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+<!--
+SPDX-License-Identifier: MPL-2.0
+SPDX-FileCopyrightText: 2026 Jonathan D.A. Jewell (hyperpolymath)
+-->
+
+# Changelog
+
+All notable changes to `proof-of-work` will be documented in this file.
+
+This file is generated from conventional commits by the
+[`changelog-reusable.yml`](https://github.com/hyperpolymath/standards/blob/main/.github/workflows/changelog-reusable.yml)
+workflow (`hyperpolymath/standards#206`). Adopt the workflow in this repo's CI to keep this file in sync automatically — see
+[`templates/cliff.toml`](https://github.com/hyperpolymath/standards/blob/main/templates/cliff.toml)
+for the canonical config.
+
+The format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/);
+this project aims to follow [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+### Added
+
+- feat(abi): I5 DifficultyInRange half discharged Rust-side (#68)
+- feat(abi): discharge I3 placePreservesWF — real proof, no postulate (#128) (#60)
+- feat(abi): commit Idris2 seam + stance; discharge I5 (verified) (#56)
+- feat(crg): add crg-grade and crg-badge justfile recipes
+- feat: add stapeln.toml layer-based container definition\n\nConverted from existing Containerfile to stapeln format.\nIncludes Chainguard base, security hardening, SBOM generation.\n\nCo-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
+- feat: deploy UX Manifesto infrastructure
+- feat: add CLADE.a2ml — clade taxonomy declaration
+
+### Fixed
+
+- fix(verification): adapt to z3 0.19 API drift (#67)
+- fix(abi): unhang Foreign.idr under idris2 0.8.0 (#128) (#63)
+- fix(abi): make the proof-of-work SPARK/ABI seam actually buildable (P0) (#58)
+- fix(licence): #3 isolated — clear scaffold-placeholder leak (proof-of-work) (#57)
+- fix(ci): bump a2ml/k9-validate-action pins to canonical (#53)
+- fix(ci): sync hypatia-scan.yml to canonical (#52)
+- fix(ci): repair YAML block-scalar in workflow-linter Check Permissions step (#51)
+- fix(ci): complete Ast import removal in verification/mod.rs and cargo fmt across crate (#44)
+- fix(verify): drop unused Ast import to unbreak Rust CI
+- fix(bench): replace fraudulent black_box(42) benchmarks with real game logic
+
+### Changed
+
+- refactor: migrate 6SCM → 6A2 (.scm → .a2ml format)
+
+### Documentation
+
+- docs(abi): annotate Rust call sites with PROOF-OBLIGATION refs to Invariants.idr (#66)
+- docs(proof-needs): sync I3/I7 status to actual code state (#65)
+- docs(flake): annotate KEEP+DEP rationale (standards#102) (#61)
+- docs(governance): CRG v2.0 STRICT audit — C (declared) -> D (honest)
+- docs: substantive CRG C annotation (EXPLAINME.adoc)
+- docs: add EXPLAINME.adoc — prove-it file backing README claims
+- docs: update SCM files with project information
+
+### CI
+
+- ci(rust): convert rust-ci.yml to thin wrapper (standards#174) (#72)
+- ci: redistribute concurrency-cancel guard to read-only check workflows (#55)
+- ci(workflow): adopt hardened hypatia-scan from hyperpolymath/hypatia#237 (#49)
+- ci(dependabot): restore cargo PR limit so security PRs flow (#45)
+- ci: SHA-pin hyperpolymath validate-actions in dogfood-gate
+
+## Pre-history
+
+Prior commits to this file's introduction are recorded in git history but not formally classified into Keep-a-Changelog sections. To backfill, run `git cliff -o CHANGELOG.md` locally using the canonical [`cliff.toml`](https://github.com/hyperpolymath/standards/blob/main/templates/cliff.toml) — this is one-shot mechanical work.
+
+---
+
+<!-- This file was seeded by the 2026-05-26 estate tech-debt audit follow-up (Row-2 Phase 3); see [`hyperpolymath/standards/docs/audits/2026-05-26-estate-documentation-debt.md`](https://github.com/hyperpolymath/standards/blob/main/docs/audits/2026-05-26-estate-documentation-debt.md). -->