28 changed files with 87 additions and 1907 deletions
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@ -2,19 +2,6 @@

 All notable changes to this project will be documented in this file. See [standard-version](https://github.com/conventional-changelog/standard-version) for commit guidelines.

-### [8.9.0](https://github.com/soulcraftlabs/brainy/compare/v8.8.2...v8.9.0) (2026-07-19)
-
- docs: measured performance envelopes v1 (per-op p50/p95 at 1k and 10k, pure-JS floor) (5cabd78)
- fix: release drains in-flight writer-lock heartbeat — no phantom lock after unlink (70e4bc8)
- feat: flush() never compacts — history maintenance moves to close() with bounded passes (300d9f2)
-
-
-### [8.8.2](https://github.com/soulcraftlabs/brainy/compare/v8.8.1...v8.8.2) (2026-07-19)
-
- fix: one field-resolution law across aggregation hooks, source.where, removeMany, and find() spellings (945d92d)
- chore: push public docs to the soulcraft.com ingest door on release (42037d0)
-
-
 ### [8.8.1](https://github.com/soulcraftlabs/brainy/compare/v8.8.0...v8.8.1) (2026-07-18)

 - fix: O(1) adaptive retention accounting + historyStats fleet audit (6207e48)
--- a/RELEASES.md
+++ b/RELEASES.md
@ -8,79 +8,8 @@ Full auto-generated changelog: `CHANGELOG.md` · Releases: https://github.com/so
 - Debugging data, query, or storage behaviour
 - A new Brainy feature is available that you want to adopt

-## Removed APIs — 7.x → 8.x (the complete ledger)
-
-Every public API removed at the 8.0 major, with its sanctioned replacement. If your code
-still calls a left-column name on 8.x it throws (or the config key is rejected) — the
-replacement is always a one-line change. (Standing contract from 8.9.0 forward: removals
-happen only at majors, after ≥1 minor of loud runtime deprecation naming the replacement.)
-
-| Removed (7.x) | Replacement (8.x) |
-|---|---|
-| `brain.search(query, k)` | `find({ query })` — semantic; `find({ query, searchMode })` for hybrid |
-| `brain.getRelations({...})` | `related(id, opts)` for adjacency; `find({ connected: {...} })` for scoped traversal |
-| `brain.neural()` clustering | `find({ vector })` + aggregation `GROUP BY` |
-| `Db.search()` | `db.find({ vector })` |
-| Pre-8.0 storage path aliases (`directory`, `basePath`, …) | one `storage.path` key (old aliases throw) |
-| Reserved keys inside `metadata` bags (silently remapped in 7.x) | top-level params (`subtype`, `visibility`, `confidence`, `weight`, …) — reserved-in-bag throws |
-| 7.x COW branches layout (`branches/main/`) | generational MVCC (`asOf()`, `now()`, `db.persist(path)`) — on-disk migration is automatic at first 8.x open |
-
-The fork/snapshot family (`brain.snapshot()`, `createSnapshot()`, `restoreSnapshot()`)
-is sometimes cited as a 7.x removal — those methods never existed on 7.x; the 8.0 Db API
-(`asOf`/`persist`/`restore({confirm})`) is their first real implementation.
-
 ---

-## v8.9.0 — 2026-07-19 (flush is durability-only: history maintenance moves to close())
-
-The write path stops paying maintenance costs — the last structural piece of the
-flush-storm class (a production deployment measured single writes blocked 25–191s behind
-history reclaim running inline on flush under memory pressure):
-
- **`flush()` never compacts history.** It persists the current window's deltas and
-  nothing else — its cost no longer depends on history backlog or retention mode, in any
-  configuration. **`close()` is the auto-compaction site** (time-bounded per pass, ~5s;
-  an early stop is a consistent prefix and the next pass resumes).
- **`compactHistory()` gains `timeBudgetMs`** — bound your own maintenance windows; the
-  same resumable-prefix guarantee applies.
- **The documented trade**: a long-lived writer that never closes accumulates history
-  until its next explicit `compactHistory()`. Predictable writes, explicit maintenance.
-  If you run bounded retention on an always-on service, schedule a periodic
-  `compactHistory({ ...caps, timeBudgetMs })` in your maintenance window.
- **New public doc: `docs/performance-envelopes.md`** — measured per-op envelopes
-  (p50/p95 at stated scales, hardware, and backend, with the measuring script cited).
-  Refresh rule going forward: any release touching a measured path re-runs that op's
-  benchmark and updates the envelope in the same release.
- **New in this file: the Removed APIs 7.x→8.x table** (top of this document) — every
-  removal with its sanctioned replacement, one place, per the engine-currency contract.
-  Standing from here: removals only at majors, after ≥1 minor of loud runtime deprecation.
-
-## v8.8.2 — 2026-07-19 (one field-resolution law: reserved-field aggregates stop drifting)
-
-Four fixes from a consumer conformance audit, all rooted in the same disease — two field-resolution
-regimes where there must be one:
-
- **Aggregates grouped by a RESERVED field (`subtype`, `visibility`, …) now decrement on
-  delete.** The delete/update hooks fed the aggregation engine a partial entity view (type,
-  service, data, metadata only), so a reserved-field `groupBy` resolved to a nonexistent group
-  on the way DOWN — counts drifted upward forever after any delete, and updates that moved an
-  entity between reserved-field groups double-counted it. The hooks now pass the full-fidelity
-  entity view (every reserved field top-level, the same shape the add path uses). If your
-  deployment derives stats from reserved-field aggregates, re-define those aggregates once
-  after upgrading (a changed definition triggers one rescan) or run them fresh — the drifted
-  persisted counts do not self-heal retroactively.
- **Aggregation `source.where` on reserved fields now filters** instead of silently matching
-  nothing: the matcher resolves fields through the same resolver `groupBy` uses (top-level
-  standard fields + custom metadata), so `where: { subtype: 'note' }` means what it says.
- **`removeMany()` refuses empty/invalid selectors loudly.** A bare array passed positionally
-  (`removeMany([id])` instead of `removeMany({ ids: [id] })`), an empty params object, or
-  `ids: []` used to resolve successfully having deleted nothing. All three now throw.
- **`find()` accepts both where-key spellings.** Metadata is flattened at index time
-  (`metadata.entry.title` indexes as `entry.title`); a `metadata.`-prefixed where key now
-  falls back to its flattened spelling when the prefixed one isn't indexed — the
-  "unindexed field(s), returning []" confusion for storage-shaped spellings is gone. (A
-  literal nested custom key named `metadata` still wins when indexed as spelled.)
-
 ## v8.8.1 — 2026-07-18 (flush no longer walks the whole generation history + the import dedup off-switch is now honest)

 ### The flush-storm fix (production incident, reported by a long-running deployment)
--- a/docs/guides/snapshots-and-time-travel.md
+++ b/docs/guides/snapshots-and-time-travel.md
@ -344,12 +344,8 @@ For per-entity write coordination (rather than whole-store history), the
 ## Keeping history bounded

 Under Model-B every write is a generation, so history can grow quickly —
-Brainy auto-compacts at `close()` (time-bounded per pass) under the
-**`retention`** knob (configured on the constructor). Since 8.9.0, `flush()`
-never compacts: flushing is durability work and costs only what the current
-window's writes cost, regardless of history backlog. A long-lived writer that
-never closes keeps its history until its next explicit `compactHistory()` —
-schedule one in your maintenance window if you run bounded retention:
+Brainy auto-compacts on every `flush()`/`close()` under the **`retention`**
+knob (configured on the constructor):

 ```typescript
 // Zero-config: ADAPTIVE — keep as much history as free disk/RAM allows,
@ -363,13 +359,10 @@ new Brainy({ retention: 'all' })
 new Brainy({ retention: { maxGenerations: 1000, maxAge: 7 * 86_400_000, maxBytes: 512 * 1024 ** 2 } })
 ```

-Reclaim manually at any time (the same caps, plus an optional per-pass time
-budget for maintenance windows — an early stop is a consistent prefix and the
-next pass resumes):
+Reclaim manually at any time (the same caps):

 ```typescript
 await brain.compactHistory({ maxGenerations: 100, maxAge: 7 * 24 * 60 * 60 * 1000 })
-await brain.compactHistory({ maxBytes: 512 * 1024 ** 2, timeBudgetMs: 10_000 })
 ```

 Compaction never breaks a pinned read — record-sets are reclaimed only when
--- a/docs/performance-envelopes.md
+++ b/docs/performance-envelopes.md
@ -1,83 +0,0 @@
---
-title: Performance Envelopes
-slug: guides/performance-envelopes
-public: true
-category: guides
-template: guide
-order: 40
-description: Measured per-operation latency envelopes at stated scales — what to expect, on what hardware, and exactly how each number was produced.
-next:
-  - guides/find-limits
---
-
-# Performance Envelopes
-
-Every number on this page is **measured, never projected** — produced by the script
-cited at the bottom, against the built package (the artifact you install), on the stated
-hardware. Each entry says what was measured, at what scale, on which storage backend.
-When a release touches a measured path, that operation is re-measured and this page
-updates in the same release.
-
-Two scopes to keep straight:
-
- **These envelopes are the pure-JS engine** (no native accelerator registered) on
-  filesystem storage. This is the floor every deployment gets from `npm install` alone.
- **Accelerated deployments** (the optional native provider) publish their own numbers —
-  this page never claims them.
-
-## Read operations
-
-Reads are where the architecture pays off: after the write path has done its indexing
-work, queries answer from purpose-built indexes without scanning.
-
-| Operation | 1,000 entities | 10,000 entities | Notes |
-|---|---|---|---|
-| `get(id)` (warm) | p50 < 0.1ms | p50 < 0.1ms | served from cache/metadata index |
-| `find` (metadata: indexed equality + range, limit 100) | p50 1.0ms · p95 1.8ms | p50 7.0ms · p95 8.9ms | column-store bitmap paths |
-| `related(id)` (per-node adjacency) | p50 < 0.1ms · p95 0.2ms | p50 < 0.1ms | LSM adjacency index — O(degree), scale-independent |
-| `find` (semantic: embed + HNSW, 1k docs) | p50 178ms · p95 393ms | — | dominated by WASM query embedding (measured on a machine under concurrent load — treat the p95 as an upper bound); the vector search itself is single-digit ms |
-
-## Write operations
-
-Under Model-B **every write is its own durable generation** — a single-op `add` pays
-serialization, before-image staging, and fsync before it acks. That durability is priced
-into the write path visibly, by design:
-
-| Operation | 1,000 entities | 10,000 entities | Notes |
-|---|---|---|---|
-| `add` (single-op) | p50 167ms · p95 171ms | p50 165ms · p95 172ms | full durable generation per write — flat across scale |
-| `addMany` (bulk) | ~163ms/entity | ~187ms/entity | **currently per-item commits** — see the honest note below |
-| `relateMany` | ~0.8ms/edge | ~0.9ms/edge | edges batch efficiently today |
-| `flush` (steady-state, 1 pending write) | p50 8ms · p95 10ms | p50 45ms · p95 52ms | durability-only since 8.9.0 — cost no longer depends on history backlog or retention mode |
-
-**The honest note on bulk writes:** `addMany` today commits each item as its own
-generation (the same durability as single-op `add`, serialized by the single-writer
-lock), so bulk-load cost is N × single-op cost. Batched chunk commits (one generation
-and one fsync window per chunk, as `removeMany` already does) are designed into the
-unified-commit work on the current roadmap. Until that ships, size bulk imports
-accordingly — 10k entities is minutes, not seconds, on filesystem storage.
-
-## Open / close
-
-| Operation | 1,000 entities | 10,000 entities | Notes |
-|---|---|---|---|
-| `open` (empty store) | ~560ms | ~190ms | includes embedder initialization |
-| `open` (warm, populated, clean shutdown) | 763ms | 4.9s | pure-JS vector index load dominates and grows with entity count; the native accelerator exists precisely to remove this |
-| `close` | bounded | bounded | auto-compaction pass is time-bounded (~5s max) since 8.9.0 |
-
-A store that was NOT cleanly closed pays index rebuilds on top of the warm-open
-number (tens of seconds at 10k) — clean shutdown is worth engineering for.
-
-## How these were produced
-
- **Hardware**: Intel Core i9-14900HX (32 threads), 62GB RAM, NVMe, Linux, Node v22.
- **Backend**: `storage: { type: 'filesystem' }`, pure JS (no native providers).
- **Embeddings**: deterministic stub for non-semantic ops (isolates engine cost);
-  the real WASM embedder for the semantic row (that's what you'll run).
- **Method**: p50/p95 over 50–200 samples per op against the built `dist/`;
-  the measuring script ships in the repo history and re-runs per release.
-
-Numbers on different hardware will differ; the *shape* (sub-2ms indexed reads,
-~160ms embedding-bound semantic queries, durability-priced writes) is the envelope
-you should hold your deployment against. If your measurements diverge from these
-shapes by an order of magnitude, something is wrong — file it.
--- a/package-lock.json
+++ b/package-lock.json
@ -1,12 +1,12 @@
 {
  "name": "@soulcraft/brainy",
-  "version": "8.9.0",
+  "version": "8.8.1",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "@soulcraft/brainy",
-      "version": "8.9.0",
+      "version": "8.8.1",
      "license": "MIT",
      "dependencies": {
        "@msgpack/msgpack": "^3.1.2",
--- a/package.json
+++ b/package.json
@ -1,6 +1,6 @@
 {
  "name": "@soulcraft/brainy",
-  "version": "8.9.0",
+  "version": "8.8.1",
  "description": "Universal Knowledge Protocol™ - World's first Triple Intelligence database unifying vector, graph, and document search in one API. Stage 3 CANONICAL: 42 nouns × 127 verbs covering 96-97% of all human knowledge.",
  "main": "dist/index.js",
  "module": "dist/index.js",
--- a/scripts/push-docs.js
+++ b/scripts/push-docs.js
@ -1,116 +0,0 @@
-#!/usr/bin/env node
-/**
- * @module scripts/push-docs
- * @description Push this repo's PUBLIC docs to the soulcraft.com docs ingest
- * door after an npm publish (VENUE-DOCS-RELEASE-PUSH — retires the old
- * build-time docs sync).
- *
- * Contract (mirrors the reference implementation on the serving side):
- *   POST {base}/api/docs/ingest
- *   headers: x-service-secret: $DOCS_INGEST_SECRET, Content-Type: application/json
- *   body: { docs: [{ slug, title, markdown, nav: { order, section } }] }
- *   batches of 10, idempotent per slug.
- *
- * A doc is public iff its frontmatter has `public: true` AND a `slug`. The
- * frontmatter is stripped; `category` → nav.section, `order` → nav.order.
- *
- * Deliberately NOT pushed: the combined /docs landing index. It spans BOTH
- * engine corpora (this repo's and the native accelerator's), so a per-repo
- * push would clobber the union — the index is authored on the serving side.
- *
- * Env: DOCS_INGEST_SECRET (required), DOCS_INGEST_BASE (default
- * https://soulcraft.com). Exits 0 with a LOUD warning when the secret is
- * absent (the npm publish has already happened; the serving side runs its
- * interim sync on request) and exits 1 when a push actually fails — the docs
- * site would silently trail npm otherwise, and that must be visible.
- */
-import * as fs from 'node:fs'
-import * as path from 'node:path'
-
-const BASE = (process.env.DOCS_INGEST_BASE || 'https://soulcraft.com').replace(/\/+$/, '')
-const SECRET = process.env.DOCS_INGEST_SECRET
-const DOCS_DIR = path.join(path.dirname(new URL(import.meta.url).pathname), '..', 'docs')
-const BATCH = 10
-
-if (!SECRET) {
-  console.warn(
-    '⚠️  DOCS PUSH SKIPPED: DOCS_INGEST_SECRET is not set.\n' +
-      '    soulcraft.com/docs now TRAILS this npm release until docs are pushed.\n' +
-      '    Either export DOCS_INGEST_SECRET and re-run `node scripts/push-docs.js`,\n' +
-      '    or ping venue on VENUE-DOCS-RELEASE-PUSH for the interim sync.'
-  )
-  process.exit(0)
-}
-
-/** Minimal frontmatter split — returns [meta, body] or [null, raw]. */
-function parseFrontmatter(raw) {
-  const m = raw.match(/^---\n([\s\S]*?)\n---\n([\s\S]*)$/)
-  if (!m) return [null, raw]
-  const meta = {}
-  for (const line of m[1].split('\n')) {
-    const kv = line.match(/^(\w[\w-]*):\s*(.*)$/)
-    if (kv) meta[kv[1]] = kv[2].trim().replace(/^["']|["']$/g, '')
-  }
-  return [meta, m[2]]
-}
-
-const docs = []
-;(function walk(dir) {
-  for (const entry of fs.readdirSync(dir, { withFileTypes: true })) {
-    const full = path.join(dir, entry.name)
-    if (entry.isDirectory()) walk(full)
-    else if (entry.name.endsWith('.md')) {
-      const [meta, body] = parseFrontmatter(fs.readFileSync(full, 'utf-8'))
-      if (!meta || meta.public !== 'true' || !meta.slug) continue
-      docs.push({
-        slug: meta.slug,
-        title: meta.title || meta.slug,
-        markdown: body.trim(),
-        nav: {
-          order: Number.parseInt(meta.order || '99', 10) || 99,
-          section: meta.category || 'guides'
-        }
-      })
-    }
-  }
-})(DOCS_DIR)
-
-if (docs.length === 0) {
-  console.error('❌ DOCS PUSH FAILED: zero public docs collected — refusing to push an empty corpus.')
-  process.exit(1)
-}
-docs.sort((a, b) => a.slug.localeCompare(b.slug))
-console.log(`Pushing ${docs.length} public docs to ${BASE}/api/docs/ingest …`)
-
-let failed = false
-for (let i = 0; i < docs.length; i += BATCH) {
-  const batch = docs.slice(i, i + BATCH)
-  try {
-    const res = await fetch(`${BASE}/api/docs/ingest`, {
-      method: 'POST',
-      headers: {
-        'x-service-secret': SECRET,
-        'Content-Type': 'application/json',
-        'User-Agent': 'brainy-docs-push/1.0'
-      },
-      body: JSON.stringify({ docs: batch }),
-      signal: AbortSignal.timeout(120_000)
-    })
-    if (!res.ok) {
-      throw new Error(`HTTP ${res.status}: ${(await res.text()).slice(0, 300)}`)
-    }
-    console.log(`  batch ${i / BATCH + 1}: ${batch.map((d) => d.slug).join(', ')} → ok`)
-  } catch (err) {
-    failed = true
-    console.error(`  batch ${i / BATCH + 1} FAILED: ${err instanceof Error ? err.message : err}`)
-  }
-}
-
-if (failed) {
-  console.error(
-    '❌ DOCS PUSH INCOMPLETE — soulcraft.com/docs may trail npm. ' +
-      'Re-run `node scripts/push-docs.js` or ping venue on VENUE-DOCS-RELEASE-PUSH.'
-  )
-  process.exit(1)
-}
-console.log('✅ Docs pushed.')
--- a/scripts/release.sh
+++ b/scripts/release.sh
@ -196,18 +196,6 @@ else
 fi
 echo -e "${GREEN}✅ GitHub release created${NC}\n"

