v0.7.3

Parquet ZSTD support, vortex.patched encoder, constant-encoding selection fix, Windows TUI raw-mode fix.

Added

• Parquet: ZSTD-compressed Parquet import — zstd-jni was an optional dep in hardwood and had to be declared explicitly. NYC Yellow Taxi 2024-01 (47.6 MB Parquet, 2.96 M rows × 19 cols) imports to 40.7 MB Vortex — 14% smaller than the Rust JNI reference (47 MB) thanks to the global-dict encoder catching low-cardinality F64 columns.
• Writer: vortex.patched encoder — identifies outlier values that exceed the optimal bit width, zeros them in the inner array (exposed as an open cascade child for further bitpacking), and stores their within-chunk U16 indices and raw values separately.

Fixed

• CLI: Windows TUI raw-mode — readKey now calls ReadFile directly on the kernel handle obtained via GetStdHandle instead of reading from System.in. Java's System.in goes through JVM-internal CRT wrappers that ignore SetConsoleMode, so every keypress previously required Enter before the TUI reacted.
• Writer: constant encoding skipped for single-distinct-value columns — isDictCandidate returned true for distinctCount == 1, routing all-same-value columns through the global-dict path instead of vortex.constant.

Changed

• CLI: polling loop in Terminal.readKey(Duration) extracted to KeyDecoder.nextWithTimeout(InputStream, Duration) — eliminates duplication between PosixTerminal and WindowsTerminal.

Tests

• Integration: TaxiParquetOracleVsJavaIntegrationTest — hardwood reads the taxi Parquet to a CSV (oracle); ParquetImporter → CsvExporter produces a second CSV (SUT); line-by-line diff must be zero. Proves the importer loses no data across 2.96 M rows × 19 columns.

Full changelog: https://github.com/dfa1/vortex-java/blob/main/CHANGELOG.md#0.7.3

v0.7.2

CLI usability + reader robustness on real-world files (NYC Yellow Taxi).

Added

• CLI view <file> — scrollable Excel-like grid TUI. Streams rows on demand via a new LazyGridSource (one live chunk at a time, formats only the visible window). Title bar shows chunk K/N. Quit with q / Esc.
• CLI export writes to a derived <name>.csv next to the input file by default, with a stderr progress bar mirroring the import flow. Use export <file.vortex> - to stream to stdout, or export <file.vortex> out.csv for an explicit path.
• Reader ScanIterator.chunkRowCounts() — returns per-chunk row counts by walking the layout tree, no value decode. Used by the view TUI to plan navigation.
• Lazy vortex.decimal decode via new LazyDecimalArray record — zero-copy mmap slice + per-row BigDecimal materialisation. Replaces the GenericArray wrapper.
• 7 Offset*Array records (Long / Int / Short / Byte / Double / Float / Bool) + VarBinArray.SlicedMode for offset-based slicing of pre-decoded shared arrays.

Fixed

• Per-column chunking alignment. Files where one column has 1 mega-flat and another has N small flats (e.g. NYC Yellow Taxi 2024-01: 2.96M-row VendorID next to 23 × 131072-row datetime flats) now decode the wide column once into a sharedArena and slice it per chunk via Offset*Array. Previously the scan iterator emitted a single chunk whose datetime columns were the first 131072 rows only — silently dropping 95.6 % of the file.
• FrameOfReferenceEncodingDecoder now uses the arena variant of ArraySegments.of, so lazy children (e.g. LazyRunEndLongArray) materialise instead of throwing "no primary segment".

Docs

• Compatibility table refreshed: constant, varbinview, alprd, datetimeparts, decimal_byte_parts, decimal now reflect their shipped Lazy shape; container encodings (list / listview / fixed_size_list) marked Lazy (inherit child shape); patched pinned Materialized with reasoning.
• New ADR 0013 — policy for dropping Materialized fallbacks once Lazy ships.

Maven Central: io.github.dfa1.vortex:vortex-reader:0.7.2 (and vortex-writer, vortex-cli, etc.).

v0.7.1

Cleanup release on top of 0.7.0 — one more lazy encoding, a Windows TUI usability fix, and a fresh round of read benchmarks.

