diff --git a/examples/offline_inference/moss_tts_nano/README.md b/examples/offline_inference/moss_tts_nano/README.md
new file mode 100644
index 000000000..f7ace3b86
--- /dev/null
+++ b/examples/offline_inference/moss_tts_nano/README.md
@@ -0,0 +1,99 @@
+# MOSS-TTS-Nano Offline Inference
+
+## Overview
+
+Single-stage offline TTS pipeline using the 0.1B MOSS-TTS-Nano AR LM and MOSS-Audio-Tokenizer-Nano codec. Outputs 48 kHz stereo WAV.
+
+## Quick Start
+
+```bash
+python end2end.py --text "Hello, this is MOSS-TTS-Nano."
+```
+
+The first run downloads `OpenMOSS-Team/MOSS-TTS-Nano` and `OpenMOSS-Team/MOSS-Audio-Tokenizer-Nano` from Hugging Face.
+
+## Usage
+
+```
+python end2end.py [OPTIONS]
+
+Options:
+ --text TEXT Text to synthesize (default: "Hello, this is MOSS-TTS-Nano speaking.")
+ --voice VOICE Built-in voice preset (default: Junhao). See voice table below.
+ --mode MODE voice_clone (default) or continuation
+ --prompt-audio PATH Reference WAV/MP3 for custom voice cloning
+ --prompt-text TEXT Reference transcript (continuation mode)
+ --max-new-frames N Max AR frames, default 375 (~14 s audio)
+ --seed INT Random seed for reproducibility
+ --audio-temperature F Audio sampling temperature (default: 0.8)
+ --audio-top-k N Audio top-k sampling (default: 25)
+ --audio-top-p F Audio top-p sampling (default: 0.95)
+ --text-temperature F Text layer temperature (default: 1.0)
+ --batch Run a built-in batch of diverse samples (ZH/EN/FR)
+ --output-dir DIR Directory for WAV outputs (default: /tmp/moss_tts_nano_output)
+ --stage-config PATH Path to stage config YAML
+ --stage-init-timeout INT Timeout in seconds for stage init (default: 120)
+```
+
+## Examples
+
+```bash
+# Built-in Chinese voice
+python end2end.py --text "你好,这是MOSS-TTS-Nano的语音合成演示。" --voice Junhao
+
+# Built-in English voice
+python end2end.py --text "Hello from MOSS-TTS-Nano." --voice Ava
+
+# Custom voice clone
+python end2end.py \
+ --text "Hello, this is a cloned voice." \
+ --prompt-audio /path/to/reference.wav \
+ --prompt-text "Exact transcript of the reference audio."
+
+# Batch synthesis (ZH/EN/FR)
+python end2end.py --batch --output-dir /tmp/batch_output
+
+# Reproducible output
+python end2end.py --text "Deterministic test." --seed 42
+```
+
+## Built-in Voice Presets
+
+| Voice | Language |
+|-------|----------|
+| `Junhao` | ZH |
+| `Zhiming` | ZH |
+| `Weiguo` | ZH |
+| `Xiaoyu` | ZH |
+| `Yuewen` | ZH |
+| `Lingyu` | ZH |
+| `Ava` | EN |
+| `Bella` | EN |
+| `Adam` | EN |
+| `Nathan` | EN |
+| `Sakura` | JA |
+| `Yui` | JA |
+| `Aoi` | JA |
+| `Hina` | JA |
+| `Mei` | JA |
+
+## Stage Config
+
+The stage config is at `vllm_omni/model_executor/stage_configs/moss_tts_nano.yaml`. Key settings:
+
+```yaml
+engine_args:
+ gpu_memory_utilization: 0.3 # ~2 GB VRAM; increase for faster init
+ max_num_seqs: 4 # concurrent requests
+ max_model_len: 4096
+```
+
+## Output Format
+
+WAV files, 48 kHz, stereo (2-channel). The codec interleaves stereo as `[L, R, L, R, ...]` in the flat tensor returned by the model.
+
+## Troubleshooting
+
+- **`libnvrtc.so.13: cannot open shared object file`**: torchaudio 2.10+ torchcodec backend requires NVRTC. The model patches `torchaudio.load/save` automatically at load time to fall back to soundfile.
+- **`flash_attn not installed`**: The model falls back to `sdpa` attention automatically.
+- **Empty audio**: Check that `--text` is non-empty and the model loaded successfully (look for "MOSS-TTS-Nano LM loaded" in logs).
diff --git a/examples/online_serving/moss_tts_nano/README.md b/examples/online_serving/moss_tts_nano/README.md
new file mode 100644
index 000000000..371bde789
--- /dev/null
+++ b/examples/online_serving/moss_tts_nano/README.md
@@ -0,0 +1,159 @@
+# MOSS-TTS-Nano
+
+## Model
+
+| Model | Description |
+|-------|-------------|
+| `OpenMOSS-Team/MOSS-TTS-Nano` | 0.1B AR LM + MOSS-Audio-Tokenizer-Nano codec, 48 kHz stereo, ZH/EN/JA |
+
+## Gradio Demo
+
+An interactive Gradio demo is available with multilingual voice presets, custom voice cloning, and streaming support.
