Kent Beck’s 3X

Updated on July 8, 2017.

Kent Beck has been very important for me as a software developer.

I’m not sure when I first heard of him. Probably sometime in the 1990s. Perhaps around the time when I read Designing object-oriented software by Rebecca Wirfs-Brock.

The book describes the practice of discovering objects using simple index cards, called CRC cards. In discussing possible designs you recorded potential objects and their classes, the responsibilities of these classes, and their collaborators. This was an idea by Kent Beck and Ward Cunningham, who invented the Wiki.

Then around 1999 or 2000, I heard about Extreme Programming, XP.

Somewhere, Beck has described XP as an attempt to distill the software development practices of Cunningham. It’s a set of five values and a list of twelve practices that help you succeed with software projects.

The 1990s had seen several attempts at finding ways to successfully build software. These were usually called methodologies and addressed things like analysis, design, handling requirements, documenting everything that happened in projects, planning the work, and so on.

XP were a reaction to these heavyweight methodologies. And there were other examples. Some that come to mind are Feature Driven Development, Lean Software Development, and of course Scrum. These were collectively called agile methods or processes, following the release of the Agile Manifesto. But XP has had the strongest effect on me.

For about six years now, Kent Beck has been at Facebook. There, it seems to me, he has been forced to re-evaluate XP, as well as his beliefs about how software should be built. In the past few months, he has begun trying to distill what he has learned. He calls this 3X, from the three distinct phases: explore, expand, extract.

Here are the Facebook notes he has written on this topic (in chronological order):

The Product Development Triathlon

Comparing Explore, Expand, and Extract: Topics in 3X

Estimates in 3X

Sequencing in 3X

Teams in 3X

Time in 3X

Money in 3X

Economy in 3X

Lean Startup is Explore

Explore a Tree

Cost of Coupling Versus Cost of De-coupling

There are currently three talks by Beck on 3X, on YouTube and elsewhere (again, chronological order):

3X with Kent Beck

Kent Beck’s Product Development Triathlon: The Three-Phased Approach That Changed Everything

Kent Beck on 3X – Explore, Expand and Extract

Updates: On July 8, 2017, I added the link Cost of Coupling Versus Cost of De-coupling. On June 9, 2017, I added the links The Product Development Triathlon, Lean Startup is Explore, and Explore a Tree, which I somehow had missed. I also added the videos 3X with Kent Beck, and Kent Beck’s Product Development Triathlon.