Brownfield Integration

Overview

Guidance for implementing tasks that touch existing code. When a task says [EXTEND], add new code following existing patterns. When a task says [MODIFY], change specific behavior as described. In both cases, read the existing code first and respect what is already there.

The existing code is not wrong until proven otherwise. It has consumers, tests, and patterns that evolved for reasons not immediately visible.

Violating the letter of the rules is violating the spirit of the rules.

When to Use

• Tasks marked with [EXTEND] — adding new functionality to existing files
• Tasks marked with [MODIFY] — changing existing behavior in files
• Any task that references files already on disk
• When following patterns established by previous cycles

When NOT to Use