+
+```bash
+# Option 1: Launch server + Gradio together
+./run_gradio_demo.sh
+
+# Option 2: If server is already running
+python gradio_demo.py --api-base http://localhost:8091
+```
+
+Then open http://localhost:7860 in your browser.
+
+Features:
+
+- 15 built-in voice presets (6 ZH · 4 EN · 5 JA)
+- Custom voice cloning from uploaded reference audio
+- Streaming mode (progressive PCM playback)
+
+## Launch the Server
+
+```bash
+vllm-omni serve OpenMOSS-Team/MOSS-TTS-Nano \
+ --stage-configs-path vllm_omni/model_executor/stage_configs/moss_tts_nano.yaml \
+ --omni \
+ --port 8091 \
+ --trust-remote-code \
+ --enforce-eager
+```
+
+Or use the convenience script:
+
+```bash
+./run_server.sh
+```
+
+## Send TTS Request
+
+### Using curl
+
+```bash
+# Built-in voice preset
+curl -X POST http://localhost:8091/v1/audio/speech \
+ -H "Content-Type: application/json" \
+ -d '{
+ "input": "你好,这是语音合成测试。",
+ "voice": "Junhao",
+ "response_format": "wav"
+ }' --output output.wav
+
+# English preset
+curl -X POST http://localhost:8091/v1/audio/speech \
+ -H "Content-Type: application/json" \
+ -d '{
+ "input": "Hello, this is MOSS-TTS-Nano.",
+ "voice": "Ava",
+ "response_format": "wav"
+ }' --output output_en.wav
+```
+
+### Custom Voice Cloning
+
+Provide a reference audio (base64 data URL) and its transcript:
+
+```bash
+REF_AUDIO=$(base64 -w 0 /path/to/reference.wav)
+curl -X POST http://localhost:8091/v1/audio/speech \
+ -H "Content-Type: application/json" \
+ -d "{
+ \"input\": \"Hello, this is a cloned voice.\",
+ \"voice\": \"Junhao\",
+ \"ref_audio\": \"data:audio/wav;base64,${REF_AUDIO}\",
+ \"ref_text\": \"Exact transcript of the reference audio.\"
+ }" --output cloned.wav
+```
+
+### Using Python
+
+```python
+import httpx
+
+response = httpx.post(
+ "http://localhost:8091/v1/audio/speech",
+ json={
+ "input": "你好,这是语音合成测试。",
+ "voice": "Junhao",
+ "response_format": "wav",
+ },
+ timeout=300.0,
+)
+
+with open("output.wav", "wb") as f:
+ f.write(response.content)
+```
+
+### Streaming
+
+```bash
+curl -X POST http://localhost:8091/v1/audio/speech \
+ -H "Content-Type: application/json" \
+ -d '{
+ "input": "Hello, streaming output from MOSS-TTS-Nano.",
+ "voice": "Ava",
+ "stream": true,
+ "response_format": "pcm"
+ }' --no-buffer | play -t raw -r 48000 -e signed -b 16 -c 2 -
+```
+
+**Note:** MOSS-TTS-Nano outputs at 48 kHz stereo (2-channel).
+
+## API Parameters
+
+MOSS-TTS-Nano uses the standard `/v1/audio/speech` endpoint.
+
+| Parameter | Type | Default | Description |
+|-----------|------|---------|-------------|
+| `input` | string | **required** | Text to synthesize (ZH / EN / JA) |
+| `voice` | string | `"Junhao"` | Built-in voice name (see table below) |
+| `response_format` | string | `"wav"` | Audio format: wav, mp3, flac, pcm |
+| `ref_audio` | string | null | Base64 data URL for custom voice cloning |
+| `ref_text` | string | null | Transcript of reference audio (required when `ref_audio` is set) |
+| `stream` | bool | false | Stream raw PCM chunks |
+| `max_new_tokens` | int | 4096 | Maximum tokens to generate |
+
+## Built-in Voice Presets
+
+| Voice | Language | Description |
+|-------|----------|-------------|
+| `Junhao` | ZH | Male, standard Mandarin |
+| `Zhiming` | ZH | Male |
+| `Weiguo` | ZH | Male |
+| `Xiaoyu` | ZH | Female |
+| `Yuewen` | ZH | Female |
+| `Lingyu` | ZH | Female |
+| `Ava` | EN | Female, American English |
+| `Bella` | EN | Female |
+| `Adam` | EN | Male |
+| `Nathan` | EN | Male |
+| `Sakura` | JA | Female |
+| `Yui` | JA | Female |
+| `Aoi` | JA | Female |
+| `Hina` | JA | Female |
+| `Mei` | JA | Female |
+
+## Troubleshooting
+
+1. **`libnvrtc.so.13: cannot open shared object file`**: torchaudio 2.10+ defaults to torchcodec which requires NVRTC. vLLM-Omni patches this automatically at model load time to use soundfile instead.
