[Macha]

I think the problems with nix-env come down to two things:

- nix-env -i and nix-env -u will almost certainly eventually do the wrong thing for you if you use them enough (nix-env -iA is ok): https://ianthehenry.com/posts/how-to-learn-nix/ambiguous-pac...

- It's not reproducible as it depends on the state of your nix-channel setup at that time. How much of a problem this is depends on your use case. nix-as-homebrew-replacemnt or nix-as-shared-package-list-across-osx-and-linux users are probably fine with this, as what these users care about is more portability than reproducibility, but nix-as-predictable-dev-environment types will be let down by it.

I think the fact that the latter affects different users differently and that the new flake world doesn't offer a "modify your global environment without the tool taking over" option (expecting you to use nixOS or nix-darwin instead) has meant that there's not enough motivation to agree on a replacement that nix-env could tell you to use instead.

I guess the eventual replacement will be "nix profile", but while you'll find at least some documentation on "nix develop" and "nix flake", I had to look in the CLI tool docs for this one, which makes me suspect it's even less final than the other two

So instead the community will tell you to avoid nix-env, but there's no agreement to have the tool or docs tell you that.