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I read somewhere that to solve this #Nix error I needed to add my current user to the `nix-users` group, which I did, but then I got another error:

```
❯ nix-shell -p nodejs-20_x
error: creating directory '/nix/store': Permission denied
```

Again, I'm not running the command as root or with `sudo`, so it's unclear why Nix insists on attempting to run as another user.

`nix-shell` could also provide more useful error messages than "permission denied".

Not a great first impression.