Side Effects May Vary

Introducing SPF: An Assessment for Choosing Software by Fit

The recurring decision this method was built for is mundane to state and surprisingly hard to settle: given a need, what software should we adopt to meet it, and in what order relative to everything else on the roadmap? The instance that prompted it was a sequencing question โ€” whether to put declarative configuration of our database environment ahead of building pipeline orchestration. Both were defensible. What was missing wasn't an opinion; it was an honest way to score the choice, so the answer rested on something more durable than whoever argued longest. The instrument most teams reach for is an automation maturity ladder: manual at the bottom, scripted above it, declarative above that, autonomous at the top, with an implied instruction to climb. The trouble is that the ladder encodes a claim that doesn't survive scrutiny โ€” that more automation is always better. It isn't. Over-automating a problem is a real and expensive failure mode, and a ladder is structurally incapable of seeing it, because it only measures height. So the intention behind SPF was narrow and practical: a way to choose software that is matched to what a need actually requires, and that treats over-engineering as the failure it is. That intention has good precedent. The levels-of-automation literature has long framed its central question not as how high can we go but as which functions should be automated and to what extent โ€” an explicitly bidirectional question (Parasuraman, Sheridan and Wickens, 2000). SPF takes that same posture and points it at software selection.