Added

• vortex.constant lazy decode — seven metadata-only LazyConstantXxxArray records (Long / Int / Double / Float / Short / Byte / Bool) replace the one-element broadcast buffer; the per-element broadcast-modulo path is gone (3edf6e8c)
• Top-N read benchmarks (N=10, 100) + README table, refreshed 80M-row numbers (c00fdf7f, 33714d7b, a6fd92fc)

Changed

• CLI: schema prints per-row column listing (9b3fe4b5)
• CLI: Terminal.readKey takes Duration instead of long ms (2942a4da)
• Reader: extract TimeDtype + TimestampDtype shared metadata helpers (8f1b9feb)

Fixed

• CLI: actionable error on Git Bash / MinTTY — GetConsoleMode failure now points users at winpty / Windows Terminal / PowerShell instead of dead-ending on the raw error (6ec42288)
• Reader: ArraySegments.of(arr) typed-accessor fallback for lazy arrays (74ec207b)

CI

• Drop sonar.cpd.exclusions (cde845bf)

Full changelog: v0.7.0...v0.7.1

v0.7.0

pco encoder (Classic + Consecutive delta + IntMult mode, 4-way tANS, multi-chunk, all 8 ptypes),
writer compression (~93% Rust JNI parity on NYC Yellow Taxi: 47.0 MB → 43.4 MB; stratified sampling, stats-driven cascade, sparse-cascade idx/val children, patched bitpacking),
lazy / zero-copy decode (ADR 0010 + ADR 0012: ALP / FoR / ZigZag / Chunked / Dict / RunEnd / RLE / Sparse / ALP-RD / VarBinView / DateTimeParts / DecimalByteParts now defer transform / materialisation until access),
write API ergonomics (DType static factories, structBuilder, typed writeChunk(Consumer<Chunk>) — ADR 0009),
Sonar pass (Codecov → SonarCloud, Javadoc HTML → Markdown, full S6218 / S7474 / S2184 / S3776 sweep).

