nixpkgs/modules

<nixpkgs>/modules

This directory hosts subdirectories representing each module class for which the nixpkgs repository has user-importable modules.

Exceptions:

• _class = "nixos"; modules go in the <nixpkgs>/nixos/modules tree
• modules whose only purpose is to test code in this repository

The emphasis is on importable modules, i.e. ones that aren't inherent to and built into the Module System application.