HydraCache 0.71.0

HydraCache 0.71.0 — memory accounting and retention evidence

0.71 closes the memory-ownership work begun in 0.70. It adds coherent production counters,
reporting-only retained-byte accounting, bounded-owner proofs, and active-expiry cleanup. The
release does not claim a numerical memory-footprint improvement, a Redis advantage, or
portable sizing from the AX42 measurements.

The accepted D4 candidate is the exact source and workflow commit
da8d6de409a657e0260e7fbfb4ab31d8d6ad5ca8. Its immutable M3, M8, M9 and M10 campaigns
completed 10, 8, 2 and 2 jobs respectively. M10 measured the B1 baseline and C candidate for
24 hours each. The campaign checker accepted the complete chain as ship-eligible. Results are
scoped to that source, workload, toolchain and admitted bare-metal host; later documentation and
release-governance commits do not turn into a newly measured runtime candidate.

The D3 decision admits W2a retained-byte accounting as foundation, and W4 active expiry as a
correctness fix. W2b, W5–W7, W8 and W9–W11 are explicitly deferred because the current owners
remain bounded and correct and no optional optimization cleared the preregistered evidence bar.
In particular, the post-idle B1 and C TTL samples have different live-key cardinalities and are
not a like-for-like RSS comparison. The release policy requires this negative result to remain
visible instead of presenting a no-win candidate as a performance win.

Publication requires all W0–W13 canaries, exact-commit fast and gated receipts, compatibility
checks, full CI, and release-evidence --release 0.71 --require-ship to pass. The 0.67.1
prerequisite is an evidence-only milestone with a pinned accepted closure receipt, not a
v0.67.1 package tag. The normal 0.70.0 tagged dependency is still checked.
The measured source must have a complete green main CI run and its tag must have one green
designated 0.71 admission. Legacy or nightly jobs triggered by the tag are diagnostic for this
release; their result cannot substitute for either of those two required proofs.

The D4 decision and claim limits,
measurement index,
memory accounting guide, and
D0-only sizing observations describe the method, evidence
and limitations. Sanitized archives live on the separate immutable
evidence/0.71/ax42/d4 Git branch; the complete raw archives and GitHub artifacts were
SHA-256-verified and retained off the rented host. Raw archives are not in the release branch
or main.

The v0.71.0 tag must point to the exact measured commit above. Release documentation and
governance changes may be merged later, but a runtime or scenario change requires a new
immutable measurement chain.