01 security model
The floor principle.
Every response mixes a fresh 256-bit CSPRNG draw with any extra input and a timestamp through HKDF-SHA256 under a per-operation salt and a domain-separated label.
CSPRNG floor
crypto.getRandomValues — 256-bit, secret, never returned
+
your extra
optional client-supplied bytes
+
timestamp
8-byte monotonic tag
→
HKDF-SHA256
salted, domain-separated seed
output entropy ≥ CSPRNG floor · folding extra bytes into a hash cannot reduce it below the floor · deterministic sim output belongs here only as additive flavour, never as the source.
02 live
Generate, mix, verify.
Runs against this service. The ℤ₆ seed is unbiased (rejection-sampled) and valid as an X-Z6-KEM-Public key — the last button verifies it live against the post-quantum gateway.
// idle
03 api
Endpoints.
JSON, CORS-open. The CSPRNG floor is server-side; secret floor bytes are never returned.
POST /api/seed
{bytes?,extra?} → CSPRNG-floored seed (base64url)
POST /api/mix
{extra,bytes?} → fold your entropy into the floor
POST /api/z6seed
{extra?} → unbiased ℤ₆⁶⁴ key for sec6z /api/kem
GET /api/beacon?round=N
public reproducible beacon — not for keys
GET /api/health
service metadata