Sanity is a CMS a construction kit with a rich data model and real-time collaboration.
This repository contains the core Sanity front-end modules. It uses Lerna to manage cross-dependencies, publishing and to simplify workflows.
Unless you want to modify/contribute to the core Sanity components, you're probably better off having a look at the Sanity documentation that explains how to quickly get started using our hosted backend.
That's fantastic! Please see our Contributing guidelines