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+<!--
+SPDX-License-Identifier: MPL-2.0
+SPDX-FileCopyrightText: 2026 Jonathan D.A. Jewell (hyperpolymath)
+-->
+
+# Changelog
+
+All notable changes to `nickel-augmentation` 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(crg): add crg-grade and crg-badge justfile recipes
+- feat: nickel-augmentation 1.0.0 — proven bridge, K9 signatures, 48 tests
+- feat: proven bridge — Nickel contracts backed by Idris2 formal proofs
+- feat: 7 new reporter rules, K9 runner, 29 integration tests
+- feat: add stapeln.toml container definition
+- feat: deploy UX Manifesto infrastructure
+- feat: add CLADE.a2ml — clade taxonomy declaration
+- feat: add Nickel contract library, config-reporter CLI, and wire Justfile
+- feat: add RSR template structure and project metadata
+- feat: consolidate nickel repos into nickel-augmentation monorepo
+
+### Fixed
+
+- fix(ci): bump a2ml/k9-validate-action pins to canonical (standards#85) (#9)
+- fix(ci): sync hypatia-scan.yml to canonical (kill cd-scanner build drift) (#8)
+- fix(ci): build Hypatia escript from repo root (estate dogfood drift)
+- fix(ci): Phase-2 fleet submission must not fail the security gate (#5)
+- fix(ci): repair YAML block-scalar in workflow-linter Check Permissions step (#3)
+- fix(scorecard): enforce granular permissions and add fuzzing placeholder
+- fix(ci): Resolve workflow-linter self-matching and metadata issues
+- fix: correct email jonathan.jewell → j.d.a.jewell
+- fix: SPDX headers (AGPL→PMPL), email, author name
+
+### Changed
+
+- refactor: migrate 6SCM → 6A2 (.scm → .a2ml format)
+
+### Documentation
+
+- docs: substantive CRG C annotation (EXPLAINME.adoc)
+- docs: add TEST-NEEDS.md and/or PROOF-NEEDS.md from audit
+- docs: add EXPLAINME.adoc — prove-it file backing README claims
+
+### CI
+
+- ci: redistribute concurrency-cancel guard to read-only check workflows (#12)
+- ci: fix nonexistent actions/upload-artifact SHA pin (#7)
+- ci: bump actions/upload-artifact SHA to current v4 (#2)
+- ci: SHA-pin hyperpolymath validate-actions in dogfood-gate
+- ci: restore Dependabot security path + wire auto-merge
+
+## 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). -->