Promotes `subtype?: string` to a top-level standard field on every entity,
alongside `type` / `confidence` / `weight`. Flat string, no hierarchy — the
consumer-chosen vocabulary for sub-classifying entities within a NounType
(Person → employee/customer, Document → invoice/contract, etc.).
Layer 1 — subtype field + rollup
- HNSWNounWithMetadata.subtype + STANDARD_ENTITY_FIELDS entry
- Entity / Result / AddParams / UpdateParams / FindParams threading
- add()/update() persist subtype on storageMetadata + entityForIndexing
- get()/find() route through the standard-field fast path
- subtypeCountsByType (Map<NounTypeIdx, Map<subtype, count>>) on
BaseStorage, mirrored after nounCountsByType with the same self-heal
rebuild and persisted to _system/subtype-statistics.json
- brain.counts.bySubtype(type, subtype?) — O(1) point + breakdown
- brain.counts.topSubtypes(type, n) — top-N by count
- brain.subtypesOf(type) — distinct subtypes seen
- find({ type, subtype }) and find({ subtype: ['a','b'] }) on the fast path
Layer 2 — trackField for other facets
- brain.trackField(name, { perType?, values? }) registers a field for
cardinality + per-NounType breakdown stats. Backed by the aggregation
engine (auto-defines __fieldCounts__<name>), backfill-on-define applies.
- brain.counts.byField(name, { type? }) returns value frequencies
- Optional vocabulary whitelist rejects off-vocabulary writes at add/update
Layer 3 — generic migrateField
- brain.migrateField({ from, to, readBoth?, batchSize?, onProgress? })
streams every entity, copies the value from one path to another, and
(unless readBoth) clears the source. Supports top-level standard fields,
metadata.X, and data.X paths. Idempotent — safe to re-run.
Docs
- New guide: docs/guides/subtypes-and-facets.md (Layer 1 + 2 + 3)
- README, DATA_MODEL, QUERY_OPERATORS, api/README, finite-type-system,
quick-start all treat subtype as a core primitive with anonymous example
vocabularies (employee/customer/invoice/milestone).
Tests
- 26 new integration tests covering write/read/update/delete round-trips,
counts rollup decrement + re-route on mutation, trackField + byField
with and without perType, vocabulary whitelist enforcement, and
migrateField for metadata.X → subtype and data.X → subtype paths
including readBoth deprecation-window semantics.
Unit suite: 1468/1468 passing. Type-check + build clean.
- groupBy now supports { field, unnest: true }: an entity contributes once per
distinct element of an array field (tag frequency / faceted counts). Duplicate
elements on one entity count once; an empty/missing array joins no group. The
incremental add/update/delete paths fan out across the unnested groups.
- extractEntities/extractConcepts batch-embed the unique candidate spans in one
embedBatch call instead of one embed() per candidate (N sequential model calls);
falls back to per-candidate embedding if the batch fails. No behavior change.
New report APIs:
- brain.queryAggregate(name, params) returns the clean AggregateResult[] shape
({ groupKey, metrics, count }) directly, instead of the search-Result wrapper that
find({ aggregate }) returns.
- HAVING: find({ aggregate, having }) and queryAggregate filter groups by computed
metric values (e.g. revenue > 1000), complementing where (which filters group keys).
Evaluated per group: O(groups), independent of entity count.
Fixes (all reproducible on Node; surfaced under Cortex+Bun by Memory):
- Aggregate backfill-on-define: defining an aggregate over a store that already holds
matching entities returned []. It now backfills from existing entities on first query
(storage-agnostic via getNouns), so it works under durable backends that reopen
pre-populated. groupBy:['noun'] resolves to the entity type; find({ aggregate }) rows
expose groupKey/metrics/count at the top level.
- Multi-hop find({ connected: { depth, via } }) honors depth and via at every hop
(was 1-hop only, with verb filtering applied to hop 1 only); BFS bounded by limit.
- extractEntities no longer bleeds a neighbour's type indicator across candidates; each
candidate is typed by its own span. Also fixes the "Dr." title pattern.
