[kwlug-disc] Help installing Nix packages the Proper Way(tm)

[Paul Nijjar]

I know everybody loves Nix and NixOS but I find it so frustrating.
The documentation is so misleading and I do not know the "right" way
to do things, and then I do things the wrong way and suffer. 

Here is what I did:

- I started with Debian Trixie
- I followed the advice here to install `nix-setup-systemd` and add
  myself to the `nix-users` group and add the unstable channel using
  `nix-channel` : https://imranmustafa.net/nix-on-debian/

- Then I looked for the version of the package I wanted to install:

https://lazamar.co.uk/nix-versions/?package=newsboat&version=2.21&fullName=newsboat-2.21&keyName=newsboat&revision=3b05df1d13c1b315cecc610a2f3180f6669442f0&channel=nixpkgs-unstable#instructions

On that page there are six different invocations for what I should do
to install the package, and apparently they are all incorrect? The
documentation I linked above says to use nix-env, but people on Reddit
say that nix-env is bad and you should use nix profile, and then other
people say that is wrong and you should use Home Manager and then
people say that is too complicated etc etc etc. 

Here is what I want:
- Let me install this package, preferably by editing a text file and
  running a command to activate the text file.
- It is fine for me to be the only one that runs this package
- I want the package installed permanently, not in a transient way
- If I am supposed to make a text file, tell me exactly what the
  filename is and where it goes[1], and tell me what should be in the
  file. If you point me to documentation that is fine, but if the
  documentation veers off into abstractoland immediately then that is
  not helpful. 
- If I need to run some other commands in order to set up the platform
  for that text file then that is okay; please tell me what commands I
  need.
- Tell me what I need to run in order to get the package installed so
  that I am doing thing the Right Way and not going to be burned. If
  any of these ways is the Right Way that is fine, but tell me
  something that will work and not get me burned. 

Can any of you Nix wizards help a stupid mortal out?

Am I the only one who finds the learning curve for this package
manager stupidly high? I would have thought that with its popularity
there would be clearer documentation. 

[1] Don't do this:
https://nix.dev/tutorials/first-steps/declarative-shell#a-basic-shell-nix-file
("create a file called `shell.nix`" . Okay. Where is this file
supposed to live? Anywhere? Some specific folder?)