+2. **Connection refused**: Ensure the server is running on the correct port.
+3. **Flashinfer version mismatch**: Set `FLASHINFER_DISABLE_VERSION_CHECK=1` if you see version warnings.
+4. **Out of memory**: The default `gpu_memory_utilization=0.3` is conservative. Increase it in the stage config if you have more VRAM available.
diff --git a/examples/online_serving/moss_tts_nano/gradio_demo.py b/examples/online_serving/moss_tts_nano/gradio_demo.py
new file mode 100644
index 000000000..6eeb8d4c0
--- /dev/null
+++ b/examples/online_serving/moss_tts_nano/gradio_demo.py
@@ -0,0 +1,693 @@
+"""Gradio demo for MOSS-TTS-Nano with gapless streaming audio playback.
+
+Uses a custom AudioWorklet-based player (adapted from the Qwen3-TTS demo)
+for gap-free streaming. Audio is streamed from the vLLM-Omni server
+through a same-origin proxy and played via the Web Audio API's AudioWorklet.
+
+MOSS-TTS-Nano outputs 48 kHz stereo (2-channel interleaved L,R,L,R,...).
+The AudioWorklet downmixes stereo to mono during playback.
+
+Also supports non-streaming mode (full audio download) via gr.Audio.
+
+Usage:
+ # Start the server first (see run_server.sh), then:
+ python gradio_demo.py --api-base http://localhost:8091
+
+ # Or use run_gradio_demo.sh to start both server and demo together.
+"""
+
+from __future__ import annotations
+
+import argparse
+import base64
+import io
+import json
+import logging
+
+try:
+ import gradio as gr
+except ImportError:
+ raise ImportError(
+ "gradio is required to run this demo. Install it with: pip install 'vllm-omni[demo]'"
+ ) from None
+
+import httpx
+import numpy as np
+import soundfile as sf
+from fastapi import FastAPI, Request
+from fastapi.responses import Response, StreamingResponse
+
+logger = logging.getLogger(__name__)
+
+# MOSS-TTS-Nano outputs 48 kHz stereo (2-channel interleaved).
+PCM_SAMPLE_RATE = 48000
+PCM_CHANNELS = 2
+DEFAULT_API_BASE = "http://localhost:8091"
+
+# Built-in voice presets (matches the MOSS-TTS-Nano GitHub repo assets/)
+VOICE_PRESETS = {
+ # Chinese
+ "Junhao (ZH)": "Junhao",
+ "Zhiming (ZH)": "Zhiming",
+ "Weiguo (ZH)": "Weiguo",
+ "Xiaoyu (ZH)": "Xiaoyu",
+ "Yuewen (ZH)": "Yuewen",
+ "Lingyu (ZH)": "Lingyu",
+ # English
+ "Ava (EN)": "Ava",
+ "Bella (EN)": "Bella",
+ "Adam (EN)": "Adam",
+ "Nathan (EN)": "Nathan",
+ # Japanese
+ "Sakura (JA)": "Sakura",
+ "Yui (JA)": "Yui",
+ "Aoi (JA)": "Aoi",
+ "Hina (JA)": "Hina",
+ "Mei (JA)": "Mei",
+}
+PRESET_LABELS = list(VOICE_PRESETS.keys())
+DEFAULT_PRESET = "Junhao (ZH)"
+
+# ── AudioWorklet processor (loaded in browser via Blob URL) ──────────
+# Downmixes stereo-interleaved int16 PCM to mono float32 for playback.
+WORKLET_JS = r"""
+class TTSPlaybackProcessor extends AudioWorkletProcessor {
+ constructor() {
+ super();
+ this.queue = [];
+ this.buf = null;
+ this.pos = 0;
+ this.playing = false;
+ this.played = 0;
+ this.port.onmessage = (e) => {
+ if (e.data && e.data.type === 'clear') {
+ this.queue = []; this.buf = null; this.pos = 0; this.played = 0;
+ if (this.playing) { this.playing = false; this.port.postMessage({type:'stopped'}); }
+ return;
+ }
+ // Input: Int16Array of stereo-interleaved samples [L0,R0,L1,R1,...]
+ // Convert to mono float32 by averaging L+R channels.
