T7: proves slice-4's Reflex<TapAudioPipe> + LocalVadReflex decorates the
trunk leg's TapAudioPipe identically; barge-in fires on PSTN caller speech
through the same state machine as WebRTC caller speech.
T8: MockRealtimeBrain + BrainShim drives a synthetic PSTN caller through the
FOB reflex loop end-to-end: loud PCM -> local VAD trips -> barge kills ->
brain reply -> un-mute -> idle timeout (caller hangup) closes the session.
Dev-dependencies added to rutster-trunk/Cargo.toml so the integration tests
reach MockRealtimeBrain, futures-util, and tokio-tungstenite without pulling
FOB source into the trunk crate.
Signed-off-by: Aaron D. Lee <himself@adlee.work>
Step A -- minimal-viable T5 surface (no ThreadSession refactor):
* MediaLeg enum { WebRTC(RtcSession), Trunk(TrunkSession<TapAudioPipe>) }
+ as_webrtc_mut + channel_id + channel_state + is_closed + set_tap_handle
helpers (dead_code-suppressed per AGENTS.md with documented rationale;
Step B will wire them).
* run_per_leg_tick dispatch pub fn matching on MediaLeg: WebRTC => media
crate's loop_driver::drive (unchanged), Trunk => rutster_trunk's
loop_driver::drive (NEW slice-5). The seam gate holds: trunk leg never
enters the media crate's loop_driver.rs.
* MediaCmd::RegisterTrunk variant + placeholder arm (drops mpsc ends,
drops oneshot reply without sending -- pump task's reply_rx.await
returns Err + closes WSS gracefully per the existing cmd-rejection
posture for Register admission control).
* Two HTTP routes: POST /v1/trunk/sessions (503 stub -- the originate
handler needs the CallControlClient trait threaded into AppState,
Step B or dev-b handover) + POST /v1/trunk/webhook (returns TwiML
with hardcoded loopback Media Streams fork URL -- T5 Step B + dev-b's
TwilioCredentials env parser will populate webhook_base).
* main.rs: spawned trunk_register relay task that converts
RegisterTrunkInboundChannel -> MediaCmd::RegisterTrunk + awaits
oneshot reply, plus mounts TwilioMediaStreamsServer::router alongside
the existing /v1/sessions routes.
Step B (deferred to follow-up commit / dev-b handover):
* Full ThreadSession refactor to use leg: MediaLeg instead of rtc:
RtcSession for the WebRTC code path's existing tests (4 tests).
* Actual RegisterTrunk handler body (spawn_tap_engine + Reflex +
LocalVadReflex composition + TrunkSession construction).
* ADR-0009 honoring verification (TwilioCredentials never flow through
this module -- the call_sid + tap_url fields are operational
correlation IDs, not credentials).
* T7 reflex-on-trunk + T8 PSTN-sim e2e integration tests, which
pin behavior end-to-end + force the Step B refactor's correctness.
ADR-0007 honored: zero SIP bytes parsed; wire surface in this commit is
JSON Twilio Media Streams protocol + HTTP/REST + axum router merge.
Signed-off-by: Aaron D. Lee <himself@adlee.work>
In-core ~30-line table-driven codec (no dep). The ITU-T G.711 µ-law
companding formula is a piece of telephony history worth teaching (AGENTS.md
learner-facing comment mandate). 3× linear upsample on decode; 3× decimation
downsample on encode. The resampler artifacts are below the barge-in trigger
threshold (LocalVadReflex only needs RMS energy); rubato lands in a post-
spearhead refinement if a downstream consumer needs better (spec §6.6).
Task T1 of slice-5 — T3 (TwilioMediaStreamsServer) consumes this codec.
Signed-off-by: Aaron D. Lee <himself@adlee.work>
ADR-0007 lands in code:
- Rename crates/rutster-signaling-sip → crates/rutster-trunk. The crate was
a stub anyway (lib.rs with a doc-comment + crate_compiles() test); the
rename locks the new boundary shape — the future rented-transport
ingress (CPaaS media-leg fork / out-of-tree SBC glue, **no SIP stack**)
lands here at spearhead step 5.
- rutster-trunk/src/lib.rs doc-comment now describes the ADR-0007 split:
CPaaS media-leg adapter as primary, out-of-tree SBC for on-prem
graduation. Cross-refs ADR-0007 + ADR-0008 (FOB vs. green zone: trunk
is green zone; SIP lives outside the trust boundary).
- rutster-spend/src/lib.rs doc-comment updated to quote ADR-0007's
'rutster mediates both the provider call-control API and the brain tap'
framing — the spend gate sits in that boundary, structurally preventing
a runaway brain from exceeding spend/pacing. Pulling spend out into a
service re-introduces the 3-vendor structural hole.
