voice-cat/PROGRESS.md

PROGRESS — VoiceCat

Living status. Update this file in the same commit as your work so the next agent picks up instantly. Newest status at the top.

• Date convention: ISO (YYYY-MM-DD).
• Statuses: [ ] not started · [~] in progress · [x] done.

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▶ Where we left off / next action

• Awaiting on-device verification: iOS stereo mic kills headphone/A2DP output — REAL root cause found & fixed (2026-06-20, on Windows; verify on Mac). All prior "fixes" (the 2026-06-19 entries below) targeted the Swift IOSAudioRouter on the false premise that "miniaudio does NOT touch AVAudioSession on iOS." It does. The core opened its miniaudio devices with ma_device_init(nullptr, ...); with a NULL context, miniaudio (0.11.25) runs an iOS "hack" (miniaudio.h ~44057) that picks a session category by device type, then ma_context_init__coreaudio (~36552) calls setCategory() + setActive() on every device open — capture → AVAudioSessionCategoryRecord with zero options. That wiped the .playAndRecord category, the mode, and .allowBluetoothA2DP/.mixWithOthers/.allowAirPlay that IOSAudioRouter had just configured → headphone/A2DP (and even wired) output died. The stereo presets broke worst because they depend on the A2DP output route the wipe removed. TeamTalk never hits this: its SDK opens RemoteIO/VPIO AudioUnits directly and leaves the session entirely to the app (UtilSound.swift); miniaudio insists on managing it.

  • Fix (core, cross-platform safe): AudioEngine now owns a ma_context built by make_context_config() with coreaudio.sessionCategory = ma_ios_session_category_none + noAudioSessionActivate/noAudioSessionDeactivate = MA_TRUE, and passes it to all ma_device_init calls (playback, capture, loopback) and to enumerate_devices's context. miniaudio now never touches AVAudioSession; the Swift IOSAudioRouter is the sole owner (session is already activated on connect in AppState.swift:authResult, before any device opens, so removing miniaudio's self-activation is safe). Context is lazily inited in start(), reused across restarts, uninited in ~AudioEngine. Files: core/src/audio/audio_engine.{h,cpp}.
  • TEMP diagnostics (remove after verification): AudioSessionManager.logSessionState(_:) logs category/mode/options/route; called after ensureSessionActive, on every route change, and on .streamStarted (right after the core opens its devices). On Mac, watch the log when joining voice with the Stereo Mic preset: category must stay …PlayAndRecord with allowBluetoothA2DP and the output route must remain the headphones/A2DP device — NOT flip to …Record. If confirmed, delete the logSessionState calls + method and the prior band-aid comments in IOSAudioRouter/audio_engine.cpp can be trimmed.
  • Verified on Windows: cmake --build --preset dev clean, ctest --preset dev 22/22 (21/21 prior + new test_dred_toggle). iOS build & on-device run still to be done by the user on the Mac.

• Planned (not started): External PCM feed/tap API (vc_stream_feed_pcm + vc_set_pcm_sink) (2026-06-19, plan written on Windows; implement on Mac). A public, documented API for driving audio streams with externally-provided PCM instead of (or in addition to) miniaudio's hardware device. Motivated by four concrete use cases — all in our roadmap — that the current "miniaudio owns the device" model can't serve:

