# Handoff S00-004 - Browser OMEMO backend spike

Agent: `auto-crypto-fe1c81c17ded`
Role: crypto
Status on handoff: escalated (blocker)

## Result this run
Re-ran both committed probes unchanged from the S00-021 remediation and confirmed
the reproduced state. A verified audited session/ratchet engine and session-record
persistence are established (`@signalapp/libsignal-client@0.105.0`, known-answer
sealed-sender roundtrip, 631-byte session record reloaded byte-for-byte). The
browser/worker/WASM deployment and the legacy/OMEMO2 wire layer remain **not
available** from any maintained package on the reachable registry.

Per focused-check rule ("unsupported format recorded blocker, not success") and the
mandatory escalate protocol, S00-004 is escalated as blocked rather than claimed
done: the acceptance (legacy/OMEMO2 AND worker/wasm AND persistence) still lacks a
verified browser/WASM-capable OMEMO2 backend.

## Reproduction this run (all from project root)
1. `node experiments/0003-crypto-library/session-probe/smoke.mjs` -> exit 0,
   `SMOKE_PASS`, `KAS_OK bob stored session bytes: 631`.
2. `node experiments/0003-crypto-library/session-probe/wasm-unsupported.mjs`
   -> exit 2, `UNSUPPORTED_BLOCKER`, `pkgPresent: true`, `wasmFiles: 0`, prebuilds
   native `*.node` only.
3. Live public registry (`npm view <pkg> version`):
   - `@signalapp/libsignal-client` = 0.105.0 (Node native addon, AGPL-3.0-only).
   - `@signalapp/libsignal`, `@converse/omemo`, `@xmpp/omemo`, `omemo2`,
     `omemo-js`, `omemo-client`, `omemo-top`, `omemo-wasm` -> all E404.

## Outputs produced (all inside accepted scope)
- `state/issues/S00-004-auto-crypto-fe1c81c17ded.json` (one atomac remediation).
- `state/evidence/S00-004-auto-crypto-fe1c81c17ded.md` (this run's evidence).
- No source changes elsewhere; `docs/decisions/0003-crypto-library.md` and
  `experiments/0003-crypto-library/**` unchanged (edits outside this escalation are
  prohibited for this run).

## Next input for the remediation
1. Confirm `node experiments/0003-crypto-library/session-probe/smoke.mjs` (0) and
   `.../wasm-unsupported.mjs` (2) from project root.
2. Source or confirm a maintained browser/worker/WASM-capable OMEMO2 backend (real
   web/WASM build + OMEMO2/S ce-format mapping from traceable primary sources,
   license/support/browser constraints checked), or record the specific external
   product/administrative decision (library/provider/license) needed to bring such
   a backend in. Requires user/external input.
3. Run a focused known-answer OMEMO2 roundtrip in the web target and record actual
   results; unsupported format remains a blocker, not success.
4. Only then may acceptance-1 (legacy/OMEMO2 AND worker/wasm AND persistence) be
   re-evaluated; do not declare S00-004 done on the persistence+Ratchet part alone.