LangChain Sandbox alternatives
Because LangChain Sandbox is discontinued, teams are moving elsewhere. The 4 alternatives below are grouped by kind of sandbox, and each says what it does differently from LangChain Sandbox. Start from whatever made you look: missing GPUs, session limits, self-hosting, pricing or isolation.
Why teams look beyond LangChain Sandbox
LangChain has archived the langchain-sandbox repository and says the package is no longer maintained.
- No longer maintained; LangChain advises against production use
- No filesystem access; Python only; a few seconds of startup latency per run
- Security depends entirely on the Deno permissions you grant
LangChain Sandbox alternatives, by kind
Open-source runtimes to self-host
Open-source sandbox runtimes you run on your own servers or Kubernetes.
LLM Sandbox
Python library that runs model-generated code through one API on Docker, Podman or Kubernetes, with Bubblewrap/nsjail local backends and an MCP server.
- Docker/Podman/K8s container
- Open source
- Self-hostable
How it differs: Python applications that need to run model-generated code in whatever container runtime they already have. A convenient backend-agnostic wrapper for teams that already run containers and want a Python-first code-execution layer.
Isolation primitives and runtimes
The hypervisors, user-space kernels, OS sandboxes and WebAssembly runtimes that sandbox platforms build on.
just-bash
In-process bash reimplementation in TypeScript with a virtual filesystem, built by Vercel Labs so agents can run shell commands without touching the host.
- In-process interpreter
- Open source
- Self-hostable
How it differs: Giving an agent a bash-like tool over a virtual filesystem inside a Node.js process, for development, testing and lightweight file manipulation. Useful as an agent tool and test double, not as a security boundary for untrusted code.
Pyodide
CPython compiled to WebAssembly, with NumPy, pandas and SciPy ported, running Python inside the browser or Node.js sandbox.
- CPython in Wasm
- Open source
- Self-hostable
How it differs: Running short Python and data-science snippets in a browser tab or Node.js process without a server-side sandbox. The standard way to run Python in a browser or Node sandbox; ideal for short data bursts, unsuitable for anything needing an operating system.
Wasmtime
The Bytecode Alliance's standalone WebAssembly and WASI runtime, embeddable from Rust, C, Python, Go, .NET and Ruby, and the engine under Spin, Extism, Akamai Functions and Fastly.
- Wasm sandbox
- Open source
- Self-hostable
How it differs: Embedding a capability-based sandbox for plug-ins, functions and tool code inside your own application. The default WebAssembly engine for building a sandbox into your own software; choose it for plug-ins and tool code rather than whole-OS workloads.
LangChain Sandbox vs alternatives
| Sandbox | Isolation | Open source | Self-host / BYOC | Cold start (vendor) | Max session | Snapshots / pause | GPU | SDKs |
|---|---|---|---|---|---|---|---|---|
| LangChain Sandbox | Pyodide in Deno | Yes | Yes / No | a few seconds | Not documented | No / No | No | Python |
| just-bash | In-process interpreter | Yes | Yes / No | Not documented | Not documented | No / No | No | JavaScript/TypeScript |
| LLM Sandbox | Docker/Podman/K8s container | Yes | Yes / No | Not documented | Not documented | No / Not documented | Not documented | Python, MCP server |
| Pyodide | CPython in Wasm | Yes | Yes / No | Not documented | Not documented | No / No | No | JavaScript/TypeScript, Python |
| Wasmtime | Wasm sandbox | Yes | Yes / No | Not documented | Embedder-set | No / Not documented | No | CLI, Rust, C, C++, Python, .NET, Go, Ruby |
Frequently asked questions
What are the main alternatives to LangChain Sandbox?
Is there an open-source alternative to LangChain Sandbox?
Cite this page
Agent Sandboxes. (2026). LangChain Sandbox alternatives. agentsandboxes.org. Last reviewed November 9, 2026. https://agentsandboxes.org/alternatives/langchain-sandbox/
Found an error or a missing sandbox? Submit a correction — every entry links to the sources it relies on.