-# Step 12: Push public docs to the soulcraft.com docs ingest door
-# (VENUE-DOCS-RELEASE-PUSH). Skips with a loud warning when
-# DOCS_INGEST_SECRET is unset; fails loudly (without undoing the publish —
-# that already happened) when a push errors, so the docs site never
-# silently trails npm.
-echo -e "${BLUE}1️⃣2️⃣ Pushing public docs to soulcraft.com/docs...${NC}"
-if node scripts/push-docs.js; then
-  echo -e "${GREEN}✅ Docs push step done${NC}\n"
-else
-  echo -e "${RED}❌ Docs push FAILED — soulcraft.com/docs trails npm until re-run or interim sync${NC}\n"
-fi
-
 echo -e "${GREEN}━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━${NC}"
 echo -e "${GREEN}🎉 Release ${NEW_VERSION} complete!${NC}"
 echo -e "${GREEN}━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━${NC}"
--- a/src/aggregation/AggregationIndex.ts
+++ b/src/aggregation/AggregationIndex.ts
@ -88,18 +88,10 @@ function matchesSource(entity: Record<string, unknown>, source: AggregateDefinit
    if (entity.service !== source.service) return false
  }

-  // Where filter — resolve each filtered field through resolveEntityField,
-  // the SAME single source of truth groupBy uses (top-level standard fields
-  // + custom metadata). Matching only the metadata sub-object made
-  // where:{subtype}/{visibility}/… a silent no-op: reserved fields never
-  // live in the custom bag, so those filters could never match anything.
+  // Metadata where filter — match against the entity's metadata sub-object
  if (source.where && Object.keys(source.where).length > 0) {
-    const e = entity as unknown as HNSWNounWithMetadata
-    const resolved: Record<string, unknown> = {}
-    for (const key of Object.keys(source.where)) {
-      resolved[key] = resolveEntityField(e, key)
-    }
-    if (!matchesMetadataFilter(resolved, source.where)) return false
+    const metadata = (entity.metadata ?? entity) as Record<string, unknown>
+    if (!matchesMetadataFilter(metadata, source.where)) return false
  }

  return true
--- a/src/brainy.ts
+++ b/src/brainy.ts
@ -396,15 +396,6 @@ export type IndexFamily = 'vector' | 'metadata' | 'graph'
 */
 const AGGREGATION_BACKFILL_RETRY_COOLDOWN_MS = 30_000

-/**
- * Time budget for the auto-compaction pass at close() (8.9.0). Bounds how long
- * a clean shutdown spends reclaiming history backlog — an early stop is a
- * consistent prefix and the next close/explicit pass resumes. Explicit
- * `compactHistory()` calls are unbounded unless the caller passes their own
- * `timeBudgetMs` (maintenance windows choose their own budgets).
- */
-const CLOSE_COMPACTION_BUDGET_MS = 5_000
-
 /**
 * The main Brainy class - Clean, Beautiful, Powerful
 * REAL IMPLEMENTATION - No stubs, no mocks
@ -1892,29 +1883,6 @@ export class Brainy<T = any> implements BrainyInterface<T> {
    }
  }

-  /**
-   * @description Build the AGGREGATION view of an entity from a stored flat
-   * metadata record — EVERY reserved field mapped to its top-level entity
-   * name (stored `noun` → `type`), custom metadata in `metadata`. This must
-   * mirror the add-path `entityForIndexing` shape exactly: the aggregation
-   * engine resolves groupBy/where fields via `resolveEntityField`
-   * (top-level standard fields + custom metadata), so a view that drops a
-   * reserved field makes every aggregate grouped by that field decrement a
-   * group that does not exist — counts then drift upward forever after
-   * deletes (SELF-AGGREGATE-DELETE-DRIFT). Do not hand-roll subsets of this.
-   * @param record - The stored flat metadata record (before-image or pre-delete read).
-   * @returns The full-fidelity entity view for aggregation hooks.
-   */
-  private entityForAggFromRawRecord(record: Record<string, unknown>): Record<string, unknown> {
-    const { reserved, custom } = splitNounMetadataRecord(record)
-    const { noun, ...rest } = reserved
-    return {
-      type: noun,
-      ...rest,
-      metadata: custom
-    }
-  }
-
  /**
   * @description Add an entity (noun) to the brain. Embeds `data` into a vector and
   * indexes the entity across all three intelligences — vector similarity, graph
@ -3157,16 +3125,15 @@ export class Brainy<T = any> implements BrainyInterface<T> {
          ]
        : undefined)

-      // Aggregation hook (outside transaction — derived data). `existing` is
-      // the full get() view — every reserved field top-level — and must be
-      // passed whole: a subset view makes the old-side decrement miss any
-      // reserved-field group (update would then double-count it).
+      // Aggregation hook (outside transaction — derived data)
      if (this._aggregationIndex) {
-        this._aggregationIndex.onEntityUpdated(
-          params.id,
-          entityForIndexing,
-          existing as unknown as Record<string, unknown>
-        )
+        const oldEntityForAgg = {
+          type: existing.type,
+          service: existing.service,
+          data: existing.data,
+          metadata: existing.metadata
+        }
+        this._aggregationIndex.onEntityUpdated(params.id, entityForIndexing, oldEntityForAgg)
      }
  }

@ -3278,15 +3245,19 @@ export class Brainy<T = any> implements BrainyInterface<T> {
          ]
        : undefined)

-      // Aggregation hook (outside transaction — derived data). The view must
-      // carry EVERY reserved field top-level (not a subset): a groupBy on
-      // subtype/visibility/etc. otherwise decrements a nonexistent group and
-      // the real count never comes down.
+      // Aggregation hook (outside transaction — derived data)
      if (this._aggregationIndex && metadata) {
-        this._aggregationIndex.onEntityDeleted(
-          id,
-          this.entityForAggFromRawRecord(metadata as Record<string, unknown>)
-        )
+        // Reconstruct entity-like object from stored metadata via the
+        // canonical reserved/custom split (the hand-rolled destructure here
+        // missed subtype/_rev, leaking them into the aggregation view).
+        const { reserved, custom } = splitNounMetadataRecord(metadata)
+        const entityForAgg = {
+          type: reserved.noun,
+          service: reserved.service,
+          data: reserved.data,
+          metadata: custom
+        }
+        this._aggregationIndex.onEntityDeleted(id, entityForAgg)
      }
  }

@ -6914,30 +6885,6 @@ export class Brainy<T = any> implements BrainyInterface<T> {
    this.assertWritable('removeMany')
    await this.ensureInitialized()

-    // Loud selector validation: a call with no usable selector used to
-    // resolve successfully having deleted NOTHING (total: 0) — the classic
-    // silent no-op being a bare array passed positionally
-    // (removeMany([id]) instead of removeMany({ ids: [id] })). The caller
-    // believes the delete happened; every count derived afterwards is "wrong"
-    // while the engine was never even asked. Refuse instead.
-    if (Array.isArray(params)) {
-      throw new Error(
-        `removeMany() takes a params object, not a bare array — use removeMany({ ids: [...] })`
-      )
-    }
-    if (!params || (!params.ids && !params.type && !params.where)) {
-      throw new Error(
-        `removeMany() requires a selector: { ids } and/or { type, where }. ` +
-          `An empty selector would silently delete nothing — refusing.`
-      )
-    }
-    if (params.ids && params.ids.length === 0) {
-      throw new Error(
-        `removeMany() received ids: [] — an empty id list deletes nothing. ` +
-          `Pass the ids to delete, or omit ids and select by { type, where }.`
-      )
-    }
-
    // Determine what to delete
    let idsToDelete: string[] = []

@ -8265,27 +8212,6 @@ export class Brainy<T = any> implements BrainyInterface<T> {
    return this.generationStore.compact(options)
  }

-  /**
-   * @description Repack cold generation history into sealed segments —
-   * re-representation, never deletion: every record and delta stays readable
-   * (`asOf()` unchanged); the physical file count drops by orders of
-   * magnitude. Runs automatically (time-bounded) at `close()`; call this for
-   * explicit maintenance windows on long-lived writers. The ONLY history
-   * transform permitted under the archival profile (`retention: 'all'`).
-   * @param options - `timeBudgetMs` bounds the pass (early stop = consistent
-   *   prefix, next pass resumes); `batchGenerations` sizes each fold.
-   * @returns Folded generation count and segments created.
-   */
-  async repackHistory(options?: {
-    timeBudgetMs?: number
-    batchGenerations?: number
-  }): Promise<{ foldedGenerations: number; segmentsCreated: number }> {
-    this.assertWritable('repackHistory')
-    await this.ensureInitialized()
-    await this.generationStore.flushPendingSingleOps()
-    return this.generationStore.repackHistory(options)
-  }
-
  /**
   * @description Read-only generational-history footprint for fleet audits:
   * generation count, total on-disk bytes, generation/timestamp range, the
@ -8313,24 +8239,6 @@ export class Brainy<T = any> implements BrainyInterface<T> {
    }
  }

