I helped to plan and deliver a large scale react project for Purplebricks, a leading property sales company who recently launched in the US, leading a team of developers. As well as integrating with a further 10 from Purplebricks development team.
The react based application was written in TypeScript, compiled using babel through a webpack build. We wrote module based CSS, with each component having its own style. Each component could then make use of centralised scss variables/mixins available to import.