Wpa supplicant

Can be enabled on NixOS with networking.wireless.enable = true.

By default `wpa_supplicant` will read its configuration from /etc/wpa_supplicant.conf

Wpa_supplicant_gui

To be able to use wpa_gui as user put the following in your /etc/wpa_supplicant.conf:

ctrl_interface=/run/wpa_supplicant
ctrl_interface_group=wheel

Also your user must be part of the wheel group (replace USER with your username):

users.extraUsers.USER.extraGroups = [ "wheel" ];