envs .

Re: My First Impressions of Nix

#109

Post by [deleted] »

hamandcheese wrote: post #8

> Nix, on the other hand, does have a concept of state. If you make a one-line change to a 200-line Nix configuration, it doesn’t have to re-do all the work from the other 199 lines. It can evaluate the state of the system against the configuration file and recognize that it just has to apply the one-line change. And that change usually happens in a few seconds. The author seems to have some misguided ideas about Nix…

[deleted]

Re: My First Impressions of Nix

#110

Post by hardware2win »

maleldil wrote: post #100
hardware2win wrote: post #98

Earlier quoted context omitted.

I mean how Nix uses FP?

Did you read the entire comment? The core idea of functional programming is pure functions (given the same outputs, the output is always the same). Nix applies that to building systems.

Pure functions are just a concept that is used in FP world

Yet, pure functions can "stand alone". You do not need FP to use pure functions. They are independent from FP. You can be OOP maniac and still use them.

So unless you want to sound fancy and trendy then why call Nix functional instead of side-effects free?

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