Hacker News new | past | comments | ask | show | jobs | submit login

I loved the idea (git everything!) until I read this:

"How do I remove a package and all of its dependencies? [...] The package manager does not do recursive dependency removal on removal of a package. This error-prone automation will not be added to the package manager. "




I made my own 'autoremove' in about 15 minutes for kiss. Its up in my repo https://github.com/jedahan/kiss-repo , and relies on having a package with all your system targets (in my case, named after my hostname) as dependencies:

    while kiss orphans | grep -qv $HOSTNAME; do
        kiss remove `kiss orphans | grep -v $HOSTNAME | tr '\n' ' '`
    done
This was much easier to implement in kiss than other package manager extensions in previous distros I've maintained packges for (gentoo, exherbo, arch, debian).


  sudo pacman -Rns $(pacman -Qqdtt)
Done.


Yuck. The only way out of dependency hell is to disallow it by allowing multiple versions/different configurations of side-by-side packages and GCing non-leaf packages. This pattern of "only one global package for everything" is failure. Too often, naïve designers will just cut things because they just don't understand them or copy & paste because they don't understand what failures exist and what solutions do/alternatives could exist.

Habitat (hab), nix, and others IIRC do SxS package mgmt.

Everything Should Be Made as Simple as Possible, But Not Simpler - possibly paraphrasing Einstein


> The only way out of dependency hell is to disallow it by allowing multiple versions/different configurations of side-by-side packages (...)

Another elegant way, for a more civilized time, is to simply disallow dependencies. If none of your packages has any dependencies, then no dependency hell is ever possible. This is possible and easy with static executables (for binary packages), and by embedding the interpreter of packages written in scripting languages.


Static binaries still have dependencies, they just embed them all into one file. That's not generically possible - as the most trivial example, consider a bash script which runs other executables. If you're trying to solve this problem, you need to actually solve it for all real cases; otherwise your solution breaks down and you're back where you started, in dependency hell.


This: perl ..


App::FatPacker will turn your (pure perl) script and its dependencies into a single file for deployment.

App::staticperl will build a static binary with the perl+C dependencies built in.

A lot of the time, it's better to use a plenv + Carton, mind, but if you want a single file for deployment, that's a solved problem in perl land too and has been for years.


This might seem like a limitation. But you can provide a base system with a toolchain & xorg with known dependencies and a limited set of packages (like a BSD base system). Then for every big and complex app clone that base system and build the app in a chroot/sandbox or container. That way you get the app and dont pollute the base system and uninstalling is just rm -rf

On every distro uninstalling packages never really reverts the system to its previous state, always leaves some junk behind.


>On every distro uninstalling packages never really reverts the system to its previous state, always leaves some junk behind.

That's not true at all. See Nix package manager (and NixOS the distro).


By and large yes. However, even on NixOS there can be various leftovers in the form of state files in /var and configuration files in /etc (outside the majority, which are managed through Nix). Unless you nuke most of the root filesystem on every boot [1].

[1] https://grahamc.com/blog/erase-your-darlings


nix is more like installing every package in its own chroot, with a few optimizations. not your starnard linux package manager


That's too much of a simplification. In NixOS you still have global configuration files, such as /etc/fstab. However, they are symlinks to Nix store paths that are associated with the current generation.

    $ realpath /etc/fstab
    /nix/store/06k708q78zxw8922rrrc8mmp5gbin4am-etc-fstab
However, NixOS installations can also end up accumulating configuration and state files that stick around when they are not defined declaratively. E.g. if you enable ssh, host keys are generated in /etc/ssh. Even if you disable ssh, these files will stick around.

You can avoid such accidental state [1], since NixOS will happily boot from a filesystem with just /boot and /nix and reconstruct the rest upon system activation. But it is quite a bit of work, since you need to manually specify what state you want to preserve (e.g. SSH host key files). Also, it currently does not work nicely with some systemd units that barf out if you make /var/run entries symlinks.

[1] https://grahamc.com/blog/erase-your-darlings


I’m just getting started with Nix, with the explicit goal of making my entire system defined in a private , remote git repo. I want to be able to rapidly re-provision my entire user environment on a new machine, including applications, preferences, etc.

For the moment I’m doing this on MacOS with the nix package manager. I’ll eventually move to NixOS. I tried to run NixOS in VirtualBox, but couldn’t get screen resizing to work despite using the official ISO which is supposed to have the appropriate extensions installed.

My current hurdle is exactly the topic of this thread: non-binary configs. For example, what am I supposed to do with .zprofile? I think I’m supposed to write a custom Nix derivation for ZSH that includes any and all customizations. I’m concerned that might cause problems with MacOS system ZSH. I can probably fix that with a custom login shell?

Anyway it’s fun, but complicated and diversely documented. Gonna take a while to sort it all out.


My current hurdle is exactly the topic of this thread: non-binary configs. For example, what am I supposed to do with .zprofile? I think I’m supposed to write a custom Nix derivation for ZSH that includes any and all customizations. I’m concerned that might cause problems with MacOS system ZSH. I can probably fix that with a custom login shell?

