workplans: register follow-up implementation roadmap (WP-0009..0012)

WP-0009 git-backed DecisionLog + per-space append authority (keystone backing);
WP-0010 derived views (wikilinks, BackLinks, RecentChanges, AllPages/SiteMap);
WP-0011 incremental union + equivalence index + I-2 verification;
WP-0012 second adapter (git-IS-store) validating the contract on a new substrate.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

workplans/SHARD-WP-0009-git-decision-log.md

@@ -0,0 +1,101 @@
+---
+id: SHARD-WP-0009
+type: workplan
+title: "git-backed DecisionLog + per-space append authority"
+domain: whynot
+repo: shard-wiki
+status: active
+owner: tegwick
+topic_slug: whynot
+created: "2026-06-15"
+updated: "2026-06-15"
+depends_on:
+  - SHARD-WP-0007
+---
+
+# SHARD-WP-0009 — git-backed DecisionLog + per-space append authority
+
+## Goal
+
+Back the keystone with real storage: swap the in-memory `DecisionLog` (SHARD-WP-0007 T5) for a
+**git-addressable, append-only** log with a **per-space append authority (lease)**, exactly as
+`CoreArchitectureBlueprint` §8.1 specifies and `SHARD-WP-0006` T2 decided (resolves review
+B-1/B-3). The log API and the derived fold are unchanged; only storage + the concurrency model
+become real. This makes coordination-canonical state git-addressable (history/patch/review/
+backup — I-6) and read-your-writes correct across processes, not just in-process.
+
+**Non-goal:** distributed multi-node leasing beyond a single coordinator; per-space log
+sharding (blueprint O-12). Single append authority per space is the target.
+
+## Context
+
+- Keystone spec: `CoreArchitectureBlueprint.md` §8.1; decision `SHARD-WP-0006` T2.
+- Current impl: `src/shard_wiki/coordination/decision_log.py` (in-memory; same API to preserve).
+
+---
+
+## Git event-store backend (append = commit/object)
+
+```task
+id: SHARD-WP-0009-T1
+status: todo
+priority: high
+```
+
+A git-backed `DecisionLog` storage backend: each space is a ref/branch (or an objects stream);
+`append` writes an immutable event object and advances the ref; `events(space)` reads the
+ordered log; events serialize deterministically (stable JSON). Preserve the in-memory backend
+as the test/default double behind the same interface. Tests: append→git→read round-trips;
+ordering preserved; deterministic serialization.
+
+## Per-space append authority (lease)
+
+```task
+id: SHARD-WP-0009-T2
+status: todo
+priority: high
+```
+
+A **single append authority per space**: a lease/leader abstraction that serializes appends so
+the log is a total order (the ordering authority §8.6 relies on). Non-holders forward append
+intents to the holder; the lease is time-bounded and re-grantable (HA: a failed holder is
+replaced and resumes from the log head). Tests: concurrent append attempts serialize; lease
+hand-off resumes from head; a partitioned non-holder cannot fork the log.
+
+## Fold over the git log + read-your-writes across processes
+
+```task
+id: SHARD-WP-0009-T3
+status: todo
+priority: high
+```
+
+`fold` reads the git log into `CoordinationState` (unchanged semantics); verify **read-your-
+writes across separate processes/handles** against the same space ref. Tests: process A appends,
+process B (new handle) sees it; fold equals the in-memory fold for the same event sequence.
+
+## Migration + wiring
+
+```task
+id: SHARD-WP-0009-T4
+status: todo
+priority: medium
+```
+
+Make `InformationSpace` use the git backend (configurable; in-memory remains for tests). A
+one-time importer replays an in-memory/JSON log into git. Update SCOPE; `pytest` + pyflakes
+green; no behavioural change to overlay/union (same fold).
+
+---
+
+## Acceptance criteria
+
+- `DecisionLog` git backend passes the same tests as the in-memory one (API/fold parity).
+- Appends are totally ordered per space via a single append authority; read-your-writes holds
+  across processes; a non-holder never forks the log.
+- Coordination-canonical state is git-addressable (history/patch/review/backup).
+- `pytest` + pyflakes green; each task committed; state-hub synced.
+
+## Suggested task order
+
+T1 git store → T2 append authority → T3 cross-process fold → T4 migration + wiring.