+ const pcm = e.data;
+ const monoLen = Math.floor(pcm.length / 2);
+ const mono = new Float32Array(monoLen);
+ for (let i = 0; i < monoLen; i++) {
+ mono[i] = (pcm[i * 2] + pcm[i * 2 + 1]) / 65536.0;
+ }
+ this.queue.push(mono);
+ };
+ }
+ process(inputs, outputs) {
+ const out = outputs[0][0];
+ for (let i = 0; i < out.length; i++) {
+ if (!this.buf || this.pos >= this.buf.length) {
+ if (this.queue.length > 0) {
+ this.buf = this.queue.shift(); this.pos = 0;
+ } else {
+ for (let j = i; j < out.length; j++) out[j] = 0;
+ if (this.playing) { this.playing = false; this.port.postMessage({type:'stopped', played:this.played}); }
+ return true;
+ }
+ }
+ out[i] = this.buf[this.pos++];
+ this.played++;
+ }
+ if (!this.playing) { this.playing = true; this.port.postMessage({type:'started'}); }
+ return true;
+ }
+}
+registerProcessor('tts-playback-processor', TTSPlaybackProcessor);
+"""
+
+# ── Player HTML (container with metric cards) ────────────────────────
+PLAYER_HTML = """
+
+"""
+
+
+def _build_player_js(sample_rate: int) -> str:
+ """Build the JavaScript that powers the AudioWorklet player."""
+ return f"""
+
+"""
+
+
+def encode_audio_to_base64(audio_data: tuple) -> str:
+ """Encode Gradio audio input (sample_rate, numpy_array) to base64 data URL."""
+ sample_rate, audio_np = audio_data
+ if audio_np.dtype != np.int16:
+ if audio_np.dtype in (np.float32, np.float64):
+ audio_np = np.clip(audio_np, -1.0, 1.0)
+ audio_np = (audio_np * 32767).astype(np.int16)
+ else:
+ audio_np = audio_np.astype(np.int16)
+ buf = io.BytesIO()
+ sf.write(buf, audio_np, sample_rate, format="WAV")
+ wav_b64 = base64.b64encode(buf.getvalue()).decode("utf-8")
+ return f"data:audio/wav;base64,{wav_b64}"
+
+
+def build_payload(
+ text: str,
+ voice_preset: str,
+ ref_audio: tuple | None,
+ ref_text: str,
+ response_format: str = "pcm",
+ stream: bool = True,
+) -> dict:
+ """Build the /v1/audio/speech request payload."""
+ if not text or not text.strip():
+ raise gr.Error("Please enter text to synthesize.")
+
+ voice_name = VOICE_PRESETS.get(voice_preset, "Junhao")
+
+ payload: dict = {
+ "input": text.strip(),
+ "voice": voice_name,
+ "response_format": "pcm" if stream else response_format,
+ "stream": stream,
+ }
+
+ has_ref = ref_audio is not None
+ if has_ref:
+ payload["ref_audio"] = encode_audio_to_base64(ref_audio)
+ ref_text_stripped = ref_text.strip() if ref_text else ""
+ if ref_text_stripped:
+ payload["ref_text"] = ref_text_stripped
+ else:
+ raise gr.Error("Voice cloning requires a transcript of the reference audio.")
+
+ return payload
+
+
+def generate_speech(
+ api_base: str,
+ text: str,
+ voice_preset: str,
+ ref_audio: tuple | None,
+ ref_text: str,
+ response_format: str,
+) -> tuple:
+ """Non-streaming: call /v1/audio/speech and return full audio as (sr, np_array)."""
+ payload = build_payload(text, voice_preset, ref_audio, ref_text, response_format, stream=False)
+
+ try:
+ with httpx.Client(timeout=300.0) as client:
+ resp = client.post(
+ f"{api_base}/v1/audio/speech",
+ json=payload,
+ headers={"Content-Type": "application/json", "Authorization": "Bearer EMPTY"},
+ )
+ except httpx.TimeoutException:
+ raise gr.Error("Request timed out. The server may be busy.")
+ except httpx.ConnectError:
+ raise gr.Error(f"Cannot connect to server at {api_base}. Is the server running?")
+
+ if resp.status_code != 200:
+ raise gr.Error(f"Server error ({resp.status_code}): {resp.text}")
+
+ try:
+ if response_format == "pcm":
+ # PCM is stereo interleaved; downmix to mono for Gradio.
+ samples = np.frombuffer(resp.content, dtype=np.int16)
+ n = len(samples) - (len(samples) % 2)
+ left = samples[:n:2].astype(np.float32)
+ right = samples[1:n:2].astype(np.float32)
+ mono = (left + right) / 65536.0
+ return (PCM_SAMPLE_RATE, mono)
+ # WAV/MP3/FLAC: soundfile handles header parsing.
+ audio_np, sample_rate = sf.read(io.BytesIO(resp.content))
+ if audio_np.ndim > 1:
+ audio_np = audio_np.mean(axis=1)
+ return (int(sample_rate), audio_np.astype(np.float32))
+ except Exception as e:
+ raise gr.Error(f"Failed to decode audio: {e}")
+
+
+def create_app(api_base: str):
+ """Create the FastAPI app with streaming proxy + Gradio UI."""