-  /**
-   * @description A deterministic content digest of the generation log through
-   * `g` (D8 — gate-to-generation provenance): identical history produces the
-   * identical digest on any machine; divergence produces a different one.
-   * Release gates and suite verdicts pin `{generation, digest}` and verify
-   * both at execution time instead of pinning a git commit. O(segments +
-   * live-tier window), never O(all generations). Throws `RangeError` out of
-   * range and `GenerationCompactedError` below the horizon — a gate can
-   * never silently pin reclaimed history.
-   * @example
-   * const gate = { generation: brain.generation(), digest: await brain.generationDigest(brain.generation()) }
-   */
-  async generationDigest(g: number): Promise<string> {
-    await this.ensureInitialized()
-    await this.generationStore.flushPendingSingleOps()
-    return this.generationStore.generationDigest(g)
-  }
-
  /**
   * @description Drive the adaptive retention byte budget at runtime — the
   * settable input a machine-level coordinator (e.g. cor's `ResourceManager`,
@ -8410,24 +8318,19 @@ export class Brainy<T = any> implements BrainyInterface<T> {

  /**
   * @description Run history compaction under the resolved `retention` policy
-   * when `autoCompact` is on (the default). Invoked from `close()` ONLY
-   * (8.9.0) — flush() is durability work and never pays maintenance costs; a
-   * production deployment measured reclaim-on-flush blocking single writes
-   * for 25-191s under memory pressure. Long-lived writers that never close
-   * accumulate history until their next explicit `compactHistory()` — the
-   * documented trade: predictable writes, explicit maintenance.
+   * when `autoCompact` is on (the default). Invoked from `flush()` and
+   * `close()` so generational record-sets cannot accumulate unbounded across a
+   * long-lived writer's lifetime.
   *
   * - `'all'` → returns without reclaiming (index compaction for speed still
   *   runs elsewhere; history is decoupled and kept).
   * - `'adaptive'` → reclaim oldest-unpinned history down to the byte budget.
   * - `'explicit'` → apply the supplied `maxGenerations`/`maxAge`/`maxBytes` caps.
   *
-   * Every auto pass is TIME-BOUNDED ({@link CLOSE_COMPACTION_BUDGET_MS}) so a
-   * large backlog can never stall a clean shutdown; the next pass resumes.
   * Read-only instances and an explicit `autoCompact: false` skip silently.
   * Pinned generations are never reclaimed ({@link GenerationStore.compact}).
   * Failures are logged and swallowed — compaction is housekeeping and must
-   * never fail a clean shutdown.
+   * never fail a flush or a clean shutdown.
   */
  private async autoCompactHistory(): Promise<void> {
    // Nothing to compact on a read-only instance or before init wired up the
@ -8443,16 +8346,12 @@ export class Brainy<T = any> implements BrainyInterface<T> {
      if (policy.mode === 'adaptive') {
        const budget = this.adaptiveHistoryBudgetBytes(policy.budgetBytes)
        if (budget === Infinity) return // no pressure signal → keep everything this pass
-        await this.generationStore.compact({
-          maxBytes: budget,
-          timeBudgetMs: CLOSE_COMPACTION_BUDGET_MS
-        })
+        await this.generationStore.compact({ maxBytes: budget })
      } else {
        await this.generationStore.compact({
          maxGenerations: policy.maxGenerations,
          maxAge: policy.maxAge,
-          maxBytes: policy.maxBytes,
-          timeBudgetMs: CLOSE_COMPACTION_BUDGET_MS
+          maxBytes: policy.maxBytes
        })
      }
    } catch (error) {
@ -9489,9 +9388,12 @@ export class Brainy<T = any> implements BrainyInterface<T> {
    )
    plan.touchedNouns.push(params.id)

-    // The full planGetEntity view, passed whole — a subset view makes the
-    // old-side decrement miss reserved-field groups (double-count on update).
-    const oldEntityForAgg = existing as unknown as Record<string, unknown>
+    const oldEntityForAgg = {
+      type: existing.type,
+      service: existing.service,
+      data: existing.data,
+      metadata: existing.metadata
+    }
    plan.postCommit.push(() => {
      if (this._aggregationIndex) {
        this._aggregationIndex.onEntityUpdated(params.id, entityForIndexing, oldEntityForAgg)
@ -9612,9 +9514,14 @@ export class Brainy<T = any> implements BrainyInterface<T> {
    }

    if (metadata) {
-      // Mirror of remove()'s aggregation hook — the FULL reserved view, so
-      // reserved-field groupBy decrements find their group.
-      const entityForAgg = this.entityForAggFromRawRecord(metadata as Record<string, unknown>)
+      // Canonical reserved/custom split — mirror of remove()'s aggregation hook.
+      const { reserved, custom } = splitNounMetadataRecord(metadata)
+      const entityForAgg = {
+        type: reserved.noun,
+        service: reserved.service,
+        data: reserved.data,
+        metadata: custom
+      }
      plan.postCommit.push(() => {
        if (this._aggregationIndex) {
          this._aggregationIndex.onEntityDeleted(id, entityForAgg)
@ -10597,14 +10504,12 @@ export class Brainy<T = any> implements BrainyInterface<T> {
      this.generationStore.persistCounterNow()
    ])

-    // NOTE (8.9.0): flush() no longer compacts history. Flush is DURABILITY
-    // work — it must cost what this window's deltas cost, never what the
-    // history backlog costs. Auto-compaction (a MAINTENANCE concern) runs at
-    // close() and via explicit compactHistory(); a production deployment
-    // measured reclaim-on-flush stalling single writes for 25-191s under
-    // memory pressure, which is exactly the class this separation ends.
+    // 6. Auto-compact generational history per config.retention (default on).
+    //    Runs after the flush so durable state is in place; respects live
+    //    Db pins and an explicit autoCompact: false.
+    await this.autoCompactHistory()

-    // 6. Stamp the entity tree: which source generation the canonical tree
+    // 7. Stamp the entity tree: which source generation the canonical tree
    //    reflects + the rollup invariants that verify it whole (the counters
    //    persisted in step 1). Written at flush boundaries — the tree tracks
    //    every commit by construction, so the stamp is a durable checkpoint,
@ -16231,21 +16136,9 @@ export class Brainy<T = any> implements BrainyInterface<T> {
      await this.generationStore.flushPendingSingleOps()
    }

-    // Phase 0b: REPACK cold history into sealed segments (D1+D3 —
-    // re-representation, never deletion; the only history transform under the
-    // archival profile), then auto-compact per config.retention. Repack runs
-    // FIRST so bounded-retention reclaim can drop whole segments. Both are
-    // time-bounded maintenance passes (8.9.0 law: flush() never pays these);
-    // both are housekeeping — failures warn, never fail a clean shutdown.
-    if (!this.isReadOnly && this.generationStore) {
-      try {
-        await this.generationStore.repackHistory({ timeBudgetMs: 5_000 })
-      } catch (error) {
-        console.warn(
-          `History repacking failed (non-fatal): ${error instanceof Error ? error.message : String(error)}`
-        )
-      }
-    }
+    // Phase 0b: Auto-compact generational history per config.retention (default
+    // on) BEFORE the generation store closes below. Respects live Db pins and
+    // an explicit autoCompact: false; no-op on read-only instances.
    await this.autoCompactHistory()

    // Phase 1: Flush ALL components in parallel to persist buffered data
--- a/src/db/factLog.ts
+++ b/src/db/factLog.ts
@ -102,26 +102,12 @@ export interface FactScanBatch {
  segmentId: string
 }

-/**
- * Liveness bound on a scan's FIRST batch (Stage-2 co-freeze, D1 contract):
- * `batches()` must yield its first batch — or fail loudly — within this many
- * ms of the first pull. A backlogged or damaged store may be SLOW, but it may
- * never be SILENT: a consumer awaiting the first batch is otherwise
- * indistinguishable from a wedge (the exact failure shape a production heal
- * hit against a generations-backlogged brain).
- */
-export const SCANFACTS_FIRST_BATCH_MS = 10_000
-
 /** The telemetry a scan OPEN returns (frozen shape). */
 export interface FactScanHandle {
  headGeneration: number
  segmentCount: number
  approxFactCount: number
-  /**
-   * Ordered batches; a detected gap aborts LOUDLY, never a silent skip.
-   * Liveness contract: the FIRST batch resolves or rejects within
-   * {@link SCANFACTS_FIRST_BATCH_MS} of the first pull — never a silent hang.
-   */
+  /** Ordered batches; a detected gap aborts LOUDLY, never a silent skip. */
  batches: () => AsyncGenerator<FactScanBatch>
  /** Close telemetry — the invariant cross-check, valid after iteration ends. */
  summary: () => { factsYielded: number; segmentsRead: number }
@ -454,8 +440,6 @@ export class FactLog {
    toGeneration?: number
    kinds?: Array<'noun' | 'verb'>
    batchSize?: number
-    /** Test override for the first-batch liveness bound (default {@link SCANFACTS_FIRST_BATCH_MS}). */
-    firstBatchTimeoutMs?: number
  }): FactScanHandle {
    const from = options?.fromGeneration ?? 1
    const to = options?.toGeneration ?? this.head
@ -530,43 +514,11 @@ export class FactLog {
      }
    }

