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Comment by capableweb | Hacker News Reader

Again, misunderstandings seems to run rampant in this thread...

No, Docker doesn't maintain systems, it handles applications. No one runs systems inside of Docker. People run applications with Docker, and Docker itself runs on systems.

And no, Nix doesn't "do this differently and better", as what Docker does and Nix does is wildly different. Nix is for machines, not applications. Sure, a subset of features from Nix can be used like Docker, but that doesn't mean Nix and Docker is the same, no matter what you think of markets or whatever.

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I think what the parent is alluding to is: What is the practical point of using Nix when similar outcomes can be reached with more mainstream solutions? In other words, suppose I want to deploy a web app that depends on Nginx, PHP, and PostgreSQL.

I could:

(a) Run all as docker-compose type solution

(b) Run all as scripted Nix solution

Lets ignore "c" for the moment as the goal is to avoid that exact scenario. Given the prevalence and widespread support for "a" why should sysadmins choose "b"?

I don't understand how you can use docker-compose, docker, Kubernetes or anything else to achieve the same thing as NixOS. NixOS gives you a fully reproducible personal computing system, from boot config, window manager, partitioning to applications, home directories and everything in between.

What mainstream options are available for doing this? Guix could be one option, but it's not mainstream so I'm not sure what tools you are referring to.

And why would someone want that? Sure it sounds theoretically nice, especially if I was still working in IT. But learning another system with a poor ui has a large cost for a theoretical benefit.

Eh you can do the same thing (or close enough) with a bash install script on a "stock" linux system and then a docker set up with the applications that that you want. Or with ansible. it really depends on the end goal. Not everyone needs every single bit to be the same. Or you can just image a drive. It depends on the end goal and often multiple solutions will get you there.

moreover, you can also use docker digest instead of tags, that is: instead of docker pull postgresql:11 you can do docker pull postgresql@sha:xxxx....

These are the nasty solutions I have to deal with at work all the time and my entire job consists of handling things when the "quick" bash cloud init script that someone wrote and various people have made additions to over the years goes wrong.

Bash scripts fail at this task because they are generally not convergent. Ansible makes a basic effort at being convergent, but most of the scripts I've seen are extremely naive about the ways in which a configuration can diverge.

You are talking past the comment that you replied to, and you haven't answered it.

Guess I'm missing the whole subject of this thread then. The submission is about NixOS, which is for full systems (like in personal computers), something you cannot build with either Docker nor Kubernetes, the technologies that WastingMyTime89 said seems to compete with NixOS.

Nix is (a) and (c), depending on how you want to use it. What differentiates it from docker-compose or `dnf install` isn't just the fact that you can ship something in containers or install some packages but also the various properties those containers or packages inherit from the build system.

I guess the nix way would be more performant because it does not need layers of OSes

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