DeepSeek DSec: 3M agent sandboxes/day, 380K concurrent on 160 nodes

DeepSeek’s DSec paper (arXiv 2609.22978) details a production sandbox platform—FnCall, containers, Firecracker microVMs, and full VMs via one SDK—serving ~3M instances/day and 380K concurrent from ~160 nodes, with on-demand EROFS images and pause/resume tied to GPU preemption. The platform itself isn’t released; its OverlayBD/ublk storage bits live in MIT-licensed AgentENV (kvcache-ai), the Firecracker stack behind Kimi K3.