[hiljusti]

Not necessary, but certainly it's easier to implement and get stuff done. It starts to break down and show its cracks the larger and larger it gets, though.

The difference between almost all Linux or BSD packaging systems and nixpkgs is like the difference between dynamic and compile-time-type-checked programming languages.

[pxc]

You can have a much more conventional package manager without pre- or post-install hooks. One ex-Debian developer created such a package manager as a research project, presumably to prove a point to other Debian people with the same head-in-the-sand attitude about the state of Debian's package tooling.

It doesn't require the same kind of patching as Nix does (although sometimes patching does help avoid requiring those scripts).

Check it out: https://distr1.org/