If you're talking about the basic Application Programming Interface, then I would say anything that implements the API using chaining or the [1] Fluent Interfac

If you're talking about the basic Application Programming Interface, then I would say anything that implements the API using chaining or the [1] Fluent Interface. Examples include: LINQ, MongoDB and DOM access in HTML and JS. createOrder() .addItem('Apple') .addItem('Orange') .addItems('Tomatoe', 4) .setHighPriority() .sendEmail() To me it's a beautiful way to compose complex intention from a chaining a bunch of simple commands... like unix pipes... this should be the goal of all API's... [1] https://martinfowler.com/bliki/FluentInterface.html https://martinfowler.com/bliki/FluentInterface.html