Distro agnostic packages like flatpaks and appimages have become extremely popular over the past few years, yet they seem to get a lot of dirt thrown on them because they are super bloated (since they bring all their dependencies with them).
NixPkgs are also distro agnostic, but they are about as light as regular system packages (.deb/.rpm/.PKG) all the while having an impressive 80 000 packages in their repos.
I don’t get why more people aren’t using them, sure they do need some tweaking but so do flatpaks, my main theory is that there are no graphical installer for them and the CLI installer is lacking (no progress bar, no ETA, strange syntax) I’m also scared that there is a downside to them I dont know about.
For development, yeah you’re supposed to use it like that, as opposed to installing dependencies systemwide. I don’t think you can even really do that on NixOS.
However, it has nothing to do with security though, but rather dependency isolation, so you can use one version of library X for one project and another for the other without them conflicting.
I mean, security is an unintended outcome of it. Any kind of isolation of packages provides a level of security.
Ehhhh, security by obscurity if anything. Every downloaded or built nix package is in /nix/store and readable for every user.