I use both NixOS and macOS. You can take two routes: 1. you can continue using Apple's /bin/zsh and just use a .zprofile generated using Nix (e.g. home-manager). Generally, the differences between zsh versions are not that large and it just works. This is what I have been doing with my Mac. 2. You could change your shell, either system-wide, or just for Terminal.app to ~/.nix-profile/bin/zsh.

I’ll eventually move to NixOS. I tried to run NixOS in VirtualBox, but couldn’t get screen resizing to work despite using the official ISO which is supposed to have the appropriate extensions installed.

If you have some leftover hardware, try it! NixOS is a different experience altogether and cannot be paralleled by Nix on macOS or a Linux distribution. Being able to declaratively define your whole system is insanely cool and powerful. Fully reproducible machines. Also, you can try out stuff without any harm. Just switch back to the previous working generation (or try the configuration in a VM with nixos-rebuild build-vm) if you are not happy.


> I think I’m supposed to write a custom Nix derivation for ZSH that includes any and all customizations.

Nix supports lots of approaches, with a varying degree of "buy in". I wouldn't say you're "supposed" to do one thing or another, although some things would definitely be non-Pareto-optimal (i.e. you could achieve all the same benefits with fewer downsides).

In the case of .zprofile, I would consider any of the following to be reasonable:

- A normal config file sitting on your machine, edited as needed, not version controlled.

- A symlink to a git repo of configs/dotfiles (this is what I do)

- Directly version-controlling your home dir in some way

- Writing the config content as a string in a Nix file, and having Nix put it in place upon rebuild (I do this with files in /etc)

- Having a Nix 'activation script' which copies/symlinks config files into place (this is what I do, to automate symlinking things to my dotfiles repo)

- Wrapping/overriding the package such that it always loads the desired config (e.g. by replacing the binary with a wrapper which prepends a "use this config" flag).

--

The following has nothing to do with your question, but I felt like ranting about a tangentially-related topic; it's not directed at you ;)

I often see "extremism" when Nix is brought up; e.g. if someone wants help managing non-Python dependencies of their Python app, and someone recommends trying Nix, it's often dismissed along the lines of "I don't have time to throw away my whole setup and start over with the Nix way of doing things, even if were better". The thing is, using Nix can actually be as simple as:

    (import <nixpkgs> {}).runCommand "my-app" {} ''
      Put any arbitrary bash commands here
    ''
I often treat Nix like "Make, but with snapshots". Nix 2.0 turned on 'sandboxing' by default, but if you turn that off you can do what you like: add '/usr/bin' to the PATH, 'wget' some arbitrary binaries into '/var', etc. You won't get the benefits of deterministic builds, rollbacks, concurrent versions, etc. but those don't matter if the prior method didn't have them either. Projects like Nixpkgs, and the experimental things people write about on their blogs, aren't the only way to do things; you don't have to throw the baby out with the bathwater.


Apt autoremove seems to do a pretty decent job.


especially when you pass --purge


> On every distro uninstalling packages never really reverts the system to its previous state, always leaves some junk behind.

Not at all. Apt has been able to remove everything for the last 20 years.


> Not at all. Apt has been able to remove everything for the last 20 years.

Not really. It can remove configuration files etc. it knows about, but it can't know about files later created by the application itself.


I'd say that's either 1) outside the scope of the package manager, or 2) mostly-solvable as long as your package manager allows you to specify "extra files created by the application that I do not install but I will want to uninstall."

That's also not what's being asked for here. The basic request is this: track which packages were manually vs automatically installed, and give the user the ability to remove automatically-installed orphans whose manually-installed reverse-dependencies are no longer installed. This is what APT does and it works fine 99% of the time.


Isn't that a feature? Should my settings be cleared if I uninstall a program and reinstall it later? Should all my libre office documents disappear when I uninstall libre office?


Isn't this basically what Docker is for?


Yes in that it's container tech, but for servers. Snap is the equivalent for desktop. Both have their merits.


Instead, the workflow is to remove the single package and then look at the output of the 'kiss-orphans' command to see what can now be removed. This command will list all packages which have no relationship with other packages, otherwise known as orphans.

This list may include Firefox and other "end" software so a brain is required when parsing the list. You'll come to learn the relationships between packages and their dependencies and this will eventually become effortless.

https://k1ss.org/faq


All of Gentoo's packages are in git and it does support recursive removal: https://github.com/gentoo/gentoo


Also Void and xbps.


FWIW I'm thinking: Step 1, Install Nix (or Guix.)


that sounds reasonable (and a unixy solution - combine good individual tools into a better whole)


Removal is something I've used checkinstall for in the past. Always worked perfectly.


Well, then again, many other package managers don't either. For instance XBPS and Pacman.

EDIT: I'm wrong, see below.


From the ArchWiki:

> To remove a package and its dependencies which are not required by any other installed package:

> # pacman -Rs package_name

> To remove a package, its dependencies and all the packages that depend on the target package:

> # pacman -Rsc package_name


Pacman can remove dependencies that are not used: https://wiki.archlinux.org/index.php/Pacman/Tips_and_tricks#...

This is explicit rather than implicit but it works even on one package.


But they do? (e.g. xbps-remove -R/--recursive <pkgname>)




Consider applying for YC's W25 batch! Applications are open till Nov 12.

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: