Laguna XS 2.1 is Poolside's small agentic coding model, released July 2026 under the permissive OpenMDW-1.1 license and explicitly designed for long-horizon coding work on a local machine. A 33B-total / 3B-active Mixture-of-Experts, it scores 70.9 on SWE-bench Verified — remarkable for its size — with native tool use and interleaved thinking between tool calls.
The architecture is tuned for local efficiency: 30 of its 40 layers use sliding-window attention and the KV cache is FP8-quantized, keeping memory low across the 256K context window. The 20 GB Q4_K_M (the default Ollama tag) fits a 24 GB GPU or a 36 GB Mac, and with only 3B active parameters per token it generates fast even with partial CPU offload.