Added

• vortex.pco encoder (PcoEncodingEncoder) — Classic mode + Consecutive delta + IntMult mode (mode=1); 4-way interleaved tANS; histogram + bin-optimization DP; multi-chunk (64K-element chunks); all 8 supported ptypes (I16/U16/I32/U32/F32/I64/U64/F64) (1bb14ab, 086aa52, 30579ed, 7219974, f856559)
• LeBitWriter — LSB-first bit writer, symmetric to LeBitReader; reusable for future bit-oriented encoders (1bb14ab)
• ADR 0009 — write API ergonomics: DType static factories + asNullable() (0e9d6703), DType.structBuilder() (63d66eef), typed writeChunk(Consumer<Chunk>) builder (ddb3e21a); design doc (d9c4b99, a57ea70); MemorySegment zero-copy overload split to ADR 0011 (6367eb37)
• ADR 0010 — lazy decode for 1:1 transform encodings: LazyAlpFloatArray, lazy FoR / ZigZag arrays defer the transform until first element access (cff3acb5, c47c055c, c3ca6951, 68186f8f)
• ADR 0012 — zero-copy decode for compound encodings. ChunkedXxxArray wraps instead of concatenating (dfe7aa34, c557b8fb, e2db153d); DictXxxArray lazy reads (9b97a1a5); lazy RunEnd (210449b5), RLE (f35f9a96), Sparse (b604f21c), ALP-RD (937ade36); VarBinArray.ChunkedMode (b3696f5a) + ViewMode for VarBinView (0eea0405); LazyDateTimePartsLongArray (8ab9ec70); LazyDecimalBytePartsArray (22887cb2); design doc (f6a19c47, 2578f892, 1c7f5950)
• ADR 0013 — compute primitives (masks, kernels, no-materialise) design doc (400e5b03)
• forEach* / fold default methods on Short / Byte / Bool array interfaces; chunked overrides iterate children directly (7dc6567e, f500afe3)
• truncateArray preserves zero-copy on ChunkedXxxArray (6f4eaa96)
• ALP size-based exponent search ported from Rust, two-step decode (f9bb7373)
• Decode shape table in docs/compatibility.md (47a91fd1)
• Writer compression closes ~93% of the Java↔Rust file-size gap on NYC Yellow Taxi 2024-01 (2.96M rows, 19 cols): 47.0 MB → 43.4 MB; Rust JNI baseline 42.8 MB. Four coordinated changes ported from vortex-compressor:
  • Global dictionary encoding admitted for F64 columns. Codes assigned in frequency-descending order so the dominant value maps to code 0, which lets SparseEncodingEncoder (fill = 0) compress the codes child. Mirrors Rust FloatDictScheme. Also: FrameOfReferenceEncodingEncoder skips cascade when ref == 0 and ptype is unsigned (residuals == input, FoR adds wrapper overhead for zero benefit) (01fbaa6)
  • Stratified sampling in CascadingCompressor: 32 contiguous strides at evenly-partitioned, non-overlapping offsets. Preserves local run structure so RunEnd/RLE can win on dict codes while covering breadth so cardinality-based encoders see realistic distinct counts. Matches vortex-compressor::sample::stratified_slices (715a697, da16f0d)
  • Stats-driven cascade selection. Single-pass ArrayStats (distinct count, top-frequency value + count) shared across all eligible encoders via merged StatsOptions. New Estimate sealed hierarchy (Skip / AlwaysUse / Ratio) lets encoders short-circuit the cascade without paying the sample-encode cost. ConstantEncodingEncoder.AlwaysUse when distinct == 1; DictEncodingEncoder.Skip when distinct > n/2 (Rust FloatDictScheme/IntDictScheme rule); SparseEncodingEncoder.Skip unless dominant-value bits == 0 and topFreq * 2 >= n; RunEndEncodingEncoder.Skip when every value is distinct. Mirrors vortex-compressor::estimate::EstimateVerdict (2e31265)
  • SparseEncodingEncoder.encodeCascade exposes patch-index and patch-value buffers as ChildSlot entries so the cascade further bitpacks them — biggest single lever (~1.7 MB on dict-coded F64 columns: tolls_amount, Airport_fee, congestion_surcharge, mta_tax, RatecodeID, improvement_surcharge) (2ad275c)
• Patched bitpacking — BitpackedEncodingEncoder picks the best bit_width and stores overflow as sparse patches; on trip_distance-style columns Java is 1.8 MB ahead of Rust JNI (007e6c47)
• Per-chunk zone-map stats shown in the TUI inspector (5e24fb62)
• Per-chunk column row-count consistency validation in the writer (c54c8dab)
• GlobalDictF64Test — round-trip + dict cardinality + sparse-codes-child verification on dominant-F64 columns (01fbaa6)
• TaxiColumnByteDiff — per-column byte attribution diagnostic. Walks the layout tree, prints Java vs JNI bytes side-by-side. Used to locate the sparse-cascade gap that the global file size hid (2ad275c)
• TaxiCsvSize diagnostic — reports CSV / CSV.gz sizes for the taxi corpus (7f851557, 5ba2ae30)
• ADR 0008 — domain primitives and unsigned integer representation (806f52f2)

Changed

• Primitive Array types are non-sealed interfaces; fold / forEach are default methods (aec4d813, f500afe3)
• FoR decode writes in-place when the source segment is writable; applyReference always allocates from the arena (b1906a08, 9955a39f)
• ALP eager fallback collapsed to a single allocate + transform pass (e3a6c21a)
• Arena lifted out of lazy array records into ArraySegments.of (8d6fe4f0)
• ScanIterator drops dead registry field (53dfdcbb)
• Per-chunk zone-map stats shown in TUI inspector (5e24fb62)
• Javadoc HTML tags → Markdown /// (44d2a052); {@code} → backticks (aca51d2f)
• CI: Codecov → SonarCloud, daily scheduled run (c600e3d0, 1e5816a5); failsafe + integration jacoco-it included in Sonar coverage (c59e2f6c, 03b2dfe7)
• CI: Mockito self-attach warning silenced via byte-buddy-agent (2ba7b877, 1183c526)
• OHLC read benchmarks re-run at 80M rows; -Dvortex.bench.ohlc.rows override added (9b7fd61f)
• dev.vortex:vortex-jni 0.74.0 → 0.75.0 ([2f55f1...

v0.6.0

proto-rewrite (protobuf-java → in-tree MemorySegment-native codec, CLI −14%),
Extension API split (ExtensionDecoder / ExtensionEncoder SPI, writer auto-route, UUID + nullable support, JDBC extension import),
module boundary cleanup (Array subtypes → reader.array, encode data holders → writer.encode).

