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An OptiQ mixed-precision MLX quant of KAT-Coder-V2.5-Dev, a qwen3_5_moe coding model (256-routed-expert sparse MoE with hybrid linear + full attention).

Mixed 4/8-bit static build — per-layer bit-widths assigned to a 4.5 target bits-per-weight: 400 projections at 4-bit, 111 at 8-bit.
~4.51 bits per weight, 20 GB on disk.

Requirements

pip install -U optiq

qwen3_5_moe loads under stock mlx-lm too, but optiq serve adds mixed- precision loading, KV-cache quantization, and the OptiQ Lab.

Running it

optiq serve --model mlx-community/KAT-Coder-V2.5-Dev-OptiQ-4bit

Then use the OpenAI-compatible endpoint at http://localhost:8000/v1, the OptiQ Lab, or point optiq code at it. This is a reasoning coder — it thinks before it answers.