ArcBox is a container and virtual machine runtime for macOS, written from scratch in Rust and positioned as an open-source alternative to Docker Desktop and OrbStack. One daemon and one CLI run four kinds of workload on the same runtime, all locally on the Mac, without a platform account or cloud control plane.
| Tier | What it is |
|---|---|
| Containers | A drop-in Docker engine, plus native Kubernetes |
| Sandboxes | Disposable microVMs for AI agents and untrusted code |
| Linux machines | Full VMs with their own kernel, disk, and distro |
| macOS guests | Throwaway macOS VMs, cloned from a base image |
For agents, sandboxes are disposable microVMs, each with its own kernel, booted by Firecracker nested inside the guest. A built-in command builds a sandbox from a template and attaches your terminal to Claude Code inside it with the agent's permission prompts switched off, since the microVM is the isolation boundary. Nothing on the host is mounted into the sandbox. Sandboxes can be built from templates, Docker images, or Dockerfiles, and snapshotted when idle so the next one skips a cold boot. Every CLI action is a gRPC call on the daemon socket, so SDKs and your own tooling can drive sandboxes directly. Sandboxes need nested virtualization, which means an Apple Silicon M3 or newer.
The runtime carries its own hypervisor backend on Hypervisor.framework alongside a Virtualization.framework backend, its own VirtIO devices, a userspace network datapath with local name resolution for containers and machines, and VirtioFS filesystem sharing. FEX translates x86-64 so amd64 images run on Apple Silicon. A native SwiftUI desktop app covers Docker and Kubernetes resources, logs, a terminal, resource monitoring, and a file browser. The project is in public beta, and a hosted Agent Computer platform offering persistent computers, sandboxes, and CI runners across several operating systems is on a waitlist.
Features
- Drop-in Docker engine: a Docker-compatible socket that works with the Docker CLI, Compose, BuildKit, port forwarding, bind mounts, and volumes
- Native Kubernetes: a daemon-managed local k3s cluster with kubectl integration and LoadBalancer services reachable on the Mac
- Agent sandboxes: disposable Firecracker microVMs with their own kernel for AI agents, untrusted code, and CI jobs
- Claude Code in a sandbox: one command builds a sandbox and attaches your terminal to Claude Code running inside it
- Sandbox snapshots: checkpoint a booted, idle sandbox and restore new sandboxes from it with near-zero boot
- gRPC API: every operation (create, exec, file transfer, port exposure, lifecycle events, snapshots) is callable from SDKs
- Linux machines: full VMs for Alpine, Arch Linux, Debian, Fedora, and Ubuntu, with copy-on-write clones and single-file export
- macOS guests: throwaway macOS VMs cloned copy-on-write from a published base image
- Finder access: container data and running machines' filesystems are browsable from the Mac
- x86 translation: amd64 images run on Apple Silicon through the FEX emulator
- Migration: imports images, volumes, networks, and containers from Docker Desktop or OrbStack
- Desktop app: a native SwiftUI app for containers, images, volumes, networks, pods, services, logs, and live resource usage