  1. ReplayKit Broadcast Upload Extension (iOS SCREEN_AUDIO) — the extension is a separate process with a ~50 MB memory cap and can't link the full AudioEngine (ma_device, capture/playback threads). It needs to feed CMSampleBuffer audio (system app audio) into the encode path without any audio hardware. The current plan in docs/voice.md §9 says the extension links "a minimal slice of the core (Opus encode + media send only)" — a public feed-PCM API is that minimal slice. The extension links Opus + the feed entry point, no ma_device needed.
  2. ScreenCaptureKit (macOS SCREEN_AUDIO) — SCStream delivers CMSampleBuffer in a callback; convert to int16 and feed. No need to route through miniaudio's device layer. This is how macOS screen-audio actually gets implemented — today it does NOT work: VOICECAT_HAS_LOOPBACK is Windows-only (core/CMakeLists.txt:88-95), so on macOS AudioEngine::start_loopback_capture() hits the #else stub (audio_engine.cpp:647-649) and returns false. The macOS client's "Share Screen Audio" button (MainWindowController.swift:800-816) calls startStream(.screenAudio) which announces the stream to peers but captures zero audio — peers hear silence. The button is left in place (not touched per user request); it'll work once this API + a ScreenCaptureKit tap ship on Mac.
  3. Bots — music bot, TTS bot, radio relay, transcription bot. They create a SCREEN_AUDIO/AUX_DEVICE stream and feed synthesized or decoded PCM via the feed API. No audio hardware required — runs headless on a server. Today the only way to feed external PCM is vc_test_inject_capture (TEST-ONLY, name signals "don't ship this") or re-implementing Opus encode + AEAD + UDP framing yourself (~500 lines of duplicated crypto/codec code per consumer).
  4. Custom clients / accessibility — soundboard, DAW integration, TTS of incoming chat, recording/transcription of remote audio. Need either feed (send) or tap (receive) or both.

  What we already have (input half, gated as test-only): vc_test_inject_capture (stream_id, pcm, samples) (voicecat.h, client.cpp:1452) feeds raw int16 PCM into the encode pipeline via AudioEngine::inject_capture(kind, pcm, n). It works for any stream kind, supports multiple concurrent injection taps (one ring buffer per local kind), and goes through the full encode → AEAD → UDP path. The encode path already handles channels == 1 || 2 (proven by the WASAPI stereo loopback work, 2026-06-17 entry below). The only problems: it's marked TEST-ONLY in the header, the name signals "don't use this in production," and it hardcodes mono (no channels parameter).

  What's missing (output half): today decoded remote audio is mixed and pushed to the miniaudio playback device (on_playback). There's no way for an external consumer to intercept the decoded PCM of a specific remote stream — it all goes to the hardware device. A bot that wants to record, transcribe, or re-broadcast remote audio has no hook.

  Plan (API design — clean, append-only, no struct changes, ABI-stable):

  • vc_stream_feed_pcm — promote vc_test_inject_capture to a public, documented API and add a channels parameter:

    /* External PCM feed — replaces the hardware capture device for this stream. Caller
       provides interleaved int16 PCM at the stream's sample rate. The core frames it,
       encodes (Opus), seals (AEAD), and sends (UDP). Works for any stream kind
       (MIC/SCREEN_AUDIO/AUX_DEVICE). The stream must be started first (vc_stream_start);
       this just replaces the capture source. channels = 1 (mono) or 2 (stereo interleaved).
       Thread-safe; may be called from any thread including audio callbacks. */
    vc_result vc_stream_feed_pcm(vc_client* c, uint32_t stream_id,
                                 const int16_t* pcm, size_t samples_per_channel,
                                 uint32_t channels);
    

  • vc_set_pcm_sink — symmetric output side: receive decoded remote audio as int16 PCM instead of (or in addition to) the hardware playback device:

    /* External PCM tap — receive decoded, mixed remote audio as int16 PCM. The callback
       fires on the audio thread with the mixed output for a specific remote stream. Pass
       cb=NULL to disable (default: disabled, hardware playback only). When enabled, PCM is
       delivered to the sink AND the hardware device (dual output) so a bot can record
       without disabling local monitoring. user_id+stream_id identify the source stream.
       The callback MUST NOT block — copy what you need and return (same contract as
       vc_callbacks.on_event). */
    typedef void (*vc_pcm_sink_cb)(void* user, uint32_t user_id, uint32_t stream_id,
                                   const int16_t* pcm, size_t samples_per_channel,
                                   uint32_t channels, uint32_t sample_rate);
    vc_result vc_set_pcm_sink(vc_client* c, vc_pcm_sink_cb cb, void* user);
    