+ fastapi_app = FastAPI()
+
+ # ── Streaming proxy (same-origin, no CORS issues) ────────────
+ @fastapi_app.post("/proxy/v1/audio/speech")
+ async def proxy_speech(request: Request):
+ body = await request.json()
+ logger.info(
+ "Proxy request: input=%r voice=%s stream=%s",
+ body.get("input", "")[:50],
+ body.get("voice"),
+ body.get("stream"),
+ )
+ try:
+ client = httpx.AsyncClient(timeout=300)
+ resp = await client.send(
+ client.build_request(
+ "POST",
+ f"{api_base}/v1/audio/speech",
+ json=body,
+ headers={"Authorization": "Bearer EMPTY", "Content-Type": "application/json"},
+ ),
+ stream=True,
+ )
+ except Exception as exc:
+ logger.exception("Proxy connection error")
+ await client.aclose()
+ return Response(content=str(exc), status_code=502)
+
+ if resp.status_code != 200:
+ content = await resp.aread()
+ logger.error("Proxy upstream error %d: %s", resp.status_code, content[:200])
+ await resp.aclose()
+ await client.aclose()
+ return Response(content=content, status_code=resp.status_code)
+
+ async def relay():
+ total = 0
+ try:
+ async for chunk in resp.aiter_bytes():
+ total += len(chunk)
+ yield chunk
+ except Exception:
+ logger.exception("Proxy relay error after %d bytes", total)
+ finally:
+ logger.info("Proxy relay done: %d bytes", total)
+ await resp.aclose()
+ await client.aclose()
+
+ return StreamingResponse(relay(), media_type="application/octet-stream")
+
+ # ── Gradio UI ────────────────────────────────────────────────
+ css = """
+ #generate-btn button { width: 100%; }
+ #streaming-player { border: 1px solid var(--border-color-primary) !important; border-radius: var(--block-radius) !important; padding: var(--block-padding) !important; }
+ """
+
+ theme = gr.themes.Default(
+ primary_hue=gr.themes.Color(
+ c50="#E8F5E9",
+ c100="#C8E6C9",
+ c200="#A5D6A7",
+ c300="#81C784",
+ c400="#66BB6A",
+ c500="#4CAF50",
+ c600="#43A047",
+ c700="#388E3C",
+ c800="#2E7D32",
+ c900="#1B5E20",
+ c950="#0D3B10",
+ ),
+ )
+
+ with gr.Blocks(title="MOSS-TTS-Nano Demo") as demo:
+ gr.HTML(f"""
+
+

+
+
MOSS-TTS-Nano Streaming Demo
+
+ 0.1B AR LM + MOSS-Audio-Tokenizer-Nano · 48 kHz · ZH / EN / JA
+ · Served by
+ vLLM-Omni
+ · {api_base}
+
+
+
+ """)
+
+ with gr.Row():
+ with gr.Column(scale=3):
+ text_input = gr.Textbox(
+ label="Text to Synthesize",
+ placeholder="Enter text in Chinese, English, or Japanese...",
+ lines=4,
+ )
+
+ voice_preset = gr.Dropdown(
+ choices=PRESET_LABELS,
+ value=DEFAULT_PRESET,
+ label="Voice Preset",
+ info="Built-in multilingual voices. ZH = Chinese, EN = English, JA = Japanese.",
+ )
+
+ with gr.Accordion("Custom Voice Clone (optional)", open=False):
+ gr.Markdown(
+ "Upload a reference audio clip (10-30 s) and provide its transcript "
+ "to clone that voice instead of using the built-in preset."