Adds real-embedding regression tests; full unit suite green.
Three advanced-API correctness fixes, all reproducible on Node (not Bun-specific):
- Entity/concept extraction returned []. SmartExtractor combined agreeing signals
with a weighted sum compared against an absolute 0.60 gate, so a confident
low-weight signal lost selection to a mediocre high-weight one that then failed
the gate, dropping the whole result. Select and gate on a normalized weighted
average instead. The public `confidence` option now controls the threshold (was
a dead hardcoded 0.60), and the embedding-signal timeout is raised 100ms -> 2000ms
so the neural signal is not silently dropped on slower runtimes.
- Multi-hop find({ connected }) returned only the 1-hop neighbour. executeGraphSearch
ignored depth/via; it now delegates to the depth-aware neighbors() BFS.
- find({ aggregate }) hid groupKey/metrics/count under .metadata, so callers
expecting AggregateResult saw empty rows. Expose those fields at the top level.
Adds real-embedding regression tests in tests/integration/advanced-apis-regression.test.ts.
Two production correctness defects fixed together so consumers can land
one upgrade.
BR-FIND-WHERE-ZERO — find() returned [] and stats() reported 0 entities
for any workspace whose data was written after the 7.20.0 column-store
refactor. Root cause: getStats() and the getIds() fallback still read
from the deleted sparse-index path. Separately, BaseStorage.getNounType()
was hardcoded to return 'thing', poisoning type-statistics.json with
every noun attributed to that bucket.
- MetadataIndex.getStats() reads from ColumnStore + idMapper.
- MetadataIndex.getIdsFromChunks() throws BrainyError(FIELD_NOT_INDEXED)
when neither store has the field. getIdsForFilter() catches per
clause, logs once, returns [].
- BaseStorage.nounTypeByIdCache populated in saveNounMetadata_internal
and consumed in saveNoun_internal. flushCounts() now persists the
Uint32Array counters too, so readers see fresh per-type counts.
- Self-heal at init: loadTypeStatistics() auto-rebuilds when the
poisoned signature is detected. rebuildTypeCounts() is now public for
use from `brainy inspect repair`.
- Dead state removed: dirtyChunks, dirtySparseIndices,
flushDirtyMetadata().
BR-DEFENSIVE-INTERFACE — 7.21.0 called supportsMultiProcessLocking()
unconditionally, crashing on older Cortex storage adapters that predate
the method. New hasStorageMethod(name) helper gates every new-method
call site. Older adapter triggers a one-line warning at init pointing
at the recommended plugin version.
Tests:
- new tests/integration/find-where-zero.test.ts (7 cases)
- new tests/integration/cortex-compat.test.ts (5 cases)
- multi-process-safety.test.ts updated to enforce correct counts
- 1329/1329 unit + 24/24 new integration tests passing
Filesystem storage now enforces single-writer, many-reader semantics.
A second writer on the same data directory throws at init time with the
holder's PID, hostname, and heartbeat — replacing the previous silent
stale-reads failure mode.
- New: `Brainy.openReadOnly()` — coexists with a live writer, every
mutation throws clearly.
- New: writer lock at `<rootDir>/locks/_writer.lock` with 10s heartbeat
and stale-detection (PID liveness + heartbeat freshness).
- New: cross-process flush-request RPC (filesystem-based, no signals)
so inspectors can force fresh state on demand.
- New: `brain.stats()`, `brain.explain(findParams)`, `brain.health()`
for operator-facing introspection.
- New: `brainy inspect` CLI with 13 subcommands (stats, find, get,
relations, explain, health, sample, fields, dump, watch, backup,
repair, diff), all read-only by default.
- Same-PID re-opens allowed with a warning (preserves test "simulate
restart" patterns).
- Storage instances passed directly via `storage: new MemoryStorage()`
are now honoured instead of silently falling through to the
filesystem auto-detect path.
Brainy + Cortex compose under this model — the lock covers both because
they share `rootDir`, Cortex segments are immutable mmap files, and
MANIFEST updates use atomic-rename.