  • Core changes:
    • core/include/voicecat.h — add vc_pcm_sink_cb typedef + the two function declarations (append-only, after vc_test_inject_capture). Full doc comments on both (contract, thread-safety, lifetime, use cases).
    • core/src/voicecat.cpp — thin C trampolines → vc_client::stream_feed_pcm / set_pcm_sink.
    • core/src/core/client.{h,cpp} — stream_feed_pcm: validates stream_id, looks up the LocalStream's kind, calls audio_engine_.inject_capture(kind, pcm, n) (existing path) with the channel count forwarded. set_pcm_sink: stores the callback + user pointer; on_playback (or a new fan-out in the mixer) invokes it per remote stream alongside the existing hardware write. Keep vc_test_inject_capture as a deprecated alias calling stream_feed_pcm(..., channels=1) for source compatibility.
    • core/src/audio/audio_engine.{h,cpp} — inject_capture already exists per-kind; add a channels parameter to the ring-buffer write path (or a parallel stereo-aware variant). The encode path in client.cpp::on_capture_frame already handles channels==2 via the stereo encode branch — just plumb the value through. For the sink: add a pcm_sink_ member (callback + user); in on_playback after mixing, if the sink is set, copy the mixed PCM for the current stream and invoke the callback. The copy must stay off the RT-critical path — document the non-blocking contract.
  • Skeleton stub path: update client.cpp's #else (no-deps) stub section to add vc_stream_feed_pcm/vc_set_pcm_sink returning VC_ERR_NOT_IMPLEMENTED — keeps the skeleton preset green.
  • Swift VoiceCatCore: add feedPcm(streamId:pcm:samplesPerChannel:channels:) and setPcmSink(_:user:) (the Swift wrapper around vc_pcm_sink_cb — a @convention(c) closure + Unmanaged context, mirroring Callbacks.swift). Wraps both new ABI functions.
  • C# VoiceCat.Interop: add StreamFeedPcm(streamId, pcm, samples, channels) (with int16[] marshaling) and SetPcmSink (delegates via [UnmanagedCallersOnly] thunk, mirroring the event-callback pattern). Wraps both new ABI functions.
  • Tests:
    • tests/test_external_pcm.cpp (new) — test_feed_pcm_round_trip: two clients, A feeds a known mono sine wave via vc_stream_feed_pcm on a MIC stream, B receives via the normal decode path and asserts energy matches. test_feed_pcm_stereo: same with channels=2, assert L≠R end-to-end (mirrors the WASAPI loopback stereo test). test_pcm_sink: B sets a vc_pcm_sink_cb, A feeds PCM, assert the sink callback receives the decoded PCM with matching energy. All headless, no audio hardware.
    • clients/apple/Tests/VoiceCatCoreTests/ — Swift wrapper round-trip for feedPcm.
    • clients/windows/VoiceCat.Interop.Tests/ — C# wrapper round-trip.
  • Docs:
    • docs/architecture.md §4 — new subsection on external PCM feed/tap: the contract (caller provides interleaved int16 at the stream's sample rate; core frames/encodes/ seals/sends for feed; core decodes/mixes/delivers for sink; sink callback must not block), the use cases (ReplayKit, ScreenCaptureKit, bots, custom clients), and the relationship to vc_test_inject_capture (deprecated alias).
    • docs/voice.md §9 — update the iOS ReplayKit and macOS ScreenCaptureKit rows: both now consume vc_stream_feed_pcm instead of a "minimal slice of the core." Update the iOS detail bullets: the extension links Opus + vc_stream_feed_pcm (not a parallel media stack). Add a macOS ScreenCaptureKit note: convert CMSampleBuffer → int16, feed via vc_stream_feed_pcm — this is how macOS screen-audio actually ships.
    • docs/protocol.md — no protocol changes (the feed/sink are client-local; the wire format is identical whether PCM came from miniaudio or an external source). Note this explicitly.
    • docs/roadmap.md — add a milestone entry; update the iOS ReplayKit and macOS ScreenCaptureKit pending items to reference vc_stream_feed_pcm.
  • Implementation order:
    1. C ABI + core (voicecat.h, voicecat.cpp, client.{h,cpp}, audio_engine.{h,cpp}) + skeleton stub. Verify ctest --preset dev green.
    2. tests/test_external_pcm.cpp — the three behavior tests. Verify green.
    3. Swift VoiceCatCore wrapper + VoiceCatCoreTests round-trip.
    4. C# VoiceCat.Interop wrapper + VoiceCatClientSmokeTests round-trip.
    5. Docs (architecture.md, voice.md, protocol.md, roadmap.md, header comments).
    6. Then ReplayKit (iOS) and ScreenCaptureKit (macOS) become ~100-line consumers of this API instead of parallel media stacks.
  • Verification: ctest --preset dev green (3 new tests); swift test green; dotnet test green; xcodebuild (skeleton) green. The feed/sink tests are fully headless — no audio hardware, no simulator, no device — so they run in CI on every platform.
  • Files to touch:
    • Core C++: core/include/voicecat.h, core/src/voicecat.cpp, core/src/core/client.{h,cpp}, core/src/audio/audio_engine.{h,cpp}.
    • Tests: tests/test_external_pcm.cpp (new), tests/CMakeLists.txt.
    • Swift: clients/apple/Sources/VoiceCatCore/VoiceCatClient.swift, clients/apple/Sources/VoiceCatCore/Callbacks.swift, clients/apple/Tests/VoiceCatCoreTests/ExternalPcmTests.swift (new).
    • C#: clients/windows/VoiceCat.Interop/VoiceCatClient.cs, clients/windows/VoiceCat.Interop/NativeMethods.cs, clients/windows/VoiceCat.Interop.Tests/ExternalPcmTests.cs (new).
    • Docs: docs/architecture.md, docs/voice.md, docs/protocol.md, docs/roadmap.md.
  • ABI stability: append-only — two new functions + one new typedef, no existing structs/enums changed. vc_test_inject_capture stays as a deprecated alias for source compatibility. Treat as a deliberate, versioned ABI event per docs/protocol.md §8.
  • Relationship to the iOS audio routing plan: orthogonal. The iOS routing layer controls which hardware route miniaudio opens (AVAudioSession config in Swift). This plan is about bypassing miniaudio's hardware entirely (external PCM feed/tap). Both ship; they don't conflict. ReplayKit/ScreenCaptureKit consume this API; the iOS routing layer controls the mic path which still uses miniaudio's device.

