Add v0.1.30-rc.2 release notes

release-notes-v0.1.30-rc.2.md

@@ -0,0 +1,103 @@
+# Quarry v0.1.30-rc.2
+
+Quarry v0.1.30-rc.2 is a release candidate for the deterministic,
+language-neutral schema compiler and BRF serialization framework. This
+candidate completes the current generic C/QBS runtime milestone and adds a
+reproducible release-artifact workflow.
+
+## Highlights
+
+- Added deterministic QBS emission directly from `.brd` schemas.
+- Completed generic C encoding and decoded-value access for the currently
+  supported schema model, including nested records, record arrays, and
+  string/bytes arrays.
+- Fixed generated-C record identity across imported schemas.
+- Fixed generic-C record-array decoded views so public element access preserves
+  validated relationships.
+- Added a same-schema QBS-versus-generated-C benchmark baseline.
+
+## Compiler and QBS
+
+The schema compiler now supports:
+
+```text
+quarry-schema-compiler --emit-qbs output.qbs input.brd
+```
+
+The output is a deterministic binary QBS image containing the resolved schema,
+including imported metadata, and is consumable by the generic C runtime.
+Existing C, C++, and Python generation remains unchanged unless QBS emission is
+explicitly requested.
+
+## Generic C runtime
+
+Generic C now has release-confidence coverage for scalar values, enums,
+strings, bytes, primitive and enum arrays, string and bytes arrays, nested
+records, record arrays, presence/absence, and bounded validation/access. Public
+decoded-value access includes nested records and record-array elements. Unknown
+fields continue to be skipped according to the compatibility contract.
+
+## Generated C and interoperability
+
+Generated C now propagates canonical resolved-schema record identities across
+imported nested records and record arrays while preserving existing
+application-facing codec entry points. Generated C and QBS-driven generic C
+produce matching canonical BRF for the benchmark workload, with cross-runtime
+validation coverage.
+
+## Benchmark baseline
+
+The benchmark uses `benchmarks/schemas/workload.brd` and one logical workload
+for both implementations. Measured local optimized results are:
+
+- QBS image: 881 bytes.
+- Generated schema-specific object artifacts: 13,464 bytes.
+- BRF payload: 252 bytes for both paths.
+- QBS-driven encode: approximately 3.2x generated C.
+- QBS-driven post-validation access: approximately 2.8x generated C.
+
+These are platform-specific baseline measurements, not universal performance
+claims. The object/QBS artifact ratio compares schema-specific artifacts only;
+it is not a complete application-footprint comparison because both approaches
+also require runtime/support code.
+
+## Release and packaging
+
+Release tooling now builds deterministic source tar and zip archives, Python
+wheel and sdist artifacts, release notes, and a SHA-256 checksum manifest.
+Source archives carry version fallback metadata and can be reconstructed,
+configured, built, installed, and tested without `.git` metadata. Artifact
+validation checks required contents, package metadata, and development-file
+contamination.
+
+## Compatibility
+
+- C++ generated-code API epoch: `3`.
+- C generated-code API epoch: `2`.
+- Python generated-code API epoch: `1`.
+- Schema IR version: `1`.
+- QBS format version: `1`.
+- BRF format version: `2`.
+
+BRF v2 was introduced after `v0.1.30-rc.1` and is the current BRF contract;
+RC1 BRF v1 artifacts must not be assumed wire-compatible with this candidate.
+QBS format 1 records the BRF format used by its resolved schema metadata.
+Generated code and runtime components should be taken from the same Quarry
+release and matching generated-code epoch.
+
+## Known limitations
+
+- Nested arrays are unsupported.
+- Recursive by-value records are unsupported.
+- Maps, unions/variants, and bit-fields are outside the current schema model.
+- Protocol Buffers translation remains limited to the documented supported
+  subset.
+- Benchmark timing is advisory and platform-specific.
+
+## Validation
+
+Current main passed native build and test, clang-tidy, coverage baseline,
+Cortex-M cross-build, benchmark workflow, strict C99/interoperability coverage,
+and complete CTest (`52/52`). Release artifact reconstruction passed configure,
+build, install, and CTest; wheel installation/import passed. The sdist build
+requires network access to obtain isolated build dependencies.