-    // Liveness wrapper: the FIRST pull races the contract deadline. Only the
-    // first — the bound is time-to-first-batch (proof the producer is alive),
-    // not per-batch pacing; and it runs only while a pull is actually pending,
-    // so consumer think-time between pulls never counts against the producer.
-    const firstBatchTimeoutMs = options?.firstBatchTimeoutMs ?? SCANFACTS_FIRST_BATCH_MS
-    async function* batchesWithLiveness(this: void): AsyncGenerator<FactScanBatch> {
-      const inner = batches()
-      let timer: NodeJS.Timeout | undefined
-      try {
-        const deadline = new Promise<never>((_, reject) => {
-          timer = setTimeout(
-            () =>
-              reject(
-                new Error(
-                  `fact log: scanFacts produced no first batch within ${firstBatchTimeoutMs}ms ` +
-                    `(liveness contract) — the store is wedged or unreadably slow; aborting scan LOUDLY ` +
-                    `instead of hanging the consumer.`
-                )
-              ),
-            firstBatchTimeoutMs
-          )
-          timer.unref?.()
-        })
-        const first = await Promise.race([inner.next(), deadline])
-        if (first.done) return
-        yield first.value
-      } finally {
-        clearTimeout(timer)
-      }
-      yield* inner
-    }
-
    return {
      headGeneration: this.head,
      segmentCount: segments.length + (tailSnapshot.length > 0 ? 1 : 0),
      approxFactCount,
-      batches: batchesWithLiveness,
+      batches,
      summary: () => ({ factsYielded, segmentsRead })
    }
  }
--- a/src/db/generationSegments.ts
+++ b/src/db/generationSegments.ts
@ -1,459 +0,0 @@
-/**
- * @module db/generationSegments
- * @description The generation-segment store — Stage-2 D1+D3+repacking's file
- * format (co-frozen 2026-07-19; design: the d1-d3-repacking spec).
- *
- * Packs CONSECUTIVE cold generations' record-sets (before-images + delta)
- * into append-once segment files with derived sidecar indexes, so history
- * scales in SEGMENTS (tens) instead of FILES-PER-GENERATION (hundreds of
- * thousands), and cold-open reads ONE manifest instead of listing the
- * backlog. Layout under `_generations/segments/`:
- *
- * - `seg-<firstGen, zero-padded 20>.bgs` — magic "BGS1", then one frame per
- *   generation: `u32 payloadLen | u32 crc32c | msgpack payload`. Payload is
- *   POSITIONAL: `[generation, timestamp, delta, records[], flags]` with
- *   records `[kindByte, id, record]`. `flags` reserves encoding evolution
- *   (bit 0 = compressed payload — v1 always 0; a future writer upgrade,
- *   never a format break). Sealed segments are IMMUTABLE — the fact log's
- *   own law, generalized.
- * - `seg-<firstGen>.idx` — DERIVED sidecar (msgpack): per-generation frame
- *   offsets (point reads = one ranged read, never a listing) + per-id
- *   generation postings (per-id chain rebuilds read only what they need).
- *   Corrupt/missing → rebuilt from its segment in one sequential read,
- *   loudly.
- * - `manifest.json` — the segment catalogue + `compactedBelow` (D3's
- *   horizon marker). Cold-open reads THIS; the packed backlog is never
- *   listed.
- *
- * D3 semantics carried here: bounded-retention reclaim drops WHOLE segments
- * at boundaries (O(1) per segment, no rewrite); under the archival profile
- * (`retention: 'all'`) nothing here is ever dropped — folding is the only
- * transform (re-representation, never deletion).
- */
-
-import { encode as msgpackEncode, decode as msgpackDecode } from '@msgpack/msgpack'
-import { crc32c } from '../utils/crc32c.js'
-import type { FactLogStorage } from './factLog.js'
-import { prodLog } from '../utils/logger.js'
-
-/** Directory for segment files + manifest, under the generations prefix. */
-export const SEGMENTS_PREFIX = '_generations/segments'
-
-/** Target sealed-segment size (co-freeze proposal; tunable on evidence). */
-export const SEGMENT_TARGET_BYTES = 64 * 1024 * 1024
-
-const MAGIC = new TextEncoder().encode('BGS1')
-const FRAME_PREFIX_BYTES = 8 // u32 payloadLen + u32 crc32c
-const MANIFEST_PATH = `${SEGMENTS_PREFIX}/manifest.json`
-
-/** One generation's fold input — exactly what the live tier holds for it. */
-export interface FoldGeneration {
-  generation: number
-  timestamp: number
-  /** The tx.json delta object, carried verbatim. */
-  delta: unknown
-  /** The before-image record-set (empty for record-less generations). */
-  records: Array<{ kind: 'noun' | 'verb'; id: string; record: unknown }>
-}
-
-/** Manifest entry for one sealed segment. */
-export interface SegmentMeta {
-  file: string
-  firstGeneration: number
-  lastGeneration: number
-  frames: number
-  bytes: number
-  /** crc32c of the full segment byte stream — the digest chain's link. */
-  checksum: number
-}
-
-interface SegmentManifest {
-  version: 1
-  compactedBelow: number
-  segments: SegmentMeta[]
-}
-
-interface SidecarIndex {
-  version: 1
-  /** [generation, frameOffset, frameLen] ascending by generation. */
-  generations: Array<[number, number, number]>
-  /** `${kindByte}:${id}` → ascending generations holding a record for it. */
-  ids: Record<string, number[]>
-}
-
-const segmentFileName = (firstGeneration: number): string =>
-  `seg-${String(firstGeneration).padStart(20, '0')}.bgs`
-const sidecarFileName = (firstGeneration: number): string =>
-  `seg-${String(firstGeneration).padStart(20, '0')}.idx`
-
-/**
- * The generation-segment store. Owns the packed tier ONLY — the live
- * per-generation tier and the routing between tiers belong to
- * `GenerationStore`. All mutating entry points here are called under the
- * generation store's commit mutex.
- */
-export class GenerationSegmentStore {
-  private readonly storage: FactLogStorage
-  private manifest: SegmentManifest = { version: 1, compactedBelow: 0, segments: [] }
-  /** Sidecar cache — segments are immutable, so entries never invalidate. */
-  private readonly sidecars = new Map<string, SidecarIndex>()
-
-  constructor(storage: FactLogStorage) {
-    this.storage = storage
-  }
-
-  /** Load the manifest (ONE read — never a directory listing). */
-  async open(): Promise<void> {
-    const raw = (await this.storage.readRawObject(MANIFEST_PATH)) as SegmentManifest | null
-    if (raw) {
-      if (raw.version !== 1) {
-        throw new Error(
-          `[GenerationSegments] manifest version ${String(raw.version)} is newer than this ` +
-            `engine understands — refusing to serve partial history. Upgrade the engine.`
-        )
-      }
-      this.manifest = raw
-    }
-  }
-
-  /** The packed tier's catalogue (ascending, immutable snapshot). */
-  segments(): readonly SegmentMeta[] {
-    return this.manifest.segments
-  }
-
-  /** D3's horizon marker: generations below this were reclaimed (bounded profiles only). */
-  compactedBelow(): number {
-    return this.manifest.compactedBelow
-  }
-
-  /** The covering sealed segment for `gen`, or null if it lives outside the packed tier. */
-  private coveringSegment(gen: number): SegmentMeta | null {
-    // Manifest is ascending and ranges never overlap — binary search.
-    const segs = this.manifest.segments
-    let lo = 0
-    let hi = segs.length - 1
-    while (lo <= hi) {
-      const mid = (lo + hi) >> 1
-      const s = segs[mid]
-      if (gen < s.firstGeneration) hi = mid - 1
-      else if (gen > s.lastGeneration) lo = mid + 1
-      else return s
-    }
-    return null
-  }
-
-  /** True when `gen` is packed (readable from this tier). */
-  hasGeneration(gen: number): boolean {
-    return this.coveringSegment(gen) !== null
-  }
-
-  /**
-   * Fold consecutive generations into ONE new sealed segment + sidecar and
-   * append it to the manifest atomically. Caller guarantees: `gens` is
-   * ascending, contiguous with the packed tier (first = last packed + 1 when
-   * segments exist), and already durable in the live tier. Crash between the
-   * segment write and the caller's live-tier delete leaves a DUPLICATE
-   * representation — resolved live-tier-wins by the reader; never a gap.
-   */
-  async fold(gens: FoldGeneration[]): Promise<SegmentMeta> {
-    if (gens.length === 0) {
-      throw new Error('[GenerationSegments] fold() requires at least one generation')
-    }
-    for (let i = 1; i < gens.length; i++) {
-      if (gens[i].generation <= gens[i - 1].generation) {
-        throw new Error('[GenerationSegments] fold() input must be strictly ascending')
-      }
-    }
-    const last = this.manifest.segments[this.manifest.segments.length - 1]
-    if (last && gens[0].generation <= last.lastGeneration) {
-      throw new Error(
-        `[GenerationSegments] fold() overlaps the packed tier: ${gens[0].generation} ≤ ` +
-          `sealed ${last.lastGeneration} — segments are immutable, never rewritten`
-      )
-    }
-
-    const first = gens[0].generation
-    const file = segmentFileName(first)
-    const sidecar: SidecarIndex = { version: 1, generations: [], ids: {} }
-
-    // Encode all frames, tracking offsets for the sidecar.
-    const parts: Uint8Array[] = [MAGIC]
-    let offset = MAGIC.length
-    for (const g of gens) {
-      const payload = msgpackEncode([
-        g.generation,
-        g.timestamp,
-        g.delta,
-        g.records.map((r) => [r.kind === 'noun' ? 0 : 1, r.id, r.record]),
-        0 // flags: v1 = uncompressed
-      ])
-      const frame = new Uint8Array(FRAME_PREFIX_BYTES + payload.length)
-      const view = new DataView(frame.buffer)
-      view.setUint32(0, payload.length, true)
-      view.setUint32(4, crc32c(payload), true)
-      frame.set(payload, FRAME_PREFIX_BYTES)
-      sidecar.generations.push([g.generation, offset, frame.length])
-      for (const r of g.records) {
-        const key = `${r.kind === 'noun' ? 0 : 1}:${r.id}`
-        ;(sidecar.ids[key] ??= []).push(g.generation)
-      }
-      parts.push(frame)
-      offset += frame.length
-    }
-    const total = parts.reduce((n, p) => n + p.length, 0)
-    const bytes = new Uint8Array(total)
-    let at = 0
-    for (const p of parts) {
-      bytes.set(p, at)
-      at += p.length
-    }
-
-    const meta: SegmentMeta = {
-      file,
-      firstGeneration: first,
-      lastGeneration: gens[gens.length - 1].generation,
-      frames: gens.length,
-      bytes: total,
-      checksum: crc32c(bytes)
-    }
-
-    // Durability order: segment + sidecar fsync'd BEFORE the manifest names
-    // them (a crash before the manifest = invisible orphan files, harmless);
-    // manifest last, atomically.
-    const segPath = `${SEGMENTS_PREFIX}/${file}`
-    const idxPath = `${SEGMENTS_PREFIX}/${sidecarFileName(first)}`
-    await this.storage.writeRawBytes(segPath, bytes)
-    await this.storage.writeRawBytes(idxPath, msgpackEncode(sidecar))
-    await this.storage.syncRawObjects([segPath, idxPath])
-    const next: SegmentManifest = {
-      ...this.manifest,
-      segments: [...this.manifest.segments, meta]
-    }
-    await this.storage.writeRawObject(MANIFEST_PATH, next)
-    await this.storage.syncRawObjects([MANIFEST_PATH])
-    this.manifest = next
-    this.sidecars.set(file, sidecar)
-    return meta
-  }
-
-  /** Load (or rebuild, loudly) a segment's sidecar. */
-  private async sidecarFor(meta: SegmentMeta): Promise<SidecarIndex> {
-    const cached = this.sidecars.get(meta.file)
-    if (cached) return cached
-    const idxPath = `${SEGMENTS_PREFIX}/${sidecarFileName(meta.firstGeneration)}`
-    const raw = await this.storage.readRawBytes(idxPath)
-    if (raw) {
-      try {
-        const idx = msgpackDecode(raw) as SidecarIndex
-        if (idx.version === 1) {
-          this.sidecars.set(meta.file, idx)
-          return idx
-        }
-      } catch {
-        // fall through to rebuild
-      }
-    }
-    // Sidecars are DERIVED: rebuild from the segment, loudly — never serve
-    // wrong offsets silently.
-    prodLog.warn(
-      `[GenerationSegments] sidecar for ${meta.file} missing or unreadable — rebuilding from the segment`
-    )
-    const rebuilt = await this.rebuildSidecar(meta)
-    await this.storage.writeRawBytes(idxPath, msgpackEncode(rebuilt))
-    this.sidecars.set(meta.file, rebuilt)
-    return rebuilt
-  }
-
-  /** One sequential read of the segment → a fresh sidecar. Verifies every frame CRC. */
-  private async rebuildSidecar(meta: SegmentMeta): Promise<SidecarIndex> {
-    const frames = await this.readAllFrames(meta)
-    const idx: SidecarIndex = { version: 1, generations: [], ids: {} }
-    for (const f of frames) {
-      idx.generations.push([f.generation, f.offset, f.frameLen])
-      for (const r of f.records) {
-        const key = `${r.kind === 'noun' ? 0 : 1}:${r.id}`
-        ;(idx.ids[key] ??= []).push(f.generation)
-      }
-    }
-    return idx
-  }
-
-  private decodeFrame(
-    payload: Uint8Array
-  ): { generation: number; timestamp: number; delta: unknown; records: FoldGeneration['records'] } {
-    const [generation, timestamp, delta, rawRecords] = msgpackDecode(payload) as [
-      number,
-      number,
-      unknown,
-      Array<[number, string, unknown]>,
-      number
-    ]
-    return {
-      generation,
-      timestamp,
-      delta,
-      records: rawRecords.map(([kindByte, id, record]) => ({
-        kind: kindByte === 0 ? ('noun' as const) : ('verb' as const),
-        id,
-        record
-      }))
-    }
-  }
-
-  private async readAllFrames(meta: SegmentMeta): Promise<
-    Array<ReturnType<GenerationSegmentStore['decodeFrame']> & { offset: number; frameLen: number }>
-  > {
-    const bytes = await this.storage.readRawBytes(`${SEGMENTS_PREFIX}/${meta.file}`)
-    if (!bytes) {
-      throw new Error(
-        `[GenerationSegments] sealed segment ${meta.file} is MISSING — packed history is damaged; ` +
-          `refusing to continue silently`
-      )
-    }
-    const out: Array<ReturnType<GenerationSegmentStore['decodeFrame']> & { offset: number; frameLen: number }> = []
-    let at = MAGIC.length
-    const view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength)
-    while (at + FRAME_PREFIX_BYTES <= bytes.length) {
-      const payloadLen = view.getUint32(at, true)
-      const crc = view.getUint32(at + 4, true)
-      const payload = bytes.subarray(at + FRAME_PREFIX_BYTES, at + FRAME_PREFIX_BYTES + payloadLen)
-      if (payload.length !== payloadLen || crc32c(payload) !== crc) {
-        throw new Error(
-          `[GenerationSegments] frame CRC mismatch in ${meta.file} at offset ${at} — ` +
-            `packed history is damaged; refusing to serve it`
-        )
-      }
-      out.push({ ...this.decodeFrame(payload), offset: at, frameLen: FRAME_PREFIX_BYTES + payloadLen })
-      at += FRAME_PREFIX_BYTES + payloadLen
-    }
-    return out
-  }
-
-  /** Read one packed generation's frame via its sidecar offset (one ranged read). */
-  private async readFrame(
-    gen: number
-  ): Promise<ReturnType<GenerationSegmentStore['decodeFrame']> | null> {
-    const meta = this.coveringSegment(gen)
-    if (!meta) return null
-    const idx = await this.sidecarFor(meta)
-    // generations ascending → binary search.
-    const gens = idx.generations
-    let lo = 0
-    let hi = gens.length - 1
-    while (lo <= hi) {
-      const mid = (lo + hi) >> 1
-      if (gens[mid][0] < gen) lo = mid + 1
-      else if (gens[mid][0] > gen) hi = mid - 1
-      else {
-        const [, offset, frameLen] = gens[mid]
-        const bytes = await this.storage.readRawBytes(`${SEGMENTS_PREFIX}/${meta.file}`)
-        if (!bytes) {
-          throw new Error(`[GenerationSegments] sealed segment ${meta.file} is MISSING`)
-        }
-        const frame = bytes.subarray(offset, offset + frameLen)
-        const view = new DataView(frame.buffer, frame.byteOffset, frame.byteLength)
-        const payloadLen = view.getUint32(0, true)
-        const crc = view.getUint32(4, true)
-        const payload = frame.subarray(FRAME_PREFIX_BYTES, FRAME_PREFIX_BYTES + payloadLen)
-        if (payload.length !== payloadLen || crc32c(payload) !== crc) {
-          throw new Error(
-            `[GenerationSegments] frame CRC mismatch for generation ${gen} in ${meta.file} — ` +
-              `packed history is damaged; refusing to serve it`
-          )
-        }
-        return this.decodeFrame(payload)
-      }
-    }
-    // In the covering range but not present: the packed tier is dense by
-    // construction (fold packs every generation it is handed, including
-    // record-less ones) — absence inside a sealed range is damage.
-    throw new Error(
-      `[GenerationSegments] generation ${gen} is inside sealed segment ${meta.file}'s declared ` +
-        `range but has no frame — packed history is damaged`
-    )
-  }
-
-  /** The packed tier's delta for `gen` (null = not packed). */
-  async readDelta(gen: number): Promise<{ delta: unknown; timestamp: number } | null> {
-    const frame = await this.readFrame(gen)
-    return frame ? { delta: frame.delta, timestamp: frame.timestamp } : null
-  }
-
-  /** The packed tier's full record-set for `gen` (null = not packed). */
-  async readRecords(gen: number): Promise<FoldGeneration['records'] | null> {
-    const frame = await this.readFrame(gen)
-    return frame ? frame.records : null
-  }
-
-  /** One packed before-image (null = not packed OR no record for the id in that generation). */
-  async readRecord(gen: number, kind: 'noun' | 'verb', id: string): Promise<unknown | null> {
-    const frame = await this.readFrame(gen)
-    if (!frame) return null
-    const hit = frame.records.find((r) => r.kind === kind && r.id === id)
-    return hit ? hit.record : null
-  }
-
-  /**
-   * D3 reclaim: drop WHOLE segments whose lastGeneration < `belowGeneration`
-   * and bump `compactedBelow`. Partial segments are never dropped — the
-   * boundary waits. NEVER called under the archival profile (the caller
-   * enforces retention semantics; this method only executes boundary drops).
-   */
-  async dropSegmentsBelow(belowGeneration: number): Promise<{ dropped: number; compactedBelow: number }> {
-    const keep: SegmentMeta[] = []
-    const drop: SegmentMeta[] = []
-    for (const s of this.manifest.segments) {
-      ;(s.lastGeneration < belowGeneration ? drop : keep).push(s)
-    }
-    if (drop.length === 0) {
-      return { dropped: 0, compactedBelow: this.manifest.compactedBelow }
-    }
-    const compactedBelow = Math.max(
-      this.manifest.compactedBelow,
-      drop[drop.length - 1].lastGeneration + 1
-    )
-    // Manifest first (the drop is authoritative once named), then bytes —
-    // a crash between leaves orphan segment files invisible to the manifest,
-    // harmless and re-collectable.
-    const next: SegmentManifest = { ...this.manifest, compactedBelow, segments: keep }
-    await this.storage.writeRawObject(MANIFEST_PATH, next)
-    await this.storage.syncRawObjects([MANIFEST_PATH])
-    this.manifest = next
-    for (const s of drop) {
-      await this.storage.deleteRawObject(`${SEGMENTS_PREFIX}/${s.file}`)
-      await this.storage.deleteRawObject(`${SEGMENTS_PREFIX}/${sidecarFileName(s.firstGeneration)}`)
-      this.sidecars.delete(s.file)
-    }
-    return { dropped: drop.length, compactedBelow }
-  }
-
-  /**
-   * D8 rider — the packed portion of `generationDigest(g)`: a deterministic
-   * crc32c chain over sealed-segment checksums fully below `g`, plus the
-   * frame CRC of `g`'s own frame when `g` is mid-segment. O(segments), not
-   * O(generations); identical history ⇒ identical digest on any machine.
-   * The live-tier portion is composed by the caller.
-   */
-  async digestThroughPacked(g: number): Promise<number | null> {
-    let digest = 0
-    let covered = false
-    for (const s of this.manifest.segments) {
-      if (s.lastGeneration <= g) {
-        digest = crc32c(new TextEncoder().encode(`${digest}:${s.checksum}`))
-        if (s.lastGeneration === g) covered = true
-      } else if (s.firstGeneration <= g) {
-        // g is mid-segment: chain the partial prefix via g's frame CRC.
-        const frame = await this.readFrame(g)
-        if (frame === null) return null
-        const idx = await this.sidecarFor(s)
-        const upTo = idx.generations.filter(([gen]) => gen <= g)
-        for (const [gen, offset, frameLen] of upTo) {
-          digest = crc32c(new TextEncoder().encode(`${digest}:${gen}:${offset}:${frameLen}`))
-        }
-        covered = true
-        break
-      }
-    }
-    return covered || this.manifest.segments.length > 0 ? digest : null
-  }
-}
--- a/src/db/generationStore.ts
+++ b/src/db/generationStore.ts
@ -46,8 +46,6 @@ import type {
  TxLogEntry
 } from './types.js'
 import { FactLog, storageSupportsFactLog, type CommitFact, type FactOp } from './factLog.js'
-import { GenerationSegmentStore, type FoldGeneration } from './generationSegments.js'
-import { crc32c } from '../utils/crc32c.js'

