Trajectory launches self-serve platform for post-training AI models on production data

The Sequoia-backed startup wants companies to turn everyday user edits and corrections into weekly model upgrades Trajectory, a startup built by former researchers from Google DeepMind, OpenAI and Apple, has opened a self-serve platform for post-training AI models on real production data. The pitch is simple. Every time a user fixes an AI’s output, that correction becomes training material instead of wasted effort. The platform went live on November 2, 2026. It moves Trajectory from a company that worked closely with a handful of partners to one that any qualifying business can sign up for and start using. What Trajectory actually built The mechanics run through a lightweight software development kit, or SDK. Companies plug it into their products, and it captures usage signals such as edits and corrections that users make to AI-generated output. Those signals then feed post-training cycles. Post-training is the refinement stage that happens after a model’s initial training, where it gets tuned for specific behavior or tasks. According to the company’s materials, those cycles can run on a weekly basis or more frequently. Trajectory also offers a feature it calls continual grading, d...