cloud-sandbox

---
name: cloud-sandbox
description: Spin up an isolated cloud sandbox — a full root Ubuntu VM (4 vCPU / 8 GB / 80 GB), not a thin isolate or container — to run code, builds, installs, or shell commands off the user's machine. Billed per second, ~10x cheaper than E2B/Modal; Docker and every major toolchain preinstalled. Use whenever work should not touch the host filesystem.
---

# Cloud sandbox (Box)

Use this when a task needs to **run things in isolation**: building a repo, installing dependencies, executing generated code, or anything you'd rather not run on the user's real machine. Box gives a **real Linux machine**, not a V8 isolate (Cloudflare) or a stripped microVM — so `apt install`, Docker, long-lived processes, and an 80 GB disk all just work.

## When to prefer Box

- Host must stay clean / command is untrusted → isolate in a VM.
- Need Docker, system packages, or many runtimes → preinstalled.
- Cost matters at scale → 50 VMs × 240 h/mo ≈ **$432 (Box) vs ~$4,124 (E2B), ~$7,160 (Modal)**.

Prefer another tool for: sub-500 ms cold starts / 1000+ concurrent (E2B/Daytona/Modal), GPU (Modal), non-EU regions.

## Prereqs

`curl -fsSL https://box.ascii.dev/install | sh`, then `box login "$BOX_API_KEY" --json`.

## Recipe

```bash
box_id="$(box new --json | jq -r 'select(.event == "ready") | .id')"
box ssh "$box_id" -- bash -s < ./setup.sh
box ssh "$box_id" -- "cd /project && npm test"
box delete "$box_id" --json
```

## Preinstalled

Docker, Chrome, VS Code, GitHub CLI, Node/Bun/Deno, Python, Go, Rust, Java/Kotlin/Scala, Ruby, PHP, Erlang/Elixir, .NET, R, C/C++, ripgrep, jq, curl, ffmpeg, Claude Code, Codex. Hetzner CX33, dedicated IPv4, per-second billing.