 /**
 * The byte-identical before-images of every id a commit touches, read UNDER
@ -268,21 +266,6 @@ export class GenerationStore {
   */
  private historyBytesTotal: number | null = null

-  /**
-   * The packed tier (D1+D3): sealed segments holding folded cold
-   * generations. Null until {@link open} wires it (and on storage adapters
-   * without raw-byte primitives — the live tier then carries everything,
-   * exactly as before the packed tier existed).
-   */
-  private segments: GenerationSegmentStore | null = null
-
-  /**
-   * Live-tier window: generations newer than `committed - REPACK_LIVE_WINDOW`
-   * are never folded — the hot tail stays in the per-generation layout the
-   * write path owns. Matches the resident chain window's scale.
-   */
-  static readonly REPACK_LIVE_WINDOW = 1024
-
  /**
   * Model-B per-write group-commit — the in-memory PENDING tier.
   *
@ -450,33 +433,6 @@ export class GenerationStore {
      this.factLog = null
    }

-    // PACKED TIER (D1+D3): same capability gate as the fact log. Opening
-    // reads ONE manifest — never a listing of the packed backlog — and seeds
-    // committedRanges with the sealed ranges so packed generations resolve
-    // exactly like live ones.
-    if (storageSupportsFactLog(this.storage)) {
-      this.segments = new GenerationSegmentStore(this.storage)
-      await this.segments.open()
-      const packedRanges = this.segments
-        .segments()
-        .map((s): [number, number] => [s.firstGeneration, Math.min(s.lastGeneration, this.committed)])
-        .filter(([lo, hi]) => lo <= hi)
-      if (packedRanges.length > 0) {
-        // Merge packed (older) + live (newer) interval sets — both ascending;
-        // coalesce adjacency so range arithmetic stays interval-exact.
-        const merged: Array<[number, number]> = []
-        for (const r of [...packedRanges, ...this.committedRanges].sort((a, b) => a[0] - b[0])) {
-          const last = merged[merged.length - 1]
-          if (last && r[0] <= last[1] + 1) last[1] = Math.max(last[1], r[1])
-          else merged.push([r[0], r[1]])
-        }
-        this.committedRanges = merged
-      }
-      this.horizonGen = Math.max(this.horizonGen, this.segments.compactedBelow() - 1)
-    } else {
-      this.segments = null
-    }
-
    // Hook single-op write batches so generation() is always meaningful.
    // Suppressed while a transact batch executes (the batch is ONE generation).
    if (!options?.readOnly) {
@ -544,51 +500,6 @@ export class GenerationStore {
   * deltas (cache-bounded reads).
   * @returns Counts, bytes, generation range, and the compaction horizon.
   */
-  /**
-   * @description D8 (gate-to-generation provenance): a deterministic content
-   * digest of the generation log THROUGH `g` — identical history ⇒ identical
-   * digest on any machine; any divergence (different records, different
-   * order, reclaimed range) ⇒ different digest. Composed from the packed
-   * tier's sealed-segment checksum chain (O(segments)) plus the live tier's
-   * per-generation delta digests (O(live window at most)). Release gates pin
-   * {generation, digest} and verify both at execution time.
-   * @param g - The generation to digest through (≤ committed).
-   * @returns A hex digest string, stable across reopen and repacking states
-   *   ONLY for fully-packed prefixes — repacking changes representation, so
-   *   the composed digest is defined over CONTENT: live-tier gens hash their
-   *   delta + record ids, packed gens hash via frame CRCs. A gate should pin
-   *   after a repack pass for long-term stability, or re-pin on repack.
-   */
-  async generationDigest(g: number): Promise<string> {
-    if (!Number.isInteger(g) || g < 1 || g > this.committed) {
-      throw new RangeError(
-        `generationDigest(): generation ${g} is out of range [1, ${this.committed}]`
-      )
-    }
-    if (g <= this.horizonGen) {
-      throw new GenerationCompactedError(g, this.horizonGen)
-    }
-    let digest = 0
-    const enc = new TextEncoder()
-    if (this.segments) {
-      const packed = await this.segments.digestThroughPacked(g)
-      if (packed !== null) digest = packed
-    }
-    // Live-tier composition: every committed gen ≤ g not covered by a sealed
-    // segment hashes its delta content in ascending order.
-    for (const gen of this.committedGensAsc()) {
-      if (gen > g) break
-      if (this.segments?.hasGeneration(gen)) continue
-      const delta = await this.getDelta(gen)
-      digest = crc32c(
-        enc.encode(
-          `${digest}:${gen}:${delta.timestamp}:${[...delta.nouns].sort().join(',')}:${[...delta.verbs].sort().join(',')}`
-        )
-      )
-    }
-    return digest.toString(16).padStart(8, '0')
-  }
-
  async historyStats(): Promise<{
    generations: number
    bytes: number
@ -627,17 +538,14 @@ export class GenerationStore {
    try {
      paths = await this.storage.listRawObjects(`${GENERATIONS_PREFIX}/${gen}/prev`)
    } catch {
-      paths = []
+      return []
    }
    const records: GenerationRecord[] = []
    for (const p of paths) {
      const record = (await this.storage.readRawObject(p)) as GenerationRecord | null
      if (record) records.push(record)
    }
-    if (records.length > 0) return records
-    // Two-tier: folded generations serve their record-set from the segment.
-    const packed = await this.segments?.readRecords(gen)
-    return packed ? (packed.map((r) => r.record) as GenerationRecord[]) : []
+    return records
  }

  /**
@ -1875,15 +1783,9 @@ export class GenerationStore {
    if (pending) {
      return (kind === 'noun' ? pending.nouns : pending.verbs).get(id) ?? null
    }
-    const live = (await this.storage.readRawObject(
+    return (await this.storage.readRawObject(
      `${GENERATIONS_PREFIX}/${gen}/prev/${id}.json`
    )) as GenerationRecord | null
-    if (live) return live
-    // Two-tier: the packed tier serves folded generations (live-tier-wins).
-    if (this.segments?.hasGeneration(gen)) {
-      return (await this.segments.readRecord(gen, kind, id)) as GenerationRecord | null
-    }
-    return null
  }

  /**
@ -2230,21 +2132,6 @@ export class GenerationStore {
      `${GENERATIONS_PREFIX}/${gen}/tx.json`
    )) as GenerationDelta | null
    if (delta === null) {
-      // Two-tier read (D1+D3): not in the live tier → the packed tier.
-      // Live-tier-wins ordering (a crash mid-fold leaves a duplicate, never
-      // a gap), so the segment lookup runs only after the live miss.
-      const packed = await this.segments?.readDelta(gen)
-      if (packed) {
-        const d = packed.delta as GenerationDelta
-        const entry = {
-          nouns: new Set(d.nouns),
-          verbs: new Set(d.verbs),
-          timestamp: packed.timestamp,
-          bytes: d.bytes ?? 0
-        }
-        this.setDelta(gen, entry)
-        return entry
-      }
      throw new Error(
        `Generation delta missing: ${GENERATIONS_PREFIX}/${gen}/tx.json ` +
          `(store corrupted or records removed outside compactHistory())`
@ -2326,94 +2213,6 @@ export class GenerationStore {
   * @param options - Retention caps (see {@link CompactHistoryOptions}).
   * @returns Count of removed record-sets and the new horizon.
   */
-  /**
-   * @description The REPACKER (D1+D3+repacking): fold cold live-tier
-   * generations into sealed segments — re-representation, never deletion.
-   * Every record and delta stays readable (asOf/chains unchanged); the
-   * per-generation directories are deleted only AFTER their segment is
-   * durable (crash between = duplicate representation, resolved
-   * live-tier-wins by every reader; never a gap). This is the transform that
-   * takes a 70k-file history to tens of segment files, and the ONLY history
-   * transform permitted under the archival profile.
-   *
-   * Folds oldest-first, contiguous from the packed boundary, in batches, and
-   * stops at the live window ({@link GenerationStore.REPACK_LIVE_WINDOW})
-   * or when `timeBudgetMs` is spent — an early stop is a consistent prefix;
-   * the next pass resumes.
-   */
-  async repackHistory(options?: { timeBudgetMs?: number; batchGenerations?: number }): Promise<{
-    foldedGenerations: number
-    segmentsCreated: number
-  }> {
-    if (!this.segments) return { foldedGenerations: 0, segmentsCreated: 0 }
-    const segments = this.segments
-    return this.withMutex(async () => {
-      const deadline =
-        options?.timeBudgetMs !== undefined ? Date.now() + options.timeBudgetMs : undefined
-      const batchSize = options?.batchGenerations ?? 512
-      const coldCeiling = this.committed - GenerationStore.REPACK_LIVE_WINDOW
-      const packedThrough =
-        segments.segments().length > 0
-          ? segments.segments()[segments.segments().length - 1].lastGeneration
-          : 0
-
-      // Cold, unpacked, committed generations — ascending, contiguous scan.
-      const eligible: number[] = []
-      for (const gen of this.committedGensAsc()) {
-        if (gen > coldCeiling) break
-        if (gen <= packedThrough) continue // already packed (dup fold barred)
-        if (this.pendingBuffer.has(gen)) continue // un-flushed = live by definition
-        eligible.push(gen)
-      }
-
-      let folded = 0
-      let segmentsCreated = 0
-      for (let i = 0; i < eligible.length; i += batchSize) {
-        if (deadline !== undefined && Date.now() >= deadline) break
-        const batch = eligible.slice(i, i + batchSize)
-        const foldInput: FoldGeneration[] = []
-        for (const gen of batch) {
-          const delta = (await this.storage.readRawObject(
-            `${GENERATIONS_PREFIX}/${gen}/tx.json`
-          )) as GenerationDelta | null
-          if (delta === null) {
-            // Already folded by a prior crashed pass whose dirs were removed,
-            // or damage — getDelta's two-tier read decides which, loudly,
-            // when someone asks. Skip; never fold a generation we cannot read.
-            continue
-          }
-          const records: FoldGeneration['records'] = []
-          for (const [kind, ids] of [
-            ['noun', delta.nouns] as const,
-            ['verb', delta.verbs] as const
-          ]) {
-            for (const id of ids) {
-              const record = await this.storage.readRawObject(
-                `${GENERATIONS_PREFIX}/${gen}/prev/${id}.json`
-              )
-              if (record) records.push({ kind, id, record })
-            }
-          }
-          foldInput.push({ generation: gen, timestamp: delta.timestamp, delta, records })
-        }
-        if (foldInput.length === 0) continue
-        await segments.fold(foldInput)
-        segmentsCreated++
-        // Segment + manifest durable → the live copies retire.
-        for (const g of foldInput) {
-          await this.storage.removeRawPrefix(`${GENERATIONS_PREFIX}/${g.generation}`)
-        }
-        folded += foldInput.length
-      }
-      if (folded > 0) {
-        prodLog.info(
-          `[GenerationStore] repacked ${folded} cold generation(s) into ${segmentsCreated} segment(s) — history preserved, file count reduced`
-        )
-      }
-      return { foldedGenerations: folded, segmentsCreated }
-    })
-  }
-
  async compact(options?: CompactHistoryOptions): Promise<CompactHistoryResult> {
    return this.withMutex(async () => {
      const minPinned = this.minPinnedGeneration()
@ -2421,11 +2220,6 @@ export class GenerationStore {
      const maxAge = options?.maxAge
      const maxBytes = options?.maxBytes
      const ageCutoff = maxAge !== undefined ? Date.now() - maxAge : undefined
-      // Bounded maintenance pass (8.9.0): stop reclaiming once the budget is
-      // spent. Safe mid-loop — reclamation is oldest-first, so an early stop
-      // leaves a consistent contiguous prefix and the next pass resumes.
-      const deadline =
-        options?.timeBudgetMs !== undefined ? Date.now() + options.timeBudgetMs : undefined
      const noCaps =
        maxGenerations === undefined && maxAge === undefined && maxBytes === undefined

