You can't. But is that possible with any programming language specific package manager? How would that even work given that every flavour of OS/distro have their own way of providing gfortran?
Then orf dreamed of a day where you could "describe what system libraries I may need without having to execute setup.py and find out, and express compile time flags."
The link you pointed doesn't appear to handle what we were talking about. By specifying "gfortran", I hoped to highlight that difference.
riff, building on nix, seems an intriguing solution for this.