On July 15, Perplexity launched SPACE, the sandbox platform that now runs underneath Computer, its agent platform for knowledge work. Nate Kupp, Perplexity’s vice president of infrastructure, told The New Stack that the real engineering went into managing state—pausing, resuming, and forking agent sessions that can sometimes run for days or weeks—across millions of sandboxes. Kupp said the team wanted agents “to pause and resume and run tasks for not just hours but then days and weeks,” with sessions living on as persistent, durable artifacts. SPACE uses Firecracker as its core building block and Kubernetes for cloud deployments, with portability across environments as a design goal. Most work sat in the control plane above these microVMs. The foundation for pause, resume, snapshot, and fork operations turned out to be Btrfs, the Linux copy-on-write filesystem, which makes snapshots and forks cheap metadata operations. On top of that sit rolling snapshots of full session state, live memory included, occurring as often as every minute.