Combining TDD/BDD with DDD

Its not unnatural to think that the prototypical xDD combinations (TDD, BDD, DDD, and friends) are somehow in competition with each other. If you are unsure of their exact meanings, why wouldn’t you believe that TDD is in opposition to BDD and DDD? I mean, they all mean “Hmmhmm Driven Design/Development”. How many things can really drive design or development at the same time?

But, luckily, this turns out to be a misconception. At least in this case: Domain-driven design (DDD) can be very well applied together with Test-driven development or Behaviour-driven development. This post describes one way you might think about this. You may find a much better way for your situation.

xDD: An Overview

I don’t know if it’s more comical or tragical to see all those xDD combinations that exist in software development. By “xDD” I mean any one of TDD, BDD, DDD, RDD, FDD, etcetera. Software developers often make fun of this our tendency to suffix everything with “DD”. I have three points to make about this:

1. People get confused. They have a hard time understanding and keeping up with all the buzzwords that float around, especially if they are similar. There is some risk that they’ll simply discard all of them, even though some xDDs are truly invaluable techniques for a professional developer.
2. Even if someone thinks that one of the xDDs would be useful she may, falsely, believe that the xDDs are mutually exclusive. Some of them are, some are not, some are in-between.
3. This is a power-struggle, in some sense. The whole issue revolves around what should drive software development, i.e. what should be the most important thing. That’s a pretty big issue. What if you could go down in history as the person who understood software development so well that you found the magic key to unlock the whole field? Mind-boggling. (For the record, I don’t think there is one.)

This first post focuses on the first point; what these xDDs are. I have selected three of the most popular ones today, which I know pretty well, and tried to describe them concisely. I’ll also mention a few other xDDs as well.