@ -2439,7 +2233,6 @@ export class GenerationStore {
      for (const gen of [...this.committedGensAsc()]) {
        // Pins are always exempt: never reclaim a generation a live pin needs.
        if (gen > minPinned) break // committedGensAsc ascending → nothing newer is eligible either
-        if (deadline !== undefined && Date.now() >= deadline) break // budget spent — resume next pass
        const delta = await this.getDelta(gen)
        if (!noCaps) {
          const violatesCount = maxGenerations !== undefined && remainingCount > maxGenerations
@ -2505,16 +2298,6 @@ export class GenerationStore {
        // Reclaimed generations leave the per-id chains stale → rebuild on next read.
        this.invalidateChains()
        this.horizonGen = Math.max(this.horizonGen, highestRemoved)
-        // Packed-tier reclaim (D3): a packed generation's bytes live in a
-        // sealed segment — removeRawPrefix above was a no-op for it. Drop
-        // WHOLE segments now fully below the horizon; a partially-reclaimed
-        // segment keeps its bytes until the boundary passes it (the frozen
-        // partial-segments-wait rule; logical reclamation above still holds —
-        // the generations left committedRanges and asOf below the horizon
-        // throws regardless).
-        if (this.segments) {
-          await this.segments.dropSegmentsBelow(this.horizonGen + 1)
-        }
        const manifest: GenerationManifest = {
          version: 1,
          generation: this.committed,
--- a/src/db/types.ts
+++ b/src/db/types.ts
@ -176,15 +176,6 @@ export interface CompactHistoryOptions {
   * of each surviving generation's serialized record set (`GenerationDelta.bytes`).
   */
  maxBytes?: number
-  /**
-   * Stop reclaiming after this many milliseconds even if caps are still
-   * exceeded (8.9.0). Compaction is maintenance — a bounded pass keeps
-   * `close()` (and any explicit maintenance window) from stalling on a large
-   * backlog; the next pass resumes where this one stopped (reclamation is
-   * oldest-first, so an early stop is always a consistent prefix). Unset =
-   * run to completion.
-   */
-  timeBudgetMs?: number
 }

 /**
--- a/src/index.ts
+++ b/src/index.ts
@ -213,7 +213,6 @@ export type {
  CommitFact,
  FactOp,
  FactScanBatch,
-  SCANFACTS_FIRST_BATCH_MS,
  FactScanHandle
 } from './db/factLog.js'
 // The generalized family stamp — which source generation a projection
--- a/src/storage/adapters/fileSystemStorage.ts
+++ b/src/storage/adapters/fileSystemStorage.ts
@ -96,14 +96,6 @@ export class FileSystemStorage extends BaseStorage {
  private static readonly WRITER_STALE_THRESHOLD_MS = 60_000
  private writerLockHeartbeat?: NodeJS.Timeout
  private writerLockInfo?: WriterLockInfo
-  /**
-   * The currently-executing heartbeat refresh, if any. `releaseWriterLock()`
-   * awaits it before unlinking: clearInterval() stops FUTURE ticks but not a
-   * tick already in flight, and a straggler landing after the unlink would
-   * RE-CREATE the lock file — a phantom lock blocking the next writer until
-   * the stale TTL expires (the pool-eviction reopen case).
-   */
-  private writerHeartbeatInFlight?: Promise<void>

  // Flush-request RPC state. The writer polls `locks/_flush_requests/` for
  // new `.req` files and emits `.ack` files in `locks/_flush_responses/` after
@ -1888,18 +1880,8 @@ export class FileSystemStorage extends BaseStorage {
    // Heartbeat — rewrite lastHeartbeat every WRITER_HEARTBEAT_MS so other
    // processes can tell a live writer from one that crashed without releasing.
    this.writerLockHeartbeat = setInterval(() => {
-      const tick = this.refreshWriterLockHeartbeat().catch((err) => {
-        // ENOENT = the lock (or its directory) vanished mid-refresh — the
-        // store was released or removed under us; the next acquire recreates
-        // it. Benign by construction; anything else stays loud.
-        if ((err as NodeJS.ErrnoException)?.code !== 'ENOENT') {
-          console.warn('[brainy] Failed to refresh writer lock heartbeat:', err)
-        }
-      })
-      this.writerHeartbeatInFlight = tick.finally(() => {
-        if (this.writerHeartbeatInFlight === tick) {
-          this.writerHeartbeatInFlight = undefined
-        }
+      this.refreshWriterLockHeartbeat().catch((err) => {
+        console.warn('[brainy] Failed to refresh writer lock heartbeat:', err)
      })
    }, FileSystemStorage.WRITER_HEARTBEAT_MS)
    if (typeof this.writerLockHeartbeat.unref === 'function') {
@ -1931,15 +1913,6 @@ export class FileSystemStorage extends BaseStorage {
      clearInterval(this.writerLockHeartbeat)
      this.writerLockHeartbeat = undefined
    }
-    // Drain an in-flight heartbeat tick BEFORE unlinking: clearInterval stops
-    // future ticks only, and a straggler write landing after the unlink would
-    // re-create the lock as a phantom (blocking the next writer until the
-    // stale TTL). After the drain, any refresh is either fully landed (we
-    // unlink its output below) or not started (it sees writerLockInfo
-    // undefined and returns).
-    if (this.writerHeartbeatInFlight) {
-      await this.writerHeartbeatInFlight
-    }
    if (!this.writerLockInfo) {
      return
    }
--- a/src/storage/adapters/memoryStorage.ts
+++ b/src/storage/adapters/memoryStorage.ts
@ -133,11 +133,6 @@ export class MemoryStorage extends BaseStorage {
   */
  protected async deleteObjectFromPath(path: string): Promise<void> {
    this.objectStore.delete(path)
-    // Filesystem parity: on disk, objects and raw BYTE files are both just
-    // files — unlink removes whichever exists. Without this, deleteRawObject
-    // on a raw-bytes path (fact-log/generation segments) silently no-ops on
-    // memory storage: the delete "succeeds" and the bytes remain.
-    this.rawBytesStore.delete(path)
  }

  /**
--- a/src/types/brainy.types.ts
+++ b/src/types/brainy.types.ts
@ -1737,10 +1737,7 @@ export interface BrainyConfig {
   * Under Model-B EVERY write (`transact()` AND single-op `add`/`update`/
   * `remove`/`relate`) produces an immutable generation record-set serving
   * historical reads (`asOf()`, pinned `Db` values). Without compaction those
-   * accumulate, so Brainy **auto-compacts at `close()`** (time-bounded per
-   * pass; 8.9.0 removed compaction from `flush()` — flush is durability work
-   * and never pays maintenance costs). A long-lived writer that never closes
-   * accumulates history until its next explicit `compactHistory()` call.
+   * accumulate, so Brainy **auto-compacts on every `flush()` and `close()`**.
   * Live `Db` pins are ALWAYS exempt from reclamation, in every mode.
   *
   * Modes:
@ -1757,7 +1754,7 @@ export interface BrainyConfig {
   *   the oldest unpinned generations while ANY supplied cap is exceeded
   *   (predictable ops). `maxAge` in ms; `maxBytes` total history bytes.
   *
-   * `autoCompact: false` disables the automatic close() compaction (manage
+   * `autoCompact: false` disables the automatic flush/close compaction (manage
   * manually via `brain.compactHistory()`). `budgetBytes` is the settable
   * adaptive byte budget a coordinator drives (also via `brain.setRetentionBudget()`).
   * Long-term archives belong in `db.persist(path)` snapshots, which compaction
@ -1775,7 +1772,7 @@ export interface BrainyConfig {
        maxBytes?: number
        /** Adaptive byte budget for this brain, driven by a coordinator (e.g. cor). */
        budgetBytes?: number
-        /** Run compaction automatically at close() (default: true; 8.9.0 — flush() never compacts). */
+        /** Run compaction automatically on flush()/close() (default: true). */
        autoCompact?: boolean
      }

--- a/src/utils/metadataIndex.ts
+++ b/src/utils/metadataIndex.ts
@ -1867,26 +1867,9 @@ export class MetadataIndexManager implements MetadataIndexProvider {
    // not once per AND-clause inside it.
    const unindexedFields: string[] = []

-    for (const [rawField, condition] of Object.entries(filter)) {
+    for (const [field, condition] of Object.entries(filter)) {
      // Skip logical operators
-      if (rawField === 'allOf' || rawField === 'anyOf' || rawField === 'not') continue
-
-      // Metadata is FLATTENED at index time (metadata.entry.title indexes as
-      // entry.title), so a `metadata.`-prefixed where key is almost always
-      // the caller spelling the STORAGE shape rather than the index shape.
-      // Accept both spellings: when the key as spelled is unindexed but its
-      // stripped spelling is, query the stripped one. A literal nested
-      // custom key named `metadata` still wins when indexed as spelled
-      // (checked first), so that rare shape keeps working.
-      let field = rawField
-      if (
-        rawField.startsWith('metadata.') &&
-        this.columnStore &&
-        !this.columnStore.hasField(rawField) &&
-        this.columnStore.hasField(rawField.slice('metadata.'.length))
-      ) {
-        field = rawField.slice('metadata.'.length)
-      }
+      if (field === 'allOf' || field === 'anyOf' || field === 'not') continue

      let fieldResults: string[] = []

--- a/tests/integration/aggregate-reserved-fields.test.ts
+++ b/tests/integration/aggregate-reserved-fields.test.ts
@ -1,169 +0,0 @@
-/**
- * @module tests/integration/aggregate-reserved-fields
- * @description One field-resolution law across the whole aggregation + query
- * surface (SELF-AGGREGATE-DELETE-DRIFT). Laws:
- * (1) aggregates grouped by a RESERVED field (subtype) decrement on delete —
- *     the delete-side entity view carries every reserved field, so the
- *     decrement finds its group (counts must never drift from ground truth);
- * (2) same for update: moving an entity between reserved-field groups
- *     decrements the old group and increments the new one (no double-count);
- * (3) aggregation source.where on a reserved field (subtype) FILTERS instead
- *     of silently matching nothing;
- * (4) removeMany refuses empty/invalid selectors loudly (bare array, empty
- *     object, ids: []) instead of resolving as a silent no-op;
- * (5) find() accepts both where spellings: flattened (entry.title) and
- *     storage-shaped (metadata.entry.title) resolve to the same rows.
- */
-import { describe, it, expect, beforeEach, afterEach } from 'vitest'
-import { Brainy } from '../../src/brainy.js'
-import { NounType } from '../../src/types/graphTypes.js'
-
-const stubEmbedding = async (text: string): Promise<number[]> => {
-  const hash = text.split('').reduce((acc, char) => acc + char.charCodeAt(0), 0)
-  return new Array(384).fill(0).map((_, i) => Math.sin(hash + i))
-}
-
-describe('aggregation + query field-resolution law', () => {
-  let brain: Brainy
-
-  beforeEach(async () => {
-    brain = new Brainy({
-      requireSubtype: false,
-      storage: { type: 'memory' as const },
-      embeddingFunction: stubEmbedding
-    })
-    await brain.init()
-  })
-
-  afterEach(async () => {
-    await brain.close()
-  })
-
-  it('reserved-field groupBy decrements on delete (the drift bug)', async () => {
-    brain.defineAggregate({
-      name: 'by_subtype',
-      source: { type: NounType.Document },
-      groupBy: ['subtype'],
-      metrics: { count: { op: 'count' } }
-    })
-
-    const ids: string[] = []
-    for (let i = 0; i < 5; i++) {
-      ids.push(
-        await brain.add({
-          data: `doc-${i}`,
-          type: NounType.Document,
-          subtype: 'note',
-          metadata: { team: 'alpha' }
-        })
-      )
-    }
-    let groups = await brain.queryAggregate('by_subtype')
-    expect(groups).toHaveLength(1)
-    expect(groups[0].groupKey).toEqual({ subtype: 'note' })
-    expect(groups[0].metrics.count).toBe(5)
-
-    await brain.remove(ids[0])
-    await brain.flush()
-
-    groups = await brain.queryAggregate('by_subtype')
-    expect(groups[0].metrics.count).toBe(4)
-    const live = await brain.find({ type: NounType.Document, limit: 100 })
-    expect(groups[0].metrics.count).toBe(live.length)
-  })
-
-  it('reserved-field groupBy moves between groups on update (no double-count)', async () => {
-    brain.defineAggregate({
-      name: 'by_subtype',
-      source: { type: NounType.Document },
-      groupBy: ['subtype'],
-      metrics: { count: { op: 'count' } }
-    })
-    const id = await brain.add({
-      data: 'doc-move',
-      type: NounType.Document,
-      subtype: 'draft'
-    })
-    await brain.update({ id, subtype: 'published' })
-
-    const groups = await brain.queryAggregate('by_subtype')
-    const byKey = Object.fromEntries(
-      groups.map((g) => [String(g.groupKey.subtype), g.metrics.count])
-    )
-    expect(byKey['published']).toBe(1)
-    // The old group must be gone or zero — never still counting the entity.
-    expect(byKey['draft'] ?? 0).toBe(0)
-  })
-
-  it('source.where on a reserved field filters instead of matching nothing', async () => {
-    brain.defineAggregate({
-      name: 'notes_only',
-      source: { type: NounType.Document, where: { subtype: 'note' } },
-      groupBy: ['team'],
-      metrics: { count: { op: 'count' } }
-    })
-    await brain.add({
-      data: 'n1',
-      type: NounType.Document,
-      subtype: 'note',
-      metadata: { team: 'alpha' }
-    })
-    await brain.add({
-      data: 'd1',
-      type: NounType.Document,
-      subtype: 'draft',
-      metadata: { team: 'alpha' }
-    })
-
-    const groups = await brain.queryAggregate('notes_only')
-    expect(groups).toHaveLength(1)
-    expect(groups[0].metrics.count).toBe(1) // the note, never the draft
-  })
-
-  it('removeMany refuses empty/invalid selectors loudly', async () => {
-    const id = await brain.add({ data: 'keep-me', type: NounType.Document })
-
-    // Bare array passed positionally — the classic silent no-op.
-    await expect(
-      brain.removeMany([id] as unknown as Parameters<typeof brain.removeMany>[0])
-    ).rejects.toThrow(/bare array/)
-    // Empty selector object.
-    await expect(
-      brain.removeMany({} as Parameters<typeof brain.removeMany>[0])
-    ).rejects.toThrow(/requires a selector/)
-    // Explicit empty id list.
-    await expect(brain.removeMany({ ids: [] })).rejects.toThrow(/ids: \[\]/)
-
-    // Nothing was deleted by any of the refused calls.
-    expect(await brain.get(id)).toBeTruthy()
-  })
-
-  it('find() accepts both flattened and metadata.-prefixed where spellings', async () => {
-    await brain.add({
-      data: 'nested-doc',
-      type: NounType.Document,
-      metadata: { entry: { title: 'T1' }, classifier: { contextHints: { vfsPath: '/n/a.md' } } }
-    })
-    await brain.flush()
-
-    const flat = await brain.find({
-      type: NounType.Document,
-      where: { 'entry.title': 'T1' },
-      limit: 10
-    })
-    const prefixed = await brain.find({
-      type: NounType.Document,
-      where: { 'metadata.entry.title': 'T1' },
-      limit: 10
-    })
-    const deepPrefixed = await brain.find({
-      type: NounType.Document,
-      where: { 'metadata.classifier.contextHints.vfsPath': '/n/a.md' },
-      limit: 10
-    })
-    expect(flat).toHaveLength(1)
-    expect(prefixed).toHaveLength(1)
-    expect(prefixed[0].id).toBe(flat[0].id)
-    expect(deepPrefixed).toHaveLength(1)
-  })
-})
--- a/tests/integration/db-mvcc.test.ts
+++ b/tests/integration/db-mvcc.test.ts
@ -1280,32 +1280,24 @@ describe('8.0 Db API — generational MVCC', () => {
    await expect(reopened.asOf(1)).rejects.toBeInstanceOf(GenerationCompactedError)
  })

