A hybrid, sparse model: 34 layers, 128 experts
Three kinds of layer, one repeating unit
- 14 memory · Gated DeltaNet: a linear-attention state per head, updated token by token
- 13 window · attention over the last 512 tokens, RoPE positions
- 7 global · full attention, no positional encoding; the last layer is always global
Mixture of experts in every layer
- 4 of 128 routed experts chosen per token by a router
- 1 shared expert always on
- 0.6B of 7.2B parameters active per token; hidden size 1,024, tied input and output embeddings
Optimizer
Muon + AdamW
Each momentum update is orthogonalised (Newton–Schulz) before it is applied, so every direction of a weight matrix moves at a similar rate instead of a few dominating.
4,096-token context window in training; 151,643-token vocabulary.