DONE: exact hosted hashing gives 2.50x faster full PR589 audit

[mtpsl]

DONE — tooling contribution PR1874, commit 266d01e17f9a2537cb94590193129fc960d01dc4. Scope released.

The complete retained PR589 hosted audit is 2.50x faster locally (25.836 to 10.325 seconds); the exact instruction digest is 9.53x faster (17.417 to 1.828 seconds). All 7,843,392 instruction bytes are represented in the unchanged digest. Full output receipts are byte-identical and equal the retained receipt. All 16 inherited mutation checks pass, along with 120 byte-stream comparisons, ten changed-input controls, and malformed-index/source-pin/assertion controls. These are one-pair local measurements on Python 3.12.3/macOS arm64, not performance thresholds.

Reproduce: python3 -B research/bit-hosted-digest-fastpath/verify.py. Metadata/source-pin checks also passed. The adapter is opt-in, preserves frozen inputs and does not change kappa or claim a selected cold replay. A maintainer can consider integrating it into one active driver under that driver's existing verification obligations.

Credit clarification: the PR589 word is by DreamingOfClouds; PR555 and the P111 parameterizer are by eumemic. The hosted audit preserves the DaysSky/PR442, chafreaky/PR444 and DreamingOfClouds/PR463/PR510 lineage. Prepared by Matthieu Pascal with substantial OpenAI Codex assistance.

Original claim

CLAIM — verification engineering, OS assignment seed 91; refined card replay-runtime.

Base: 0b1cccf86e2f5132ed286a26ef0a681a495740ea.

Question: can the nine-stage PR589 hosted-owner auditor's emitted-instruction digest avoid repeated JSON serialization while retaining its exact SHA-256, event count and full hosted audit? Fixed benchmark: the retained PR589 fixture in research/community-hyperplane599-audit/pr589/bit589/v9/hosted, 7,843,392 instructions. Method: profile the frozen digest, then an opt-in source-pinned adapter that preencodes repeated JSON fragments within each invocation. No persistent cached receipt, no frozen-source edits.

Three candidates considered: isolated-test scheduling (already parallelized); locale-sensitive replay reads (covered by PR1834); hosted-instruction serialization (chosen, no direct overlap found in 527 open PRs and the latest 40 updated discussions including recent handoff claims). The full discussion-cache refresh failed; direct recent-discussion inspection succeeded. Distinct from Aaron Wang's active joint-dual containment-mask claim: different verifier, fixture and operation.

Deliverable: one small tooling package, before/after timing on the same full audit, exact receipt equality, inherited mutation suite retained, fragment equivalence and invalidation controls. Stop if the first profile or differential check refutes the proposed improvement. No new kappa, mathematical construction, selected-frontier edit, or full cold-replay claim.

Expected finish 2026-10-14 13:30 UTC; claim expires 14:30 UTC. Prepared by Matthieu Pascal (@mtpsl) with substantial OpenAI Codex assistance. Credit eumemic's PR589/PR555 chain and parameterizer, the retained PR510/PR463/PR442 hosting lineage, and the community-hyperplane599 audit archive.