Lifecycles: Organizing Development Phases

Simple Lifecycles

One of the lifecycle models is the build-and-fix (see Figure 1). This is a model of an incomplete lifecycle. The build-and-fix is too simple for large-scale projects. Large-scale typically means above 100 KLOC; however, the authors recommend using this model for the projects below one KLOC. The build-and-fix model may be a possible option for a small-scale software solution. This downsized solution lacks agility. Therefore, it only applies for a very small product with clear requirements.

The other model the authors discuss here is rapid prototyping (see Figures. 4 and 5). It is also somewhat limited. The fact that it includes all the basic stages of the lifecycle does not change its limitations. These stages are the analysis and specification of requirements, preliminary and detailed design, implementation, unit testing, integration, product testing, maintenance, and retirement. The limit of rapid prototyping is lack of self-consistency. Actually, prototyping yields low quality code. It is true for both individual modules and the prototype as a whole. The prototype documentation is usually insufficient and incomplete. The resulting code differs from a software product. It only simulates the key functionality and certain aspects of the future software system of operational quality.

Figure 1.

Build-and-fix model