HoundShield

The local-only AI compliance firewall.

Scan every AI prompt for PHI, CUI, PII and secrets — on your own hardware. Nothing leaves the building.

Website · Try the scanner · Testing guide · Roadmap · Security

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Why HoundShield

Every cloud AI data-loss tool — Nightfall, Strac, Microsoft Purview — scans your prompts by first sending them to the vendor's servers. In a regulated environment that transmission is itself the disclosure you were trying to prevent: a DFARS 252.204-7012 CUI spill for a defense contractor, an undocumented PHI disclosure under the HIPAA Privacy Rule for a clinic.

You cannot scan regulated data for compliance by violating compliance.

HoundShield scans locally. In self-hosted mode there is no "us" in the data path.

Verified numbers

Not marketing figures — reproduce every one with the commands in docs/TESTING-GUIDE.md.

Claim	Measured	Reproduce with
Scan latency	p99 0.492 ms (budget 10 ms) · mean 0.105 ms over 2,000 cold scans	cd proxy && npm run bench
Detection coverage	90 patterns (53 builtin · 17 CMMC · 20 HIPAA) across 16 engines	lib/detection/engines.ts
App test suite	1,531 passing / 124 files	cd compliance-firewall-agent && ./node_modules/.bin/vitest run
Proxy test suite	61 passing	cd proxy && npx vitest run

Engine and pattern counts shown in the UI are computed from the shipped registries, so a marketing claim cannot silently drift from the code.

Deployment modes — read before claiming compliance

Mode	Runs on	CUI/PHI-safe?	Use for
A — Hosted	Vercel	❌ No — not FedRAMP-authorized	Demo, non-CUI evaluation
B — Self-hosted	Your infrastructure (Docker)	✅ Data never leaves your boundary	CUI and PHI workloads
C — Air-gapped	Your isolated network	✅	IL-5+, enterprise

Only Modes B and C are CUI-safe. The marketing and dashboard plane runs on Vercel — fine for a website, not fine for a regulated data path. The site says so too.

Regulatory status (updated 2026-07-28)

CMMC Phase 2 was suspended on 13 July 2026 by the Department of War. The 10 November 2026 third-party (C3PAO) certification gate no longer applies; Phases 3–4 are frozen pending a 60-day review.

What did not change: DFARS 252.204-7012, the 110 NIST SP 800-171 Rev 2 controls, and annual SPRS self-attestation all remain in force. With no assessor in the loop, that score is the contractor's own representation to the government — and DOJ's Civil Cyber-Fraud Initiative has settled 15 False Claims Act cases over exactly that.

Quickstart

git clone https://github.com/thecelestialmismatch/HoundShield.git
cd HoundShield

# The product — the local scanning proxy
cd proxy && npm install && npm run dev

# The web plane — marketing, checkout, evidence export
cd ../compliance-firewall-agent && npm install && npm run dev

Point your AI client's base URL at the proxy and send a prompt; anything sensitive is flagged before it leaves the machine.

Docker (Mode B): proxy/Dockerfile builds today, but houndshield/proxy:latest is not yet published. Publishing needs the DOCKERHUB_USERNAME / DOCKERHUB_TOKEN repo secrets plus a proxy-v* tag — .github/workflows/docker-publish.yml does the rest.

Repository map

compliance-firewall-agent/   Next.js 15 · React 19 — marketing, checkout, dashboard
  app/                       App Router — public pages, /console, 59 API routes
  lib/classifier/            90 detection patterns (builtin · CMMC · HIPAA)
  lib/detection/engines.ts   Single source of truth for engine + pattern counts
  lib/reports/               PDF generation + SHA-256 evidence chain
  lib/billing/               Entitlements + PURCHASABLE_OFFER (what is actually for sale)

proxy/                       Node.js HTTPS intercept — THE PRODUCT
  patterns/index.ts          33 standalone patterns (extend, never replace)
  scanner.ts                 The hot path — benchmarked on every CI run
  ooda/                      Observe/orient/decide loop + SQLite audit store

docs/                        STRIPE-FIX · TESTING-GUIDE · ROADMAP-12-MONTH ·
                             SECURITY-ROTATION · OUTREACH-HEALTHCARE

Testing

cd compliance-firewall-agent && ./node_modules/.bin/vitest run   # 1531 tests
cd proxy && npx vitest run                                       # 61 tests
cd proxy && npm run bench                                        # p99 < 10ms gate
cd compliance-firewall-agent && npm run build                    # must pass pre-deploy
curl -s https://www.houndshield.com/api/health                   # live smoke test

Two traps that cost real debugging time — both exit 0 while failing:

• Never pass --reporter=basic to vitest (fails with ERR_LOAD_URL).
• Never run npx vitest from the repo root — it loads the parent repo's config and tests nothing. Always cd into the package first.

Read the last lines of output. Never trust an exit code from a piped command.

Proxy tests failing with NODE_MODULE_VERSION is a stale native binary, not a code bug:

cd proxy && npm rebuild better-sqlite3

Pricing

One offer: a $499 one-time AI Risk Assessment Report. No subscription, no per-seat licence, no contract. $499 sits below most corporate-card and signature thresholds, so it does not need procurement approval. The in-browser scanner at /demo is free and needs no account.

Status — honest

Working: the scanner, 16 detection engines, the SHA-256 audit chain, the PDF generator, the in-browser demo, auth, both test suites, the production build.

Broken or missing:

• Checkout — /api/health reports payments: malformed_key. Fix: docs/STRIPE-FIX.md
• Distribution — houndshield/proxy:latest unpublished, so a customer cannot install Mode B
• Zero paying customers — the real gap, and not an engineering one

Contributing

Both test suites and npm run build must pass before a commit. Never push to main directly. See CONTRIBUTING.md and SECURITY.md.

License

MIT — see LICENSE.