0.4.0 "Sentinel" — the governed-answer release

Where Goshawk opened the doors (MCP, A2A, /v1, cross-language crypto), Sentinel stands guard over what comes through them.

• TypeDID envelope auth on /v1 (serve --require-auth): x-qg-envelope bound to the request path and body hash, Ed25519-verified against the envelope's did:key; failures are 401 receipts carrying the contract.
• POST /v1/answer and the semantic-model registry (models/import/{osi,croissant}, models, search).
• MCP stdio server (mcp-serve): dependency-free JSON-RPC 2.0, same governed surface as /v1.
• Reverse crypto direction closed: PyTypeDidEnvelope::signed mints qg-python-compatible envelopes (same seed → same did:key).
• Stack realigned to the 0.12 substrate wave: Grust 0.12.0 "Lobster", TypeSec 0.12.0 "Torcello", LakeCat 0.3.0 "Ocelot" — 40/40 green.
• A second book: The QueryGraph Stack guide (docs/guide), plus the review deck and tri-format one-pager; the dedicated book gains the Goshawk/Sentinel chapter.

See CHANGELOG.md.

0.3.0 "Goshawk" — the interoperability release

First network surface: /v1 HTTP API (health, navigator bundles, qglake story, envelope audit, semantic-model registry + search) and the A2A Agent Card at /.well-known/agent-card.json. Verifies qg-python Ed25519 TypeDID envelopes cross-language (verify-envelope CLI, agent::interop). OpenLineage run ids are spec-conformant deterministic UUIDv5, validated against the official 2-0-2 schema in the equivalence suite. GitHub Actions CI.

See CHANGELOG.md for full notes.

QueryGraph 0.2.0 "Peregrine"

First named QueryGraph release — codenames are birds of prey (see RELEASES.md).

Tracks Grust 0.11.0 "Crab", TypeSec 0.11.0 "Burano", LakeCat 0.2.1 "Lynx".

Highlights

• Crab Cypher adoption — the LakeCat catalog graph and the Dataverse semantic graph are interrogated with grust-cypher reads (CALL db.labels(), MATCH (t:Table) RETURN count(t)), the same queries a live Sail backend pushes down.
• Burano audit-safe attestations — the TypeDID envelope now carries VerifiedTypeDidMessage::attestation() fields (action / resource / privacy / profile / envelope digest).
• LakeCat qglake-bundle migration — the catalog gate now verifies bundles through LakeCat's shared qglake-bundle crate (canonical QueryGraphBootstrap + verify_manifest) instead of a hand-maintained copy of the wire format.
• Human-size modules — the source is split so every file is ≤500 lines.

25 tests pass, clippy clean. See docs/blog/announcing-querygraph-stack.md for the full story.