Here’s a compact, implementation‑ready blueprint to make your scanner’s results quiet, explainable, and auditable end‑to‑end.

# Phase the “proof spine”

1. **SBOM‑only → VEX‑ready → Attested**

* **SBOM (now):** Generate SPDX 3.0.1 + CycloneDX 1.6 for every image/module. Include purls, CPE (if available), license IDs, source URIs, and build metadata.
* **VEX‑ready (next):** Normalize vuln inputs (OSV, GHSA, vendor feeds) to a single internal model; keep fields needed for VEX (status, justification, impact, action, timestamp, issuer).
* **Attest (then):** Emit **in‑toto/DSSE** attestations that bind: (a) SBOM digest, (b) ruleset version, (c) data sources & hashes, (d) VEX decisions. Log statement references in **Rekor** (or your mirror) for transparency.

# Explainability path (per alert)

For every surfaced finding, materialize:

* **Origin SBOM node** → component@version (with purl/CPE)
* **Match rule** → which matcher hit (name+version, range, CPE heuristics, source trust)
* **VEX gate** → decision with justification (e.g., affected/not_affected, component_not_present, configuration_needed)
* **Reachability trace** → static (call graph path) and/or runtime (probe hits) to the vulnerable symbol(s)
* **Deterministic score** → numeric risk built from stable inputs (below)
  Expose this as a single JSON object and a short, human‑readable proof block in the UI/CLI.

# Smart‑Diff (incremental analysis)

* **Change detector:** hash symbols/packages and dependency graphs; on new scans, diff against prior state.
* **Selective re‑analysis:** only re‑parse/re‑solve changed modules, lockfiles, or call‑graph regions.
* **Memoized match & reachability:** cache vuln matches and reachability slices per (component, version, framework‑model) key.

# Scoring (quiet by design)

Use stable, auditable inputs:

* **Base:** CVSS v4.0 metrics (as provided by source), fall back to v3.1 if v4 missing.
* **Exploit maturity:** explicit flags when present (known exploited, PoC available, none).
* **Reachability boost/penalty:** function‑level confirmation > package‑level guess; runtime evidence > static‑only.
* **Compensating controls:** WAF/feature flags/sandboxing recorded as gates that reduce surfaced priority (but never erase provenance).

# Minimal data contracts (copy‑paste into your code)

**SBOM node (core):**

```json
{
  "purl": "pkg:npm/lodash@4.17.21",
  "hashes": [{"alg":"sha256","value":"..."}],
  "licenses": ["MIT"],
  "build": {"sourceUri":"git+https://...","commit":"..."},
  "attestations": [{"type":"intoto","subjectDigest":"sha256:..."}]
}
```

**Finding proof (per alert):**

```json
{
  "id": "FND-abc123",
  "component": {"purl":"pkg:maven/org.example/foo@1.2.3"},
  "vuln": {"id":"CVE-2024-XXXX","source":"OSV"},
  "matchRule": {"name":"purl-eq","details":{"range":"[1.2.0,1.2.5)"}},
  "vexGate": {"status":"affected","justification":"reachable_code_path"},
  "reachability": {
    "staticPath": ["Controller.handle","Service.parse","lib/vulnFunc"],
    "runtimeHits": [{"symbol":"lib/vulnFunc","count":37}]
  },
  "score": {"base":7.1,"exploit":"poc","reach":"function","final":8.4},
  "provenance": {
    "sbomDigest":"sha256:...",
    "ruleset":"signals-1.4.2",
    "feeds":[{"name":"OSV","etag":"..."}],
    "attRef":"rekor:sha256:..."
  }
}
```

# Services & where they live in Stella Ops

* **Sbomer**: Syft‑backed generators (SPDX/CycloneDX) + DSSE signing.
* **Feedser/Concelier**: fetch & normalize vuln feeds (OSV/GHSA/vendor), maintain trust scores; “preserve‑prune source” rule stays.
* **Scanner.WebService**: orchestrates analyzers; run lattice algorithms here (per your standing rule).
* **Vexer/Excititor**: VEX issuance + policy evaluation (lattice gates).
* **Authority**: key management, DSSE signing, Rekor client (and mirror) endpoints.
* **Signals**: event‑sourced store for proofs, reachability artifacts, and scoring outputs.

# Policies (tiny DSL sketch)

```yaml
version: 1
sources:
  - id: osv
    trust: 0.9
gates:
  - id: not-present
    when: component.present == false
    action: vex(status: not_affected, reason: component_not_present)
  - id: unreachable
    when: reachability.static == false and reachability.runtime == false
    action: vex(status: not_affected, reason: vulnerable_code_not_in_execute_path)
scoring:
  base: cvss.v4 or cvss.v3
  adjust:
    - if: exploit.maturity in ["known_exploited","poc"]
      add: 0.8
    - if: reachability.function_confirmed
      add: 1.1
    - if: gate == "not-present"
      subtract: 3.0
```

# Attestations & transparency (pragmatic path)

* **Produce** DSSE‑wrapped in‑toto statements for SBOM, ScanResult, and VEXBundle.
* **Record** statement digests in Rekor (or your **Proof‑Market** mirror) with pointers back to your artifact store.
* **Bundle** offline kits with SBOM+VEX+attestations and a mini‑Rekor log segment for air‑gapped audits.

# UX: one‑screen truth

* Table of findings with **Final Score**, a **“Why?”** button expanding the 5‑part proof chain, and **Fix** suggestions.
* Global toggles: *Show only reachable*, *Mute not‑affected*, *Show deltas* (Smart‑Diff), *Export VEX*.

# “Done next” checklist

* Wire Syft→SPDX/CycloneDX→DSSE emit → Rekor client.
* Normalize feeds to a single vuln model with trust weights.
* Implement **FindingProof** schema and persist it in Signals.
* Add **Symbolizer + per‑lang reachability** stubs (even minimal) to populate `reachability` fields.
* Ship VEX export (OpenVEX/CSAF) based on current gates.
* Add Smart‑Diff over SBOM + symbol graph hashes.
* Surface the full proof chain in UI/CLI.

If you want, I can drop in concrete .NET 10 interfaces/classes for each component and a first pass of the Rekor/DSSE helpers next.