amla-sandbox

This repository is the release source for the amla-sandbox Python package. Development happens in the amlalabs monorepo; this repo is updated on release. The Rust runtime that compiles to amla_sandbox.wasm lives in amla-sandbox-core; the exact release tag this Python package was built against is recorded in .mirror-deps.json.

amla-sandbox is a WASM sandbox with capability enforcement for AI agent code. Agents can only call tools you explicitly provide, with constraints you define. Sandboxed virtual filesystem. No network. No shell escape.

Install

pip install amla-sandbox

No Docker. No VM. One binary, works everywhere.

Quick start

from amla_sandbox import create_sandbox_tool

sandbox = create_sandbox_tool()

# JavaScript
sandbox.run("console.log('hello'.toUpperCase())", language="javascript")
# Shell
sandbox.run("echo 'hello' | tr 'a-z' 'A-Z'", language="shell")

# With tools
def get_weather(city: str) -> dict:
    return {"city": city, "temp": 72}

sandbox = create_sandbox_tool(tools=[get_weather])
sandbox.run(
    "const w = await get_weather({city: 'SF'}); console.log(w);",
    language="javascript",
)

With capability constraints:

from amla_sandbox import Sandbox, ToolCallCap, ConstraintSet, Param

sandbox = Sandbox(
    capabilities=[
        ToolCallCap(
            method_pattern="stripe/charges/*",
            constraints=ConstraintSet([
                Param("amount") <= 10000,
                Param("currency").is_in(["USD", "EUR"]),
            ]),
            max_calls=100,
        ),
    ],
    tool_handler=my_handler,
)

See the PyPI page and the examples/ directory for the full API surface, framework integrations, and the constraint DSL.

Security model

The sandbox runs inside WebAssembly with WASI for a minimal syscall surface. On top of WASM isolation, every tool call goes through capability validation; access is explicitly granted, not implicitly available. See the Quick start above and the upstream PyPI README for the full explanation and tradeoffs.

Building from source

For most users, installing from PyPI is recommended; the wheel includes the prebuilt WASM binary. If you want to build the wheel yourself:

uv build

To regenerate the WASM artifact bundled inside the wheel, build it from amla-sandbox-core at the tag pinned in .mirror-deps.json, then drop the result at src/amla_sandbox/_wasm/amla_sandbox.wasm before running uv build.

Contributing

See CONTRIBUTING.md. Pull requests against this mirror will be clobbered on next release; please target the monorepo or open an issue here.

License

Python package code is MIT licensed. The bundled Rust WASM runtime is AGPL-3.0-or-later OR BUSL-1.1.