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@johnhenry/oat-sim — test without camera hardware

npm install @johnhenry/oat-sim

Encodes and decodes a full artifact through the same fountain-coded pipeline <optical-send>/<optical-receive> use, with no camera and no display — plus deliberate loss, duplication, reordering, and corruption injection, so you can test how your app handles a bad optical link without ever pointing a real camera at a real screen.

This is the package to reach for in CI, or anywhere you need to exercise the receiver’s error paths (oat-rejected, retries, partial-frame handling) deterministically.

@johnhenry/oat-bootstrap — a small transfer unlocks a bigger one

npm install @johnhenry/oat-bootstrap

The idea: a small, easily-transferred signed artifact bootstraps a faster follow-on channel that wouldn’t otherwise have a trust anchor. Two workflows ship:

• Verified release-manifest fetch — buildReleaseManifestArtifact/extractReleaseManifest/fetchAndVerifyManifest: a digest-checked, mirror-fallback HTTPS download, gated on signature verification before the fetch happens at all (see Security model — this function enforces its own check rather than trusting callers).
• Real WebRTC offer/answer — createOfferArtifact/createAnswerArtifact/applyAnswerArtifact: a genuine RTCPeerConnection with a live data channel, bootstrapped by exchanging the offer and answer as optical artifacts instead of a signaling server.

Not implemented: BitTorrent / content-addressed bootstrap was scoped as part of the original M5 milestone but never built. The pattern generalizes to it — the same “small signed artifact authorizes a bigger transfer” shape applies — it’s just not shipped code.

Everything together: the reference demo

examples/file-transfer in the repository (not published — it’s an app, not a library) wires sender and receiver together end to end: arbitrary file transfer with type-appropriate rendering, a declarative form UI proposal (safe-view kind 'form' — typed field descriptors, no HTML at all), live switching between Safe/Strict/Permissive/Locked-down receiver policies, a capability grant with a real effect (downloading a generated .ics file, re-checked at submit time), and the full ui.decision round trip sent back optically through a second sender/receiver pair.