{"type": "article", "title": "Leanstral 1.5: ICYMI: Mistral released Leanstral 1.5, a SOTA open model for Lean 4 proof engineering. > Developers use Lean 4 as a general-purpose functional language (for CLI tools and libraries)…", "publisher": "Web Pulse", "url": "https://wpnews.pro/news/leanstral-1-5-icymi-mistral-released-leanstral-1-5-a-sota-open-model-for-lean-4", "original_source": "https://outyet.ai/models/leanstral-1-5", "published": "2026-07-04T00:00:00+00:00", "accessed": "2026-07-04", "id": "leanstral-1-5-icymi-mistral-released-leanstral-1-5-a-sota-open-model-for-lean-4"}