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+# Changelog
+
+All notable changes to the `mxaccess` workspace are documented here. The
+format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/);
+the workspace as a whole follows [SemVer](https://semver.org/) but the
+0.0.x line is pre-release / API-unstable.
+
+## [Unreleased] — V1 — 2026-05-06
+
+V1 is the first publishable cut. Closes M0 → M6 from
+`design/60-roadmap.md`.
+
+### Added
+
+- **`mxaccess-codec`** — pure protocol codec covering `MxReferenceHandle`,
+  `NmxTransferEnvelope`, `NmxItemControlMessage`, `NmxWriteMessage` (scalar
+  + array, normal + timestamped), `NmxSecuredWrite2Message`,
+  `NmxSubscriptionMessage` (single + multi-record DataUpdate per F44),
+  `NmxReferenceRegistrationMessage`, `NmxMetadataQueryMessage`,
+  `NmxOperationStatusMessage`, `ObservedWriteBodyTemplate`, ASB Variant +
+  `AsbStatus` + `RuntimeValue`, `MxStatus`, `MxValueKind`, `MxDataType`,
+  `MxValue`. Counting-allocator bench harness in `benches/alloc_count.rs`
+  (F38) reports 1–4 allocs per write across the proven matrix, well under
+  the R12 < 5/write target.
+- **`mxaccess-rpc`** — DCE/RPC PDU codec, NTLMv2 client + server-direction
+  packet-integrity verify (F2 with `subtle::ConstantTimeEq`), TCP
+  transport, OBJREF parser + Win32 `CoMarshalInterface` emitter (F6),
+  `IObjectExporter::ResolveOxid` + `ResolveOxid2` (F10),
+  `IRemUnknown::RemQueryInterface` + `RemAddRef`/`RemRelease` (F11).
+- **`mxaccess-callback`** — RPC server hosting `INmxSvcCallback` +
+  `IRemUnknown` for inbound `DataReceived` / `StatusReceived` frames.
+- **`mxaccess-nmx`** — `INmxService2` client (`RegisterEngine2`,
+  `TransferData`, `AddSubscriberEngine`, `SetHeartbeatSendInterval`,
+  etc.) plus auto-resolving `NmxClient::create` factory (F12, gated by
+  `windows-com`).
+- **`mxaccess-galaxy`** — `tiberius`-backed `Resolver` + `UserResolver`
+  (F14, gated by `galaxy-resolver`).
+- **`mxaccess-asb-nettcp`** — `[MS-NMF]` framing + `[MC-NBFX]` binary-XML
+  + `[MC-NBFS]` static dictionary + DH/HMAC/AES auth crypto with
+  constant-time `mod_exp` via `crypto-bigint::DynResidue` (F27).
+- **`mxaccess-asb`** — `IASBIDataV2` client (`Connect`, `RegisterItems`,
+  `Read`, `Write`, `PublishWriteComplete`, `CreateSubscription`,
+  `AddMonitoredItems`, `Publish`, `DeleteMonitoredItems`,
+  `DeleteSubscription`, `Disconnect`) with canonical-XML HMAC signing
+  for all 13 `ConnectedRequest` shapes (F28) and DataContract
+  field-suffix names on the binary `MonitoredItem` body (F34).
+- **`mxaccess`** — async Tokio façade exposing `Session`, `AsbSession`,
+  `Subscription` (`Stream<Item = Result<DataChange, Error>>`),
+  `subscribe_buffered` per R2 single-sample-with-cadence-knob
+  semantics (F36), `recover_connection` reconnect loop (F16), recovery
+  events (`RecoveryEvent::Started/Recovered/Failed`), and a typed
+  `Error` taxonomy. Optional `metrics` feature emits per-op counters,
+  latency histograms, and connection-state gauges (F40).
+- **`mxaccess-compat`** — `LMXProxyServer`-shaped Rust facade exposing
+  the 18-method `ILMXProxyServer5` surface as async fns over
+  `mxaccess::Session` / `AsbSession` with a `Mutex<HashMap<i32,
+  ItemRef>>` handle table and `Stream`-based event channels (F35).
+- **Examples** — `connect-write-read.rs`, `subscribe.rs`,
+  `subscribe-buffered.rs`, `asb-subscribe.rs`, `multi-tag.rs`,
+  `recovery.rs`, `secured-write.rs`, plus diagnostic
+  `asb-relay.rs`. Live-probe DoD verified end-to-end against the
+  AVEVA install.
+- **Tooling** — `cargo public-api` baselines under
+  `design/public-api/{crate}.txt` with CI drift check (F41).
+  `design/M6-bench-baseline.md` records the alloc-count baseline.
+
+### Changed (vs the .NET reference)
+
+- `NmxSubscriptionMessage::parse_data_update` accepts `record_count >= 1`;
+  the .NET reference hard-throws on `record_count != 1`. F44 evidence
+  walk against `captures/094-frida-buffered-separate-writer/`
+  documents the multi-record observation that drove the divergence.
+- `subscribe_buffered` returns a `Stream<Item = DataChange>`
+  (single-sample-per-event); per R2 verification the cadence is a
+  server-side delivery rate knob, not a multi-sample payload.
+
+### Known limitations
+
+- **F3** — cross-domain NTLM Type1/2/3 fixture is permanently
+  out-of-scope on the dev host (single-domain). Single-domain wire
+  parity is verified; cross-domain is documented but not regression-
+  tested.
+- **F45** — recovery replay for buffered subscriptions falls through
+  to plain `AdviseSupervisory`, losing the `.property(buffer)`
+  registration. Filed as a follow-up.
+- **F46** — `LmxProxy.dll!CLMXProxyServer.Suspend`/`.Activate` wire
+  emission was not instrumented; the compatibility-server's
+  client-side gating is documented but the underlying ORPC call
+  shape is unconfirmed.
+- **R3 / R4** — `OperationComplete` trigger conditions and
+  completion-only byte mappings are unmapped in both the .NET
+  reference and the Rust port. Frame bytes are preserved verbatim
+  via `Session::operation_status_events()`.
+
+## Publish order
+
+Workspace crates form a dependency DAG; `cargo publish` requires
+already-published deps to exist on crates.io, so the order matters.
+For V1 cut:
+
+1. `mxaccess-codec` (no internal deps)
+2. `mxaccess-rpc` (no internal deps)
+3. `mxaccess-asb-nettcp` (no internal deps)
+4. `mxaccess-galaxy` (depends on codec)
+5. `mxaccess-callback` (depends on rpc + codec)
+6. `mxaccess-asb` (depends on codec + asb-nettcp)
+7. `mxaccess-nmx` (depends on codec + galaxy + rpc + callback)
+8. `mxaccess` (depends on all the above)
+9. `mxaccess-compat` (depends on mxaccess)
+
+`cargo publish --dry-run` validates each crate's metadata + tarball
+in isolation; the dependent crates' dry-runs require the leaf crates
+to actually exist on crates.io (the registry lookup happens regardless
+of `--no-verify`). For pre-publish verification: leaf crates dry-run
+in CI; dependent crates are validated by the public-api baseline +
+build-test-clippy matrix.