Software Craftsman Yule Calender: 17th of December

Todays word: "Waterfall"

As stated before, it is important to not only recognize the faults of past paradigms, but also the fortés which gave rise to them in the first place.

Such a beast is waterfall. It was originally contemplated because software is difficult to change. That is its premise. Code commiting design. You need good upfront design before committing to code. And you need good requirement specs before committing to the design preceding the code.

All this changes when code no longer commits design. When software, when properly groomed, is painless to change. One of the primary motivations for waterfall does a 180 degree turn overnight.

But still, waterfall may still be suitable and sometimes even necessary.

Suitable:
* Irreduceable designs. Some designs are based on a design vision that would be hard pressed to be achieved incrementally.
* When specs will not change. When there is no reason to assume that there will be any learning curve underway from start to finish. Neither with the developer or the stakeholder. If I can get all specs up front, I will gladly receive them. I just don't think this will be true more than once or twice in a life time.

Necessary:
* Even though well crafted code now responds well to change, there are still elements to solutions which do not. Such as business contracts, hardware and third party stuff.