"ConsistencyChecker: Where the Gate Becomes the Mirror"

The checker that ends every gate run with a question the code alone can’t answer: is this decision consistent with everything the organization has learned?

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Every other checker in the suite asks about the code in front of it. ConsistencyChecker asks about the code in front of it in the context of every decision that came before — and that makes it the seam where the Gate becomes the Mirror.

What it does

At the end of a gate run, it scores the current results against the Institutional Judgment System’s latest pulse — the statistical summary of the organization’s recent override and failure patterns. It asks three questions:

• Cluster match — does this failure match a known violation cluster? If the same rule has been failing and getting overridden for weeks across projects, that’s institutional drift, not a one-off.
• Anomaly pattern — does this checker’s failure rate deviate from the statistical baseline? A sudden spike might indicate a systemic issue.
• Unaddressed policy — was a policy change proposed for this pattern and never implemented? That’s institutional debt.

Each match is a ConsistencyFinding with a risk weight, and the score rolls up from 1.0 (fully consistent with institutional history) downward — with validity-aware discounting, so a finding based on 3 data points carries a quarter the weight of one based on 30+. A score of 0.85 means “mostly consistent.” A 0.4 means “this looks like drift — the pulse shows patterns you should know about.”

The bridge

So a gate run no longer just answers “does this pass?” It answers “does this pass, and is the decision to ship it consistent with what we’ve learned?” The first question is mechanical. The second is judgment — and ConsistencyChecker is where the mechanical gate reaches into the institutional memory and hands the judgment back to you, quantified.

That’s the whole thesis of the project in one checker: enforcement and memory, the gate and the mirror, in the same run. The rest of the story is in the Mirror posts.

Try it

quality-gate --check consistency

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Source: github.com/jpurnell/quality-gate-swift