vmlx

Local AI Engine for Apple Silicon

Run LLMs, VLMs, and image generation models entirely on your Mac.
OpenAI + Anthropic + Ollama compatible API. No cloud. No API keys. No data leaving your machine.

Quickstart • Models • Features • Image Gen • API • Desktop App • JANG • CLI • Config • Contributing • 한국어

JANG 2-bit destroys MLX 4-bit on MiniMax M2.5:

Quantization	MMLU (200q)	Size
JANG_2L (2-bit)	74%	89 GB
MLX 4-bit	26.5%	120 GB
MLX 3-bit	24.5%	93 GB
MLX 2-bit	25%	68 GB

Adaptive mixed-precision keeps critical layers at higher precision. Scores at jangq.ai. Models at JANGQ-AI.

Chat with any MLX model -- thinking mode, streaming, and syntax highlighting	Agentic chat with full coding capabilities -- tool use and structured output

Quickstart

Install from PyPI

Published on PyPI as vmlx -- install and run in one command:

# Recommended: uv (fast, no venv hassle)
brew install uv
uv tool install vmlx
vmlx serve mlx-community/Qwen3-8B-4bit

# Or: pipx (isolates from system Python)
brew install pipx
pipx install vmlx
vmlx serve mlx-community/Qwen3-8B-4bit

# Or: pip in a virtual environment
python3 -m venv ~/.vmlx-env && source ~/.vmlx-env/bin/activate
pip install vmlx
vmlx serve mlx-community/Qwen3-8B-4bit

Note: On macOS 14+, bare pip install fails with "externally-managed-environment". Use uv, pipx, or a venv.

Your local AI server is now running at http://0.0.0.0:8000 with an OpenAI + Anthropic compatible API. Works with any model from mlx-community -- thousands of models ready to go.

Or download the desktop app

Get MLX Studio -- a native macOS app with chat UI, model management, image generation, and developer tools. No terminal required. Just download the DMG and drag to Applications.

Use with OpenAI SDK

from openai import OpenAI

client = OpenAI(base_url="http://localhost:8000/v1", api_key="not-needed")
response = client.chat.completions.create(
    model="local",
    messages=[{"role": "user", "content": "Hello!"}],
    stream=True,
)
for chunk in response:
    print(chunk.choices[0].delta.content or "", end="", flush=True)

Use with Anthropic SDK

import anthropic

client = anthropic.Anthropic(base_url="http://localhost:8000/v1", api_key="not-needed")
message = client.messages.create(
    model="local",
    max_tokens=1024,
    messages=[{"role": "user", "content": "Hello!"}],
)
print(message.content[0].text)

Use with curl

curl http://localhost:8000/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "local",
    "messages": [{"role": "user", "content": "Hello!"}],
    "stream": true
  }'

Model Support

vMLX runs any MLX model. Point it at a HuggingFace repo or local path and go.

Features

Inference Engine

5-Layer Cache Architecture

Request -> Tokens
    |
L1: Memory-Aware Prefix Cache (or Paged Cache)
    | miss
L2: Disk Cache (or Block Disk Store)
    | miss
Inference -> float16 KV states
    |
KV Quantization -> q4/q8 for storage
    |
Store back into L1 + L2

Tool Calling

Auto-detected parsers for every major model family:

qwen - llama - mistral - hermes - deepseek - glm47 - minimax - nemotron - granite - functionary - xlam - kimi - step3p5

Reasoning / Thinking Mode

Auto-detected reasoning parsers that extract <think> blocks:

qwen3 (Qwen3, QwQ, MiniMax, StepFun) - deepseek_r1 (DeepSeek R1, Gemma 3, GLM, Phi-4) - openai_gptoss (GLM Flash, GPT-OSS)

Audio

Image Generation & Editing

Generate and edit images locally with Flux models via mflux.

pip install vmlx[image]

# Image generation
vmlx serve schnell                    # or dev, z-image-turbo
vmlx serve ~/.mlxstudio/models/image/flux1-schnell-4bit

