mikronova/modgunn

rollup — design

Class: design · Function axis: f0 the folds · f1 per-repo health · f2 fleet rollup. Strict: only the shape we run. The system view is in design.md.

f0 — the folds

rollup (module rollup.rs, always compiled — no feature) is pure higher-level folds over scan + advisory data, so a consumer can see modgunn at altitude. No warehouse, no network; the warehouse layer maps its FleetFindings in.

• SeverityHistogram::of(severities) (rollup.rs:34) — counts info/low/medium/high/critical + total; worst() (rollup.rs:51) is the top severity, health_score() (rollup.rs:70) a 0–1 health number.
• tally(items) (rollup.rs:83) — a generic frequency fold → Vec<(K, count)>.

Reuse: rollup.uses = [core, warehouse] — but only to map in FleetFindings; the folds themselves are pure and take plain input, so rollup works with or without the warehouse.

f1 — per-repo health

FindingRow (rollup.rs:102) is the pure input { repo, component, severity }; repo_health(findings) (rollup.rs:128) folds rows into RepoHealth (rollup.rs:112) { repo, vulnerable_components, findings, critical, high, worst, score } per repo.

f2 — fleet rollup

fleet_rollup(findings) (rollup.rs:170) produces FleetRollup (rollup.rs:159) { severity, repos, top_components, affected_repos } — the whole-fleet posture. The bridge from the warehouse layer is FindingRow::from_fleet (rollup.rs:184) and rollup_fleet_findings(&[FleetFinding]) (rollup.rs:191), which maps warehouse::FleetFindings straight into a FleetRollup.