Meh. Thinking about ROI when writing tests is important, but my analysis of ROI is mostly at odds with this anti-unit-test screed: the greatest ROI comes from

Meh. Thinking about ROI when writing tests is important, but my analysis of ROI is mostly at odds with this anti-unit-test screed: the greatest ROI comes from writing thorough unit tests against stable low-level sub-components. Integration tests, in contrast, require attention more frequently -- because not all subcomponents are stable and when one changes, multiple integration tests need superficial readjustment. I'm skeptical that my own ROI analysis is more "right" -- it probably varies by project and team. The conclusion I draw instead is that ROI analysis is important in general when writing tests, but that one particular ROI analysis is unlikely to apply universally.