One Smart Cucumber

I was messing around with some Ruby stuff tonight and was reading up on the Cucumber project. Cucumber is a behavior driven development (BDD) testing tool.

Anyone who talks to me about user stories knows I’m kind of a stickler on the value statement.  I think I’ve found a kindred soul in Aslak Hellesoy, the creator of Cucumber. The following comes from the Cucumber documentation.

You should discuss the “In order to” part of the feature and pop the why stack max 5 times (ask why recursively) until you end up with one of the following business values:

  • Protect revenue
  • Increase revenue
  • Manage cost

If you’re about to implement a feature that doesn’t support one of those values, chances are you’re about to implement a non-valuable feature. Consider tossing it altogether or pushing it down in your backlog. Focus on implementing the MMFs (Minimum Marketable Features) that will yield the most value.

Here is an example taken from an IRC chat session in #cucumber:

[5:08pm] Luis_Byclosure: I'm having problems applying the "5 Why" rule, to the feature
                         "login" (imagine an application like youtube)
[5:08pm] Luis_Byclosure: how do you explain the business value of the feature "login"?
[5:09pm] Luis_Byclosure: In order to be recognized among other people, I want to login
                         in the application (?)
[5:09pm] Luis_Byclosure: why do I want to be recognized among other people?
[5:11pm] aslakhellesoy:  Why do people have to log in?
[5:12pm] Luis_Byclosure: I dunno... why?
[5:12pm] aslakhellesoy:  I'm asking you
[5:13pm] aslakhellesoy:  Why have you decided login is needed?
[5:13pm] Luis_Byclosure: identify users
[5:14pm] aslakhellesoy:  Why do you have to identify users?
[5:14pm] Luis_Byclosure: maybe because people like to know who is
                         publishing what
[5:15pm] aslakhellesoy:  Why would anyone want to know who's publishing what?
[5:17pm] Luis_Byclosure: because if people feel that that content belongs
                         to someone, then the content is trustworthy
[5:17pm] aslakhellesoy:  Why does content have to appear trustworthy?
[5:20pm] Luis_Byclosure: Trustworthy makes people interested in the content and
                         consequently in the website
[5:20pm] Luis_Byclosure: Why do I want to get people interested in the website?
[5:20pm] aslakhellesoy:  :-) 
[5:21pm] aslakhellesoy:  Are you selling something there? Or is it just for fun?
[5:21pm] Luis_Byclosure: Because more traffic means more money in ads
[5:21pm] aslakhellesoy:  There you go!
[5:22pm] Luis_Byclosure: Why do I want to get more money in ads? Because I want to increase
                         de revenues.
[5:22pm] Luis_Byclosure: And this is the end, right?
[5:23pm] aslakhellesoy:  In order to drive more people to the website and earn more admoney,
                         authors should have to login,
                         so that the content can be displayed with the author and appear
                         more trustworthy.
[5:23pm] aslakhellesoy:  Does that make any sense?
[5:25pm] Luis_Byclosure: Yes, I think so
[5:26pm] aslakhellesoy:  It's easier when you have someone clueless (like me) to ask the
                         stupid why questions
[5:26pm] aslakhellesoy:  Now I know why you want login
[5:26pm] Luis_Byclosure: but it is difficult to find the reason for everything
[5:26pm] aslakhellesoy:  And if I was the customer I am in better shape to prioritise this
                         feature among others
[5:29pm] Luis_Byclosure: true!

I was impressed to find that section in the documentation. Not only do the docs detail basic usage but they go into the deeper discussion of how to apply agile principles using Cucumber. The balancing act of teaching principles and practices at the same time is no small feat. To find that in software documentation is pretty amazing.

P.S. One of my worst titles ever, I know. I think I was subconsciously inspired by the Hallmark Movie my wife had on a couple nights ago. I now realize I missed my calling as a greeting card writer.

  • jheil

    That is very cool…asking why, even on simple “of course we have to have it” things is key.