Back Engineering September 16, 2025•15 minute read👋 Hi, I’m Eric. I work on systems and product at Modal. We recently launched Modal Notebooks, a new cloud Jupyter notebook that boots GPUs and arbitrary custom images in seconds, all with real-time collaboration. I want to share some of the engineering that made this experience possible. This post isn’t about features, but about the systems work behind running interactive, high-performance GPU workloads in the cloud while still feeling instantan...