nfr-validation

NFR validation

Measuring what was promised.

Why this exists

nfr-baseline writes down the targets. This skill finds out whether they hold.

The gap between the two is where a specific and common failure lives: everyone agrees performance matters, a target gets written, nobody measures it, and at go/no-go someone says "performance should be fine" — which is a feeling, not evidence, and it is accepted because the alternative is delaying the release to find out.

An FDE is well placed to break that pattern, precisely because you have no stake in the previous assumption. "We haven't measured it" is easier to say when you weren't the one who didn't measure it.

The other half of this skill is failure behavior. Systems are almost never tested for how they behave when a dependency is down, and that is exactly the condition under which they'll be judged.

When this applies

• Before release, against declared NFRs
• Someone claims performance is fine without a number
• A change board needs evidence, not assurance
• You need to know what happens when a dependency fails
• A change alters data volume, query shape, or call patterns

When it doesn't

• No NFRs declared — run nfr-baseline first, or you're measuring against nothing
• Genuinely trivial internal tooling
• Production is down or customers are failing now — that's incident-triage. Coming back later to measure a slow path is this skill.

Prerequisites

• .fde/03b-nfrs.md — required. The targets and the baseline.
• .fde/07-verification.md — this appends to it. If the file does not exist, create it with the standard header and say so in Confidence; do not pretend verification-plan already ran.
• Access to a realistic environment, or an honest statement that you don't have one

Procedure

1. Measure the same way the baseline was measured

If the baseline came from an APM p95 over thirty days, a local benchmark is not comparable and the comparison will mislead. Match the method, the percentile, and the conditions — or state plainly that you didn't and that the numbers aren't directly comparable.