workplans/SHARD-WP-0010-derived-views.md

@@ -0,0 +1,109 @@
+---
+id: SHARD-WP-0010
+type: workplan
+title: "derived views — wikilinks, BackLinks, RecentChanges, AllPages/SiteMap"
+domain: whynot
+repo: shard-wiki
+status: active
+owner: tegwick
+topic_slug: whynot
+created: "2026-06-15"
+updated: "2026-06-15"
+depends_on:
+  - SHARD-WP-0007
+---
+
+# SHARD-WP-0010 — Derived views
+
+## Goal
+
+Implement the **core derived views** over the union (`FederationRequirements` ADR-03): the
+wikilink/red-link model (ADR-06), **BackLinks** (the strongest core view), **RecentChanges**,
+and **AllPages / SiteMap**. All are derived-tier (recomputable; incrementally maintainable
+later by SHARD-WP-0011) and carry provenance. Presentation stays out of core (L6).
+
+**Non-goal:** full-text Search (hybrid delegate-or-derive — a later workplan); ranking; a UI.
+
+## Context
+
+- Views decision: `FederationRequirements.md` ADR-03; links: ADR-06. Blueprint §8.4.
+- Builds on the union (`src/shard_wiki/union/`) + coordination journal.
+
+---
+
+## Wikilink + red-link model
+
+```task
+id: SHARD-WP-0010-T1
+status: todo
+priority: high
+```
+
+A CommonMark **wikilink extension** parser (`[[Target]]` / `[[Target|label]]`) that extracts
+link targets from a page body and resolves each via the union (ADR-01): resolved → link;
+unresolved → **red-link** (createable, UC-23). CamelCase auto-link off by default (opt-in per
+space). The link **model + resolution is core**; rendering is L6. Tests: extraction, resolve vs
+red-link, CamelCase opt-in.
+
+## BackLinks (core)
+
+```task
+id: SHARD-WP-0010-T2
+status: todo
+priority: high
+```
+
+A derived **BackLinks** index over the union link graph: for any identity, the set of pages
+linking to it (UC-18). Built from T1 link extraction across attached shards; entries carry
+source provenance. Tests: A→B link yields B.backlinks ⊇ {A}; red-links don't create backlinks;
+chorus pages aggregate.
+
+## RecentChanges (core)
+
+```task
+id: SHARD-WP-0010-T3
+status: todo
+priority: medium
+```
+
+A **RecentChanges** view merging the coordination journal (overlay/apply/alias/fork events)
+with shard change signals (mtime/`current_rev`; `notify` later), ordered, across the union
+(UC-17). Each entry carries provenance (which shard / which decision). Tests: an edit and an
+alias both appear, newest-first; per-shard attribution present.
+
+## AllPages / SiteMap (core)
+
+```task
+id: SHARD-WP-0010-T4
+status: todo
+priority: low
+```
+
+**AllPages** (enumerate union identities, de-duplicated by equivalence/chorus) and a simple
+**SiteMap** (namespace tree from placements). Tests: union enumeration spans shards; chorus
+collapses to one entry with divergence noted; sitemap reflects paths.
+
+## Wiring + integration
+
+```task
+id: SHARD-WP-0010-T5
+status: todo
+priority: medium
+```
+
+Expose `InformationSpace.backlinks(name)`, `recent_changes()`, `all_pages()`, `site_map()`.
+Integration test over two shards. Update SCOPE; `pytest` + pyflakes green.
+
+---
+
+## Acceptance criteria
+
+- Wikilink resolution + red-link detection work via the union (ADR-01/ADR-06).
+- BackLinks, RecentChanges, AllPages, SiteMap computed over the union, provenance-carrying,
+  presentation-free (core only).
+- Views are derived/recomputable; no canonical state introduced.
+- `pytest` + pyflakes green; each task committed; state-hub synced.
+
+## Suggested task order
+
+T1 wikilinks → T2 BackLinks → T3 RecentChanges → T4 AllPages/SiteMap → T5 wiring.

