Zeroboot VM Sandbox

Skill by ara.so — Daily 2026 Skills collection.

Zeroboot provides sub-millisecond KVM virtual machine sandboxes for AI agents using copy-on-write forking. Each sandbox is a real hardware-isolated VM (via Firecracker + KVM), not a container. A template VM is snapshotted once, then forked in ~0.8ms per execution using mmap(MAP_PRIVATE) CoW semantics.

How It Works

Firecracker snapshot ──► mmap(MAP_PRIVATE) ──► KVM VM + restored CPU state
                           (copy-on-write)          (~0.8ms)

1. Template: Firecracker boots once, pre-loads your runtime, snapshots memory + CPU state
2. Fork (~0.8ms): New KVM VM maps snapshot memory as CoW, restores CPU state
3. Isolation: Each fork is a separate KVM VM with hardware-enforced memory isolation

Installation