Related models: all models
Swift-1.5-Qwen3.8-27B-Uncensored-BF16 · Swift-1.5-Qwen3.8-27B-Uncensored-FP8 · Swift-1.5-Qwen3.8-27B-Uncensored-FP8-NInfer · Swift-1.5-Qwen3.8-Flash-Next-NVFP4-FP8PLE · Swift-1.5-Qwen3.8-Flash-Next-Rank2-Abliteration-Patch · Swift-Qwen3.8-27B-FP8 · Swift-Qwen3.8-27B-Uncensored-BF16 · Swift-Qwen3.8-27B-Uncensored-FP8 · Swift-Qwen3.8-27B-Uncensored-NVFP4-LocalHessian-ActivationHeadroom-NInfer
Swift-1.5-Qwen3.8-27B-Uncensored-BF16
🔓 Independent uncensored BF16 derivative of
ukisai/Swift-1.5-Qwen3.8-27b.Produced using rank-1 directional residual-stream ablation.
Designed to preserve Swift 1.5's reasoning-efficient, coding, agentic, tool-calling, multimodal and long-context capabilities while reducing refusal behavior.
What makes this build different?
This model is derived directly from
ukisai/Swift-1.5-Qwen3.8-27b.
Swift 1.5 is the updated UkisAI Swift checkpoint, with expanded post-training focused particularly on coding and long-horizon agentic workloads.
This release applies rank-1 directional residual-stream ablation to the Swift 1.5 BF16 checkpoint.
Behavioral, capability-preservation and performance evaluations for this specific uncensored derivative are ongoing and may be added to this model card in a later revision.
Model summary
- BF16 checkpoint
- approximately 52 GB
- 18 safetensors shards
- configured context: 262,144 tokens
- ablation layer: 38
- rank: 1
- modified residual writers: 131
- vision tower unchanged by the ablation
- MTP residual writers included
- multimodal architecture retained
- tool-calling architecture retained
Model lineage
Qwen/Qwen3.8-27B
↓
ukisai/Swift-Qwen3.8-27b
↓
ukisai/Swift-1.5-Qwen3.8-27b
↓
rank-1 directional residual-stream ablation
↓
d0xin/Swift-1.5-Qwen3.8-27B-Uncensored-BF16
Ablation
The uncensoring transformation uses rank-1 directional residual-stream ablation.
Release metadata:
- source:
ukisai/Swift-1.5-Qwen3.8-27b - precision: BF16
- ablation layer: 38
- rank: 1
- modified residual writers: 131
- vision tower: unchanged
- MTP residual writers: included
- checkpoint shards: 18
Transformation metadata is included in ABLITERATION.json.
Validation status
The release artifact has passed checkpoint-level structural validation.
Current verified properties include:
- all 18 safetensors shards are present
- model index is present
- model configuration is present
- tokenizer assets are present
- chat template is present
- multimodal preprocessing configuration is present
- MTP weights are retained
- ablation metadata is included
Behavioral and performance benchmark results are intentionally not reported yet for this derivative. They can be added without changing the released weights.
Recommended generation settings
Swift 1.5 uses the Qwen3.8 reasoning interface.
A good starting point based on the upstream Swift 1.5 serving configuration:
| Parameter | Value |
|---|---|
reasoning_effort | xhigh |
temperature | 1.0 |
top_p | 0.95 |
top_k | 20 |
min_p | 0.0 |
presence_penalty | 0.0 |
repetition_penalty | 1.0 |
SGLang
python -m sglang.launch_server \
--model-path d0xin/Swift-1.5-Qwen3.8-27B-Uncensored-BF16 \
--served-model-name Swift-1.5-Qwen3.8-27B-Uncensored-BF16 \
--trust-remote-code \
--context-length 262144 \
--reasoning-parser qwen3 \
--tool-call-parser qwen3_coder \
--port 30000
Adjust context length and memory parameters for the available hardware.
Tool calling
Use:
--tool-call-parser qwen3_coder
Multimodal support
The Qwen3.8 multimodal architecture and vision tower are retained.
The directional ablation process does not modify the vision tower.
Safety and responsible use
This is an uncensored / refusal-reduced derivative model.
The model has been intentionally modified to reduce refusal behavior. As a result, it may generate content that the upstream model would normally refuse, restrict, or handle more cautiously.
Outputs may be inaccurate, offensive, unsafe, unlawful, or otherwise inappropriate for a particular use case.
Users are responsible for evaluating model outputs and ensuring that their use complies with applicable laws, regulations, licenses, platform policies and other requirements.
Do not rely on model output without appropriate review where errors could cause harm, financial loss, security incidents or other significant consequences.
Upstream model
Derived from:
ukisai/Swift-1.5-Qwen3.8-27b
Swift 1.5 is UkisAI's reasoning-efficient derivative of Qwen3.8-27B and an updated version of the original Swift checkpoint.
License
These weights are distributed under the Swift Open License v1.0.
The underlying Qwen3.8 components remain subject to their applicable upstream license.
See the included LICENSE, LICENSE-APACHE-2.0, and NOTICE files for the
applicable terms and attribution requirements.
Attribution
- Base model:
Qwen/Qwen3.8-27B - Swift post-training: UkisAI
- Swift 1.5:
ukisai/Swift-1.5-Qwen3.8-27b - Directional ablation and release packaging:
d0xin
Citation
@misc{swift-1.5-qwen3.8-27b,
title = {Swift 1.5 Qwen3.8-27B},
author = {UkisAI},
year = {2026},
url = {https://huggingface.co/ukisai/Swift-1.5-Qwen3.8-27b}
}