Rebuilding Devin for Claude Sonnet 4.5: Lessons and Challenges

Cognition · cognition.com· published 2025-09-29 00:00 · seen 2026-09-02 · ai

We rebuilt Devin for Claude Sonnet 4.5. The new version is 2x faster, 12% better on our Junior Developer Evals, and it's available now in Agent Preview. For users who prefer the old Devin, that remains available.