Cargo bumps:
- edition = '2024' (slice-1's pinned Rust 1.85 + edition-2024 floor
already requires this; rutster-media's let-else pattern in
OpusDecoder::decode · Slice-2's let-else in AcceptOffer's Uuid
parse_str · all rely on edition 2024's stabilized let-chains / let-else).
- repository = 'https://git.adlee.work/alee/rutster' (the self-hosted
Gitea remote — matches 'git remote -v' origin). The github.com/anomalyco
URL was stale from the pre-pivot copy.
- Cargo.lock regenerated by cargo for the rename.
No behavioral code changes — the trunk crate's body is still the stub
crate_compiles() test. FOB membership (per ADR-0008) is unchanged:
rutster-trunk will be FOB-internal at step 5 because it's the media-leg
ingress (hot path); spend-spend stays FOB because spend is
security-constitutive.
- run_tap_client: drives a connected WebSocketStream with a tokio::select!
over rx_pcm_in (inbound PCM → audio_in WS frame) and ws.next() (brain
frame → audio_out mpsc or control handling).
- Handshake: send hello, await brain hello (bounded 2s timeout).
- seq gap detection (log + count, never drop on gap — spec §3.1).
- Hot-path errors (encode/decode failures, send/recv failures) are logged
+ counted; TapClientError is returned only on graceful close, hello
timeout, or WS errors. The TapEngine (Task 7) decides reconnect policy.
- Pure-helper unit test (elapsed_ms); full pump behavior is exercised
against the in-process EchoServer in the Task 8 integration test.
Spec ref: 2026-06-28-slice-2-agent-tap-design.md §4.2.
- Add tokio-tungstenite 0.24, futures-util 0.3, url 2, base64 0.22 to
[workspace.dependencies] (spec §8.1).
- Add crates/rutster-tap-echo as 7th workspace member (spec §2).
- Transition crates/rutster-tap/Cargo.toml from stub to real manifest
with the deps Tasks 2-4 will need (rutster-media, tokio, tokio-tungstenite,
serde, serde_json, base64, url, thiserror, tracing).
- Skeleton lib.rs (compile test) + main.rs (placeholder fn main) for
rutster-tap-echo; Task 5 fills in the echo logic.
- Verify cargo deny check passes against the new transitive dep tree.
Spec ref: docs/superpowers/specs/2026-06-28-slice-2-agent-tap-design.md §2, §8.1.
Four routes on axum 0.7 per spec §4.1: POST /v1/sessions (mint),
POST /v1/sessions/:id/offer (str0m-native SDP accept), DELETE
/v1/sessions/:id (close), GET / (static HTML client). Session store is
a DashMap<ChannelId, Arc<Mutex<RtcSession>>> (spec §4.5); one tokio
task drives all session poll loops — per-session tasks would pre-pave
the wrong pattern for step 4's dedicated thread. Graceful shutdown
drops the DashMap on Ctrl-C / SIGTERM. Integration test exercises the
REST surface; manual browser e2e per README §6.5.
str0m 0.21's default crypto backend pulls rcgen 0.14.8 and time
0.3.51, both of which require rustc 1.88+. The workspace toolchain
is pinned to 1.85 (edition 2024 floor, the str0m MSRV). Pin rcgen
to 0.14.7 and time to 0.3.41 in Cargo.lock so the str0m tree
builds on the pinned toolchain. No source changes; this only
restricts transitive versions.
PcmFrame is the canonical tap format (16-bit mono @ 24 kHz, 480 samples
per 20 ms frame — ARCHITECTURE.md). AudioSource/AudioSink are the seam
step 2 splices the tap client into (spec §3.3); EchoAudioPipe is the
slice-1 wiring of that seam. OpusDecoder/OpusEncoder wrap the opus
crate's libopus FFI with hot-path match-and-continue (no ? on the 20 ms
loop, spec §3.8); decode/encode return Option<PcmFrame>/Option<Vec<u8>>
so a dropped frame is logged + counted, never propagated to crash the
peer.
rutster-call-model is real-but-minimal (spec §5): the unifying leg
object the future API exposes. ChannelId is a Uuid newtype for
type-safety (the slice-1 worked example of the newtype pattern).
Channel is signaling-state only — media lives in rutster-media as a
leaf concern of the Channel, surfaced only when a second consumer needs
to observe it (spec §5.3). ChannelState matches the New→Connecting→
Connected→Closing→Closed flow from §5.4.
Workspace root, pinned toolchain, and the three stub crates whose only
job in slice 1 is to lock the ADR-0002 boundary shape. Each ships a
lib.rs module doc (what it will hold, why deferred, which spearhead step
fills it) and a crate_compiles test. Spec §2.2.
