Lilian Weng, the Thinking Machines cofounder who announced her departure earlier this week, citing startup-related stress and illness, is rejoining OpenAI. She'll be working on using AI to develop new models (recursive self-improvement). w/ @amir …↗

✅ Lilian Weng (@lilianweng) has joined OpenAI.↗

new post on harness engineering for AI self-improvement: lilianweng.github.io/posts/2026-07-… It is hard to forecast how much the future of RSI will rely on harnesses. Likely harness engineering will evolve in the direction of self-improvement and enable auto-research, and, in t…↗