> There is tension between the benefit of designing user-friendly APIs and the temptation to overspend on effort to design great APIs. It is sometimes hard to

> There is tension between the benefit of designing user-friendly APIs and the temptation to overspend on effort to design great APIs. It is sometimes hard to anticipate how often an API will be used. I think in antirez's case there is little 'underestimation' :) Returning to the more general practice - I agree, it's easy to spend several days building a nice abstraction for something that is not extended again, or something that is extended in a way different from what was anticipated and the abstraction doesn't help. From my experience what has worked the best in terms of internal structure, is to write a basic and working version (this is when you don't know that there are any other users) and to refactor it into a nice abstraction when you reach the point that it needs to be extended - also a huge positive is once it needs to be extended, you know what the abstraction is going to be used for.