Changelog highlights

Highlights per release, inlined below so this page stands alone (condensed at release time from the engine repository’s CHANGELOG — provenance only; everything you need to evaluate a release is here). Until 1.0, the API and on-disk format change without backward-compatibility guarantees; format changes migrate via dump/load.

v0.3.1 (2026-09)

Header-only fix: corvid.h is portable C11/C++. The generated header had been wrapping every frozen enum in C23 fixed-underlying-type guards (#if __STDC_VERSION__ >= 202311L + : uint32_t), whose pre-C23 fallback (typedef uint32_t corvid_status; beside the enum tag) is ill-formed C++ — the tag and the typedef share a namespace there. Found by corvid-cpp (the C++ binding), which had to preprocessor-mask the guards in its ABI translation units. The header now emits the plain typedef enum { ... } corvid_xxx; the FFI spec has always shown — valid C11, C23, and every C++ standard; verified by compiling a trivial TU both ways against the published artifact’s header. Values, signatures, and the 124-symbol surface are unchanged; the Rust-side #[repr(u32)] wire-type pin is untouched; FFI_VERSION and the soname stay at 1. C++ consumers drop their workarounds at the next pin; existing v0.3.0 pins keep working (the C-level surface did not move).

v0.3.0 (2026-09)

The C ABI’s first additive expansion — no engine storage or query changes; two new FFI symbols (Appendix A 122 → 124), both inside FFI_VERSION = 1:

• corvid_value_map_keys — a map’s keys as a string cursor in ascending key-byte order (non-maps answer an empty cursor, inert). Bindings could previously read a map’s values only by known key; key enumeration needed a candidate-key oracle.
• corvid_phrase_search — the direct positional text search (consecutive in-order analyzed tokens; stop words collapse out of adjacency; most relevant first, ties by key) returning a rows cursor whose score is the hit’s BM25 phrase sum. k == 0 answers an empty cursor. The query builder’s .text source stays bag-of-words — phrase semantics had no ABI path before this.
• Golden fixtures gained executable lines (map-key enumeration, phrase cases) — bindings re-vendor golden/ at their pin bump. No signature, enum value, or behavior change; the soname and FFI_VERSION stay at 1.

v0.2.1 (2026-08)

Fixes to the v0.2.0 release artifacts — no engine/API changes:

• darwin dylib install name is @rpath/libcorvid.dylib and the Linux .so carries its SONAME — the v0.2.0 artifacts were unloadable by external consumers (found by corvid-c; verified in-pipeline).

v0.2.0 (2026-08)

The big one — the C ABI, plus a hardening/roadmap-execution program:

• The C ABI (corvid-ffi): a 122-symbol typed cdylib + generated corvid.h, FFI_VERSION = 1 locked contract, golden fixtures, C smoke suite (122/122 symbols), header drift gate, 3-OS release CI, ASan/UBSan/LSan job (zero leaks), per-platform release archives. Documents through value handles — no parsing anywhere; measured at parity with native Rust (0.99–1.02×).
• CJK text search: sliding-bigram tokenization for Han + kana runs (dictionary-free), phrase-order-correct (東京タワー matches, タワー東京 doesn’t); stemming/folding never apply to CJK. Re-create pre-existing text indexes.
• New sketches: CuckooFilter (deletable membership, rollback-on-full), TDigest (streaming quantiles/CDF), MinHash + LshIndex (set similarity + candidate lookup).
• In-memory PQ (create_vector_index_pq) with the persisted codebook; parallel PQ training (2.6–4.1×, bit-identical codebooks).
• Dump format v2 (u64 length prefixes; loader accepts v1 and v2); load_with_renames for legacy __-containing names.
• zstd feature (transparent document compression ≥1 KiB, ~12× on text) and tracing feature (structured events: backfill, compaction, plan shapes, semantic cache).
• Durability/consistency program: single-snapshot queries/aggregations/ traverse/page; O(degree) graph-edge cascades via derived adjacency (ratified link trade); crash-safe index creation with resume; compound prefix-only windows (all_docs_indexed); sort indexes (SortIndex); density-driven verify batching; exact-rerank ANN hits (Hit.approximate); plan_shape()/PlanShape; semantic CAS equality (NaN/−0.0); name validation (no interior __/NUL — breaking); antimeridian bbox + geo validation; execution-time RRF/MMR/BM25 argument validation; order_by class rules (audit C4); auto-compaction of on-disk vector indexes; Store::begin_bulk thread-local bulk scopes.

v0.1.1 (2026-05)

• Release workflow builds corvid-mcp for all desktop/server platforms (Linux x86_64/aarch64, macOS Intel/Apple Silicon, Windows x86_64).

v0.1.0 (2026-05)

The first release — the embedded engine complete:

• Transactional KV over redb; typed Value model with deterministic codec; document layer with fluent Collection handles, insert_auto ordered keys.
• Vector search (cosine/dot/L2, exact KNN + persistent HNSW, .approx() filtered-ANN path), BM25 full-text with incremental inverted indexes, phrase/positional search, CJK-ready tokenizer with S-stemmer.
• The multi-modal query builder: filter + vector + text + RRF + MMR + order_by/offset + select + limit; aggregations global and grouped; keyset pagination; selectivity-driven index choice; identity-hashable QueryPlan/PlanCache; bounded ranked execution.
• Indexes: scalar, compound, text (in-RAM + on-disk), geo, on-disk HNSW (quantized variants), on-disk PQ.
• Graph (link/neighbors/traverse), geo (radius/bbox/k-nearest), joins, semantic cache, reactive change feeds, sketches (HLL + Bloom), TTL, schemas with unique constraints.
• Operations: online backup, logical dump/load, compaction, bulk load; MCP sidecar over stdio; on-disk format version marker; WASM (wasm32 engine + 0.2 MB harness), iOS/Android cross-compiles.
• Autovectorized distance kernels under #![forbid(unsafe_code)].