# Image editing
vmlx serve qwen-image-edit            # instruction-based editing

Generation API

curl http://localhost:8000/v1/images/generations \
  -H "Content-Type: application/json" \
  -d '{
    "model": "schnell",
    "prompt": "A cat astronaut floating in space with Earth in the background",
    "size": "1024x1024",
    "n": 1
  }'

# Python (OpenAI SDK)
response = client.images.generate(
    model="schnell",
    prompt="A cat astronaut floating in space",
    size="1024x1024",
    n=1,
)

Editing API

# Edit an image with a text prompt (Flux Kontext / Qwen Image Edit)
curl http://localhost:8000/v1/images/edits \
  -H "Content-Type: application/json" \
  -d '{
    "model": "flux-kontext",
    "prompt": "Change the background to a sunset",
    "image": "<base64-encoded-image>",
    "size": "1024x1024",
    "strength": 0.8
  }'

# Python
import base64
with open("source.png", "rb") as f:
    image_b64 = base64.b64encode(f.read()).decode()

response = requests.post("http://localhost:8000/v1/images/edits", json={
    "model": "flux-kontext",
    "prompt": "Make the sky purple",
    "image": image_b64,
    "size": "1024x1024",
    "strength": 0.8,
})

Supported Image Models

Generation Models:

Editing Models:

API Reference

API Gateway

The desktop app runs an API Gateway on a single port (default 8080) that routes requests to all loaded models by name. Run multiple models simultaneously and access them all through one URL.

# All models accessible through the gateway
curl http://localhost:8080/v1/chat/completions \
  -d '{"model": "Qwen3.5-122B", "messages": [{"role": "user", "content": "Hi"}]}'

# Works with Ollama CLI too
OLLAMA_HOST=http://localhost:8080 ollama run Qwen3.5-122B

The gateway supports OpenAI, Anthropic, and Ollama wire formats. Configure the port in the API tab.

Endpoints

OpenAI / Anthropic

Ollama

curl Examples

Chat completion (streaming)

curl http://localhost:8000/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "local",
    "messages": [{"role": "user", "content": "Explain quantum computing in 3 sentences."}],
    "stream": true,
    "temperature": 0.7
  }'

Chat completion with thinking mode

curl http://localhost:8000/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "local",
    "messages": [{"role": "user", "content": "Solve: what is 23 * 47?"}],
    "enable_thinking": true,
    "stream": true
  }'

Tool calling

curl http://localhost:8000/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "local",
    "messages": [{"role": "user", "content": "What is the weather in Tokyo?"}],
    "tools": [{
      "type": "function",
      "function": {
        "name": "get_weather",
        "description": "Get current weather for a location",
        "parameters": {
          "type": "object",
          "properties": {
            "location": {"type": "string", "description": "City name"}
          },
          "required": ["location"]
        }
      }
    }]
  }'

Anthropic Messages API

curl http://localhost:8000/v1/messages \
  -H "Content-Type: application/json" \
  -H "x-api-key: not-needed" \
  -H "anthropic-version: 2023-06-01" \
  -d '{
    "model": "local",
    "max_tokens": 1024,
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

Embeddings

curl http://localhost:8000/v1/embeddings \
  -H "Content-Type: application/json" \
  -d '{
    "model": "local",
    "input": "The quick brown fox jumps over the lazy dog"
  }'

Text-to-speech

curl http://localhost:8000/v1/audio/speech \
  -H "Content-Type: application/json" \
  -d '{
    "model": "kokoro",
    "input": "Hello, welcome to vMLX!",
    "voice": "af_heart"
  }' --output speech.wav

Speech-to-text

curl http://localhost:8000/v1/audio/transcriptions \
  -F [email protected] \
  -F model=whisper

Image generation

curl http://localhost:8000/v1/images/generations \
  -H "Content-Type: application/json" \
  -d '{
    "model": "schnell",
    "prompt": "A mountain landscape at sunset",
    "size": "1024x1024"
  }'

Reranking

curl http://localhost:8000/v1/rerank \
  -H "Content-Type: application/json" \
  -d '{
    "model": "local",
    "query": "What is machine learning?",
    "documents": [
      "ML is a subset of AI",
      "The weather is sunny today",
      "Neural networks learn from data"
    ]
  }'

