# Recursive Flint (40B-A2.5B)

> Recursive's coding model uses two dense FFN layers followed by 47 MoE layers. The active-parameter count includes the output head.

| Property | Value |
| --- | --- |
| Lab | Recursive (United States) |
| Released | 2026-10-18 |
| Decoder type | Sparse MoE |
| Family | Sparse MoE |
| Scale | 39.8B total, 2.5B active (6.3% active) |
| Context window | 262,144 configured; 512k supported tokens |
| Attention | GQA with QK-Norm, learned attention sinks, and sliding-window/global attention |
| Layer mix | 35 sliding-window + 14 global GQA |
| KV cache / token (bf16) | 98 KiB (Moderate) |
| License | Apache License 2.0 |

**Key detail:** Uses top-6 routing over 256 experts plus one shared expert, with RoPE in local layers, NoPE in global layers, and a local window covering the current token and 512 preceding tokens.

## Architecture concepts

- [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.
- [Sliding Window Attention (SWA)](https://llm-atlas-7or.pages.dev/concepts/swa.md): Some layers only attend to a local window of recent tokens instead of the whole context.
- [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.
- [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.
- [No Positional Embeddings (NoPE)](https://llm-atlas-7or.pages.dev/concepts/nope.md): Some or all layers drop explicit positional encodings and rely on the causal mask.

## Links

- Architecture diagram: https://sebastianraschka.com/llm-architecture-gallery/images/architectures/recursive-flint.webp
- config.json: https://huggingface.co/RecursiveSI/flint/blob/main/config.json
- Tech report: https://recursive.com/updates/introducing-recursive-flint
- Source card (source of truth): https://sebastianraschka.com/llm-architecture-gallery/#card-recursive-flint-40b-a2-5b
- Web page: https://llm-atlas-7or.pages.dev/models/recursive-flint-40b-a2-5b/
- JSON: https://llm-atlas-7or.pages.dev/api/models/recursive-flint-40b-a2-5b.json

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