# Ornith 1.5 (35B-A3B)

> Uses the same sparse-hybrid decoder geometry as Qwen3.6 35B-A3B, paired with Ornith's self-improvement training recipe.

| Property | Value |
| --- | --- |
| Lab | Ornith (United States) |
| Released | 2026-08-23 |
| Decoder type | Sparse hybrid |
| Family | Hybrid MoE |
| Scale | 35B total, 3B active (8.6% active) |
| Context window | 262,144 tokens |
| Attention | 3:1 Gated DeltaNet and Gated Attention |
| Layer mix | 10 gated attention + 30 DeltaNet |
| KV cache / token (bf16) | 20 KiB (Very low) |
| License | MIT License |

**Key detail:** Matches Qwen3.6 35B-A3B's 40-layer decoder geometry, with 256 routed experts, top-8 routing, and one shared expert.

## Architecture concepts

- [Hybrid Attention (Hybrid attention)](https://llm-atlas-7or.pages.dev/concepts/hybrid-attention.md): Mixes cheap linear-attention or state-space layers with a few full-attention layers.
- [Grouped-Query Attention (GQA)](https://llm-atlas-7or.pages.dev/concepts/gqa.md): Several query heads share one key/value head, shrinking the KV cache with little quality loss.
- [Gated Attention (Gated attention)](https://llm-atlas-7or.pages.dev/concepts/gated-attention.md): A learned sigmoid gate scales the attention output before it re-enters the residual stream.
- [QK-Norm (QK-Norm)](https://llm-atlas-7or.pages.dev/concepts/qk-norm.md): RMSNorm applied to queries and keys before attention to keep logits well-behaved.
- [Short Convolution (ShortConv)](https://llm-atlas-7or.pages.dev/concepts/shortconv.md): A tiny causal depthwise convolution (kernel ≈ 4) that mixes each channel over the last few tokens.
- [Mixture of Experts (MoE)](https://llm-atlas-7or.pages.dev/concepts/moe.md): Many feed-forward experts, but a router sends each token to only a few of them.
- [Multi-Token Prediction (MTP)](https://llm-atlas-7or.pages.dev/concepts/mtp.md): Extra heads learn to predict several future tokens, and can draft tokens at inference.

## Links

- Architecture diagram: https://sebastianraschka.com/llm-architecture-gallery/images/architectures/ornith-1-5-35b-a3b.webp
- config.json: https://huggingface.co/ornith-ai/Ornith-1.5-35B-A3B/blob/main/config.json
- Tech report: https://ornith.ai/ornith_1_5.html
- Source card (source of truth): https://sebastianraschka.com/llm-architecture-gallery/#card-ornith-1-5-35b-a3b
- Web page: https://llm-atlas-7or.pages.dev/models/ornith-1-5-35b-a3b/
- JSON: https://llm-atlas-7or.pages.dev/api/models/ornith-1-5-35b-a3b.json

_Data from Sebastian Raschka's LLM Architecture Gallery (https://sebastianraschka.com/llm-architecture-gallery/). Synced 2026-11-04._