+ )
+ ref_audio = gr.Audio(
+ label="Reference Audio",
+ type="numpy",
+ sources=["upload", "microphone"],
+ )
+ ref_text = gr.Textbox(
+ label="Reference Audio Transcript (required for cloning)",
+ placeholder="Exact transcript of the reference audio...",
+ lines=2,
+ )
+
+ with gr.Row():
+ response_format = gr.Dropdown(
+ choices=["wav", "mp3", "flac", "pcm"],
+ value="pcm",
+ label="Audio Format",
+ interactive=False,
+ scale=1,
+ )
+ stream_checkbox = gr.Checkbox(
+ label="Stream (gapless)",
+ value=True,
+ info="AudioWorklet streaming (recommended)",
+ scale=1,
+ )
+
+ with gr.Row():
+ generate_btn = gr.Button(
+ "Generate Speech",
+ variant="primary",
+ size="lg",
+ elem_id="generate-btn",
+ scale=3,
+ )
+ reset_btn = gr.Button(
+ "Reset",
+ variant="secondary",
+ size="lg",
+ scale=1,
+ )
+
+ with gr.Column(scale=2):
+ player_html = gr.HTML(
+ value=PLAYER_HTML,
+ visible=True,
+ label="streaming player",
+ elem_id="streaming-player",
+ )
+ audio_output = gr.Audio(
+ label="Generated Audio",
+ interactive=False,
+ autoplay=True,
+ visible=False,
+ )
+ gr.Examples(
+ examples=[
+ ["Hello, this is MOSS-TTS-Nano speaking.", "Ava (EN)"],
+ ["The quick brown fox jumps over the lazy dog.", "Adam (EN)"],
+ ["MOSS-TTS-Nanoは、軽量なテキスト読み上げモデルです。", "Sakura (JA)"],
+ ],
+ inputs=[text_input, voice_preset],
+ label="Examples",
+ )
+ gr.HTML("""
+
+ """)
+
+ # Hidden textbox to pass payload from Python -> JavaScript
+ hidden_payload = gr.Textbox(visible=False, elem_id="tts-payload")
+
+ # ── Event wiring ─────────────────────────────────────────
+ def on_stream_change(stream: bool):
+ if stream:
+ return (
+ gr.update(value="pcm", interactive=False),
+ gr.update(visible=True), # player
+ gr.update(visible=False), # audio
+ )
+ return (
+ gr.update(value="wav", interactive=True),
+ gr.update(visible=False),
+ gr.update(visible=True),
+ )
+
+ stream_checkbox.change(
+ fn=on_stream_change,
+ inputs=[stream_checkbox],
+ outputs=[response_format, player_html, audio_output],
+ )
+
+ def on_reset():
+ return (
+ "", # text
+ None, # audio_output
+ "", # hidden_payload
+ PLAYER_HTML, # reset player
+ )
+
+ reset_btn.click(
+ fn=on_reset,
+ outputs=[text_input, audio_output, hidden_payload, player_html],
+ js="() => { if (window.ttsStop) window.ttsStop(); }",
+ )
+
+ all_inputs = [text_input, voice_preset, ref_audio, ref_text, response_format]
+
+ def on_generate(stream_enabled, *args):
+ import time as _time
+
+ text, voice, ref_a, ref_t, _fmt = args
+ if stream_enabled:
+ payload = build_payload(text, voice, ref_a, ref_t, stream=True)
+ payload["_nonce"] = int(_time.time() * 1000)
+ return json.dumps(payload), gr.update()
+ else:
+ audio = generate_speech(api_base, text, voice, ref_a, ref_t, _fmt)
+ return "", audio
+
+ generate_btn.click(
+ fn=on_generate,
+ inputs=[stream_checkbox] + all_inputs,
+ outputs=[hidden_payload, audio_output],
+ ).then(
+ fn=lambda p: p,
+ inputs=[hidden_payload],
+ outputs=[hidden_payload],
+ js="(p) => { if (p && p.trim()) { const d = JSON.parse(p); delete d._nonce; window.ttsGenerate(d); } return p; }",
+ )
+
+ demo.queue()
+
+ return gr.mount_gradio_app(
+ fastapi_app,
+ demo,
+ path="/",
+ css=css,
+ theme=theme,
+ head=_build_player_js(PCM_SAMPLE_RATE),
+ )
+
+
+def main():
+ parser = argparse.ArgumentParser(
+ description="Gradio demo for MOSS-TTS-Nano with gapless AudioWorklet streaming.",
+ )
+ parser.add_argument(
+ "--api-base", default=DEFAULT_API_BASE, help=f"API base URL (default: {DEFAULT_API_BASE})"
+ )
+ parser.add_argument("--host", default="0.0.0.0", help="Gradio host (default: 0.0.0.0)")
+ parser.add_argument("--port", type=int, default=7860, help="Gradio port (default: 7860)")
+ parser.add_argument("--share", action="store_true", help="Share publicly via Gradio tunnel")
+ args = parser.parse_args()
+
+ logging.basicConfig(level=logging.INFO)
+ print(f"Connecting to vLLM-Omni server at: {args.api_base}")
+
+ app = create_app(args.api_base)
+
+ import uvicorn
+ uvicorn.run(app, host=args.host, port=args.port)
+
+
+if __name__ == "__main__":
+ main()
diff --git a/examples/online_serving/moss_tts_nano/run_gradio_demo.sh b/examples/online_serving/moss_tts_nano/run_gradio_demo.sh
new file mode 100755
index 000000000..1fb5d1914
--- /dev/null
+++ b/examples/online_serving/moss_tts_nano/run_gradio_demo.sh
@@ -0,0 +1,47 @@
+#!/bin/bash
+# Launch MOSS-TTS-Nano server + Gradio demo together.
+#
+# Usage:
+# ./run_gradio_demo.sh
+# CUDA_VISIBLE_DEVICES=0 PORT=8091 GRADIO_PORT=7860 ./run_gradio_demo.sh
+
+set -e
+
+MODEL="${MODEL:-OpenMOSS-Team/MOSS-TTS-Nano}"
+PORT="${PORT:-8091}"
+GRADIO_PORT="${GRADIO_PORT:-7860}"
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+REPO_ROOT="$(cd "$SCRIPT_DIR/../../.." && pwd)"
+
+echo "Starting MOSS-TTS-Nano server (port $PORT)..."
