Data & Storage
Redis — ephemeral state
Redis is the short-term memory: challenges, tickets, and counters that live for seconds to hours, entirely in RAM. It is configured so nothing ever touches disk.
Redis is the sticky-notes drawer. Everything in it is temporary — a puzzle to solve, a one-time ticket, a tally of how busy things are. The drawer is wiped clean on every restart, and by design none of it is ever written to disk. Even the note labels are scrambled so they can’t point back to a person.
Redis runs with save "" (no RDB) and appendonly no (no AOF), so no key ever
hits disk; maxmemory-policy allkeys-lru evicts rather than persists. Every identity-scoped key is
scope:HMAC-SHA256(redis_ns_key, scope:identity) — a purpose-bound HKDF subkey, distinct from the
token MAC key (PVX-24). Aggregate pressure counters use non-identifying minute buckets.