LatticeDB 0.9.6 Release Notes

Summary

0.9.6 is an API ergonomics and storage-maintenance patch release. It adds
bounded typed edge traversal, stream publish sequence introspection, an explicit
adjacency-cache open option, and transaction-scoped all-node enumeration while
keeping existing APIs source-compatible.

The release also truncates checkpointed WAL files on close so reopened
databases do not keep scanning frames that are already durable in the data file.

Highlights

Bounded Typed Edge Traversal

The C API now supports typed traversal with a caller-specified limit:

lattice_edge_get_outgoing_by_type(txn, node_id, "KNOWS", limit, &edges);
lattice_edge_get_incoming_by_type(txn, node_id, "KNOWS", limit, &edges);

limit == 0 means unlimited. Limits are applied while collecting visible edge
references, before edge type strings are materialized for the public result
handle.

lattice_edge_scan(txn, edge_type_or_null, limit, &edges) is available for
administrative work such as index rebuilds, consistency checks, and export jobs.
It is intentionally documented as a scan, not a hot-path graph expansion API.

Python, TypeScript, and Go bindings expose matching typed traversal helpers:

• Python: get_outgoing_edges_by_type, get_incoming_edges_by_type
• TypeScript: getOutgoingEdgesByType, getIncomingEdgesByType
• Go: GetOutgoingEdgesByType, GetIncomingEdgesByType

Stream Publish Sequence APIs

Publish callers can now retrieve the stream sequence assigned inside the active
transaction:

lattice_stream_publish_get_sequence(txn, stream, stream_len, kind, kind_len, payload, &sequence);

The existing lattice_stream_publish API remains source-compatible and ignores
the returned sequence. The assigned sequence is durable only after commit; a
rolled-back transaction does not make the record visible.

Bindings expose the same capability:

• Python: publish_stream_get_sequence
• TypeScript: publishStreamGetSequence
• Go: PublishStreamGetSequence

lattice_stream_get_last_sequence is available as read-side introspection for
the last durable sequence in a stream.

Adjacency Cache Open Option

The C API adds lattice_open_options_v3 and lattice_open_v3 with
enable_adjacency_cache. Existing lattice_open and lattice_open_v2
behavior is unchanged.

Bindings now expose the option as:

• Python: enable_adjacency_cache
• TypeScript: enableAdjacencyCache
• Go: EnableAdjacencyCache

Transaction All-Nodes Snapshot

lattice_get_all_nodes_txn returns every node visible to a transaction
snapshot. It complements label-scoped transaction reads and keeps overlapping
readers isolated from uncommitted writer changes.

WAL Truncation After Checkpoint

Close now syncs and checkpoints before releasing the database handle, then
truncates the WAL to a header-only file after a full checkpoint. Future writes
continue with monotonic LSNs, while recovery no longer scans checkpointed frames
that are already durable.

API Notes

This release adds public API surface in C, Python, TypeScript, and Go. Existing
unfiltered edge traversal and stream publish APIs are unchanged.

Property lookup/index work is intentionally design-only in this release. See
docs/property_index_design.md for the planned explicit property-index and
scan-naming model. No scan-backed property lookup convenience API was added.

Upgrade Notes

This is a patch release with no database file-format bump beyond the format 3
layout introduced in 0.9.0.

Applications that want bounded graph expansion should prefer the typed traversal
APIs over client-side filtering of unbounded edge result sets. Use
lattice_edge_scan only for administrative and rebuild workflows.

Applications that need stream cursors immediately after publish can adopt the
new sequence-returning publish APIs without changing the existing commit model.

Validation Notes

Validation for this release included:

zig build test
zig build
python3 -m compileall -q bindings/python/src/latticedb bindings/python/tests
python3 -m pytest bindings/python/tests
cd bindings/typescript && npm run build
cd bindings/typescript && npm test -- --runInBand
cd bindings/go && go test -count=1 -tags repolocal ./...
python3 scripts/bump_version.py --check 0.9.6 --strict-lockfile

Regression coverage includes typed outgoing/incoming edge traversal with limits,
native edge scans with and without type filters, stream sequence assignment and
rollback behavior, lattice_open_v3 ABI layout, adjacency-cache traversal, and
transaction-scoped all-node visibility.