> If you want something "installed" use home-manager.

I hear you. I understand nix-env as it exists needs to go, and I can only trust you on the support side. I did not know about home-manager.

Doing my homework, from home-manager README, I can read:

> Before attempting to use Home Manager please read the warning below.

> Unfortunately, it is quite possible to get difficult to understand errors when working with Home Manager, such as infinite loops with no clear source reference. You should therefore be comfortable using the Nix language and the various tools in the Nix ecosystem.

> Home Manager targets NixOS unstable and NixOS version 20.09 (the current stable version), it may or may not work on other Linux distributions and NixOS versions.

> Also, the home-manager tool does not explicitly support rollbacks at the moment so if your home directory gets messed up you'll have to fix it yourself.

On top of being third party (for now?), all of this really does not bode confidence in the tool and severely raises the bar for adoption when all one wants is to install tmux globally for their user (IOW a bunch of symlinks in ~/.nix-profile/bin that "just works").

But the best one is this in the manual:

> This manual will eventually describes how to install, use, and extend Home Manager.

There is no section in the manual describing the usage of the tool. The Getting Started seems to be solely about development and contributing. The terse examples in the README is what made me search for the manual, and I could only get a grasp of what they entail because I have NixOS experience. Seriously, if this is deemed "general public availability" quality, this is borderline user hostile.

So, I do note the envisioned deprecated-ness of nix-env but I will continue to use that as a first rung to help people climb the ladder when I introduce people to nix until there is a suitably accessible and reliable replacement.

Indeed I successfully used it as a beachhead for people to eventually jump ship:

"see? It's easy to install and use, you'll be quite autonomous. And if you feel it's not your thing just ignore it or rm -rf /nix"

Then I bait them with e.g shell.nix (which feels like Gemfile) or nix-shell -p --run (which feels like docker run) just enough to make it relatable while teasing their curiosity.

So instead of feeling overwhelmed by a whole new arch complete with a foreign config system and an alien language, and contractually tied by configs they feel confident, uncommitted, free, empowered, and curious, and that much more likely to transition to the next rung up.

> If you just want something for quick dev use nix-shell.

That I 100% agree with, which is why I immediately described it as well. It's the hook to the next rung.

> In some cases Home Manager cannot detect whether it will overwrite a previous manual configuration.

That, to me, is a problem. I fully acknowledge the limitations and caveats of nix-env, and duly highlight them when introducing people to nix, but this means home-manager is not the tool I need, in git parlance it's way too much "porcelain" and not enough "plumbing". It feels invasive when you're still in the process of getting acquainted.

I do not want home-manager to handle launchd, nor .gitconfig. I do not use nix-darwin or NixOS, _on purpose_, as I use nixpkgs as an additional tool, an extension of existing systems.

I am fine if nix-env has some of its features revamped, or is deprecated and replaced by a better tool but in terms of some of its existing use cases it is exactly the tool needed, i.e merely allow users or root to make a package persistent and widely available for the user or for root in their PATH, as if it were a native package, and with no other side effects.

I hope you understand these are legitimate needs.