Comment by gpanders

This exact thing is what trips me up about using Nix and I haven't been able to figure out how to get around it. Sometimes you want a global Python library. Here's one example from my own use case: I want to use a Weechat Python script that depends on a Python library called "pync". With e.g. MacPorts I can just run

    sudo port install py-pync

and now the Weechat Python script will be able to "import pync". But this doesn't work with Nix since every package is completely isolated from each other.

I spent quite a bit of time trying to figure this out and was unsuccessful. I'd love to know what Nix's answer to use cases like this is.