Jeff Sutherland explains the methodological ideas behind the Xtreme Manufacturing process used to design the WikiSpeed cars:

First have a look at this graphic:

“The diagram on your right shows the elements Joe combines to generate the process efficiencies XM achieves. As you can see most of the concepts like iterative development, continuous improvement and pairing are familiar to Agile developers. What Joe adds to the equation is object-oriented architecture.

Modularity allows for innovative design while building on iterative development. For example, the Team WIKISPEED car uses eight different and independent components. That allows the team to re-design the suspension system, speedometer or car body at any point and not have to tweak the chassis or dashboard to make the improved components fit. Modularity prevents engineering challenges from rippling through the entire design process. It also allows the team to swarm on the most important improvement without affecting the rest of the car.

Contract First Design: The interfaces between the different modules of the Wikispeed car are negotiated beforehand and the “contract” between how the modules interact with each other (bolt locations, data sharing, etc.) remain fixed until they need to be re-negotiated to accommodate a more significant change.

XM leverages Design Patterns in two ways: 1) by re-using mature designs with a proven track record; and 2) by reducing the number of different designs wherever possible to reduce complexity. Basically, don’t re-invent the wheel. If a particular bolt worked well fastening the suspension system, use it again and be done. And, if that bolt could also work reasonably well fastening the crush zone to the chassis, use it there as well. It is better to have some solutions a little over-designed than to maintain hundreds of subtly different and customized solutions. This reduces waste, saves time and lowers costs.”