Best sandboxes for local coding agents
For local coding agents, our top picks are Docker Sandboxes, Microsandbox and Anthropic Sandbox Runtime. We weight isolation strength, filesystem and network controls, and friction on a developer machine.
What local coding agents need from a sandbox
Coding agents such as Claude Code, Codex or Gemini CLI often run on a developer’s laptop with access to their files and credentials. A local sandbox should:
- Restrict filesystem writes to the project.
- Enforce deny-by-default network with an allowlist.
- Keep credentials out of the agent’s reach where possible.
- Add little friction, so developers actually use it.
Best sandboxes for local coding agents, ranked
Docker Sandboxes
Docker’s `sbx` CLI for running AI coding agents in microVM sandboxes on your machine, with an experimental Docker-hosted cloud.
- MicroVM
- Self-hostable
- GPU
- Pause/resume
Why it’s here: A microVM per agent with its own Docker Engine, deny-by-default networking and host-side credential injection; templates for popular coding agents; free locally.
Microsandbox
Open-source, local-first microVM runtime that gives each sandbox its own Linux kernel, with an optional managed cloud.
- MicroVM (libkrun)
- Open source
- Self-hostable
- BYOC
- Snapshots
Why it’s here: Open-source microVMs on macOS, Linux and Windows with network policy and placeholder secrets.
Anthropic Sandbox Runtime
Open-source CLI and library (`srt`) that restricts filesystem and network access for any local process at the OS level, without a container or VM.
- OS-level (Seatbelt / bubblewrap)
- Open source
- Self-hostable
Why it’s here: Near-zero-overhead OS-level sandbox (Seatbelt/bubblewrap) with a deny-by-default network proxy; weaker boundary than a VM.
Side by side
| Sandbox | Isolation | Open source | Self-host / BYOC | Cold start (vendor) | Max session | Snapshots / pause | GPU | SDKs |
|---|---|---|---|---|---|---|---|---|
| Docker Sandboxes | MicroVM | No | Yes / No | Not documented | Until removed (local) | Yes / Yes | Yes | sbx CLI, TypeScript (cloud), REST API (cloud) |
| Microsandbox | MicroVM (libkrun) | Yes | Yes / Yes | <100 ms | Not documented | Yes / Not documented | No | TypeScript, Python, Rust, Go, Ruby, CLI, MCP server |
| Anthropic Sandbox Runtime | OS-level (Seatbelt / bubblewrap) | Yes | Yes / Not documented | Process start | Not documented | No / No | Not documented | CLI (srt), TypeScript (npm) |
Frequently asked questions
How do I sandbox Claude Code or Codex on my laptop?
Cite this page
Agent Sandboxes. (2026). Best sandboxes for local coding agents. agentsandboxes.org. Last reviewed November 8, 2026. https://agentsandboxes.org/best/local-agents/
Found an error or a missing sandbox? Submit a correction — every entry links to the sources it relies on.