Added

• proto-gen module — build-time .proto → Java record/enum generator (ae6c46a, 743278d, b527f84)
• ProtoReader / ProtoWriter — MemorySegment-native proto3 wire primitives (ae6c46a, b527f84)
• Oneof factories on generated records, e.g. ScalarValue.ofInt64Value(v) (b527f84)
• PatchedMetadata / VariantMetadata added to encodings.proto (743278d, b527f84)
• Nullable extension columns (vortex.date/time/timestamp/uuid) via ExtEncoding → MaskedEncoding → primitive (1015f9b)
• Null-preserving decodeAll on all extension decoders — null at invalid positions (24c64a9)
• ExtensionDecoder / ExtensionEncoder SPI with separate ServiceLoader manifests (a560563)
• Spec extension decoders: Date, Time, Timestamp, Uuid in reader.extension (a560563)
• Spec extension encoders: Date, Time, Timestamp, Uuid in writer.encode (a560563)
• Writer auto-routes List<LocalDate>, List<Instant>, List<UUID>, … to extension storage (1d54b57, 75d7b4b)
• vortex.uuid extension — FixedSizeList(U8, 16), big-endian, JDBC vendor detection (89a0a69, cce2d2d)
• JDBC import for DATE / TIME / TIMESTAMP / UUID columns (9f31d9e, cce2d2d)
• Chunk.as(name, Class) — typed extension column access (e5cefb0)
• ExtEncoding storage child cascade-compressed (FoR / Bitpacked / ALP / RLE / …) (33cf42e)
• Java → Rust nullable extension integration tests; UUID @Disabled pending vortex-jni upgrade (bb7fcb0)

Breaking

• EncodingRegistry → ReadRegistry in io.github.dfa1.vortex.reader (834d2f1, a560563)
• core.Extension / core.ExtensionEncoder → reader.ExtensionDecoder / writer.ExtensionEncoder (2a0ed93, a560563)
• VortexHttpReader.open gains HttpClient overload (235826f)
• core.array.* → reader.array.* — update import paths (286715c)
• core.array.NullableData → writer.encode.NullableData (286715c)
• Decode utilities (LeBitReader, PcoBin, PcoTansDecoder, SegmentBroadcast) → reader.decode (d514435)
• Encode data holders (ChunkedData, DateTimePartsData, FixedSizeListData, …) → writer.encode (d514435)
• ExtEncoding unwrap shortcut removed from registry (4d4ab34, 75d7b4b)
• ArrayNode.stats() / ArrayNode.of(…, stats) removed — was dead code in decode path (dc3aa00)

Changed

• regenerate-sources profile uses in-process proto-gen; protoc no longer needed (743278d)
• 25 encoding classes migrated to generated record API (meta.bit_width() style) (0132417, 743278d)

Fixed

• VortexHttpReader throws VortexException on HTTP body length mismatch (235826f)
• vortex.date / vortex.uuid metadata presence fixes Java → Rust cross-compat (bb7fcb0)
• Extension dtype nullable derived from storage dtype, not hardcoded false (1015f9b)
• DType.Extension.metadata capped at 64 KiB on parse (22a5f59)
• CLI startup: silenced dev.hardwood VectorSupport INFO log (57a5a38)

Removed

• vortex-reader dependency from vortex-parquet (eca40f4)
• com.google.protobuf:protobuf-java — CLI jar 14 MB → 12 MB; JDK 25 Unsafe warning gone (743278d)
• protoc build dependency (743278d)

Compatibility

1046 unit + 248 integration tests, JDK 25 (2 skipped — UUID cross-compat blocked on vortex-jni 0.74.0).

Performance

• ProtoWriter.varintSize branchless via Integer.numberOfLeadingZeros (42177ca)
• ProtoWriter backpatched length-delim writes eliminate per-message temp allocation (c79611e)

Documentation

• Compatibility doc bumped to Rust reference v0.74.0 (cf73887)

v0.5.0

The headline themes are an interactive inspector TUI for navigating Vortex files
(extracted as a dedicated vortex-inspector module), full Vortex extension type
decode (date, time, timestamp, uuid, decimal), and a scan API rewrite that
replaces the silent hasNext() arena-closing footgun with closeable Chunk objects.

