feat: add voice mode support via mic passthrough to container

Enables Claude Code's /voice command inside Docker containers by
capturing microphone audio in the Tauri webview and streaming it
into the container via a FIFO pipe.

Container: fake rec/arecord shims read PCM from a FIFO instead of
a real mic. Audio bridge exec writes PCM from Tauri into the FIFO.
Frontend: getUserMedia() + AudioWorklet captures 16kHz mono PCM
and streams it to the container via invoke("send_audio_data").
UI: "Mic Off/On" toggle button in the terminal view.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/public/audio-capture-processor.js

@@ -0,0 +1,17 @@
+class AudioCaptureProcessor extends AudioWorkletProcessor {
+  process(inputs, outputs, parameters) {
+    const input = inputs[0];
+    if (input && input.length > 0 && input[0].length > 0) {
+      const samples = input[0]; // Float32Array, mono channel
+      const int16 = new Int16Array(samples.length);
+      for (let i = 0; i < samples.length; i++) {
+        const s = Math.max(-1, Math.min(1, samples[i]));
+        int16[i] = s < 0 ? s * 0x8000 : s * 0x7FFF;
+      }
+      this.port.postMessage(int16.buffer, [int16.buffer]);
+    }
+    return true;
+  }
+}
+
+registerProcessor('audio-capture-processor', AudioCaptureProcessor);

app/src-tauri/src/commands/terminal_commands.rs

@@ -133,6 +133,10 @@ pub async fn close_terminal_session(
     session_id: String,
     state: State<'_, AppState>,
 ) -> Result<(), String> {
+    // Close audio bridge if it exists
+    let audio_session_id = format!("audio-{}", session_id);
+    state.exec_manager.close_session(&audio_session_id).await;
+    // Close terminal session
     state.exec_manager.close_session(&session_id).await;
     Ok(())
 }
@@ -156,3 +160,53 @@ pub async fn paste_image_to_terminal(
         .write_file_to_container(&container_id, &file_name, &image_data)
         .await
 }
+
+#[tauri::command]
+pub async fn start_audio_bridge(
+    session_id: String,
+    state: State<'_, AppState>,
+) -> Result<(), String> {
+    // Get container_id from the terminal session
+    let container_id = state.exec_manager.get_container_id(&session_id).await?;
+
+    // Create audio bridge exec session with ID "audio-{session_id}"
+    // The loop handles reconnection when the FIFO reader (fake rec) is killed and restarted
+    let audio_session_id = format!("audio-{}", session_id);
+    let cmd = vec![
+        "bash".to_string(),
+        "-c".to_string(),
+        "FIFO=/tmp/triple-c-audio-input; [ -p \"$FIFO\" ] || mkfifo \"$FIFO\"; trap '' PIPE; while true; do cat > \"$FIFO\" 2>/dev/null; sleep 0.1; done".to_string(),
+    ];
+
+    state
+        .exec_manager
+        .create_session_with_tty(
+            &container_id,
+            &audio_session_id,
+            cmd,
+            false,
+            |_data| { /* ignore output from the audio bridge */ },
+            Box::new(|| { /* no exit handler needed */ }),
+        )
+        .await
+}
+
+#[tauri::command]
+pub async fn send_audio_data(
+    session_id: String,
+    data: Vec<u8>,
+    state: State<'_, AppState>,
+) -> Result<(), String> {
+    let audio_session_id = format!("audio-{}", session_id);
+    state.exec_manager.send_input(&audio_session_id, data).await
+}
+
+#[tauri::command]
+pub async fn stop_audio_bridge(
+    session_id: String,
+    state: State<'_, AppState>,
+) -> Result<(), String> {
+    let audio_session_id = format!("audio-{}", session_id);
+    state.exec_manager.close_session(&audio_session_id).await;
+    Ok(())
+}

app/src-tauri/src/docker/exec.rs

@@ -60,6 +60,22 @@ impl ExecSessionManager {
         on_output: F,
         on_exit: Box<dyn FnOnce() + Send>,
     ) -> Result<(), String>
+    where
+        F: Fn(Vec<u8>) + Send + 'static,
+    {
+        self.create_session_with_tty(container_id, session_id, cmd, true, on_output, on_exit)
+            .await
+    }
+
+    pub async fn create_session_with_tty<F>(
+        &self,
+        container_id: &str,
+        session_id: &str,
+        cmd: Vec<String>,
+        tty: bool,
+        on_output: F,
+        on_exit: Box<dyn FnOnce() + Send>,
+    ) -> Result<(), String>
     where
         F: Fn(Vec<u8>) + Send + 'static,
     {
@@ -72,7 +88,7 @@ impl ExecSessionManager {
                     attach_stdin: Some(true),
                     attach_stdout: Some(true),
                     attach_stderr: Some(true),
-                    tty: Some(true),
+                    tty: Some(tty),
                     cmd: Some(cmd),
                     user: Some("claude".to_string()),
                     working_dir: Some("/workspace".to_string()),

