OpenAI's Codex coding application, now powered by GPT-5.5, runs on NVIDIA's GB200 NVL72 rack-scale systems, delivering dramatically faster and cheaper AI inference. Over 10,000 NVIDIA employees across various departments are already using it, reporting significant productivity gains such as debugging cycles shrinking from days to hours and weeks-long projects completing overnight. The rollout reflects a decade-long partnership between NVIDIA and OpenAI, with OpenAI committing to deploy over 10 gigawatts of NVIDIA systems for future AI infrastructure.