What Is Sandboxer? Cloud Sandboxes for AI Agents

What does Sandboxer do?

Sandboxer creates isolated virtual machines on demand. You ask for one from the sbx command line, the REST API, an SDK or an MCP client, and a few moments later you have a machine that an agent can treat as its own. It can install packages, run Docker, start servers and keep working for hours or days.

Everything goes through one REST API at https://sandboxer.com/api/v1, described by an OpenAPI document. The sbx CLI, the TypeScript and Python SDKs and the MCP server all sit on top of it, so the same sandbox can be driven from a terminal, a backend or a chat with Claude.

The product is built by North Bay Ventures, a venture studio. This hub collects plain-English explainers about how Sandboxer works. For the official reference, read the Sandboxer docs.

What is inside each sandbox?

Every sandbox is the same kind of machine, whatever its size. According to the machines page, each one has:

Ubuntu 24.04 running on its own kernel under Cloud Hypervisor, not a container
A normal user with passwordless sudo, plus systemd for services
Docker with BuildKit and Compose, and /dev/kvm for nested virtualization
SSH and SCP, a public IPv6 address, and an HTTPS URL for any port you choose to publish
A streamed desktop with Google Chrome
Coding agents already installed: Claude Code, Codex, OpenCode, Pi, Kimi Code and Mistral Vibe

What makes it different from a short-lived code runner?

Sandboxer is designed for long, stateful work rather than one quick function call. Three features carry most of that:

Feature	What it means
Stop with memory	A stop saves memory as well as disk, so processes are still running after a resume. See pause and resume.
Copy-on-write forks	A fork copies a sandbox's disk into a new, independent sandbox. See forking.
Per-second billing	You pay while a sandbox runs and nothing while it is stopped. See pricing.

Idle sandboxes can also pause themselves and wake on the next request, so a forgotten machine does not keep billing.

Who is Sandboxer for?

Sandboxer fits teams whose agents need a whole Linux machine. Typical uses on the site include running coding agents in parallel, executing model-written code, per-pull-request preview environments, computer-use agents on a desktop, and the Android emulator through nested KVM.

The site is also clear about where it does not fit. There are no GPUs, there are two regions, and there is no SLA during early access. If you need any of those today, another service may suit you better.

How do I try it?

Install the CLI, sign in, and create a sandbox. There's no free trial: plans start at $20/month, charged when you subscribe, and signing up and the docs need no card.

curl -fsSL https://sandboxer.com/install | sh
sbx new
sbx ssh

The getting started guide walks through each step.

Which Sandboxer explainers are on this site?

Each page below answers one question in plain English and links to the matching page on sandboxer.com.

Frequently asked questions

Is Sandboxer a container platform?

No. Each sandbox is a full virtual machine with its own kernel, running under Cloud Hypervisor.

Who makes Sandboxer?

Sandboxer is operated by North Bay Opco I, Inc., a Delaware corporation, and built by the North Bay Ventures studio.

Does Sandboxer offer GPUs?

No. Sandboxer's own site states it has no GPUs, so GPU work belongs elsewhere.

Where does Sandboxer run?

On dedicated servers in two regions: US East in Ashburn, Virginia, and EU Central in Helsinki, Finland.