Lazy loading Backbone collections with Promises
Until recently, when our customers created a campaign, they could choose to target the whole world, the U.S. or create a list of specific countries and U.S. metros (e.g. the San Francisco Bay Area, the Atlanta metro, etc.). Last week, we added the ability to target or exclude countries, metros, regions (e.g. states in the U.S., provinces in Canada,…), cities and postal codes. That meant doing a significant refactor of our geolocation code, which lead me to (finally) use Deferred objects.