Cache stats

curl http://localhost:8000/v1/cache/stats

Health check

curl http://localhost:8000/health

Desktop App

vMLX includes a native macOS desktop app (MLX Studio) with 5 modes:

Image generation and editing with Flux models	Developer tools -- model conversion and diagnostics
Anthropic Messages API endpoint -- full compatibility	GGUF to MLX conversion -- bring your own models

Download

Get the latest DMG from MLX Studio Releases, or build from source:

git clone https://github.com/jjang-ai/vmlx.git
cd vmlx/panel
npm install && npm run build
npx electron-builder --mac dmg

Menu Bar

vMLX lives in your menu bar showing all running models, GPU memory usage, and quick controls.

Advanced Quantization

vMLX supports standard MLX quantization (4-bit, 8-bit uniform) out of the box. For users who want to push further, JANG adaptive mixed-precision assigns different bit widths to different layer types -- attention gets more bits, MLP layers get fewer -- achieving better quality at the same model size.

JANG Profiles

Convert

pip install vmlx[jang]

# Standard MLX quantization
vmlx convert my-model --bits 4

# JANG adaptive quantization
vmlx convert my-model --jang-profile JANG_3M

# Activation-aware calibration (better at 2-3 bit)
vmlx convert my-model --jang-profile JANG_2L --calibration-method activations

# Serve the converted model
vmlx serve ./my-model-JANG_3M --continuous-batching --use-paged-cache

Pre-quantized JANG models are available at JANGQ-AI on HuggingFace.

CLI Commands

vmlx serve <model>              # Start inference server
vmlx convert <model> --bits 4   # MLX uniform quantization
vmlx convert <model> -j JANG_3M # JANG adaptive quantization
vmlx info <model>               # Model metadata and config
vmlx doctor <model>             # Run diagnostics
vmlx bench <model>              # Performance benchmarks

Configuration

Server Options

vmlx serve <model> \
  --host 0.0.0.0 \              # Bind address (default: 0.0.0.0)
  --port 8000 \                 # Port (default: 8000)
  --api-key sk-your-key \       # Optional API key authentication
  --continuous-batching \       # Enable concurrent request handling
  --enable-prefix-cache \       # Reuse KV states for repeated prompts
  --use-paged-cache \           # Block-based KV cache with dedup
  --kv-cache-quantization q8 \  # Quantize cache: q4 or q8
  --enable-disk-cache \         # Persist cache to SSD
  --enable-jit \                # JIT Metal kernel compilation
  --tool-call-parser auto \     # Auto-detect tool call format
  --reasoning-parser auto \     # Auto-detect thinking format
  --log-level INFO \            # Logging: DEBUG, INFO, WARNING, ERROR
  --max-model-len 8192 \        # Max context length
  --speculative-model <model> \ # Draft model for speculative decoding
  --enable-pld \                # Prompt Lookup Decoding — no draft model, best for code/JSON/schemas
  --cors-origins "*"            # CORS allowed origins

Quantization Options

vmlx convert <model> \
  --bits 4 \                    # Uniform quantization bits: 2, 3, 4, 6, 8
  --group-size 64 \             # Quantization group size (default: 64)
  --output ./output-dir \       # Output directory
  --jang-profile JANG_3M \      # JANG mixed-precision profile
  --calibration-method activations  # Activation-aware calibration

Image Generation & Editing Options

pip install vmlx[image]

# Generation models
vmlx serve schnell \            # or dev, z-image-turbo
  --image-quantize 4 \          # Quantization: 4, 8 (omit for full precision)
  --port 8001

# Editing models
vmlx serve qwen-image-edit \    # Instruction-based editing (full precision only)
  --port 8001

# Local model directory
vmlx serve ~/.mlxstudio/models/image/FLUX.1-schnell-mflux-4bit

Audio Options

TTS and STT require the mlx-audio package:

pip install mlx-audio

# TTS: serve Kokoro model
vmlx serve kokoro --port 8002

# STT: serve Whisper model
vmlx serve whisper --port 8003

Optional Dependencies

pip install vmlx              # Core: text LLMs, VLMs, embeddings, reranking
pip install vmlx[image]       # + Image generation (mflux)
pip install vmlx[jang]        # + JANG quantization tools
pip install vmlx[dev]         # + Development/testing tools
pip install vmlx[image,jang]  # Multiple extras

