It links docker containers for local dev environments. You can launch a project with say a webapp, a cache like redis, and a db like mysql with the comamnd 'fig up'. The 3 docker containers in this case are linked via a fig.yml that defines the setup. It also attaches your local development code so realtime changes propgate through the cotainer (e.g live server reloads)

Getting a new dev onboarded with your whole dockerized stack involves:

- pip install fig

- cd into directory with fig.yml

-'fig up'

Really a great tool. Definitely recommend it. Good intro here: http://www.fig.sh/