The default synaptics functionality (without this file) is limited for
clickpads: the right soft button area in the bottom right isn't active by
default, so the entire pad generates left-clicks. There is no way to
right-drag.
This file defines soft button areas and provides some matching rules.
These settings don't conflict with the synaptics options that NixOS
provides.
Using pkgs.lib on the spine of module evaluation is problematic
because the pkgs argument depends on the result of module
evaluation. To prevent an infinite recursion, pkgs and some of the
modules are evaluated twice, which is inefficient. Using ‘with lib’
prevents this problem.