Module recent_provers 

Holder-eligibility cache: which peers recently proved storage of which key, against which commitment.

Phase 2d of the v12 storage-bound audit design (notes/security- findings-2026-05-22/proposal-gossip-audit-v12.md).

When the auditor successfully verifies a commitment-bound audit for peer P on key K (against P’s currently-credited commitment hash H), it inserts (P, H, now) into recent_provers[K]. Reward / quorum eligibility for P-as-holder-of-K then checks that this cache entry still matches P’s currently credited commitment hash; if P rotates the hash via fresh gossip, the cache entry becomes stale and credit is denied until the next successful audit against the new hash.

Invariants enforced here:

• Per-key cap: at most MAX_PROVERS_PER_KEY entries per key, LRU-evicted by proved_at. Bounds the per-key working set so a well-replicated key cannot fill memory.

• RT-only: only peers in the caller’s routing table populate entries — the caller is responsible for filtering before RecentProvers::record_proof; this module just stores what it’s told.

• Hash-bound credit: RecentProvers::is_credited_holder requires the cache entry’s commitment_hash to match the peer’s current commitment_hash. A peer who proves K under C1 then rotates to C2 loses credit until re-proving K under C2.

• TTL: entries older than PROVER_ENTRY_TTL are ignored by RecentProvers::is_credited_holder on read, and RecentProvers::sweep_expired reclaims their memory when a caller invokes it (e.g. periodically from the engine).

• PeerRemoved cleanup: the caller should call RecentProvers::forget_peer when a peer leaves the routing table to drop their entries immediately (faster than waiting for TTL).

Structs

ProverEntry

One cached prover entry: who proved the key, when, and against which commitment.

RecentProvers

Per-key cache of recent provers, capped at MAX_PROVERS_PER_KEY.

Constants

MAX_PROVERS_PER_KEY

Maximum number of cached provers per key.

PROVER_ENTRY_TTL

Maximum age of a cached prover entry before it is considered stale.