GraphQL is a static-strong-typed application data query language and runtime designed and used at Facebook to request and deliver data to mobile and web apps since 2012, and was redesigned prior to being open sourced in 2015. GraphQL delivers nearly all data for Facebook's primary iOS and Android apps, replacing our use of REST endpoints.

This talk will briefly introduce GraphQL, the motivations for starting the project, and its impact on server and client code architecture at Facebook. Then, we will dive deeper into the design process of creating a new query language, from GraphQL experimental beginnings to lessons learned from years of use in production and then acting on those lessons for a full redesign before the recent open sourcing.