oh yeah, Nix is powerful and also has quite a steep learning curve compared to other tools, but you can adopt gradually, some utility of Nix I can list out here:

• experimenting with packages with nix-shell when you are not sure if u want to install
• use it just like other package managers like homebrew, yay, etc with nix-env (imperative way, not really recommended by the community)
• manage the entire dev environment with home-manager and nix flake. If you use macOS or nixOS, you can even manage your OS settings (on macOS uses nix-darwin)
• manage dev dependency on project level with direnv + nix. for example, you don’t want to install python on your machine, but only want it active in the repo you’re working on, u can declare it inside the repo

here is my tutorial a while ago, I still don’t write the next part but this might be a good start for u. And here is my personal setup using nix and home-manager

not if what you want to install is already cached on the server, which is mostly the case

To add to the other comment, Nix really strives for true and actual reproducibility. Someone please correct me if I’m wrong, but my understanding is that even in builds it uses fake timestamps to ensure if a timestamp is in the resulting binary it doesn’t mess up the hash of it. They really do try to go a step beyond others in the realm of reproducibility it seems.

the problem nix trying to solve is reproducible build, which means from a single config file you can migrate to any machine and have the same environment, auto install and dot files. While other package manager install in a imperative way, which means you have to call the install command on every package you need and you have to remember it. That’s the basic difference. You can consider trying it if you see it’s worth it. It’s harder than any other package manager I know, but it solves a different problem.

A less theoretical advantage is that it can create the exact same environment on both Mac and Linux, and in neither case does it need to replace your primary package manager.

If the whole team is using nix, then the “setup” section of the readme just says “use nix-shell”[1] and that is more than enough for everyone.

[1]: I can’t remember if nix-shell is the right command, or not, but in theory nix can create an exact environment on every machine with one command.

The catch is that it’s hard, only if you want to use it at its max potential tho.

I mostly copy from other people’s config, not much learning at all. Heard that Guix is a good too if you only use linux, but it doesn’t have nonfree softwares right?