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Recent completed work

All items below are [x] done; ctest --preset dev 21/21 on Windows after each.

• iOS A2DP + stereo root cause fix (2026-06-20): miniaudio's NULL-context ma_device_init was calling AVAudioSession setCategory(Record) on every device open, wiping the session config IOSAudioRouter had set. Fixed by sharing a ma_context with sessionCategory=none + noAudioSessionActivate/Deactivate=MA_TRUE — miniaudio never touches AVAudioSession; IOSAudioRouter is the sole owner. Files: audio_engine.{h,cpp}.

• iOS audio routing overhaul (2026-06-19): Full IOSAudioRouter singleton drives all AVAudioSession config before miniaudio opens devices. Fixed stereo mic polar-pattern setup (WWDC20 recipe: setPreferredInput + setInputDataSource + .stereo polar pattern + no setPreferredInputNumberOfChannels). Added vc_audio_restart ABI (full stop+reinit for close→reconfigure→reopen ordering). Added vc_set_capture_channels ABI (core stereo-mic support). AVAudioSession activated proactively on .authResult, not lazily on .streamStarted. Join/Leave Voice button added (parity with macOS). Channel-id sync fixed (mic button was permanently dimmed). iOS deployment target raised to 18.0.

• iOS SwiftUI client (2026-06-19): VoiceCatiOS.xcodeproj at clients/apple/iOS/. Full feature parity with macOS/Windows: saved server list (JSON + Keychain, App Group group.cat.voice.VoiceCat), TOFU, connect flow, channel tree, user list with context menus, chat, admin sheets, voice controls, settings. xcodebuild → BUILD SUCCEEDED.

• macOS AppKit client (2026-06-18): VoiceCatMac.xcodeproj at clients/apple/macOS/. Fixed compile errors (NSAccessibility call-site arg order, StreamSummary.id vs .streamId) and linker issues (OTHER_LDFLAGS = -lc++, ONLY_ACTIVE_ARCH = YES for Release). Debug + Release both BUILD SUCCEEDED.

