Comparison
BrownfieldvsGreenfield
Brownfield
the design was fine and half the work was making it coexist with what is already running.
Work constrained by an existing system that must keep working throughout. It is the normal condition of professional software, and it changes what a good design is: the winning option is often not the best end state but the one with a credible path from here. Estimating brownfield work as if it were greenfield is one of the most reliable ways to be badly wrong about a date.
Full entry →Greenfield
there was no existing system to accommodate, and the hardest part turned out to be deciding anything.
Work with no existing system, data or users to be compatible with. It is universally wanted and comes with its own difficulties: no constraints means no guidance, and every decision is open at once. It also carries a specific trap, which is that a greenfield build often has to be reconciled with the brownfield reality of the rest of the company on the day it launches.
Full entry →