The Art of Agile Development, 2nd Edition

No Bugs

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Whole Team

We release with confidence.

If you’re on a team with a bug count in the hundreds or thousands, the idea of “no bugs” probably sounds ridiculous. I’ll admit it: no bugs is an ideal to strive for, not something your team will completely achieve. There will always be some bugs. (Or defects; I use “bug” and “defect” interchangeably.)

But you can get closer to the “no bugs” ideal than you might think. Consider Nancy van Schooenderwoert’s experience with Extreme Programming. She led a team of novices working on a real-time embedded system for farm combines: a concurrent system written in C, with some assembly. If that’s not a recipe for bugs, I don’t know what is. According to her analysis of data by Capers Jones, the average team developing this software would produce 1,035 defects and deliver 207 to the customer.

Here’s what actually happened:

The GMS team delivered this product after three years of development, having encountered a total of 51 defects during that time. The open bug list never had more than two items at a time. Productivity was measured at almost three times the level for comparable embedded software teams. The first field test units were delivered after approximately six months into development. After that point, the software team supported the other engineering disciplines while continuing to do software enhancements. [VanSchooenderwoert2006]

“Embedded Agile Project by the Numbers with Newbies”

Over three years, the team generated ...