workplans/SHARD-WP-0011-incremental-union.md

@@ -0,0 +1,104 @@
+---
+id: SHARD-WP-0011
+type: workplan
+title: "incremental union maintenance + equivalence index + I-2 verification"
+domain: whynot
+repo: shard-wiki
+status: active
+owner: tegwick
+topic_slug: whynot
+created: "2026-06-15"
+updated: "2026-06-15"
+depends_on:
+  - SHARD-WP-0007
+  - SHARD-WP-0010
+---
+
+# SHARD-WP-0011 — Incremental union + equivalence index
+
+## Goal
+
+Replace direct, recompute-on-read resolution with the **incremental-first** derived tier from
+`CoreArchitectureBlueprint` §8.7: change-driven delta maintenance of the union/indexes, an
+**indexed equivalence** path (blocking/LSH, not O(N²)) with correct retraction/propagation
+(review B-4), and the **I-2 verification** mechanism (digest + background consistency-checker).
+Rebuild becomes a bounded fallback, not the operational path.
+
+**Non-goal:** distributed maintenance; persisted on-disk index store (in-memory derived tier is
+fine for this slice). Per-tenant partitioning (I-13) is honoured structurally but multi-tenant
+deployment is later.
+
+## Context
+
+- Spec: blueprint §8.7 (incremental, blocking/LSH, rebuild-as-fallback), §8.4; review B-4 +
+  open items O-1/O-4.
+- Builds on union resolution (SHARD-WP-0007) and the views (SHARD-WP-0010) it accelerates.
+
+---
+
+## Equivalence index: blocking + verify
+
+```task
+id: SHARD-WP-0011-T1
+status: todo
+priority: high
+```
+
+A candidate-generation (**blocking**) layer — normalized title/path buckets + MinHash/LSH bands
+over content shingles — then **verify** (fingerprint / span-set overlap + curator bindings) to
+produce equivalence edges. Replaces pairwise O(N²). Tests: near-duplicates bucket together;
+unrelated pages don't; verified edges match a brute-force oracle on a small corpus.
+
+## Incremental maintenance (delta, not additive)
+
+```task
+id: SHARD-WP-0011-T2
+status: todo
+priority: high
+```
+
+Change-driven delta updates: a changed/added/removed page **re-buckets**, then (per B-4)
+**retracts** edges it leaves, **adds** edges it enters, and **propagates** to equivalence
+neighbours (a retraction can split a chorus set). Drives union/BackLinks/RecentChanges deltas.
+Tests: add/edit/remove keep the index equal to a from-scratch rebuild; a bucket-exit retracts a
+stale edge.
+
+## I-2 verification: digest + consistency-checker
+
+```task
+id: SHARD-WP-0011-T3
+status: todo
+priority: high
+```
+
+A per-partition **Merkle-style digest** of the derived tier, maintained alongside deltas, and a
+**background consistency-checker** that recomputes a sampled fold and compares; mismatch →
+**scoped recompute** of the affected region (self-healing). Makes `derived = f(canonical)`
+*verified*, not asserted. Tests: induced drift is detected and repaired; digest stable under
+equivalent event orders.
+
+## Wire incremental tier behind resolution + views
+
+```task
+id: SHARD-WP-0011-T4
+status: todo
+priority: medium
+```
+
+Route `UnionGraph.resolve` and the SHARD-WP-0010 views through the maintained index (rebuild =
+explicit fallback). Behaviour is unchanged from the consumer's view; only freshness/cost change.
+Update SCOPE; `pytest` + pyflakes green.
+
+---
+
+## Acceptance criteria
+
+- Equivalence is indexed (blocking/LSH + verify), not pairwise; matches a brute-force oracle.
+- Incremental maintenance (with retraction + propagation) keeps the derived tier equal to a
+  from-scratch rebuild; rebuild is a bounded fallback.
+- I-2 is verified by a digest + consistency-checker that detects and self-heals drift.
+- Consumer-visible resolution/views behaviour unchanged; `pytest` + pyflakes green; synced.
+
+## Suggested task order
+
+T1 equivalence index → T2 incremental maintenance → T3 I-2 verification → T4 wiring.

