# vLLM Patch: qwen3_next.py — Variable expert count per layer

**File:** `vllm/model_executor/models/qwen3_next.py`
**Class:** `Qwen3NextSparseMoeBlock.__init__`
**Tested on:** vLLM 0.16.1rc1.dev188

## What it does

Reads `num_experts_per_layer` (a list) from the model config to support REAP-pruned models
where each layer has a different number of experts. Falls back to `config.num_experts` for
standard models.

## Patch

In `Qwen3NextSparseMoeBlock.__init__`, find where `self.n_routed_experts` is set
(after `self.ep_size = ...`), and replace the fixed assignment with:

```python
        # Support variable expert counts per layer (REAP pruned models)
        layer_idx = extract_layer_index(prefix)
        if hasattr(config, 'num_experts_per_layer') and config.num_experts_per_layer:
            num_experts = config.num_experts_per_layer[layer_idx]
        else:
            num_experts = config.num_experts
        self.n_routed_experts = num_experts
```

The `extract_layer_index` function is already imported from `.utils` in the stock file.