-  it('Model-B retention — flush() NEVER compacts (8.9.0); adaptive reclaim runs at close()', async () => {
-    // Default brain → ADAPTIVE retention with a driven byte budget far below
-    // the accumulated history (~13 generations of full-vector before-images).
-    // The 8.9.0 law: flush() is durability-only — it must not reclaim even
-    // when the budget is exceeded (reclaim-on-flush blocked production writes
-    // for 25-191s). Maintenance runs at close(), time-bounded.
-    const { brain, dir } = await openFsBrain()
+  it('Model-B retention — setRetentionBudget drives adaptive reclaim on flush; live data intact', async () => {
+    // Default brain → ADAPTIVE retention. A coordinator (e.g. cor's ResourceManager)
+    // pushes a byte budget via setRetentionBudget(); auto-compaction on flush() reclaims
+    // oldest history down toward it. Each update's before-image carries the full prior
+    // 384-dim vector (~KBs), so ~13 generations far exceed a few-KB budget.
+    const { brain } = await openFsBrain()
    const a = uid('ret-budget')
    await brain.add({ id: a, type: NounType.Document, data: 'v0', vector: vec(1), metadata: { v: 0 } })
    for (let v = 1; v <= 12; v++) await brain.update({ id: a, metadata: { v } })

    brain.setRetentionBudget(6000) // ~6 KB — well below the accumulated history
-    await brain.flush()
+    await brain.flush() // group-commit + adaptive auto-compaction under the budget

-    // flush() paid durability only: nothing reclaimed, all history readable.
-    expect(generationStoreOf(brain).horizon()).toBe(0)
-    const probe = await brain.asOf(1) // readable proves nothing was reclaimed…
-    await probe.release() // …and MUST be released: a held pin would (correctly)
-    // protect every newer generation through the close() compaction below.
-    await brain.close() // ← THE auto-compaction site now
-
-    // close() reclaimed under the budget; live record intact; horizon durable.
-    const { brain: reopened } = await openFsBrain(dir)
-    expect(generationStoreOf(reopened).horizon()).toBeGreaterThan(0)
-    await expect(reopened.asOf(1)).rejects.toBeInstanceOf(GenerationCompactedError)
-    expect((await reopened.get(a))?.metadata?.v).toBe(12)
+    // History was reclaimed (the horizon advanced past the oldest generations)…
+    expect(generationStoreOf(brain).horizon()).toBeGreaterThan(0)
+    await expect(brain.asOf(1)).rejects.toBeInstanceOf(GenerationCompactedError)
+    // …but the budget reclaims HISTORY only — the live record is untouched.
+    expect((await brain.get(a))?.metadata?.v).toBe(12)
  })

  // ==========================================================================
--- a/tests/integration/history-repacking.test.ts
+++ b/tests/integration/history-repacking.test.ts
@ -1,186 +0,0 @@
-/**
- * @module tests/integration/history-repacking
- * @description The D1+D3 two-tier history lifecycle end-to-end on a real
- * brain. Laws: (1) repacking is RE-REPRESENTATION — after folding, every
- * asOf() read below the fold boundary answers exactly as before, across a
- * cold reopen; (2) folded per-generation directories are physically gone
- * (the file-count cure is real, not cosmetic); (3) repack + reclaim compose:
- * bounded retention after repacking drops whole segments and asOf below the
- * horizon throws GenerationCompactedError; (4) repackHistory is explicit
- * API and time-bounded (spent budget = consistent no-op).
- *
- * Uses a tiny REPACK_LIVE_WINDOW override so a small history has a cold
- * tier at all (the production window is 1024).
- */
-import { describe, it, expect, afterEach } from 'vitest'
-import * as fs from 'node:fs'
-import * as path from 'node:path'
-import * as os from 'node:os'
-import { Brainy } from '../../src/brainy.js'
-import { NounType } from '../../src/types/graphTypes.js'
-import { GenerationStore } from '../../src/db/generationStore.js'
-import { GenerationCompactedError } from '../../src/db/errors.js'
-import { SEGMENTS_PREFIX } from '../../src/db/generationSegments.js'
-
-const stub = async (text: string): Promise<number[]> => {
-  const h = text.split('').reduce((a, c) => a + c.charCodeAt(0), 0)
-  return new Array(384).fill(0).map((_, i) => Math.sin(h + i))
-}
-
-const openBrain = async (dir: string): Promise<Brainy> => {
-  const brain = new Brainy({
-    requireSubtype: false,
-    storage: { type: 'filesystem', path: dir },
-    embeddingFunction: stub
-  })
-  await brain.init()
-  return brain
-}
-
-describe('history repacking — the two-tier lifecycle', () => {
-  const dirs: string[] = []
-  const tempDir = (): string => {
-    const d = fs.mkdtempSync(path.join(os.tmpdir(), 'brainy-repack-'))
-    dirs.push(d)
-    return d
-  }
-  const originalWindow = GenerationStore.REPACK_LIVE_WINDOW
-
-  afterEach(() => {
-    ;(GenerationStore as any).REPACK_LIVE_WINDOW = originalWindow
-    for (const d of dirs.splice(0)) {
-      try {
-        fs.rmSync(d, { recursive: true, force: true })
-      } catch {
-        /* best effort */
-      }
-    }
-  })
-
-  it('repack preserves every historical read across cold reopen; folded dirs are gone', async () => {
-    ;(GenerationStore as any).REPACK_LIVE_WINDOW = 3
-    const dir = tempDir()
-    const brain = await openBrain(dir)
-
-    const id = await brain.add({
-      data: 'versioned-entity',
-      type: NounType.Document,
-      metadata: { v: 0 }
-    })
-    for (let v = 1; v <= 10; v++) await brain.update({ id, metadata: { v } })
-    await brain.flush()
-
-    // Ground truth BEFORE repacking: capture asOf views for early generations.
-    const before: Record<number, number> = {}
-    for (const g of [2, 4, 6]) {
-      const db = await brain.asOf(g)
-      before[g] = (await db.get(id))?.metadata?.v as number
-      await db.release()
-    }
-
-    const result = await brain.repackHistory()
-    expect(result.foldedGenerations).toBeGreaterThan(0)
-    expect(result.segmentsCreated).toBeGreaterThan(0)
-
-    // The folded per-generation directories are PHYSICALLY gone…
-    const genDirs = fs
-      .readdirSync(path.join(dir, '_generations'), { withFileTypes: true })
-      .filter((e) => e.isDirectory() && /^\d+$/.test(e.name)).length
-    expect(genDirs).toBeLessThanOrEqual(4) // live window (3) + at most the newest
-    // …and the segment tier exists (the filesystem adapter stores objects
-    // gzipped, so the manifest may live at either spelling).
-    const segDir = path.join(dir, SEGMENTS_PREFIX)
-    expect(
-      fs.existsSync(path.join(segDir, 'manifest.json')) ||
-        fs.existsSync(path.join(segDir, 'manifest.json.gz'))
-    ).toBe(true)
-    expect(fs.readdirSync(segDir).some((f) => f.endsWith('.bgs'))).toBe(true)
-
-    // Same asOf answers from the packed tier, same process…
-    for (const g of [2, 4, 6]) {
-      const db = await brain.asOf(g)
-      expect((await db.get(id))?.metadata?.v).toBe(before[g])
-      await db.release()
-    }
-    await brain.close()
-
-    // …and across a COLD REOPEN (manifest discovery, no live dirs to list).
-    const reopened = await openBrain(dir)
-    for (const g of [2, 4, 6]) {
-      const db = await reopened.asOf(g)
-      expect((await db.get(id))?.metadata?.v).toBe(before[g])
-      await db.release()
-    }
-    expect((await reopened.get(id))?.metadata?.v).toBe(10) // live state untouched
-    await reopened.close()
-  })
-
-  it('repack + bounded reclaim compose: whole segments drop, horizon is loud', async () => {
-    ;(GenerationStore as any).REPACK_LIVE_WINDOW = 2
-    const dir = tempDir()
-    const brain = await openBrain(dir)
-    const id = await brain.add({ data: 'reclaim-probe', type: NounType.Document, metadata: { v: 0 } })
-    for (let v = 1; v <= 8; v++) await brain.update({ id, metadata: { v } })
-    await brain.flush()
-    await brain.repackHistory()
-
-    // Reclaim down to the 3 newest generations — packed segments below the
-    // horizon drop whole; asOf below throws loudly.
-    const res = await brain.compactHistory({ maxGenerations: 3 })
-    expect(res.removedGenerations).toBeGreaterThan(0)
-    await expect(brain.asOf(1)).rejects.toBeInstanceOf(GenerationCompactedError)
-    expect((await brain.get(id))?.metadata?.v).toBe(8)
-    await brain.close()
-  })
-
-  it('generationDigest: reopen-stable, divergence-sensitive, loud below the horizon', async () => {
-    ;(GenerationStore as any).REPACK_LIVE_WINDOW = 2
-    const dir = tempDir()
-    const brain = await openBrain(dir)
-    const id = await brain.add({ data: 'digest-probe', type: NounType.Document, metadata: { v: 0 } })
-    for (let v = 1; v <= 6; v++) await brain.update({ id, metadata: { v } })
-    await brain.flush()
-    await brain.repackHistory()
-
-    const gen = brain.generation()
-    const atHead = await brain.generationDigest(gen)
-    const atMid = await brain.generationDigest(3)
-    expect(atHead).toMatch(/^[0-9a-f]{8}$/)
-    expect(atMid).not.toBe(atHead) // more history ⇒ different digest
-    await brain.close()
-
-    // Reopen-stable: same history, same digests (packed prefix stability).
-    const reopened = await openBrain(dir)
-    expect(await reopened.generationDigest(gen)).toBe(atHead)
-    expect(await reopened.generationDigest(3)).toBe(atMid)
-
-    // New history diverges the head digest.
-    await reopened.update({ id, metadata: { v: 7 } })
-    await reopened.flush()
-    expect(await reopened.generationDigest(reopened.generation())).not.toBe(atHead)
-
-    // Below the horizon: LOUD, never a silent pin of reclaimed history.
-    await reopened.compactHistory({ maxGenerations: 2 })
-    await expect(reopened.generationDigest(1)).rejects.toBeInstanceOf(GenerationCompactedError)
-    await reopened.close()
-  })
-
-  it('a spent time budget is a consistent no-op; the next pass resumes', async () => {
-    ;(GenerationStore as any).REPACK_LIVE_WINDOW = 2
-    const dir = tempDir()
-    const brain = await openBrain(dir)
-    const id = await brain.add({ data: 'budget-probe', type: NounType.Document, metadata: { v: 0 } })
-    for (let v = 1; v <= 6; v++) await brain.update({ id, metadata: { v } })
-    await brain.flush()
-
-    const bounded = await brain.repackHistory({ timeBudgetMs: 0 })
-    expect(bounded).toEqual({ foldedGenerations: 0, segmentsCreated: 0 })
-
-    const resumed = await brain.repackHistory()
-    expect(resumed.foldedGenerations).toBeGreaterThan(0)
-    const db = await brain.asOf(3)
-    expect((await db.get(id))?.metadata?.v).toBeDefined()
-    await db.release()
-    await brain.close()
-  })
-})
--- a/tests/integration/multi-process-safety.test.ts
+++ b/tests/integration/multi-process-safety.test.ts
@ -153,46 +153,6 @@ describe('Multi-process safety + read-only mode', () => {
      expect(err.lockInfo?.pid).toBe(otherPid)
    })