Architecture

+--------------------------------------------+
|          Desktop App (Electron)             |
|   Chat | Server | Image | Tools | API      |
+--------------------------------------------+
|          Session Manager (TypeScript)       |
|   Process spawn | Health monitor | Tray     |
+--------------------------------------------+
|         vMLX Engine (Python / FastAPI)       |
|  +--------+  +---------+  +-----------+    |
|  |Simple  |  | Batched |  | ImageGen  |    |
|  |Engine  |  | Engine  |  | Engine    |    |
|  +---+----+  +----+----+  +-----+-----+    |
|      |            |              |          |
|  +---+------------+--+    +-----+-----+    |
|  | mlx-lm / mlx-vlm  |    |  mflux    |    |
|  +--------+-----------+    +-----------+    |
|           |                                 |
|  +--------+----------------------------+    |
|  |       MLX Metal GPU Backend          |    |
|  | quantized_matmul | KV cache | SDPA   |    |
|  +--------------------------------------+    |
+--------------------------------------------+
|  L1: Prefix Cache (Memory-Aware / Paged)    |
|  L2: Disk Cache (Persistent / Block Store)  |
|  KV Quant: q4/q8 at storage boundary       |
+--------------------------------------------+

Contributing

Contributions are welcome. Here is how to set up a development environment:

git clone https://github.com/jjang-ai/vmlx.git
cd vmlx

# Python engine
python -m venv .venv && source .venv/bin/activate
pip install -e ".[dev,jang,image]"
pytest tests/ -k "not Async"    # 2000+ tests

# Electron desktop app
cd panel && npm install
npm run dev                      # Development mode with hot reload
npx vitest run                   # 1545+ tests

Project Structure

vmlx/
  vmlx_engine/          # Python inference engine (FastAPI server)
  panel/                # Electron desktop app (React + TypeScript)
    src/main/           # Electron main process
    src/renderer/       # React frontend
    src/preload/        # IPC bridge
  tests/                # Python test suite
  assets/               # Screenshots and logos

Guidelines

• Run the full test suite before submitting PRs
• Follow existing code style and patterns
• Include tests for new features
• Update documentation for user-facing changes

License

Apache License 2.0 -- see LICENSE.

Built by Jinho Jang ([email protected])
JANGQ AI • PyPI • GitHub • Downloads

한국어 (Korean)

vMLX — Apple Silicon을 위한 로컬 AI 엔진

Mac에서 LLM, VLM, 이미지 생성 및 편집 모델을 완전히 로컬로 실행하세요.
OpenAI + Anthropic 호환 API. 클라우드 없음. API 키 불필요. 데이터가 기기를 떠나지 않습니다.

빠른 시작

pip install vmlx
vmlx serve mlx-community/Llama-3.2-3B-Instruct-4bit

주요 기능

이미지 생성

pip install vmlx[image]
vmlx serve schnell          # 빠른 생성 (4 단계)
vmlx serve dev              # 고품질 생성 (20 단계)

이미지 편집

vmlx serve qwen-image-edit  # 텍스트 지시 기반 이미지 편집

# 이미지 편집 API
curl http://localhost:8000/v1/images/edits \
  -H "Content-Type: application/json" \
  -d '{
    "model": "qwen-image-edit",
    "prompt": "배경을 해질녘으로 변경",
    "image": "<base64 인코딩된 이미지>",
    "size": "1024x1024",
    "strength": 0.8
  }'

데스크톱 앱 (MLX Studio)

macOS 네이티브 데스크톱 앱으로 5가지 모드를 제공합니다:

설치

pip install vmlx              # 기본: 텍스트 LLM, VLM, 임베딩
pip install vmlx[image]       # + 이미지 생성/편집 (mflux)
pip install vmlx[jang]        # + JANG 양자화 도구
pip install vmlx[audio]       # + TTS/STT (mlx-audio)

라이선스

Apache License 2.0 — LICENSE 참조.

개발자: 장진호 ([email protected])
JANGQ AI • Ko-fi로 후원하기