Added

• Interactive TUI inspector (vortex-inspector module + tui CLI subcommand).
  Lazy-loaded layout tree with stats, dictionary entries, hex previews, and decoded
  data; works against local files and http(s):// URLs. FFM-based ANSI terminal
  driver — no Lanterna dependency. Documented in docs/how-to.md#inspect-interactively-tui.
  (aa7561f,
  397b64a,
  d4cd0bc,
  8dae240,
  00452e4,
  7a51165,
  e8db30a,
  a43f340)
• Extension type decode — vortex.date → LocalDate, vortex.time → LocalTime,
  vortex.timestamp → Instant / ZonedDateTime, vortex.uuid → UUID. Routed
  through a new Extension sealed hierarchy on DType.Extension. See
  docs/compatibility.md for the coverage matrix.
  (4963aa9,
  ca8d687,
  99417ad,
  9da2a78,
  175ad07)
• Decimal decode — GenericArray.getDecimal supports the decimal_byte_parts
  shape, including i128 (precision > 18). Width 1/2/4/8 reads stay allocation-free.
  (23d5019,
  4735324,
  ff20a24,
  f4ae8c0)
• CLI uber-jar deployed to Maven Central under classifier all
  (io.github.dfa1.vortex:vortex-cli:0.5.0:jar:all). Useful when the consumer
  environment can't clone from GitHub. The manifest sets Enable-Native-Access so
  FFM downcalls work without the JVM flag.
  (3e2c552,
  cfc5cc8)
• Writer: global dictionary for low-cardinality Utf8 — columns with ≤ 256
  distinct values across chunks are now emitted as a shared vortex.dict layout.
  (b4d1b43)
• CI: Windows runs for the inspector module.
  (a9c9d4e)

Changed

• Breaking — scan API lifecycle. ScanIterator now implements
  Iterator<Chunk>. next() returns a Chunk that the caller must close
  (try-with-resources); hasNext() is side-effect-free. Calling next() while a
  prior Chunk is still open throws IllegalStateException. This removes the
  previous footgun where iter.hasNext() silently closed the previous chunk's
  arena, invalidating any Array references the caller still held. Use after
  close() raises FFM's scope check (IllegalStateException) instead of returning
  undefined data. See the updated examples in README.md and
  docs/explanation.md#memory-model.
  (b45fd98)
• Breaking — EncodingRegistry is immutable. Register via the new builder:
  EncodingRegistry.builder().registerServiceLoaded().register(myEncoding).build().
  (64ffbaa)
• Breaking — inspect split into inspect (text) + tui (interactive).
  Previous inspect <file> behaviour stays on inspect; interactive use is now
  on the dedicated tui subcommand.
  (e8db30a)
• Extension sealed hierarchy replaces the prior Extensions utility class.
  (175ad07)
• CLI errors always print the exception class + cause chain — VORTEX_DEBUG
  environment variable removed.
  (6a4464b,
  f2f85bd)

Performance

• Bitpacked unpack — per-row bookkeeping hoisted out of the inner block loop
  in unpackLoop8/16/32/64. Measurable win on bitpacked scan benchmarks.
  (ab3ca3f,
  ad8a64d)
• Broadcast modulo branch-split — ALP + Dict hot paths gate the
  ConstantEncoding broadcast modulo behind a cheap cap == n check, restoring
  C2 vectorization on the common path. ~5–10× recovery on the regressed scans.
  (442021f)
• Scan fast-path on non-broadcast reads — recovers ~25% on bitpacked scans
  by skipping the broadcast capacity check when not needed.
  (051a794)
• GenericArray.getDecimal — width 1/2/4/8 reads stay allocation-free.
  (f4ae8c0)

Fixed

• Decimal element width is derived from the buffer size, not the declared
  precision — fixes round-trip with the Rust reference implementation for
  oversized declared precisions.
  (c798e95)
• Extensions.localDate bounds-check — rejects out-of-range storage values.
  (a7eab37)
• GenericArray.getDecimal rejects null cells in the mantissa path.
  (5198115)
• TUI thread safety — Layout.metadata byte reads run on the I/O worker
  thread that owns the handle. InspectorTree.Node uses identity equality so
  duplicate subtrees don't collapse.
  (6c732de,
  0cc1137,
  a47b6fd)
• InspectorTree — vortex.date columns format using the declared dtype;
  TUI data scan no longer applies withLimit (was rejecting GenericArray).
  (0e749df,
  b5ce1d6)
• ScanIterator.truncateArray now supports GenericArray; decimals format
  correctly in the TUI.
  (f09f564)
• CLI prints the exception class + full cause chain on inspect errors.
  (f2f85bd)