-    it('release drains an in-flight heartbeat — no phantom lock re-created after unlink', async () => {
-      // The race (8.9.0): clearInterval stops FUTURE heartbeat ticks, but a
-      // tick already in flight could land its lock rewrite AFTER release's
-      // unlink — re-creating the lock as a phantom that blocks the next
-      // writer until the stale TTL. Simulate the in-flight tick explicitly
-      // and prove release waits for it.
-      writer = new Brainy({ requireSubtype: false, storage: { type: 'filesystem', path: dir } })
-      await writer.init()
-      const storage: any = (writer as any).storage
-
-      // An in-flight refresh that is ALREADY PAST its ownership guards
-      // (captured the lock info before release ran) and lands its atomic
-      // rewrite slowly — the exact straggler shape; absent the drain it
-      // writes after the unlink.
-      const { join: joinPath } = await import('node:path')
-      const capturedInfo = { ...storage.writerLockInfo }
-      const lockPath = joinPath(dir, 'locks', '_writer.lock')
-      const slowTick = (async () => {
-        await new Promise((r) => setTimeout(r, 100))
-        await storage.writeFileAtomic(
-          lockPath,
-          JSON.stringify({ ...capturedInfo, lastHeartbeat: new Date().toISOString() })
-        )
-      })()
-      storage.writerHeartbeatInFlight = slowTick.catch(() => {})
-
-      await writer.close() // → releaseWriterLock must drain slowTick first
-      await slowTick.catch(() => {}) // both paths fully settled either way
-      writer = null
-
-      const { existsSync } = await import('node:fs')
-      const { join } = await import('node:path')
-      expect(existsSync(join(dir, 'locks', '_writer.lock'))).toBe(false)
-
-      // And the directory is immediately claimable — no stale-TTL wait.
-      const next = new Brainy({ requireSubtype: false, storage: { type: 'filesystem', path: dir } })
-      await expect(next.init()).resolves.toBeUndefined()
-      await next.close()
-    })
-
    it('allows a second in-process writer with a warning (same PID)', async () => {
      // Two Brainy instances in the same Node process: not the dangerous
      // cross-process case. Should succeed (with a console warning).
--- a/tests/regression/metadata-index-cleanup.unit.test.ts
+++ b/tests/regression/metadata-index-cleanup.unit.test.ts
@ -205,10 +205,10 @@ describe('Metadata index cleanup after remove / removeMany', () => {
      }
    })

-    it('refuses an empty ids array loudly (a silent no-op is not "graceful")', async () => {
-      // 8.8.2: an empty selector used to resolve successfully having deleted
-      // NOTHING — the caller believed the delete happened. Now it throws.
-      await expect(brain.removeMany({ ids: [] })).rejects.toThrow(/ids: \[\]/)
+    it('handles empty ids array gracefully', async () => {
+      const result = await brain.removeMany({ ids: [] })
+      expect(result.successful).toHaveLength(0)
+      expect(result.failed).toHaveLength(0)
    })

    it('handles large batch (> 1 chunk) without leaving stale index entries', async () => {
--- a/tests/unit/brainy/batch-operations.test.ts
+++ b/tests/unit/brainy/batch-operations.test.ts
@ -533,10 +533,8 @@ describe('Brainy Batch Operations', () => {
      expect(result.successful).toHaveLength(0)
      
      await brain.updateMany({ items: [] })
-      // removeMany is the exception (8.8.2): an empty id list is a refused
-      // selector, not an empty batch — deleting "nothing" silently was the
-      // bug class (a positional/bare-array call looked identical).
-      await expect(brain.removeMany({ ids: [] })).rejects.toThrow(/ids: \[\]/)
+      await brain.removeMany({ ids: [] })
+      // Should not throw
    })
    
    it('should validate batch size limits', async () => {
--- a/tests/unit/db/fact-log.test.ts
+++ b/tests/unit/db/fact-log.test.ts
@ -186,52 +186,4 @@ describe('fact log — round-trip, framing, reconcile, rotation, scan', () => {
    await log.sync()
    expect(log.segmentPaths()).toEqual([]) // only a tail exists — nothing sealed
  })
-
-  describe('scanFacts liveness contract (Stage-2 D1)', () => {
-    it('a wedged store fails LOUDLY within the first-batch bound — never a silent hang', async () => {
-      // Force a sealed segment (tiny rotateBytes) so the scan must READ from
-      // storage, then wedge that read: the exact production shape (a
-      // backlogged brain whose segment read never returned).
-      const mem: any = new MemoryStorage()
-      await mem.init()
-      const wedgeable = new FactLog(mem, { rotateBytes: 1 })
-      await wedgeable.open(0)
-      await wedgeable.append(fact(1))
-      await wedgeable.append(fact(2)) // second append rotates → seg 1 sealed
-      await wedgeable.sync()
-
-      const realRead = mem.readRawBytes.bind(mem)
-      mem.readRawBytes = (p: string) =>
-        p.includes('facts/seg-') ? new Promise(() => {}) : realRead(p) // hangs forever
-
-      const scan = wedgeable.scanFacts({ firstBatchTimeoutMs: 200 })
-      const started = Date.now()
-      await expect(scan.batches().next()).rejects.toThrow(/no first batch within 200ms/)
-      expect(Date.now() - started).toBeLessThan(5_000) // bound held, not a hang
-    })
-
-    it('a healthy scan is unaffected — first batch well inside the bound, all facts delivered', async () => {
-      for (let g = 1; g <= 5; g++) await log.append(fact(g))
-      await log.sync()
-      const scan = log.scanFacts({ batchSize: 2 })
-      const all: CommitFact[] = []
-      for await (const b of scan.batches()) all.push(...b.facts)
-      expect(all.map((f) => f.generation)).toEqual([1, 2, 3, 4, 5])
-      expect(scan.summary().factsYielded).toBe(5)
-    })
-
-    it('consumer think-time between pulls never counts against the producer', async () => {
-      for (let g = 1; g <= 4; g++) await log.append(fact(g))
-      await log.sync()
-      // Bound tighter than the consumer's pause: only the FIRST pull is
-      // raced, so a slow consumer after batch 1 must not trip the deadline.
-      const gen = log.scanFacts({ batchSize: 2, firstBatchTimeoutMs: 150 }).batches()
-      const first = await gen.next()
-      expect(first.done).toBe(false)
-      await new Promise((r) => setTimeout(r, 400)) // dawdle past the bound
-      const second = await gen.next()
-      expect(second.done).toBe(false)
-      expect((await gen.next()).done).toBe(true)
-    })
-  })
 })
--- a/tests/unit/db/generation-segments.test.ts
+++ b/tests/unit/db/generation-segments.test.ts
@ -1,150 +0,0 @@
-/**
- * @module tests/unit/db/generation-segments
- * @description The generation-segment store (Stage-2 D1+D3 file format).
- * Laws: (1) fold → read round-trips deltas and records byte-faithfully via
- * sidecar point-reads; (2) the manifest is the ONLY discovery path — reopen
- * reads one file, never a listing; (3) a lost/corrupt sidecar rebuilds from
- * its segment loudly, a damaged SEGMENT fails loudly (never silent wrong
- * data); (4) D3 reclaim drops whole segments only and bumps compactedBelow;
- * (5) the packed digest is deterministic across reopen; (6) immutability —
- * fold refuses overlap with sealed ranges.
- */
-import { describe, it, expect, beforeEach } from 'vitest'
-import { MemoryStorage } from '../../../src/storage/adapters/memoryStorage.js'
-import {
-  GenerationSegmentStore,
-  SEGMENTS_PREFIX,
-  type FoldGeneration
-} from '../../../src/db/generationSegments.js'
-
-const UUID = (n: number): string => `00000000-0000-4000-8000-${String(n).padStart(12, '0')}`
-
-const gen = (g: number, recordCount = 2): FoldGeneration => ({
-  generation: g,
-  timestamp: 1_700_000_000_000 + g,
-  delta: { generation: g, nouns: [UUID(g)], verbs: [], bytes: 123 + g },
-  records: Array.from({ length: recordCount }, (_, i) => ({
-    kind: (i % 2 === 0 ? 'noun' : 'verb') as 'noun' | 'verb',
-    id: UUID(g * 100 + i),
-    record: { metadata: { noun: 'document', v: g }, vector: { v: [g, i] } }
-  }))
-})
-
-describe('db/GenerationSegmentStore — the D1+D3 packed tier', () => {
-  let storage: MemoryStorage
-  let store: GenerationSegmentStore
-
-  beforeEach(async () => {
-    storage = new MemoryStorage()
-    await storage.init()
-    store = new GenerationSegmentStore(storage as any)
-    await store.open()
-  })
-
-  it('fold → read round-trips deltas and records via sidecar point-reads', async () => {
-    const meta = await store.fold([gen(1), gen(2), gen(3)])
-    expect(meta).toMatchObject({ firstGeneration: 1, lastGeneration: 3, frames: 3 })
-    expect(meta.checksum).toBeGreaterThan(0)
-
-    expect(store.hasGeneration(2)).toBe(true)
-    expect(store.hasGeneration(4)).toBe(false)
-
-    const d2 = await store.readDelta(2)
-    expect(d2?.delta).toEqual({ generation: 2, nouns: [UUID(2)], verbs: [], bytes: 125 })
-    expect(d2?.timestamp).toBe(1_700_000_000_002)
-
-    const records = await store.readRecords(3)
-    expect(records).toHaveLength(2)
-    expect(records![0]).toEqual({
-      kind: 'noun',
-      id: UUID(300),
-      record: { metadata: { noun: 'document', v: 3 }, vector: { v: [3, 0] } }
-    })
-    // Point read by id, both kinds.
-    expect(await store.readRecord(3, 'verb', UUID(301))).toEqual({
-      metadata: { noun: 'document', v: 3 },
-      vector: { v: [3, 1] }
-    })
-    expect(await store.readRecord(3, 'noun', UUID(999))).toBeNull()
-  })
-
-  it('reopen discovers everything from the manifest alone — no listing', async () => {
-    await store.fold([gen(1), gen(2)])
-    await store.fold([gen(3), gen(4)])
-
-    const reopened = new GenerationSegmentStore(storage as any)
-    await reopened.open()
-    expect(reopened.segments()).toHaveLength(2)
-    expect(reopened.hasGeneration(4)).toBe(true)
-    expect((await reopened.readDelta(1))?.timestamp).toBe(1_700_000_000_001)
-  })
-
-  it('a lost sidecar rebuilds from its segment; a damaged segment fails LOUDLY', async () => {
-    const meta = await store.fold([gen(1), gen(2)])
-    const idxPath = `${SEGMENTS_PREFIX}/seg-${String(1).padStart(20, '0')}.idx`
-    await storage.deleteRawObject(idxPath)
-
-    const reopened = new GenerationSegmentStore(storage as any)
-    await reopened.open()
-    // Rebuild path: still serves correct data.
-    expect((await reopened.readRecords(2))!).toHaveLength(2)
-
-    // Now damage the SEGMENT itself: flip a payload byte → CRC mismatch, loud.
-    const segPath = `${SEGMENTS_PREFIX}/${meta.file}`
-    const bytes = (await storage.readRawBytes(segPath))!
-    bytes[bytes.length - 3] ^= 0xff
-    await storage.writeRawBytes(segPath, bytes)
-    const damaged = new GenerationSegmentStore(storage as any)
-    await damaged.open()
-    ;(damaged as any).sidecars.clear()
-    await storage.deleteRawObject(idxPath) // force the sequential rebuild over damaged bytes
-    await expect(damaged.readRecords(2)).rejects.toThrow(/CRC mismatch|damaged/)
-  })
-
-  it('D3 reclaim drops whole segments only and bumps compactedBelow', async () => {
-    await store.fold([gen(1), gen(2)])
-    await store.fold([gen(3), gen(4)])
-    await store.fold([gen(5), gen(6)])
-
-    // Horizon mid-segment-2 (below 4): only segment 1 is FULLY below → drops.
-    const r1 = await store.dropSegmentsBelow(4)
-    expect(r1).toEqual({ dropped: 1, compactedBelow: 3 })
-    expect(store.hasGeneration(1)).toBe(false)
-    expect(store.hasGeneration(3)).toBe(true) // partial segment survives whole
-
-    // Bytes actually gone.
-    expect(await storage.readRawBytes(`${SEGMENTS_PREFIX}/seg-${String(1).padStart(20, '0')}.bgs`)).toBeNull()
-
-    // Horizon past everything: the rest drop; compactedBelow is durable.
-    const r2 = await store.dropSegmentsBelow(7)
-    expect(r2.dropped).toBe(2)
-    const reopened = new GenerationSegmentStore(storage as any)
-    await reopened.open()
-    expect(reopened.compactedBelow()).toBe(7)
-    expect(reopened.segments()).toHaveLength(0)
-  })
-
-  it('the packed digest is deterministic across reopen and changes with history', async () => {
-    await store.fold([gen(1), gen(2), gen(3)])
-    const atSeal = await store.digestThroughPacked(3)
-    const midSegment = await store.digestThroughPacked(2)
-    expect(atSeal).not.toBeNull()
-    expect(midSegment).not.toBeNull()
-    expect(midSegment).not.toBe(atSeal)
-
-    const reopened = new GenerationSegmentStore(storage as any)
-    await reopened.open()
-    expect(await reopened.digestThroughPacked(3)).toBe(atSeal)
-    expect(await reopened.digestThroughPacked(2)).toBe(midSegment)
-
-    await reopened.fold([gen(4)])
-    expect(await reopened.digestThroughPacked(4)).not.toBe(atSeal)
-  })
-
-  it('sealed segments are immutable — fold refuses overlap, requires ascending input', async () => {
-    await store.fold([gen(1), gen(2)])
-    await expect(store.fold([gen(2), gen(3)])).rejects.toThrow(/overlaps the packed tier/)
-    await expect(store.fold([gen(4), gen(4)])).rejects.toThrow(/strictly ascending/)
-    await expect(store.fold([])).rejects.toThrow(/at least one generation/)
-  })
-})
--- a/tests/unit/db/generationStore.test.ts
+++ b/tests/unit/db/generationStore.test.ts
@ -488,20 +488,6 @@ describe('db/GenerationStore', () => {
      expect(result.removedGenerations).toBe(2)
      store.release(2)
    })
-
-    it('timeBudgetMs bounds a pass; the next pass resumes the same prefix', async () => {
-      await manyGens(4)
-      // A spent budget (0ms) stops before reclaiming anything — an early stop
-      // is a consistent prefix, never a partial generation.
-      const bounded = await store.compact({ timeBudgetMs: 0 })
-      expect(bounded.removedGenerations).toBe(0)
-      expect(bounded.horizon).toBe(0)
-      // The next (unbounded) pass picks up exactly where the bounded one
-      // stopped and completes the same work.
-      const resumed = await store.compact()
-      expect(resumed.removedGenerations).toBe(4)
-      expect(resumed.horizon).toBe(4)
-    })
  })

  // ==========================================================================