Architecture — Attestree Supply-Chain Platform

System Architecture

Attestree is a software supply-chain platform for Windows fleets built around a single idea: verify provenance at ingest, not after install. Most scanners inspect binaries that are already deployed across a fleet; Attestree owns the catalog and distribution layer, so policy is enforced before an artifact ever reaches an endpoint.

The system has two surfaces: a control plane + agent that runs the ingest gate, attestation, and ring-promoted deployment, and a public front door — the marketing site and an open-core community edition.

Ingest Gate

Every package pulled from a source — winget today, with additional package managers and custom MSI/MST on the roadmap — passes through a policy gate before admission.

Stage	Responsibility
Fetch	Retrieve the artifact and its metadata from the configured source
Provenance check	Verify build provenance and signatures against trusted roots
SBOM	Attach / verify a CycloneDX software bill of materials
Policy evaluation	Enforce minimum SLSA level, CVE-severity ceiling, and license allow-list
Decision	Admit (with a signed receipt) or reject — rejected artifacts never reach a ring

Ring-Promoted Deployment

Admitted artifacts roll out through promotion rings rather than fleet-wide at once, so a bad package is contained to a small blast radius and can be rolled back with a single policy change.

Source ──► Ingest Gate ──► Signed Attestation
                                  │
                                  ▼
                          Canary ──► Pilot ──► Broad ──► All
                                  │
                          auto-rollback on failure signal

Attested Inventory

Alongside the deploy path, Attestree maintains a unified, attested inventory across every package manager a device runs — a single rollup instead of reconciling per-tool outputs. A CVE matrix reconciles reported inventory against public vulnerability feeds (NVD / OSV / MSRC), and the whole picture exports as a signed bundle an auditor can verify independently.

Control Plane Stack

Layer	Choice
Server runtime	Windows Server 2025
Client / agent	Windows 11, .NET, AOT-compiled agent + installer shim
Operational store	PostgreSQL with per-tenant scope enforced as a first-class invariant
Distribution	OCI-compatible registries
Attestation	Signed receipts; managed signing keys today, Sigstore-rooted verification on the roadmap

Open-Core Distribution

Attestree ships as open-core. The SYSTEM/User installer shim and its IPC contract are open source under Apache-2.0; the platform itself is closed-source. A community edition is published as a cosign-signed Docker image for self-hosting, with the commercial control plane available as multi-tenant SaaS or a self-hosted appliance built from the same bundle.

Public Front Door

The marketing site at attestree.com is a separate, fully public surface:

Layer	Choice
Framework	Astro with Tailwind (via PostCSS) + MDX, static output
Hosting	Cloudflare Pages (Git-integration deploys, preview deploy per PR)
Waitlist	Same-origin Cloudflare Pages Function backed by D1 in an EU jurisdiction
Bot defense	Cloudflare Turnstile
Build security	SHA-pinned GitHub Actions, least-privilege `GITHUB_TOKEN`, committed lockfile, Dependabot, and an `npm audit` CI gate