We lock the answers before you play.

Registered protocols

Technical specification

Fortunautica event semantics (protocol v1)

LIFECYCLE
  ANNOUNCED -> OPEN -> LOCKED -> LIVE -> SEALED -> FINAL
  terminal alternatives: DRAW | CANCELLED | VOID
  OPEN       the event exists, the target is committed, predictions may be made
  LOCKED     predictions are closed; no further guesses are accepted
  SEALED     the session is closed and the evidence chain is computed
  FINAL      public verification succeeded; the result is authoritative
  VOID       verification failed, or a correction superseded the result
  Corrections: a FINAL event is immutable except through the published
  exceptional correction mechanism (below). Original values are never
  overwritten; each correction records prior status and prior evidence root.

TARGET DERIVATION
  A 128-byte block is drawn from the hardware QRNG and its SHA-256 is published
  as the target commitment BEFORE the first guess. The preimage is revealed
  publicly only after SEALED.
    target_commit = sha256(preimage)
    bit i         = (preimage[i // 8] >> (i % 8)) & 1     (bit 0 = LSB)

EVIDENCE CHAIN
    guess_norm = user_guess if answered, else "miss"
    leaf_hash  = sha256(f"{session_id}|{seq}|{qrng_bit}|{guess_norm}|{ts}")
    head_hash  = sha256(concatenation of leaf_hash in seq order)

PROTOCOL REGISTRY
  Each event names a protocol id. The protocol spec is published with a
  canonical SHA-256: sha256(json.dumps(spec, sort_keys=True,
  separators=(",", ":"))). Published specs are never rewritten; a change
  requires a new protocol id.

EXCEPTIONAL CORRECTIONS
  reason codes: protocol_defect | target_source_failure | evidence_mismatch |
                identity_fraud | operator_error | legal_order
  new status:   VOID | CANCELLED | DRAW
  Each correction requires a written note (>= 20 chars) and is published on the
  event page together with the prior status and prior evidence root. At most one
  correction is accepted per event; any further change requires force=true and is
  recorded as an additional, publicly visible correction.

HOW TO VERIFY WITHOUT TRUSTING US
  1. GET /api/events/{event_id}            the claim
  2. GET /api/events/{event_id}/reveal     the preimage and every trial row
  3. GET /api/integrity/protocols/{id}     the protocol spec and hash
  Then recompute, locally: sha256(preimage) == target_commit; every derived bit
  equals the recorded bit; every leaf hash and the head hash reproduce; the
  protocol spec hashes to the recorded protocol hash. A reference implementation
  is included with the service: tools/verify_event.py <base_url> <event_id>.