diff --git a/PROGRESS.md b/PROGRESS.md
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+# SPL service Rust conversion — lane progress
+
+## Current state
+
+- Worktree: `spl-rust-lane-a` at `5ed4dacb8`.
+- Frozen interface contract, seam inventory, and decided scope were reread after scope-check
+  correction #2. Scope numbering is canonical: U1 HPKE, U2 blob receive, U3 buffering /
+  admission / health, U4 relay client, U5 supervisor, U6 cutover.
+- The initial direct U3 draft was rejected after the supervisor clarified that direct work fails
+  the experiment. The delegated admission + health rewrite is accepted; buffer and base-mode
+  HPKE delegate returns are under review. Base-mode HPKE is accepted; the buffer unit is held
+  on a discovered zero-window divergence.
+- U3 admission + health and U1 base-mode HPKE are accepted after focused gate reruns and lane
+  review. The U3 A4 error-path mutation experiment remains pending with blob receive; the U1
+  Python-generated parity corpus remains pending before Python deletion.
+- U1 auth-mode HPKE is accepted after independent review: the RFC 9180 oracle opens and exports
+  the expected bytes, focused lint/test/iOS gates are green, and its sender-SPKI failure remains
+  distinct. U2's corrected HPKE blob-frame unit and U4 relay-health state are accepted after
+  combined test, lint, and iOS gate reruns. The U5 pure posture/token gate is accepted after
+  exact-posture, redaction, cache-invalidating state-transition, test, and lint review. U2
+  archive safety and U4 relay control are accepted after parity corrections and a 41-test
+  combined crate rerun. U2 ledger parsing and content-type units plus U4 reconnect backoff are
+  accepted after a 58-test combined crate rerun. U4 tunnel routing and U5 lifecycle
+  transition state are accepted after a 65-test combined crate rerun. The corrected U1 CLI
+  parser is accepted after it restored the `-v`/`-d` service surface while retaining the
+  no-key-on-argv rule for HPKE. U4 loopback piping is accepted after a 67-test crate rerun
+  proved initial-prefix replay and reverse forwarding. U4 tunnel-status classification and U5
+  read-only link-state/token loading are accepted after the 79-test combined crate rerun; U2
+  authenticated blob preparation is accepted after its real auth-HPKE/archive/exporter
+  round-trip. The corrected U2 fresh-ledger reader is accepted after a focused three-test
+  rerun: an already-running reader observes Python's incomplete-to-complete browser record
+  immediately, and file disappearance/non-list content fail closed.
+- The corrected U5 shutdown function is accepted after a focused two-test rerun: it awaits
+  `stop()` for tunnel cleanup, then aborts and awaits the separately-owned listen task. The
+  full A7 live-WebSocket test remains pending with relay-client composition; this unit records
+  the necessary task-cancellation half and makes no false claim that `stop()` closed a socket.
+- The supervisor resolved both held blockers: U2 uses split `WsByteSource`/`WsByteSink` halves
+  without changing U3, and the HPKE CLI uses fixed-count u32be field framing with redacted
+  error classes. Resume U2 via delegated sink, receiver, and CLI framing units. AC-4 fixture
+  generation is supervisor-owned; U6 remains blocked until the supervisor supplies its fixture
+  commit.
+- Checkpoint gates after the correction-driven units: `cargo fmt --all -- --check`, strict
+  combined clippy, and combined locked tests are green (85 SPL + 12 HPKE); both HPKE and SPL
+  libraries pass the explicit `aarch64-apple-ios` check without an exclusion; `cargo deny`
+  and the Rust 1.95 locked check are green. Final gate evidence must be rerun after the
+  remaining orchestration work.
+
+## Instrumentation
+
+### Rejections
+
+- **U3 direct draft — rejected.** It was written by the lane owner before the supervisor's
+  correction. The code had focused green tests, but it generated none of the experiment's
+  delegated-authoring evidence. This is a process/brief defect, not a claim that the behaviour
+  was wrong. Delegated rewrites now replace it.
+- **U4 relay control — returned.** The first review found an error-classification gap; the
+  revision then failed the first compiled integration gate because its string and numeric
+  branches returned different types. The writer is repairing the typed return rather than the
+  lane owner bypassing the delegated unit. The repaired return passed 41 combined tests and
+  lint. This is a detector firing as intended.