• Swift VoiceCatCore package + XCFramework (2026-06-18): Shared Swift wrapper at clients/apple/. build-xcframework.sh merges libvoicecat.a + 107 vcpkg static deps into a fat .a via libtool -static. 6/6 Swift tests green (real server, mirrors C# Interop tests). Supports macOS-arm64 + iOS-arm64 + iOS-sim slices.

• macOS port validated (2026-06-18): 21/21 on macOS. Three cross-platform bugs fixed: missing <netdb.h> in POSIX test branch; SIGPIPE kills (added SIG_IGN); use-after-free of Asio kqueue reactor on server shutdown (fixed TcpAcceptor shutdown/connection-drain sequence).

• CMake preset cleanup (2026-06-18): m1-dev→dev, dev→skeleton, m2-dev dropped. New release, server-release (stripped), apple-dev/apple-ios/apple-ios-sim. Cross- platform triplet auto-resolved by cmake/voicecat-toolchain.cmake.

• Disconnect, keepalive & reaper (2026-06-18): Client sends Ping every 15 s; server reaper drops sessions after 45 s; UDP KEEPALIVE every 5 s keeps NAT alive. vc_disconnect sends graceful Disconnect proto. Stale-user LEFT broadcast on drop. PLC capped at ~2 s. Three new tests: test_disconnect_left, test_plc_cap, test_reaper_timeout.

• Stereo screen-audio loopback (2026-06-17): WASAPI loopback opens in channel's stereo/mono mode (was hardcoded mono). Real stereo flows end-to-end through loopback → encode → decode → mixer. New test_loopback_stereo_capture.

• Windows screen-audio UI wired (2026-06-17): btnScreenShareToggle in MainForm.cs. No core/proto/ABI changes — all the plumbing was already there. dotnet test 4/4 green.

• Bug fixes (2026-06-16 – 2026-06-17):

  • AEAD nonce desync in SFU relay — relay forwarded sender's seq verbatim; recipient nonce reconstruction used the wrong counter. Fixed by rewriting the outgoing seq field to the recipient's peek_send_counter().
  • Playout clock free-ran — playout_ts advanced even during VAD/PTT silence gaps, eventually dropping all frames as too-late. Fixed with resync in on_playback via JitterBuffer::peek_front_ts().
  • Stale users after disconnect — ConnSession::close() didn't broadcast UserEvent::LEFT before erasing. Fixed; PLC cap added as defense-in-depth.
  • "Randomly bumped to Lobby" — server excluded the actor from its own state-change broadcasts. Fixed: UserEvent::UPDATED now goes to all clients including the actor.
  • Silent playback after join — opus_decode received hardware callback frame count as max_samples instead of the Opus frame size. Fixed with a decode ring buffer.

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Milestones (see docs/roadmap.md for full detail)

• M0 — Scaffolding ✓ complete
• M1 — Control plane ✓ complete (2026-06-15)
• M2 — Voice, single stream ✓ complete (2026-06-16)
• M3 — Multi-stream & per-channel tuning ✓ complete (2026-06-16)
• M4 — Native clients — Windows WinForms ✓ (2026-06-17); macOS AppKit ✓ (2026-06-18); iOS SwiftUI ✓ (2026-06-19)
• [~] M5 — Moderation, polish, beyond (perms, bans, DRED; then file transfer, E2EE, …)

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M0 — Scaffolding ✓

Repo layout (core/ server/ tools/ clients/ tests/), CMake + vcpkg manifest, C ABI header (voicecat.h), proto source of truth, core stubs for all six subsystems, voicecat-server + vccli skeletons, smoke CTest, .clang-format/.gitattributes/.gitignore.

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M1 — Control plane ✓ (completed 2026-06-15)

Exit criterion: test_m1_integration — two clients authenticate over TLS 1.3 (guest + Argon2id), exchange channel + private text. ~1 s.

