The VMs Powering Mobile Agents (Instinct, Claude Code)

Claude Code utilizes Firecracker microVMs with a custom 6.18.5-fc-v2 kernel and a Rust-based process_api as PID 1. The architecture uses a 324 MB read-only Bun harness to execute tool calls, while persistent user data is stored on a separate writable vda disk. Sessions leverage vsock for host communication and maintain continuity by reattaching disks after idle reclaim.