CowboyRobot writes: The adoption of REST as the predominant method to build public APIs has over-shadowed any other API technology or approach in recent years. Although several alternatives (mainly SOAP) are still (very) prevalent in the enterprise, the early adopters of the API movement have taken a definitive stance against them and opted for REST as their approach and JSON as their preferred message format. But while REST is still the poster child of the API movement, there are a number of initiatives, technologies and discussions that are starting to nibble at the crust of the REST de-facto standard. These include: Asynchronous APIs, Orchestration / Experience APIs, the distinction between SDKs vs APIs, and Binary protocols. Common for these is the need for an interface definition in a protocol-specific format, which is then processed by included tools to generate code for supported languages. All have support for most popular languages today.