Run code once

Use kumoba run when you want an answer, not a machine: it creates a sandbox, runs one command, prints its output and deletes the sandbox. Nothing is left behind.

Before you begin, install kumoba and start kumobad.

1. Run a command:

   kumoba run -- python3 -c 'print("hello from a fresh VM")'

   Everything after -- is the program and its arguments. A bare name such as python3 is looked up on the guest's PATH.

2. Check the exit status. kumoba run exits with the command's own status, so scripts and agents can branch on it:

   kumoba run -- sh -c 'exit 7'; echo $?      # 7

Run without network access

By default a sandbox can reach the public internet. To run untrusted code with no network at all:

kumoba run --network.mode blocked -- python3 untrusted.py

To allow only some hosts, list them. *.example.com matches subdomains:

kumoba run --network.mode allowlist --network.hosts example.com -- curl -sS https://example.com

Limit time and resources

kumoba run --timeout-ms 30000 --cpu 1 --memory-mib 1024 -- python3 job.py

A command that runs past its timeout is killed and kumoba run exits with status 124.

From code

import { Kumoba } from "kumoba";

const result = await new Kumoba().run("python3 --version");
console.log(result.exitCode, result.stdout);

Next steps

• To keep a sandbox between commands, see Work in a sandbox.
• For every option, run kumoba run --help or see the CLI reference.