workplans/SHARD-WP-0012-git-shard-adapter.md

@@ -0,0 +1,96 @@
+---
+id: SHARD-WP-0012
+type: workplan
+title: "second adapter — git-IS-store shard (contract validation on a new substrate)"
+domain: whynot
+repo: shard-wiki
+status: active
+owner: tegwick
+topic_slug: whynot
+created: "2026-06-15"
+updated: "2026-06-15"
+depends_on:
+  - SHARD-WP-0007
+  - SHARD-WP-0008
+---
+
+# SHARD-WP-0012 — git-IS-store shard adapter
+
+## Goal
+
+Add a **second adapter on a different substrate** to validate the contract beyond the plain
+folder: a **git-IS-store** shard (`FederationArchitecture` T17 / TSD §A.3 — the home case where
+git is the store *and* the journal). It exercises git-native history (TSD §A.5 *adopt*),
+commit-as-write, `current_rev`=commit-sha drift detection, and the implication rules
+(attachment=git-IS-store ⟹ substrate=git ∧ history=git-native). Proves "writing an adapter +
+declaring a verified profile" is all it takes — no core changes.
+
+**Non-goal:** remote push/pull federation (VCS-replication+ping is a federation workplan);
+merge beyond fast-forward (apply-under-drift refuse is enough, as in SHARD-WP-0008).
+
+## Context
+
+- Contract: `TechnicalSpecificationDocument.md` §A; binding taxonomy §A.3; history §A.5.
+- Reuses the existing contract/conformance/overlay machinery unchanged.
+
+---
+
+## GitShardAdapter — read over a git working tree/repo
+
+```task
+id: SHARD-WP-0012-T1
+status: todo
+priority: high
+```
+
+A `GitShardAdapter` reading Markdown from a git repo: keys = tracked `*.md` paths; `read`
+returns a `Page` whose `source_rev` is the **commit sha** (HEAD or blob commit); profile =
+git-IS-store / substrate=git / history=git-native / addressing=path, validated against the
+implication rules. Tests: read tracked files; profile validates; conformance read path passes.
+
+## Write = commit; current_rev = sha (drift)
+
+```task
+id: SHARD-WP-0012-T2
+status: todo
+priority: high
+```
+
+`write(key, body)` stages + **commits** (author/message), returning the updated `Page` at the
+new sha; `current_rev(key)` returns the current commit sha for drift detection. Declare `WRITE`
++ `version`. Tests: write commits; conformance positive-write probe passes; `current_rev`
+changes after an external commit.
+
+## History adopt + integration with union/overlay
+
+```task
+id: SHARD-WP-0012-T3
+status: todo
+priority: medium
+```
+
+Adopt git-native history (TSD §A.5 *adopt*): expose a minimal page history (commit list for a
+path) behind a `version`-gated method. Integration: attach a `GitShardAdapter` to an
+`InformationSpace` alongside a `FolderAdapter` → resolve/chorus/edit/overlay/apply all work
+across substrates (apply-under-drift uses sha rev). Update SCOPE; `pytest` + pyflakes green.
+
+---
+
+## Acceptance criteria
+
+- `GitShardAdapter` passes the conformance suite (read + positive write) with a profile whose
+  implication rules hold (git-IS-store ⟹ git substrate + git-native history).
+- Write = commit; `current_rev` = sha drives apply-under-drift correctly.
+- The union/overlay/edit machinery works unchanged across folder + git shards (no core change —
+  capability-as-data proven on a second substrate).
+- `pytest` + pyflakes green; each task committed; state-hub synced.
+
+## Notes
+
+If `git` plumbing via subprocess proves heavy for tests, a thin in-repo git helper (or
+`tmp_path` repos created in tests) is acceptable; no new runtime dependency — use stdlib +
+`git` CLI already present.
+
+## Suggested task order
+
+T1 read adapter + profile → T2 write=commit + current_rev → T3 history adopt + integration.