Removed

• ScanResult — renamed to Chunk and given lifecycle methods. Update imports:
  io.github.dfa1.vortex.scan.ScanResult → io.github.dfa1.vortex.scan.Chunk.
  (b45fd98)
• Extensions utility class — replaced by the Extension sealed hierarchy.
  (175ad07)
• Extension.Time#unit / Extension.Timestamp#unit accessors (unused).
  (2fcb311)
• VORTEX_DEBUG env-var gate — stack traces are always printed on CLI error.
  (6a4464b)
• Lanterna dependency — replaced by an FFM-based ANSI terminal in
  cli/src/main/java/.../tui/term.
  (397b64a)

Refactored

• Trailer parser extracted, shared by VortexReader (mmap) and
  VortexHttpReader (range-request) paths.
  (1ac6f5a)
• VortexHttpReader allocates its own Arena in the constructor and reuses
  a single HttpClient.
  (e18dafd)
• Inspector module carved out of cli; TUI + IoWorker + terminal code
  later moved back into cli (only the inspect package stayed in
  vortex-inspector).
  (aa7561f,
  77baff1)
• Documentation: layout section expanded (node types, encoding namespaces,
  pruning); on-disk file-layout diagram in explanation.md.
  (e696f07,
  5c2b410)

v0.4.0

The headline themes for this release are a security-hardening sweep of the file-format
parser, a public-API cleanup of the Array hierarchy (the heap-allocated buffer(int) /
segment() accessors are gone from the interface), and cascading writer features that
close the compression gap with the Rust reference implementation on real-world workloads.

Security

Every malformed input now surfaces as VortexException rather than a JDK exception
(IndexOutOfBoundsException, ArrayIndexOutOfBoundsException, StackOverflowError, raw
FlatBuffer/Protobuf runtime exceptions). Regression suite lives under
reader/src/test/java/.../*SecurityTest.

• Zip-bomb protection — ConstantEncoding and dict-layout decode no longer pre-allocate
  O(rowCount) memory; a 150-byte crafted file claiming 10⁹ rows is now constant-cost.
  (10a7776)
• Trailer + postscript validation — VortexReader and VortexHttpReader reject unknown
  file version, postscriptLen == 0, and postscriptLen > fileSize - 8. Footer/layout/dtype
  blob offsets and Layout.encoding index are bounds-checked at parse time.
  (f8f89fe)
• Footer segmentSpecs bounds — every spec is validated against fileSize the moment
  the footer is materialised, eliminating later IndexOutOfBoundsException on
  MemorySegment.asSlice.
  (03845ac)
• PType ordinal bounds-check — PType.fromOrdinal(int) replaces all 22 PType.values()[idx]
  call sites across encodings; crafted Protobuf ptype fields are rejected up front.
  (b4988c3)
• Layout-tree depth cap — PostscriptParser.convertLayout is capped at depth 64,
  preventing both unbounded nesting and self-referential FlatBuffer cycles (a ~120-byte
  cycle attack previously triggered StackOverflowError).
  (29adbe0)
• Layout metadata size cap — per-layout metadataAsByteBuffer() is capped at 4 MiB
  (above any real encoding's footprint; FSST's symbol table is the largest at ~32 KiB).
  (ebbe644)
• Decimal field validation — DType.Decimal is rejected unless precision ∈ [1, 38]
  and scale ∈ [0, precision], matching IEEE 754-2008 decimal128.
  (ebbe644)
• readFlatStats bounds-check — zone-map stats reads now validate the trailing
  little-endian fbLen field against the segment size, returning empty stats on malformed
  input rather than throwing IndexOutOfBoundsException from MemorySegment.asSlice.
  (ebbe644)

