MLX for text: Apple's secret weapon for local AI¶
Apple's MLX framework was initially focused on image models. With the latest release, text generation is now a first-class citizen — and the results on Apple Silicon are stunning.
Why MLX matters¶
Unlike llama.cpp (which uses Metal shaders) or Ollama (which wraps llama.cpp), MLX is a native Apple Silicon framework from Apple's ML research team. It uses:
- Unified memory: No CPU/GPU copies — weights live in one place
- Lazy computation: Builds a compute graph, then optimizes and executes
- Multi-device: Single API for CPU, GPU, and ANE (Neural Engine)
The result? Performance that sometimes exceeds llama.cpp by 20-30% on the same hardware.
Benchmarks¶
Tested on MacBook Pro M3 Pro (18GB) with Mistral 7B Q4:
| Framework | Prompt tok/s | Gen tok/s | Memory |
|---|---|---|---|
| MLX (text) | 145 | 55 | 6.2 GB |
| llama.cpp | 112 | 42 | 6.8 GB |
| Ollama | 110 | 41 | 6.8 GB |
Getting started¶
from mlx_lm import load, generate
model, tokenizer = load("mlx-community/Mistral-7B-Instruct-v0.3-4bit")
response = generate(
model, tokenizer,
prompt="Explain quantum computing in simple terms",
max_tokens=256,
temp=0.7,
)
print(response)
The catch¶
MLX only runs on Apple Silicon (M1/M2/M3/M4). There's no x86 or CUDA support. It's also younger than llama.cpp, so the model ecosystem is smaller. But for Mac developers, it's already the fastest option.
Bottom line¶
If you develop on a Mac, MLX deserves a serious look. The performance advantage is real, and Apple's backing means it will only improve.