OpenSandbox
Open SourceSecure, fast, and extensible sandbox runtime for AI agents.
Published 2 October 2026
Scores
Popularity2/5
About 15.6K GitHub stars since its March 2026 release, close to E2B's count, but it is not among the OpenAI Agents SDK's built-in providers and comes up far less often in sandbox comparisons than E2B or Daytona.
Learning Curve3/5
A local Docker sandbox and a few SDK calls are quick to set up, but a production deployment means configuring Kubernetes, an isolation runtime, and network policies yourself.
Flexibility5/5
Three isolation backends, Docker and Kubernetes runtimes, five SDK languages, and ready-made environments for code, browsers, desktops, and RL training cover almost any agent workload.
Performance4/5
Firecracker sandboxes start in around 100 milliseconds and pause with state intact, while the gVisor path trades some startup and syscall speed for its isolation.
Portability5/5
Apache-2.0, runs on any Docker host or Kubernetes cluster in any cloud or on-premises, and depends on no vendor service.
About OpenSandbox
OpenSandbox is an open-source sandbox runtime for AI agents, released by Alibaba in March 2026 under the Apache-2.0 license. It gives an agent an isolated environment to run the commands and code it writes, edit files, drive a browser, or operate a full desktop, without access to the host it runs on. It is listed on the CNCF Landscape and gathered thousands of GitHub stars in its first days.
The defining trait is that it is self-hosted from the start. The same sandbox lifecycle API runs on a developer's machine through Docker and in production on Kubernetes, so a team keeps agent workloads, data, and network traffic inside its own infrastructure. Isolation goes beyond plain containers: sandboxes can run under gVisor, Kata Containers, or Firecracker microVMs, and the Firecracker mode starts sandboxes in around 100 milliseconds and can pause and resume them with memory and disk intact. Per-sandbox egress policies, an ingress gateway, and a credential vault control what an agent can reach and which secrets it can use.
Developers work with it through SDKs for Python, Java and Kotlin, JavaScript and TypeScript, C#, and Go, the osb command-line tool, and an MCP server that lets Claude Code or Cursor create sandboxes directly. Ready-made environments cover coding agents, browser automation with Playwright and Chrome, VNC desktops for GUI agents, data analysis, agent evaluation, and reinforcement-learning training, with integrations for Claude Code, Gemini CLI, Codex, LangGraph, and Google ADK.
There is no hosted service: OpenSandbox is free software, and its cost is the infrastructure it runs on and the work of operating it.
Key Features
- Self-hosted on Docker locally or Kubernetes in production
- gVisor, Kata Containers, or Firecracker microVM isolation
- Firecracker sandboxes start in about 100 ms, with pause and resume
- SDKs for Python, Java and Kotlin, JavaScript and TypeScript, C#, and Go
- osb CLI and an MCP server for Claude Code and Cursor
- Browser, VNC desktop, and VS Code environments for GUI and coding agents
- Per-sandbox egress policies and a credential vault
Pros
- Fully open source and self-hosted, so agent code and data never leave the team's own infrastructure
- Choice of isolation backends lets teams trade startup speed against security per workload
- SDKs in five languages, including Java and C#, which most sandbox vendors skip
- No usage bills: the only cost is the compute it runs on
Cons
- Running it in production means operating a Kubernetes deployment, unlike the one-call managed sandboxes of E2B or Modal
- Young project, so documentation, examples, and community answers are thinner than for E2B
- No managed cloud option for teams that want sandboxes without the operations work
- Stronger isolation backends such as Firecracker and Kata need host support for virtualization
OpenSandbox Pricing
Open SourceTools Related to OpenSandbox
Works well with OpenSandbox(1)
OpenSandbox's local runtime starts each sandbox as a container on the Docker daemon from any OCI image, so a laptop with Docker is enough to develop against the same API used in production.
Integrates with OpenSandbox(1)
OpenSandbox ships a Kubernetes operator and Helm charts: in production each sandbox runs as a pod managed through custom resources, with resource pools for fast batch creation.
Alternatives to OpenSandbox(3)
OpenSandbox is Apache-2.0 software you deploy on your own Docker host or Kubernetes cluster; Daytona is a closed-source managed service with fast-starting sandboxes that persist without a time limit. Pick OpenSandbox for self-hosting and data control, Daytona for a hosted sandbox with no cluster to run.
OpenSandbox is free and runs only on infrastructure you operate, on Docker or Kubernetes, with a choice of gVisor, Kata, or Firecracker isolation; E2B is a managed service that starts Firecracker microVM sandboxes with one API call and can also be self-hosted. Pick OpenSandbox to keep agent workloads in-house, E2B to skip the operations work.
OpenSandbox is a self-hosted sandbox runtime for Docker and Kubernetes with no usage fees; Modal runs sandboxes in gVisor containers on a managed serverless platform that also offers GPUs and inference endpoints. Pick OpenSandbox to run sandboxes inside your own infrastructure, Modal to rent them by the second.
Vendor
Alibaba Cloud
Website →Tags
Details
- Maintained
- Yes