Reactor

Reactor provides hosted infrastructure for developers building real-time generative video and interactive world-model applications. Its SDK and API handle deployment and streaming so developers can build experiences that respond to user input during generation. The model catalog spans explorable environments, streaming video editing and talking avatars: LTX generates synchronized voice and lip-synced video, while Happy Oyster generates worlds frame by frame as users move. The infrastructure maintains state across interactions and coordinates continuous, bidirectional video sessions.

Founded in 2025 by CEO Alberto Taiuti and CTO Bryce Schmidtchen, Reactor draws on their work as technical leads on Apple Vision Pro. Taiuti previously co-founded Luma AI and served as its CTO. Reactor also supported research reproducing Dreamer4, with a released world model and training code. That work documents how to train visual tokenizers and dynamics models, improve GPU utilization and address training instability; the resulting model can be explored through Reactor’s runtime.

Reactor charges by usage and model type, placing its business between model developers and application builders. Overworld uses its infrastructure to support interactive world-model development. In 2026, Reactor emerged from stealth with $59 million in combined Seed and Series A funding; Lightspeed co-led the Seed and led the Series A.