Added

• vortex.sequence F16 encode/decode — half-precision floats now round-trip through the
  sequence encoding.
  (7b3d7a9)
• Writer: cascading with global dict layout — low-cardinality columns (≤ 256 distinct
  values in the chunk sample) are now emitted as a vortex.dict layout, with the dict
  candidate detection tightened to avoid false positives.
  (53b2a19,
  d383765)
• Writer: opt-in Zstd compression — WriteOptions.withZstd(boolean) exposes the
  size/throughput trade-off. Off by default; turn on for archival workloads.
  (ea10d37)
• Encoding.decodeSegment extension point — added as part of the typed-segment migration
  (see Changed below). Provides a typed alternative to Array.segment().
  (ed4a0ae)
• DecodeContext.decodeChild(int, DType, long) — typed child-decode helper that replaces
  the per-encoding decodeChildAs(...) private utilities.
  (d07faf0,
  a1512da)
• Typed accessors on concrete array types — LongArray.segment(), VarBinArray.offsetsSegment(),
  MaskedArray.inner(), and friends now live on the concrete types where they fit cleanly,
  rather than on the Array interface.
  (84a34f4)
• *SecurityTest test-naming convention — adversarial / robustness tests are now grouped
  under the *SecurityTest suffix, mirroring the existing *IntegrationTest convention.
  Run with ./mvnw test -Dtest='*SecurityTest'.
  (76ba67c)
• FlatSegmentDecoder — extracted from EncodingRegistry; the registry is now pure
  dispatch.
  (4a08356)

Changed

• Array interface slimmed down. buffer(int), child(int), and segment() are no
  longer part of the Array interface; consumers should use the typed accessors on the
  concrete subtype (e.g. LongArray.segment()) or ArraySegments.of(arr) for a generic
  fallback. buffer(int) is now package-private on the concrete array types.
  (bdb4e7d,
  1283168,
  ba5957c,
  df6ab3f,
  bb7b656)
• VarBinArray no longer keeps a redundant offsetsArr field; consumers read offsets
  via offsetsSegment().
  (96687f8)
• ArrayStats is no longer eagerly stored on decoded array types; statistics are now
  read on demand from the FlatBuffer node, matching the Rust reference implementation.
  (9237e28)

Fixed

• MaskedArray.segment() delegates correctly to its inner array (regression introduced
  during the typed-accessor migration).
  (8a16119)
• Constant-encoded array indexing broadcasts the index correctly when scanning multiple
  rows from a single stored value.
  (ed658b7)
• Performance benchmark (RustWritesJavaReadsBigFileBenchmark) migrated off the removed
  Array.buffer(int) accessor, unblocking ./mvnw verify and ./bench.
  (977a529)

Removed

• Array.buffer(int), Array.child(int), and Array.segment() from the public Array
  interface (see Changed). Callers should migrate to the concrete-type accessors or
  ArraySegments.of(arr).
  (bdb4e7d,
  1283168)
• Encoding.decodeSegment(...) is removed after the migration to DecodeContext.decodeChild.
  (977a529)
• ArrayStats field on decoded array types (statistics are now lazy).
  (9237e28)

Documentation

• Added CONTRIBUTING.md covering trunk-based workflow, commit conventions, and the
  three-touch-point rule for adding encodings.
  (d9825cf)
• Added an internal-architecture diagram set covering the file format, layout tree, and
  scan path.
  (75f4cea)
• Added a "Vortex vs Parquet" comparison section to the README.
  (886bb80)
• Expanded the ## Security section in TODO.md with the open hardening roadmap (resource
  caps, per-encoding adversarial tests, Jazzer fuzz harness, OSS-Fuzz submission).
  (1bb1465)

Build & Tooling

• Dependabot enabled for Maven and GitHub Actions.
  (dd118a7)
• Numerous dependency bumps: JUnit Jupiter (5.11.4 → 6.1.0, tests now require JUnit 6),
  Mockito, FastCSV (3 → 4), H2 (2.3 → 2.4), Checkstyle, Zstd-JNI,
  maven-compiler/surefire/failsafe/javadoc/source/shade/gpg/antrun/exec/build-helper plugins,
  actions/checkout (4 → 6), actions/setup-java (4 → 5), actions/cache (4 → 5),
  Sonatype central-publishing plugin.
  (81be668,
  2c8319f,
  f6dbcf1,
  dfabd8c,
  7b4a718,
  fb9b404,
  7b67000,
  fd1ea7e)
• pom.xml files now group dependencies under production / testing comment sections
  with a consistent project-internal-first ordering.
  (bcbbbfd)
• Checkstyle scope tightened to exclude generated fbs/proto packages.
  (f5ab433)