+- **U1 CLI parser — returned.** The first parser return correctly protected HPKE secrets from
+  argv but omitted the existing service `-v`/`-d` surface required by C8. This was a brief
+  omission caught against `service.py`; the corrected parser passed 27 focused tests.
+- **U5 state/token reader — returned.** The first return read `tokens/account.json` directly
+  beneath the journal instead of the frozen `link/tokens/account.json` location. The writer is
+  correcting the on-disk path; its next return also needed Python's primary-token truthiness
+  before legacy fallback. Integration then exposed a direct unused import and test-only
+  `assert!(false)` arms under the crate's no-panic clippy gate. This is a contract-review
+  catch plus a brief defect: the initial unit brief did not require the crate gate.
+
+### Explained twice
+
+**HPKE dependency shape** had to be explained twice: the base-mode writer first stopped on an
+invalid `hpke` feature set, then on mismatched `rand_core` feature/direct `p256` types. The
+corrected brief is `hpke` `alloc` + `nistp` + `aes` + `getrandom`, plus direct `p256` 0.14 for
+the seam's PKCS#8/SPKI boundary. This was a brief defect, not code rework.
+
+### Frozen-contract ambiguities
+
+- **HPKE crate feature/dependency shape:** the plan's availability claim named `hpke = 0.14.0`
+  but did not state its feature names or the incompatible `p256`/`rand_core` major versions.
+  The delegated base-mode writer stopped before coding and reported the exact compile failure.
+  The workspace dependency is corrected to the crate's `alloc`/`nistp`/`aes`/`getrandom`
+  feature set plus matching direct `p256`; this is a brief defect, not an interface-contract
+  change.
+- **HPKE subcommand field framing — resolved by supervisor:** u32be-length fields, a 96 MiB
+  cap, exact five/four input fields and one/two output fields, plus a one-line fixed error
+  class with no stdout. This was a contract defect, not a delegate rejection.
+- **WebSocket progress zero values:** Python raises `ValueError` for `window_s <= 0` and allows
+  a zero byte minimum; the Rust frozen error vocabulary contains only timeout/closed cases. The
+  delegated buffer unit proposed `ProgressTimeout` for a zero window and bounded-read semantics
+  for a zero minimum. This is held rather than silently accepted.
+- **U2/U3 WebSocket ownership — resolved by supervisor:** the transport splits into distinct
+  read and write halves. `BufferedWsReader<R>` retains its accepted read-only ownership and U2
+  receives a sibling `WsByteSink` for `READY`/`ACK`/close. This was a contract defect, not a
+  delegate rejection.
+
+### Contract rework
+
+- **U2 blob receive boundary:** scope-check correction #2 added the missing U2 contract and
+  fixed the unit numbering. The earlier blob-frame placement return was caused by this frozen
+  contract defect, not by a delegate failure; the corrected HPKE-crate implementation remains
+  accepted and is excluded from the delegate-rejection count.
+- **U4/U5 shutdown boundary:** the corrected observable contract is no live relay socket once
+  the supervisor stops the client. `RelayClient::stop()` alone is insufficient; the service
+  must cancel the listen-run task. This is pending implementation and seam A7 validation.
+- **Fixtures:** AC-4 corpus generation and its provenance commit are supervisor-owned because
+  this worktree has no Python fixture environment. The lane will not fabricate or block on it.
+- **U3 buffered-wire reads:** scope-check correction #2's no-direct-slice rule also reached
+  `peek` and `peek_bounded`. Their checked-range follow-up is accepted after seven focused
+  buffer tests; it preserves U3 behavior and is contract rework, not a rejection.
+- **U2 split transport and U1 CLI framing:** the supervisor rewrote both frozen sections after
+  the lane stopped rather than inventing an escape hatch or wire format. Both are contract
+  rework (ledger row 3), not delegate rejections; the U4 concurrent pipe makes the split
+  independently necessary.
+
+### Surgical direct fixes
+
+- **Shared HPKE error enum:** added `InvalidSenderPublicKey` to the U1 base-mode error type so
+  the delegated auth-mode unit can preserve its distinct sender-SPKI failure class. This spans
+  the U1 base/auth function units and is an integration correction, not a behaviour change.
diff --git a/core/crates/solstone-core-spl-hpke/src/lib.rs b/core/crates/solstone-core-spl-hpke/src/lib.rs
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+// SPDX-License-Identifier: AGPL-3.0-only
+// Copyright (c) 2026 sol pbc
+
+//! RFC 9180 primitives for the SPL home-service conversion.