+FLASHINFER_DISABLE_VERSION_CHECK=1 \
+vllm-omni serve "$MODEL" \
+ --stage-configs-path "$REPO_ROOT/vllm_omni/model_executor/stage_configs/moss_tts_nano.yaml" \
+ --host 0.0.0.0 \
+ --port "$PORT" \
+ --trust-remote-code \
+ --enforce-eager \
+ --omni &
+SERVER_PID=$!
+
+cleanup() {
+ echo "Stopping server (PID $SERVER_PID)..."
+ kill $SERVER_PID 2>/dev/null
+ wait $SERVER_PID 2>/dev/null
+}
+trap cleanup EXIT
+
+# Wait for server to be ready.
+echo "Waiting for server to start..."
+for i in $(seq 1 120); do
+ if curl -s "http://localhost:$PORT/health" > /dev/null 2>&1; then
+ echo "Server ready."
+ break
+ fi
+ sleep 2
+done
+
+echo "Starting Gradio demo (port $GRADIO_PORT)..."
+python "$SCRIPT_DIR/gradio_demo.py" \
+ --api-base "http://localhost:$PORT" \
+ --port "$GRADIO_PORT"
diff --git a/examples/online_serving/moss_tts_nano/run_server.sh b/examples/online_serving/moss_tts_nano/run_server.sh
new file mode 100755
index 000000000..c5254c428
--- /dev/null
+++ b/examples/online_serving/moss_tts_nano/run_server.sh
@@ -0,0 +1,24 @@
+#!/bin/bash
+# Launch vLLM-Omni server for MOSS-TTS-Nano
+#
+# Usage:
+# ./run_server.sh
+# CUDA_VISIBLE_DEVICES=0 PORT=8091 ./run_server.sh
+
+set -e
+
+MODEL="${MODEL:-OpenMOSS-Team/MOSS-TTS-Nano}"
+PORT="${PORT:-8091}"
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+REPO_ROOT="$(cd "$SCRIPT_DIR/../../.." && pwd)"
+
+echo "Starting MOSS-TTS-Nano server with model: $MODEL"
+
+FLASHINFER_DISABLE_VERSION_CHECK=1 \
+vllm-omni serve "$MODEL" \
+ --stage-configs-path "$REPO_ROOT/vllm_omni/model_executor/stage_configs/moss_tts_nano.yaml" \
+ --host 0.0.0.0 \
+ --port "$PORT" \
+ --trust-remote-code \
+ --enforce-eager \
+ --omni
diff --git a/vllm_omni/entrypoints/openai/serving_speech.py b/vllm_omni/entrypoints/openai/serving_speech.py
index 1d9754853..d4d57ae0f 100644
--- a/vllm_omni/entrypoints/openai/serving_speech.py
+++ b/vllm_omni/entrypoints/openai/serving_speech.py
@@ -50,6 +50,7 @@ _FISH_TTS_MODEL_STAGES = {"fish_speech_slow_ar"}
_COSYVOICE3_TTS_MODEL_STAGES = {"cosyvoice3_talker"}
_OMNIVOICE_TTS_MODEL_STAGES = {"omnivoice_generator"}
_VOXCPM2_TTS_MODEL_STAGES = {"latent_generator"}
+_MOSS_TTS_MODEL_STAGES = {"moss_tts_nano"}
_TTS_MODEL_STAGES: set[str] = (
_VOXTRAL_TTS_MODEL_STAGES
| _QWEN3_TTS_MODEL_STAGES
@@ -57,6 +58,7 @@ _TTS_MODEL_STAGES: set[str] = (
| _COSYVOICE3_TTS_MODEL_STAGES
| _OMNIVOICE_TTS_MODEL_STAGES
| _VOXCPM2_TTS_MODEL_STAGES
+ | _MOSS_TTS_MODEL_STAGES
)
_TTS_LANGUAGES: set[str] = {
"Auto",
@@ -294,6 +296,8 @@ class OmniOpenAIServingSpeech(OpenAIServing, AudioMixin):
return "omnivoice"
if model_stage in _VOXCPM2_TTS_MODEL_STAGES:
return "voxcpm2"
+ if model_stage in _MOSS_TTS_MODEL_STAGES:
+ return "moss_tts_nano"
return None
def _compute_max_instructions_length(self) -> int:
@@ -793,6 +797,8 @@ class OmniOpenAIServingSpeech(OpenAIServing, AudioMixin):
return self._validate_cosyvoice3_request(request)
if self._tts_model_type == "voxcpm2":
return None # VoxCPM2 accepts any text input
+ if self._tts_model_type == "moss_tts_nano":
+ return self._validate_moss_tts_request(request)
return self._validate_qwen_tts_request(request)
def _validate_ref_audio_format(self, ref_audio: str) -> str | None:
@@ -957,6 +963,30 @@ class OmniOpenAIServingSpeech(OpenAIServing, AudioMixin):
return None
+ def _validate_moss_tts_request(self, request: OpenAICreateSpeechRequest) -> str | None:
+ """Validate MOSS-TTS-Nano request. Only requires non-empty input text."""
