Developed internally by Facebook from 2012 to solve REST's over-fetching/under-fetching problems in mobile apps, GraphQL inverts the model: the client specifies exactly which fields it needs in a single query, backed by a typed schema. Published as an open specification in September 2015 (Lee Byron, Nick Schrock, Dan Schafer), transferred to the GraphQL Foundation (Linux Foundation) in 2019, and adopted by GitHub, Twitter, Shopify, and Airbnb.