TypeSafe AI Seeks $1 Billion at $10 Billion Valuation Days After Jev Launch Breaks Adoption Records

TypeSafe AI, a stealth AI startup that emerged three days ago, is in talks to raise over $1 billion at a valuation above $10 billion—a dramatic 50x jump from its $200 million seed valuation, fueled by explosive early adoption of its Jev decision model. The company, founded by former OpenAI researcher Diogo Almeida and co-inventors of reinforcement learning for human feedback (RLHF) and ChatGPT, announced a $40 million seed round led by DCVC on September 15, 2026. Within 24 hours of Jev's debut on Vercel's AI Gateway, the model reached 13% of paid teams—more than twice any previous model and six times the adoption rate of Fable 5.1.