We were recently trying to hire some software engineers at work. Our usual approach with candidates involved a team interview session where the current developers all asked questions. A question that one of the developers on my team always asked was along the lines of, “What are three books that you think are important for all developers?” That’s not exactly how he asks it, but in my mind, I translate this into, “What three books would you expect any professional developer to be familiar with?”
It’s an interesting question and you can learn a few things about the candidate from the answer. I’ve thought about it, and I know what my answer is. I suspect it’s not the answer that would necessarily win me the most points if I were a candidate interviewing with that team. My answer certainly reveals two strong biases I have: I believe all professional programmers should be near-expert level C programmers (at least in terms of the language itself, not necessarily from a practical perspective of being able to successfully develop or manage a huge C project). I also believe that all professional developers should be familiar with The Unix Way. Because it is mostly The Right Way. Whatever the market says (clearly I’m about to disagree with the market…), it’s hard for me to consider Windows a serious enterprise application development and hosting platform, and it deserves little more than to be considered a passing fad.
Right. Back to the three books:
The C Programming Language, by Brian W. Kernighan and Dennis M. Ritchie. Given my first bias, this is an obvious choice. There has never been, nor will there likely ever be, as definitive or widely recognized a volume on any language. Read it. Know it. Love it. Everything that programmers do has C underneath it. While hiring is way too complex and there are too many other factors involved to boil things down to a simple litmus test, if life were that simple, I’d go so far as to say I wouldn’t hire any developer who hasn’t read K&R cover-to-cover at least one.
Advanced Programming In The Unix Environment, by W. Richard Stevens. Here you see my other bias playing out. I don’t really care what platform your current job is for. If you’re not able to dabble in Unix system programming (in C, of course), I’m not convinced that you have the same fundamental developer chops as people who can. This isn’t necessarily a read cover-to-cover type book after you get far enough in to understand the general Unix Way, but if you haven’t actually implemented C code that does string manipulation, file I/O, network sockets, memory management, threads, safe concurrency with critical sections, etc., then using higher level languages and frameworks is a crutch and you are more likely to make bad decisions. If you know how to do it in C, though, you can use those higher level languages for practicality and productivity, but know what their underlying implementation likely looks like and make correct decisions accordingly. If you’re a Windows Guy… sorry, Unix system programming is just so much more kick-ass than Windows system programming. (By the way, University CS programs that don’t make their Operating Systems students write a Unix shell in C that has program execution, pipe support, stdin and stdout redirection support, and a few other features are really doing their students a disservice.)
The Art of Computer Programming, by Donald Knuth. This is on my list because it simply has to be. This is the definitive monograph on the subject. I’m the first to admit that I haven’t actually read it all. The first few parts of Volume 1 deserve an honest read-through. The rest is great to skim, pick out topics you’re interested in to read more in depth…but really just the overall exposure is what you’re after. Getting used to thinking about algorithms that way Knuth talks about them. These volumes are perhaps the least practical books in my entire technical library, but at the same time if you put some effort into reading them–or parts of them–you will come away smarter than you used to be. The information density in these books is impressive. And it turns out they do have a practical side, too… I have, on numerous occasions, wanted to do something and just picked an algorithm straight out of one of the books to implement.
It’s great if candidates–or any developer–have also read practical books related to the languages, frameworks, and trends that a company they are working for uses. In fact, reading the three books I listed does very little to prepare a developer to work in a real-world software company. However, without understanding these three books (level of understanding required is in the order that I listed them… fully understand The C Programming Language, have a good handle on Advanced Programming In The Unix Environment, and get what you can via osmosis with The Art of Computer Programming), I honestly believe developers are at a disadvantage, and it will show in their software.