FrameCodec, TlsContext (mbedTLS 1.3, ECDSA-P256 self-signed, TOFU pins TLS leaf-cert SHA-256), WorkerPool, Database (SQLite + Argon2id), ServerIdentityManager, ConnSession state machine, SessionRegistry, vc_client full M1 C ABI, voicecat-admin CLI, dual-stack TcpAcceptor. Key bug fixed: send_frame double-framing — encode_envelope was pre-framing the protobuf; fixed by passing raw protobuf bytes.

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M2 — Voice, single stream ✓ (completed 2026-06-16)

Exit criterion: test_m2_voice + test_voice_client_abi — two headless clients auth, bind UDP, 50 Opus frames relayed + re-encrypted by SFU, B receives ≥25 and decrypts. ~4 s.

14-byte UDP voice header, SodiumMediaCrypto (ChaCha20-Poly1305 + 64-bit anti-replay), OpusEncoder/OpusDecoder (FEC, PLC), UdpMediaChannel, JitterBuffer, AudioEngine (miniaudio), MediaRelay SFU. Key bug fixed: on_playback passed hardware callback frame count as opus_decode max_samples; fixed with a per-stream decode ring buffer.

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M3 — Multi-stream & per-channel tuning ✓ (completed 2026-06-16)

Exit criterion: test_m3_multistream — client A runs two concurrent streams (MIC + SCREEN_AUDIO); B sees both; per-stream gain/mute/NR independent; effective Opus config matches channel's server-enforced settings. ~2.4 s.

Fixed server stream_id counter bug (always wrote 1). Per-channel AudioConfig populated (Lobby: mono/24kbps/VOIP + DTX; Music Room: stereo/128kbps/AUDIO). LocalStream map, pending_announce_kind_, run_talk_timer(), thread-join race in teardown_voice() fixed. New C ABI: vc_get_stream_audio_config, vc_test_inject_capture.

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Post-M3 follow-up ✓ (completed 2026-06-16)

• Device enumeration — vc_list_devices/vc_set_input_device; opaque hex device ids; vc_free_device_list now frees. Works pre-connect.
• VAD/PTT gate — EnergyVadProcessor (RMS threshold ~0.025, 300 ms hang-time); vc_set_input_mode/vc_set_push_to_talk; MIC-only (SCREEN_AUDIO/AUX_DEVICE bypass).
• True stereo playback — playback_channels=2; stereo decoded L→L R→R in mixer; mono upmixed L=R; hardware fallback to mono on failure.
• WASAPI loopback — loopback_device_ with ma_device_type_loopback; VOICECAT_HAS_LOOPBACK macro (Windows-only). vccli --share-screen-audio.

Known deferred (still open): AEC/NS/AGC (no working Windows/MSVC WebRTC APM build); process-specific WASAPI loopback; RT-thread rule violation in on_capture_frame (mutex lock on audio callback thread — pre-existing, needs lock-free ring-buffer refactor).

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M4 — Native clients ✓ (completed 2026-06-17 – 2026-06-19)

Exit criterion: ctest --preset dev 21/21 green; dotnet build 0 warnings; xcodebuild BUILD SUCCEEDED (macOS + iOS); manually verified: connect, TOFU, channel tree, join, voice, text, device pickers, level meter on each platform.

New C ABI (additive): vc_list_channels/vc_list_users/vc_list_user_streams, vc_join_channel, VC_EVENT_SERVER_IDENTITY + vc_confirm_server_identity, vc_config::tofu_store_path, VC_INPUT_ALWAYS_ON, vc_set_vad_threshold, vc_audio_suspend/vc_audio_resume, vc_audio_restart, vc_set_capture_channels.

