Arcbox

ArcBox's strongest claim is architectural honesty. Every Computer, Sandbox, and Runner is a virtual machine with its own kernel; the boundary is the hypervisor rather than a namespace or a permission prompt. If your agent writes and then executes its own code, that distinction is the whole product. The second-strongest claim is lifecycle: ready, exited, snapshotted, destroyed arrive as an event stream you subscribe to, so an agent knows the machine is up because the machine said so rather than because it polled. Combine that with snapshot-based warm creates — a fleet of identical machines is one snapshot away — and you get the scaling story agent platforms actually need. The three lifetimes map cleanly onto real work. Computers for stateful agents that should keep their disk between tasks (stopped machines keep the disk and are metered for storage only, no vCPU or memory until resumed). Sandboxes for untrusted code with a TTL and no minimum charge — a sandbox that runs four seconds costs four seconds. Runners for CI, one clean image per job. The unified verb surface (create, exec, snapshot, destroy) across CLI, Python, TypeScript, and REST means you are not maintaining three mental models. Weaknesses are mostly about access and pricing shape. Linux and Windows open in waves via waitlist; macOS, iOS, and Android are quoted with sales, with iOS available only as long-lived Computers (no disposable form) and Android CI runners not offered at all. No GPU option is published, so training or GPU-bound inference is not a fit. Metered per-second billing is excellent for bursty agent loads and awkward for budget planners who want a flat monthly number. Apple pricing is per dedicated host-hour or environment-hour with a 24-hour minimum lease, which makes short experiments on macOS expensive relative to Linux. And if you need production capacity this week, the waitlist is a real blocker rather than a formality. Where it fits: agentic platforms executing untrusted or self-generated code, red teams containing exploitable binaries, and CI pipelines that want a clean VM per job. Also of note for Mac developers — ArcBox Desktop is a public beta, open-source Docker Desktop alternative, and the team publishes its measurements, including a benchmark showing Apple's balloon device does not release pages host-side in Linux VMs, which Docker, Podman, and OrbStack are all working around.