Are code tests actually worth it? In my eyes, all they do is separate those who have got through to the interview by blagging and/or winging it from those who genuinely know the language. They don’t really test a candidate’s coding ability, all it shows is how fast they can write a solution to a problem, however simple or complex it is.

You can see I think ‘no’ is the right answer here. Well, you’d be kind of right. I have seen so many code tests which would make even the most experienced developer cringe at first glance which are really quite simple, and others which appear to be easy but will get you escorted off the premises quicker than you can say “exponential time algorithm”.

The real question is what do you value from your development team. Do you value a quick solution to a problem you already know the answer to? Or do you value someone who can look at a problem, decompose it into its component chunks and attack it in a methodical way, whilst maybe knowing nothing about the libraries they may need to use or the techniques which are common for such a problem? I would take the second any day – development is rarely a one-size-fits-all business. Sure, you may have done task X for many clients, but I bet their infrastructure, systems and background varied enough to make the code look (and act) completely different from case to case.

Maybe I’m barking up the wrong tree here, but when you’re asking a prospective employee if they can write a quicksort algorithm in Java within 30 minutes all you are doing is replicating their university days. Quicksort implementations are ten-a-penny, and matter not in the real world (since you’d use a tried-and-tested library function anyway). In this business, it is the unknown which causes the problems, not the things which have been done by every programmer at least once in their life.

In short, code tests are a double edged sword. You’re ensuring that your interviewee actually knows what they claim to know, and that they can work under a certain amount of pressure. However, you could write off that new university graduate who lives for development just because they couldn’t implement an arbitrary algorithm within a time frame. In real life, you would give that person access to all the source material they could ever need and they would get the job done, improving their abilities. All you’re doing in the interview is testing if they remember that 9am Data Structures and Algorithms class they took in their first year at university.

After all, isn’t it all about improvement on the job?