Casein is a Rails gem that provides scaffolding generators and helper functions to quickly create a clean and minimal CRUD interface for your data.
It comes with a pre-rolled user-authentication system, supports user-based timezones, and is mobile-ready.
As Casein is completely decoupled from the front end, it can be added to new or existing Rails projects, or used as a standalone CMS to drive platforms built on other technologies.
Get started by following the instuctions on GitHub:
Casein 5.x on Github