Devstral 2: Run Mistral's Open Coding Agent Locally

Proprietary coding agents are powerful, but every token you send to a cloud API is a token that leaves your codebase. Devstral 2, released December 9, 2025 by Mistral AI, changes that calculus. At 72.2% on SWE-bench Verified — the industry-standard benchmark for real GitHub issue resolution — it matches Claude Sonnet 4.5's general performance territory while running fully on-premise on a single RTX 4090 or a Mac with 32GB RAM. This guide covers what Devstral 2 and Devstral Small 2 are, their spe