Foundry is an experimental approach to custom tables in WordPress.
Many WordPress projects use custom post types because they're the most convenient way to build functionality, but this can lead to performance issues later. Foundry aims to solve this problem by providing a set of tools that make custom tables just as easy (or easier!), while allowing full control.
Foundry takes a compositional approach, allowing you to build up from the basics, incorporating the functionality you need while providing the freedom to implement anything you like on top.
Foundry is highly experimental, incomplete, and is not yet in production use. It is unlikely to be suitable for wide usage at this time, and if you use it, you should be prepared to implement things yourself.
Foundry is licensed under the GPLv2 or later.