Windows (clients/windows/): VoiceCat.Interop (P/Invoke, [UnmanagedCallersOnly]), VoiceCat.App (ConnectDialog, ServerIdentityDialog, MainForm with full M5 moderation UI, PerUserTuningDialog, PttKeyCaptureDialog), VoiceCat.Interop.Tests. PTT is focus-scoped.

macOS (clients/apple/macOS/VoiceCatMac.xcodeproj): NSOutlineView channel tree, NSTableView user list, NSTextView chat, voice controls, full VoiceOver accessibility, admin menu, 17 Swift source files. build-xcframework.sh produces VoiceCatCore.xcframework.

iOS (clients/apple/iOS/VoiceCatiOS.xcodeproj): SwiftUI, NavigationSplitView/TabView, OutlineGroup channel tree, IOSAudioRouter AVAudioSession driver, 24 Swift source files, iOS 18.0 deployment target. App Group group.cat.voice.VoiceCat for Keychain sharing.

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M5 — Moderation, polish, and beyond [~] (in progress 2026-06-17)

Exit criterion: four ABI-level tests green (test_m5_permissions, test_m5_kick_ban_move_mute, test_m5_admin_accounts, test_m5_channel_crud); vccli can drive all moderation/admin/channel operations against a live server.

• Server-side moderation & permissions — per-session Permissions, kick/ban/move/ server-mute, channel CRUD, DB schema v2 (channels, bans), BLAKE2b channel passwords.
• C ABI — vc_kick_user, vc_ban_user, vc_set_permission, vc_set_server_mute, vc_move_user, vc_create_channel, vc_edit_channel, vc_delete_channel, vc_create_account, vc_reset_password, vc_delete_account, vc_list_accounts, vc_get_permissions; events VC_EVENT_GENERIC_RESULT, VC_EVENT_ACCOUNT_LIST.
• Four M5 tests passing — ctest --preset dev 21/21.
• vccli M5 flags: --kick, --ban, --move, --server-mute/-unmute/-deafen/ -undeafen, --set-permission, channel CRUD, account CRUD, --username/--password.
• All three client UIs (Windows WinForms, macOS AppKit, iOS SwiftUI) expose the full M5 moderation and admin surface.
• Docs — docs/protocol.md, docs/security.md kept in sync.
• DRED/audio-quality polish — done (2026-06-20). bool dred added to AudioConfig proto (field 11) and vc_audio_config C ABI. Encoder: OPUS_SET_DRED_DURATION(2) when enabled (20 ms of ML redundancy per packet). Decoder: OpusDREDDecoder + per-stream OpusDRED scratch pre-allocated; JitterBuffer::try_copy_front_payload peeks at the next buffered packet on every PLC step; if DRED data is present, opus_decoder_dred_decode reconstructs the lost frame — otherwise falls back to standard PLC. New test: test_dred_toggle (ctest 22/22). Files: voicecat.proto, voicecat.h, opus_codec.{h,cpp}, audio_engine.{h,cpp}, client.cpp, session.{h,cpp}.
• DRED toggle in client UIs — expose the dred flag in all three channel-config UIs so admins can enable it per channel. Windows: ChannelEditForm / vc_channel_info.audio.dred checkbox. macOS AppKit: channel-edit sheet. iOS SwiftUI: channel-edit form. All three UIs already have full channel CRUD wired; this is an additive checkbox on the existing audio-config section. (Core/protocol/ABI all done — this is UI-only work.)
• macOS ScreenCaptureKit screen-audio — startStream(.screenAudio) in macOS client announces the stream but start_loopback_capture() returns false (no VOICECAT_HAS_LOOPBACK on macOS). Implement via vc_stream_feed_pcm + SCStream once the feed API ships.
• iOS ReplayKit Broadcast Extension (VoiceCatBroadcast) — separate Xcode target, App Group credential sharing, SampleHandler.swift. Implement via vc_stream_feed_pcm.
• External PCM feed/tap API (vc_stream_feed_pcm + vc_set_pcm_sink) — see full plan in "Where we left off" above.

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Decisions log

All architecture/scope decisions are settled and recorded in docs/roadmap.md §2 "Resolved decisions" and reflected across docs/. If you make a new decision, record it there and link it here.

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How to update this file

1. Check off tasks as you complete them; flip a milestone to [x] only when its exit criterion test passes.
2. Keep the "Where we left off / next action" block at the top accurate — it's the first thing the next agent reads.
3. When you start a milestone, copy its task list from docs/roadmap.md into a section here.