Your team is writing an internal Java library that twenty other teams will use. How would you design its API so it can evolve without breaking clients?
~10 min by voice
How to approach it
This checks whether you understand that every public element of a library becomes a permanent contract, and whether you can build the ability to evolve into the API from day one: hide the implementation, control extension, watch binary compatibility and retire old things carefully.
The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.