+
+mod auth;
+mod base;
+mod blob_frame;
+
+pub use auth::{OpenedHpke, open_auth};
+pub use base::{HpkeError, P256Secret, SealedHpke, open_base, seal_base};
+pub use blob_frame::{
+    ACK_LEN, BLOB_ID_LEN, BlobFrameError, MAX_CIPHERTEXT_LEN, MalformedOffer, OFFER_LEN, Offer,
+    READY_LEN, SENDER_FINGERPRINT_LEN, ack, parse_offer, ready,
+};
diff --git a/core/crates/solstone-core-spl/src/lib.rs b/core/crates/solstone-core-spl/src/lib.rs
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+// SPDX-License-Identifier: AGPL-3.0-only
+// Copyright (c) 2026 sol pbc
+
+//! The standalone SPL home-service runtime.
+//!
+//! The service-facing I/O adapters are intentionally kept out of this first
+//! layer. Buffering, admission, and health vocabulary are pure so every
+//! transport implementation shares the same owner-visible behaviour.
+
+mod admission;
+mod authenticated_blob;
+mod authorized_client_ledger;
+mod authorized_clients;
+mod blob_archive;
+mod blob_content_type;
+mod health;
+mod link_state_files;
+mod loopback_pipe;
+mod posture_gate;
+mod reconnect_backoff;
+mod relay_control;
+mod relay_health;
+mod relay_status_failure;
+mod service_shutdown;
+mod service_transition;
+mod tunnel_route;
+mod ws_buffer;
+
+pub use admission::BlobAdmissionGate;
+pub use authenticated_blob::{
+    AuthenticatedBlobError, PreparedAuthenticatedBlob, prepare_authenticated_blob,
+};
+pub use authorized_client_ledger::{AuthorizedClientLedger, BrowserLedgerLookup};
+pub use authorized_clients::{
+    AuthorizedClients, BrowserUploadAuthorization, ClientEntry, LedgerStatus,
+    parse_authorized_clients,
+};
+pub use blob_archive::{
+    BlobArchiveEntry, BlobArchiveError, BlobArchiveMetadata, ValidatedBlobArchive,
+    parse_blob_archive,
+};
+pub use blob_content_type::blob_content_type;
+pub use health::{
+    LINK_HEALTH_EVENT, OFFLINE_TUNNEL_REASONS, REASON_HOME_MISSING_MOBILE,
+    REASON_LOCAL_PRIVATE_LISTENER_UNREACHABLE, REASON_RELAY_ADMISSION_SATURATED,
+    REASON_RELAY_TUNNEL_REJECTED, REASON_RELAY_TUNNEL_UNREACHABLE, REASON_SERVICE_TOKEN_REJECTED,
+};
+pub use link_state_files::{
+    LinkServiceToken, LinkServiceTokenRead, LinkState, LinkStateRead, load_link_service_token,
+    load_link_state,
+};
+pub use loopback_pipe::pipe_loopback;
+pub use posture_gate::{
+    PostureGate, PostureInput, RelayBlocked, RelayDecision, RelayPermit, ServiceToken, TokenInput,
+};
+pub use reconnect_backoff::{
+    INITIAL_RECONNECT_BASE, MAX_RECONNECT_BASE, ReconnectBackoffError, ReconnectSchedule,
+    schedule_reconnect,
+};
+pub use relay_control::{
+    ListenControl, bearer_authorization_value, parse_listen_control, relay_tunnel_url,
+    websocket_endpoint,
+};
+pub use relay_health::{RelayHealth, RelayHealthState, RelayTunnelFailure};
+pub use relay_status_failure::{RelayTunnelFailureSignal, classify_relay_tunnel_failure};
+pub use service_shutdown::{RelayStop, ServiceShutdownError, stop_relay_run};
+pub use service_transition::{
+    PostureObservation, ServiceAction, ServiceLifecycle, TokenObservation, transition,
+};
+pub use tunnel_route::{TunnelRoute, route_tunnel_prefix};
+pub use ws_buffer::{BufferedWsReader, WsBufferError, WsByteSource, WsClosed};