Signer feature matrix

The five signer solutions share contracts, not source code. The authoritative table lives in nSealr/specs at vectors/features/signer-feature-matrix-v0.json. Each per-solution page on this site renders the live status table.

The implementation rule

A feature may be absent, forbidden, or hardware-blocked on a solution. When the same feature is active on more than one solution, each implementation must use the same contract_id and pass the same conformance vectors, unless an approved equivalent is documented in specs.

In other words: if Raspberry/Pi QR vault and ESP32 QR vault both advertise approval_digest_binding, they reproduce the exact same digest for the same canonical bytes — period.

Parity groups

Solutions that share a product class are tied through parity groups. The first one is the stateless QR vault:

Group	Solutions	Same-target features
`stateless_qr_vault`	`raspberry_qr_vault`, `esp32_qr_vault`	`request_validation_v0`, `nostr_event_review_universal`, `review_detail_pages`, `approval_digest_binding`, `physical_approval`, `sign_event_bip340`, `qr_static_request`, `qr_animated_request`, `qr_response`, `stateless_session_custody`, `manual_only_policy`, `device_display_review`, `response_verification`

If a future ESP32 QR variant shipped — say with a different display — it joins the same parity group and must keep the same behavior on shared features.

Statuses you’ll see

Each (solution × feature) cell has a target and a current:

required / optional / forbidden / not_applicable — target.
implemented, partial, planned, research, disabled_until_gates_pass, forbidden, not_applicable — current.

disabled_until_gates_pass is the honest status of real sign_event on prototype firmware: the contract exists, the code exists, the gates do not.

How the site stays in sync

Each signer page carries its own capability list in MDX frontmatter, mirrored from the upstream JSON. The requiredText frontmatter array drives a build-time validator that fails the build if a safety-contract phrase is missing from the rendered HTML. Drift between this site and the spec is therefore caught in CI.

Where to read it

Live per solution: any signer page + its inline feature matrix component.
Raw JSON: vectors/features/signer-feature-matrix-v0.json.
Conformance vectors: under vectors/ in the same repo.