DanNorth.net

At the beginning of this year I wrote a feature article for Better Software magazine, which was published as “Behavior Modification” back in March.

The article is now available on my site. It gives an overview of behaviour-driven development, from its origins as a coaching aid for TDD through to its current form as a proven, comprehensive development approach.

Behaviour-driven development started life as an NLP exercise to stem the abuse of the word “test” in “test-driven development”. Since then it has grown into a respectable and proven agile methodology (with a small “m” of course).

Dave Astels, the award-winning author, was an early adopter of BDD and has been instrumental in raising its profile. He presented it at Canada on Rails and is taking it to JAOO and SD Best Practices. He has even presented it to Google. His Ruby BDD framework, rspec, has inspired a number of similar projects.

Now, Dave is a programmer. What’s more, he is a very thoughtful programmer, which means he invests a lot of energy in making programming productive and effective – and more importantly fun – for himself and other programmers. He doesn’t get very excited about capturing requirements or the dynamic between testers and analysts, so you won’t hear him talking about the wider context of BDD, but you will hear him saying that there is one!

BDD is fundamentally about identifying behaviour. At the analysis level, the behaviour of a story is its acceptance criteria, which BDD expresses in the form of automated scenarios. You need analysts working with testers to capture the stories and identify the acceptance criteria, and then you need programmers working with testers to automate the scenarios.

So the ironic twist is that all that talk about “testing” in TDD was taking the focus off the real testing action! My efforts to put the word “test” back in its box have in fact propelled the testers into the central role on a BDD team.

So the message here is twofold. Firstly, although a lot of the existing BDD message is in the TDD space, don’t lose sight of the bigger picture or you’ll miss out on all the good stuff. And secondly don’t underestimate the value of the testers on your team: they are your direct line to delivering high value software.

So, it’s taken me two years to finally get round to writing down what behaviour-driven development is all about, but I’m pleased with the result. The article has just been published in the March edition of Better Software as “Behavior ((I didn’t quite get away with the UK spelling)) Modification”.

I started talking about BDD as an evolution of TDD at the back end of 2003, and played with the idea of a BDD framework, in the form of JBehave, during 2004. I made some noise about it at the Agile Developers’ Conference in June 2004, and then at the end of the year everything went kind of quiet. That’ll teach me to have a day job.

At the end of last year, I finally got back into BDD evangelist mode, and decided to write the story of behaviour-driven development: where it came from, what it’s about, how it has grown and where it is going. Just when I was busy working out what I wanted to say, by a curious coincidence, Brian Marick approached me to write an article about BDD and JBehave for his excellent magazine, Better Software, which I was targeting as my ideal audience anyway. Hurrah!

You know what to do – rush to the StickyMinds.com site and take out a subscription so you can read the article and tell all your friends about it.

I have to thank Brian and his excellent editorial team, as well as the ThoughtWorkers who gently (!) shepherded me through the process of writing and editing the article. In particular, Liz Keogh, Martin Fowler (yes, that one), Joe Walnes and Rebecca Parsons were extremely helpful and supportive. Thanks guys.

Charles Simonyi introduced himself at a recent workshop with the words: “I was at Xerox PARC in the 70s, Microsoft in the 80s, and working on intentional software in the 90s”. He wasn’t showing off, he was just there. He pioneered WYSIWYG, created Microsoft Word, Excel and Access (as a data visualization tool), championed OO and invented metaprogramming.

What this tells me is that when Charles Simonyi thinks he is on to something, it’s probably worth listening. (Ok, I’ll forgive him szHungarian notation.) For the last 15 years, Charles has been on to intentional programming. (more…)