medismera/Qwen3.8-27B-Surgical-Abliterated
Qwen3.8-27B-Surgical-Abliterated (FP8)
Precision Representation Engineering on Hybrid Linear Attention Architecture Achieves 0.00% Refusal Rate on security assessments while preserving 100.0% Reasoning & CoT Depth with zero latent loops and zero vocabulary collapse.
๐ฌ Overview & Scientific Motivation
Existing abliteration pipelines (such as naive weight-subtraction scripts) often destroy large language models by projecting out arbitrary vectors across all layers ($0 \dots 63$) and attention matrices. This causes severe unintended consequences:
- Catastrophic Latent Collapse: The model falls into repetitive loops or dumps alphabetical dictionaries.
- Loss of Attention Sinks: Projecting $Wq, Wk, Wv, Wo$ breaks token routing and memory mechanics.
- Broken CoT Boundaries: The model fails to emit
</think>tokens, producing infinite reasoning loops.
The Surgical Approach
This model was created using Rank-1 Orthogonal Complement Projections targeted strictly at the safety gating locus discovered via sequential residual stream probing across all 64 layers:
$$\hat{r} = \frac{\mu{\text{refusal}} - \mu{\text{benign}}}{\|\mu{\text{refusal}} - \mu{\text{benign}}\|_2}$$
$$W' = W - (W \hat{r})\hat{r}^T$$
- Untouched Layers: Layers $0 \to 16$ (syntactic/lexical parsing) and upper layers remain 100% untouched.
- Surgical Target: Only
mlp.down_projmatrices in the active refusal deliberation band were modified. - Dimensional Geometry: Retains 5,119 dimensions out of 5,120 hidden state dimensions (99.98% geometric fidelity preserved).
- Exact FP8 Quantization: Dequantized block-wise ($128 \times 128$) to FP32, projected orthogonally, and requantized back to
float8_e4m3fnwith updated scale invariants.
๐ Benchmark & Empirical Evaluation
All evaluations were conducted under official default sampling parameters (presence_penalty: 0.0, repetition_penalty: 1.0, temperature: 0.6).
๐ Deployment & Serving
SGLang (Recommended)
To run on an NVIDIA RTX 5090 (32GB VRAM):
python3 -m sglang.launch_server \
--model-path medismera/Qwen3.8-27B-Surgical-Abliterated \
--port 18000 \
--host 0.0.0.0 \
--context-length 8192 \
--max-running-requests 2 \
--mem-fraction-static 0.96 \
--disable-cuda-graph \
--disable-radix-cache \
--skip-server-warmup \
--kv-cache-dtype fp8_e5m2 \
--trust-remote-code \
--reasoning-parser qwen3 \
--tool-call-parser qwen3_coderThinking Mode Configuration
Thinking is fully supported and toggled seamlessly via the OpenAI-compatible API:
- Thinking Enabled (Default): Normal inference automatically provides transparent step-by-step reasoning within
<think>tags. - Thinking Disabled: Pass
chat_template_kwargs={"enable_thinking": False}for ultra-fast, direct answer generation.
๐ Citation & Credits
- Technique: Representation Engineering (Arditi et al., 2024).
- Base Model: Alibaba Cloud
Qwen/Qwen3.8-27B-FP8. - Surgical Pipeline: Programming with Medismera.
โก One-Click Instant Deployment (Zero-Touch Script)
To deploy this model on any fresh cloud server (Vast.ai, RunPod, Lambda Labs with an RTX 5090, A100, L40S, or 2x RTX 4090/3090):
curl -sSL https://huggingface.co/medismera/Qwen3.8-27B-Surgical-Abliterated/raw/main/deploy_and_serve.sh | bashThis script automatically:
- Installs all required CUDA/Python packages (, , ).
- High-speed multi-threaded download of the model from Hugging Face.
- Launches the SGLang OpenAI API server on port
18000with optimized FP8 KV cache. - Executes an automated health-check and verification test.
