API Design Matters

from ACM Queue by Michi Henning  (2007-06-07).

After more than 25 years as a software engineer, I still find myself underestimating the time it will take to complete a particular programming task. Sometimes, the resulting schedule slip is caused by my own shortcomings: as I dig into a problem, I simply discover that it is a lot harder than I initially thought, so the problem takes longer to solve—such is life as a programmer. Just as often I know exactly what I want to achieve and how to achieve it, but it still takes far longer than anticipated. When that happens, it is usually because I am struggling with an API that seems to do its level best to throw rocks in my path and make my life difficult. What I find telling is that, after 25 years of progress in software engineering, this still happens. Worse, recent APIs implemented in modern programming languages make the same mistakes as their two-decade-old counterparts written in C. There seems to be something elusive about API design that, despite many years of progress, we have yet to master.