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Figure 1: Laguna XS 2.1 · diagram by Sebastian Raschka · click to zoom
Sparse MoEPoolside 🇺🇸 · July 2, 2026

Laguna XS 2.1 (33B)

Poolside's 33B Laguna refresh extends the sparse MoE architecture to 262k context while keeping about 3B parameters active per token.

Key detail

Uses 256 routed experts with top-8 routing plus one shared expert, a dense first layer, and per-layer query-head counts.

Total params

33B

Active / token

3B

Context

256K

Fact sheet

Scale
33B total, 3B active (9.1% active)
Context window
262,144 tokens
Decoder type
Sparse MoE
Attention
Gated GQA with QK-Norm and 3:1 sliding-window/global attention
Layer mix
30 sliding-window + 10 global GQA
KV cache / token (bf16)
160 KiB · Moderate
License
OpenMDW License 1.1
Released

Efficiency

Parameters active per token

9.1%

3B of 33B weights run for each token.

KV cache per token (bf16)

160 KiB

Smaller than 31% of models in the atlas. How it’s calculated

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