An application programming interface (API) represents a contract between the data and business logic provided by your service and the consumers who want to interact with this data. Breaking this contract will result in angry e-mails from developers and anguished users with broken apps. Designing an externally facing and hard-to-use API will result in few or no third-party developers using it. Similarly, if you do this with an internal API, then people will talk about you behind your back.
On the other hand, building a great external API and adhering to this contract will result in substantially ...