app/src-tauri/src/lib.rs

@@ -101,6 +101,9 @@ pub fn run() {
             commands::terminal_commands::terminal_resize,
             commands::terminal_commands::close_terminal_session,
             commands::terminal_commands::paste_image_to_terminal,
+            commands::terminal_commands::start_audio_bridge,
+            commands::terminal_commands::send_audio_data,
+            commands::terminal_commands::stop_audio_bridge,
             // MCP
             commands::mcp_commands::list_mcp_servers,
             commands::mcp_commands::add_mcp_server,

app/src/components/terminal/TerminalView.tsx

@@ -6,6 +6,7 @@ import { WebLinksAddon } from "@xterm/addon-web-links";
 import { openUrl } from "@tauri-apps/plugin-opener";
 import "@xterm/xterm/css/xterm.css";
 import { useTerminal } from "../../hooks/useTerminal";
+import { useVoice } from "../../hooks/useVoice";
 import { UrlDetector } from "../../lib/urlDetector";
 import UrlToast from "./UrlToast";
 
@@ -23,6 +24,8 @@ export default function TerminalView({ sessionId, active }: Props) {
   const detectorRef = useRef<UrlDetector | null>(null);
   const { sendInput, pasteImage, resize, onOutput, onExit } = useTerminal();
 
+  const voice = useVoice(sessionId);
+
   const [detectedUrl, setDetectedUrl] = useState<string | null>(null);
   const [imagePasteMsg, setImagePasteMsg] = useState<string | null>(null);
   const [isAtBottom, setIsAtBottom] = useState(true);
@@ -200,6 +203,7 @@ export default function TerminalView({ sessionId, active }: Props) {
       try { webglRef.current?.dispose(); } catch { /* may already be disposed */ }
       webglRef.current = null;
       term.dispose();
+      voice.stop();
     };
   }, [sessionId]); // eslint-disable-line react-hooks/exhaustive-deps
 
@@ -284,6 +288,32 @@ export default function TerminalView({ sessionId, active }: Props) {
           {imagePasteMsg}
         </div>
       )}
+      <button
+        onClick={voice.toggle}
+        title={
+          voice.state === "active"
+            ? "Voice active — click to stop"
+            : voice.error
+              ? `Voice error: ${voice.error}`
+              : "Enable voice input for /voice mode"
+        }
+        className={`absolute bottom-4 left-4 z-50 px-3 py-1.5 rounded-md text-xs font-medium border shadow-lg transition-colors cursor-pointer ${
+          voice.state === "active"
+            ? "bg-[#1a3a2a] text-[#3fb950] border-[#238636] hover:bg-[#243b2a]"
+            : voice.state === "starting"
+              ? "bg-[#1f2937] text-[#d29922] border-[#30363d] opacity-75"
+              : voice.state === "error"
+                ? "bg-[#3a1a1a] text-[#ff7b72] border-[#da3633] hover:bg-[#4a2020]"
+                : "bg-[#1f2937] text-[#b1bac4] border-[#30363d] hover:bg-[#2d3748] hover:text-[#e6edf3]"
+        }`}
+        disabled={voice.state === "starting"}
+      >
+        {voice.state === "active"
+          ? "Mic On"
+          : voice.state === "starting"
+            ? "Mic..."
+            : "Mic Off"}
+      </button>
       {!isAtBottom && (
         <button
           onClick={handleScrollToBottom}

