Software Architect's Handbook

Greenfield systems

A greenfield software system is a completely new software application, one in which you can start with a clean slate. There are no constraints based on any prior work. A greenfield system can be designed for a well-understood domain or for a novel domain.

A well-understood domain is one that is mature, and the possibilities for innovation are very limited. Examples include Windows desktop applications, standard mobile applications, and enterprise web applications. There will be existing frameworks, tools, and sample architectures for the software that you need to build. The software architectures of existing applications can be used as a guide.

It will be more likely that you are developing software for a well-understood ...