+ if not request.input or not request.input.strip():
+ return "Input text cannot be empty"
+ return None
+
+ def _build_moss_tts_params(self, request: OpenAICreateSpeechRequest) -> dict[str, Any]:
+ """Build additional_information for MOSS-TTS-Nano.
+
+ Maps the standard /v1/audio/speech fields to MOSS-TTS-Nano's
+ additional_information keys (text, voice, mode, prompt_audio_path, etc.).
+ Values are wrapped in lists to match the vllm-omni convention.
+ """
+ params: dict[str, Any] = {
+ "text": [request.input],
+ }
+ if request.voice is not None:
+ params["voice"] = [request.voice]
+ if request.ref_text is not None:
+ params["prompt_text"] = [request.ref_text]
+ if request.max_new_tokens is not None:
+ params["max_new_frames"] = [request.max_new_tokens]
+ return params
+
def _validate_fish_tts_request(self, request: OpenAICreateSpeechRequest) -> str | None:
"""Validate Fish Speech request parameters. Returns error message or None.
@@ -1456,6 +1486,9 @@ class OmniOpenAIServingSpeech(OpenAIServing, AudioMixin):
elif self._tts_model_type == "cosyvoice3":
prompt = await self._build_cosyvoice3_prompt(request)
tts_params = {}
+ elif self._tts_model_type == "moss_tts_nano":
+ tts_params = self._build_moss_tts_params(request)
+ prompt = {"prompt_token_ids": [1], "additional_information": tts_params}
else:
tts_params = self._build_tts_params(request)
# Resolve ref_audio (explicit or auto-set for uploaded voices)
diff --git a/vllm_omni/model_executor/models/moss_tts_nano/modeling_moss_tts_nano.py b/vllm_omni/model_executor/models/moss_tts_nano/modeling_moss_tts_nano.py
index e2be3ea7e..61e320571 100644
--- a/vllm_omni/model_executor/models/moss_tts_nano/modeling_moss_tts_nano.py
+++ b/vllm_omni/model_executor/models/moss_tts_nano/modeling_moss_tts_nano.py
@@ -93,7 +93,7 @@ _DEFAULT_AUDIO_TOP_K = 25
_DEFAULT_AUDIO_REPETITION_PENALTY = 1.2
_DEFAULT_MAX_NEW_FRAMES = 375
_DEFAULT_VOICE = "Junhao"
-_DEFAULT_MODE = "voice_clone"
+_DEFAULT_MODE = "continuation"
def _pick(info: dict, key: str, default):
@@ -149,9 +149,6 @@ class MossTTSNanoForGeneration(nn.Module):
self._device: torch.device | None = None
self._lock = threading.Lock()
- # Dummy parameter so vLLM can resolve the device via next(parameters()).
- self._sentinel = nn.Parameter(torch.zeros(1), requires_grad=False)
-
# ------------------------------------------------------------------
# Weight loading
# ------------------------------------------------------------------
@@ -405,6 +402,13 @@ class MossTTSNanoForGeneration(nn.Module):
# vLLM boilerplate: embed_input_ids required by generation runner
# ------------------------------------------------------------------
+ def compute_logits(
+ self,
+ hidden_states: torch.Tensor,
+ ) -> torch.Tensor | None:
+ # Generation stage does not produce logits; satisfy VllmModelForTextGeneration protocol.
+ return None
+
def embed_input_ids(
self,
input_ids: torch.Tensor,
diff --git a/vllm_omni/model_executor/models/registry.py b/vllm_omni/model_executor/models/registry.py
index f8f11cb81..2411a388c 100644
--- a/vllm_omni/model_executor/models/registry.py
+++ b/vllm_omni/model_executor/models/registry.py
@@ -166,7 +166,7 @@ _OMNI_MODELS = {
## MOSS-TTS-Nano
"MossTTSNanoForCausalLM": (
"moss_tts_nano",
- "moss_tts_nano",
+ "modeling_moss_tts_nano",
"MossTTSNanoForGeneration",
),
"DyninOmniForConditionalGeneration": (
diff --git a/vllm_omni/model_executor/stage_configs/moss_tts_nano.yaml b/vllm_omni/model_executor/stage_configs/moss_tts_nano.yaml
index 1155247e9..7e27f05cf 100644
--- a/vllm_omni/model_executor/stage_configs/moss_tts_nano.yaml
+++ b/vllm_omni/model_executor/stage_configs/moss_tts_nano.yaml
@@ -26,7 +26,7 @@ async_chunk: false
stage_args:
- stage_id: 0
stage_type: llm
- is_comprehension: false
+ is_comprehension: true
runtime:
devices: "0"
engine_args: