DreamDBv0.2.0bec026

DreamDB v0 — Spec Index

A single navigable entry point for the DreamDB v0 specification. Maps every Open Question (OQ) to its resolution and points at every spec document.


The 21 Spec Documents

Read in order; each document inherits vocabulary and decisions from the ones before it.

#DocumentWhat it pins down
0spec/0000-overview.mdVocabulary, four first principles, three-layer architecture (App → SDK → HTTP → Object Store)
1spec/0001-data-model.mdFive entities (Space, Timeline, Track, Item, Manifest); three Track kinds; Item ≠ Object
2spec/0002-content-addressing.mdBLAKE3, deterministic CBOR, address grammar, modality-tag grammar, paged Index Pages
3spec/0003-time-encoding.mdu64 ns ticks, integer-only arithmetic, 16-char hex, billion-scale sizing
4spec/0004-spatial-indexing.mddreamdb.lsh-cosine, ChaCha20 hyperplanes, multi-table & multi-probe levers
5spec/0005-backend-interface.mdHTTP contract, Manifest Supremacy, ETag normalization, HTTP/2 mandate
6spec/0006-protocol-operations.mdEight verbs, per-session cache, GC algorithm, Stream prefetch, Ref freshness
7spec/0007-streaming-encapsulation.mdCMAF Fragments, Spatial Bucket layout, Index Page byte format, dynamic B-tree height
8spec/0008-versioning-collab.mdManifest DAG, branching, merging, MUST-refuse-on-incompat, monotonic-ts
9spec/0009-conformance.mdConformance roles, test categories, meta-OQ resolutions (CBOR tags, multihash)
10spec/0010-vector-compression.mdVectorCompressor Object, dreamdb.qinco-cosine, modality compress= suffix, re-rank contract — draft, Phase 3
11spec/0011-scalar-indexing.mdNative scalar filtering: B-tree / bitmap algorithms, ScalarIndex Object — draft, Phase 2
12spec/0012-federation.mdFederation Manifest, federate verb (resolves OQ-40), cross-cluster scatter-gather — draft, Phase 3
13spec/0013-graph-indexing.mdVamana / DiskANN — GraphIndex + GraphPage Objects; router GraphIndex for cross-shard — draft, Phase 3
14spec/0014-streaming-extensions.mdPath A item chunking (ItemManifest), Path B CMAF renditions (RenditionPlaylist) — draft, Phase 3
15spec/0015-hybrid-retrieval.mdTextIndex + MultiVectorIndex; HybridQuery verb; RRF default fusion; query planner cost model — draft, Phase 4
16spec/0016-streaming-freshness.mdHotShard delta tier; dreamdb.fresh-vamana-cosine; index-health signal; bounded-staleness contract — draft, Phase 4
17spec/0017-schema-evolution.mdMulti-version modalities; Reencode verb; compatible_with planner hint — draft, Phase 4
18spec/0018-multi-tenant.mdPer-Space quotas; tenant_id in capability tokens; TenantUsageBatch; fair-share scheduling — draft, Phase 4
19spec/0019-encryption.mdConvergent + per-Space modes; EncryptionMeta header; KMS abstraction — sketch, Phase 4
20spec/0020-tombstones.mdTombstoneListObject; per-Space dreamdb.tombstones registry; read-side suppression filter — Phase 5

Open Questions: Audit

87 OQs total across v0 + Phase-3 + Phase-4 drafts. v0 (OQ-1–43): 41 resolved actively, 2 deferred to v0.1+. Phase-3 (OQ-44–61): formally opened by drafts 0010/0012/0013/0014 — most deferred to first implementation pass. Phase-4 (OQ-62–87): formally opened by drafts 0015–0019 — most deferred to first implementation pass; the 9 OQs in 0019 are sketch-level and block the spec/0019 sketch→full-draft promotion.

Resolved within v0 (29 OQs)

OQTopicResolution
OQ-1Genesis-relative vs. absolute origin0003 §2 — Genesis-relative canonical, optional Unix-ns back-ref
OQ-2Spatial-indexing scheme0004 §5 — dreamdb.lsh-cosine
OQ-3Backend consistency model0005 §5 — strong RAW for content; linearizable CAS for refs
OQ-4Per-modality container0007 §5 — CMAF / fragmented MP4
OQ-5Manifest distribution0008 §8 — Refs / hash-addressed / pull-only / federation
OQ-6Modality-tag grammar0002 §5 — dot-separated; reverse-DNS for user-defined
OQ-7Constant correction conflicts0008 §6.3 + 0007 §8.2 — lex-greatest layer wins
OQ-8Event bucketing default0007 §8 — Time-batch format; per-modality bucket-duration
OQ-9Spatial bucket-key derivation0004 §5 — ChaCha20-seeded LSH-cosine
OQ-10Default Fragment duration0007 §5.4 — 2 s default; 1–30 s range
OQ-11Concrete CBOR tag numbers0009 §3.2 — private-use range 65521–65525
OQ-12Multihash algorithm tags0009 §3.1 — 0x1e (IPFS-aligned)
OQ-13Spatial+time segment order0007 §6.5 — spatial-first
OQ-14Index Page fanout & size0007 §7.1 — B = 256, 16 KiB target
OQ-15Inline-vs-paged threshold0007 §7.2 — 1 MiB
OQ-16Per-modality byte layout0007 §6 — fixed-size + offset-table patterns
OQ-17CBOR tag for time anchor0009 §3.2 — 65524
OQ-20Index Page delta encoding0007 §7.3 — deltas for time; positional arrays
OQ-22Local-FS Connector0005 §9 — HTTP-only in v0; MinIO for dev
OQ-23Vector storage layout0007 §6 — inline (default) vs. reference (multi-table)
OQ-24Bucket-splitting rule0007 §6.4 — 100 MiB threshold
OQ-27LSH conformance vectors0009 §5.3 — multi-arch f32 discipline
OQ-28Adaptive widening / speculative preload0006 §6.4 / §6.5 — implementation-defined
OQ-29HTTP version requirement0005 §6 — HTTP/2 mandatory
OQ-30HTTP test vectors0009 §6 — full battery
OQ-33Verb conformance vectors0009 §7 — full battery
OQ-35Explicit parent for Publish0008 §4.2 — Publish(parents: [...])
OQ-36Byte-format vectors0009 §5.4 — full battery
OQ-39DAG conformance vectors0009 §8 — full battery

Decided "no" in v0; may revisit in v0.1+ (2 OQs)

OQTopicv0 decision
OQ-19Negative time anchorsv0: forbidden (unsigned u64). v0.1 may add bias scheme.
OQ-21Byte-size delta encodingv0: as-is, no delta. v0.1 may add if benchmarks justify.

Deferred to v0.1+ as feature additions (7 OQs)

OQTopicRationale
OQ-18Coarser time resolutions (ms, s)v0 ns is sufficient; revisit if storage waste measured
OQ-26dreamdb.lsh-l2 algorithmL2-metric modalities; v0 cosine-only
OQ-31Multipart uploadv0 caps Bucket Objects at 100 MiB; multipart unneeded
OQ-32Presigned-URL ConnectorWeb/browser deployment pattern
OQ-34Subscribe / Watch verbv0 is pull-only via Ref polling
OQ-37Additional media codecsAV1, HEVC, FLAC, VP9 — all CMAF-compatible
OQ-41tag namespaceImmutable Refs (release tags)

Resolved in Phase-3 / Phase-4 spec drafts (4 OQs)

OQTopicResolution
OQ-25dreamdb.pq-ivf algorithm0010 §7 — superseded by dreamdb.qinco-cosine (NeurIPS 2025); classical PQ sketched in 0010 §11.1
OQ-38PQ-compressed vector layout0010 §8 — bucket header extends to 200 bytes carrying vector_compressor_hash
OQ-40federate verb0012 §4 — push + pull modes with capability tokens (Ed25519)
OQ-54Streaming graph updates0016 §4 — dreamdb.fresh-vamana-cosine ships append + background consolidation + tombstone deletes

Deferred to community / governance process (2 OQs)

OQTopic
OQ-42Public registry of conformance reports
OQ-43Conformance suite release cadence

Foundational Doctrines (cross-cutting)

The spec accumulates several disciplines that span multiple documents. Quick reference:

DoctrineDefined inWhy
Time as the sole primary key0000 §5.1No user-level IDs; everything joins via timeline
Strict immutability for content; CAS for refs0000 §5.2Lock-free data plane; refs are the only mutable thing
Address = <object-address> · <intra-object-locator>0000 §5.3Item ≠ Object; bucketing makes 1B-scale viable
Streaming-native encapsulation0000 §5.4Fragment-as-Item; index = seek pointer
Manifest Supremacy0005 §5.3.1Hot path uses cached object_index; LIST is bootstrap-only
Universal byte-range URIs0002 §6.5All dreamdb:// URIs use #bytes:<a>-<b> form; opaque to readers
Integer-only time arithmetic0003 §4.1Zero f64 ops on the time path
F32 left-fold determinism0004 §5.4Bit-identical LSH across hardware paths
Pure-scalar reference is canonical0009 §5.3.1SIMD paths verified against scalar
Lineage validation at decode time0007 §6.1.1Bucket headers carry spatial_index_hash
MUST-refuse-on-SpatialIndex-incompat0008 §6.5Catastrophic silent-merge case at v0; non-conformance gate
Feature-branching at scale0008 §3.1Per-user/team Refs; coordinator merges into refs/main
Monotonic ts (observability)0008 §7.3SHOULD; never trusted for correctness

What's Next

The v0 spec is complete and the reference implementation is shipping. Current focus:

  1. Billion-scale validation: imagenet-1k (1.3M records) ingest in progress 2026-05-18; SIFT1M / LAION-100M next.
  2. Production hardening: observability spec, cross-SDK interop tests, RBAC / capability tokens (deferred to v0.1).
  3. Tombstone storage compaction (per spec/0020 §6): operator pass that reclaims bytes for tombstoned anchors.
  4. Multi-parent merge formalization: design/0007-sharded-ingest.md documents the algorithm; may be promoted to its own spec number.

See README.md for the project pitch, status table, and quickstart.


Spec Status

FieldValue
Spec versionv0 + Phase-3 (0010/00120014) + Phase-4 (00150019) + Phase-5 (0020)
Document count21 (00000020)
Open Questions87 total — 45 resolved (v0 + Phase-3/4/5); 42 open or deferred to first-implementation pass
Reference implementationshipping (dreamdb-* crates, dreamdb-dataset-python, browser SDK)
Conformance suitepartial (CBOR / address / time / spatial covered; cross-SDK interop deferred)
Test suite721 green across crates
Billion-scale benchmarkin progress (1.3M-record imagenet-1k ingest 2026-05-18)