{
  "title": "Establish a verified browser-capable OMEMO2 backend for the Web client endpoint",
  "reason": "S00-004 cannot establish the browser/worker/WASM and legacy/OMEMO2 wire-format capabilities its acceptance requires. The only maintained, audited session library on the reachable registry (@signalapp/libsignal-client@0.105.0, AGPL-3.0-only) is a Node native addon with zero .wasm assets, so it cannot run in the Web client endpoint; no maintained OMEMO2/omemo-wasm/@signalapp/libsignal package exists on the registry.",
  "reproduction": "cd experiments/0003-crypto-library && node session-probe/smoke.mjs (SMOKE_PASS, 0) shows session/ratchet+persistence work; node session-probe/wasm-unsupported.mjs (exit 2) shows wasmFiles:0, prebuilds are native *.node only; npm view omemo2-js => 404. Details: state/evidence/S00-004-auto-crypto-8bf3dcf711b9.md",
  "role": "crypto",
  "reviewer_role": "security",
  "scope": [
    "experiments/0003-crypto-library/**",
    "docs/decisions/0003-crypto-library.md"
  ],
  "outcome": "One independently reviewed probe and ADR establish a real browser/worker/WASM-capable OMEMO2 backend (library with a genuine web/WASM build and an OMEMO2 wire mapping, or traceable upstream primary-source proof covering encodings ENC-009/ENC-011), while retaining the verified audited session/ratchet engine and persistence from the existing spike.",
  "steps": [
    "Read S00-004 blocker evidence and accepted ENC-003/ENC-009/ENC-011 requirements and ADRs 0000-0002.",
    "Identify a maintained browser/worker/WASM-capable OMEMO/OMEMO2 encryption library with a real .wasm or web build and an OMEMO2 wire-format mapping; verify its license, primary-source docs, and web build.",
    "Run a focused known-answer OMEMO2 probe in the browser-compatible target inside experiments/0003-crypto-library/**; record actual results and any unsupported format as a blocker, not success.",
    "Write/update docs/decisions/0003-crypto-library.md (proposed) recording the real capability and limitations; submit evidence and handoff for independent security review."
  ],
  "acceptance": [
    "A browser/worker/WASM-capable OMEMO2 backend executes a known-answer encryption/decryption roundtrip with an authentic web build recorded in evidence.",
    "The OMEMO2 wire-format mapping is established from real primary sources and does not bypass ENC-009/ENC-011 client-endpoint encryption.",
    "No homegrown ratchet, stack/spec change without ADR, secrets in evidence, or out-of-scope edits."
  ],
  "checks": [
    "Known-answer OMEMO2 roundtrip in the web/WASM target.",
    "Web/WASM asset presence verified (non-zero real footprint), license and support checked.",
    "Independent security review confirms no bypass and no unsupported format counted as success."
  ],
  "depends_on": [],
  "requires_user_input": false
}