app/src/hooks/useVoice.ts

@@ -0,0 +1,98 @@
+import { useCallback, useRef, useState } from "react";
+import * as commands from "../lib/tauri-commands";
+
+type VoiceState = "inactive" | "starting" | "active" | "error";
+
+export function useVoice(sessionId: string) {
+  const [state, setState] = useState<VoiceState>("inactive");
+  const [error, setError] = useState<string | null>(null);
+
+  const audioContextRef = useRef<AudioContext | null>(null);
+  const streamRef = useRef<MediaStream | null>(null);
+  const workletRef = useRef<AudioWorkletNode | null>(null);
+
+  const start = useCallback(async () => {
+    if (state === "active" || state === "starting") return;
+    setState("starting");
+    setError(null);
+
+    try {
+      // 1. Start the audio bridge in the container (creates FIFO writer)
+      await commands.startAudioBridge(sessionId);
+
+      // 2. Get microphone access
+      const stream = await navigator.mediaDevices.getUserMedia({
+        audio: {
+          channelCount: 1,
+          echoCancellation: true,
+          noiseSuppression: true,
+          autoGainControl: true,
+        },
+      });
+      streamRef.current = stream;
+
+      // 3. Create AudioContext at 16kHz (browser handles resampling)
+      const audioContext = new AudioContext({ sampleRate: 16000 });
+      audioContextRef.current = audioContext;
+
+      // 4. Load AudioWorklet processor
+      await audioContext.audioWorklet.addModule("/audio-capture-processor.js");
+
+      // 5. Connect: mic → worklet → (silent) destination
+      const source = audioContext.createMediaStreamSource(stream);
+      const processor = new AudioWorkletNode(audioContext, "audio-capture-processor");
+      workletRef.current = processor;
+
+      // 6. Handle PCM chunks from the worklet
+      processor.port.onmessage = (event: MessageEvent<ArrayBuffer>) => {
+        const bytes = Array.from(new Uint8Array(event.data));
+        commands.sendAudioData(sessionId, bytes).catch(() => {
+          // Audio bridge may have been closed — ignore send errors
+        });
+      };
+
+      source.connect(processor);
+      processor.connect(audioContext.destination);
+
+      setState("active");
+    } catch (e) {
+      const msg = e instanceof Error ? e.message : String(e);
+      setError(msg);
+      setState("error");
+      // Clean up on failure
+      await commands.stopAudioBridge(sessionId).catch(() => {});
+    }
+  }, [sessionId, state]);
+
+  const stop = useCallback(async () => {
+    // Tear down audio pipeline
+    workletRef.current?.disconnect();
+    workletRef.current = null;
+
+    if (audioContextRef.current) {
+      await audioContextRef.current.close().catch(() => {});
+      audioContextRef.current = null;
+    }
+
+    if (streamRef.current) {
+      streamRef.current.getTracks().forEach((t) => t.stop());
+      streamRef.current = null;
+    }
+
+    // Stop the container-side audio bridge
+    await commands.stopAudioBridge(sessionId).catch(() => {});
+
+    setState("inactive");
+    setError(null);
+  }, [sessionId]);
+
+  const toggle = useCallback(async () => {
+    if (state === "active") {
+      await stop();
+    } else {
+      await start();
+    }
+  }, [state, start, stop]);
+
+  return { state, error, start, stop, toggle };
+}

app/src/lib/tauri-commands.ts

@@ -49,6 +49,12 @@ export const closeTerminalSession = (sessionId: string) =>
   invoke<void>("close_terminal_session", { sessionId });
 export const pasteImageToTerminal = (sessionId: string, imageData: number[]) =>
   invoke<string>("paste_image_to_terminal", { sessionId, imageData });
+export const startAudioBridge = (sessionId: string) =>
+  invoke<void>("start_audio_bridge", { sessionId });
+export const sendAudioData = (sessionId: string, data: number[]) =>
+  invoke<void>("send_audio_data", { sessionId, data });
+export const stopAudioBridge = (sessionId: string) =>
+  invoke<void>("stop_audio_bridge", { sessionId });
 
 // MCP Servers
 export const listMcpServers = () => invoke<McpServer[]>("list_mcp_servers");

container/Dockerfile

@@ -111,6 +111,14 @@ RUN chmod +x /usr/local/bin/osc52-clipboard \
     && ln -sf /usr/local/bin/osc52-clipboard /usr/local/bin/xsel \
     && ln -sf /usr/local/bin/osc52-clipboard /usr/local/bin/pbcopy
 
+# ── Audio capture shim (voice mode) ────────────────────────────────────────
+# Provides fake rec/arecord that read PCM from a FIFO instead of a real mic,
+# allowing Claude Code voice mode to work inside the container.
+COPY audio-shim /usr/local/bin/audio-shim
+RUN chmod +x /usr/local/bin/audio-shim \
+    && ln -sf /usr/local/bin/audio-shim /usr/local/bin/rec \
+    && ln -sf /usr/local/bin/audio-shim /usr/local/bin/arecord
+
 COPY entrypoint.sh /usr/local/bin/entrypoint.sh
 RUN chmod +x /usr/local/bin/entrypoint.sh
 COPY triple-c-scheduler /usr/local/bin/triple-c-scheduler

container/audio-shim

@@ -0,0 +1,16 @@
+#!/bin/bash
+# Audio capture shim for Triple-C voice mode.
+# Claude Code spawns `rec` or `arecord` to capture mic audio.
+# Inside Docker there is no mic, so this shim reads PCM data from a
+# FIFO that the Tauri host app writes to, and outputs it on stdout.
+
+FIFO=/tmp/triple-c-audio-input
+
+# Create the FIFO if it doesn't already exist
+[ -p "$FIFO" ] || mkfifo "$FIFO" 2>/dev/null
+
+# Clean exit on SIGTERM (Claude Code sends this when recording stops)
+trap 'exit 0' TERM INT
+
+# Stream PCM from the FIFO to stdout until we get a signal or EOF
+cat "$FIFO"