At Compass we have seen a dramatic evolution in our API over the last 18 months. We have doubled the number of backend services we use and transitioned from a relative "mess" of different API programming patterns and technologies to a unified API architecture that is used across web and mobile. Along the way we have dramatically improved developer quality of life with improved API discoverability, consistency and maintainability.

In this talk, we will discuss our evolution - both the technology stack and the migration process to get where we are. I will present our extensible code generation framework which is at the heart of our automatically generated REST to gRPC reverse proxy and how we've been able to leverage it to empower our client and service developers. This includes generation of API documentation and client SDKs, Thrift linting, our transition to gRPC from Thrift / Finagle and even a GraphQL prototype.