---
title: "Code Runtime | Tarka Sandboxes"
description: "Python and Node sandboxes for short evals, code generation, and tool use."
url: "https://tarkahq.com/sandboxes/code-runtime/"
---

Sandbox type

# Code Runtime

Python and Node sandboxes for short evals, code generation, and tool use.

[Sign up](https://tarkahq.com/console?auth=signup) [Code Sandbox docs](https://tarkahq.com/docs/compute/sandboxes/code/)

- **Runtimes**: Python 3.12, Python 3.13, Node 22, Node 24
- **Dependencies**: uv (pyproject.toml), requirements.txt, package.json
- **CPU**: 1 vCPU
- **Memory**: 1 GiB
- **Direct egress**: Denied

## Overview

The most-requested sandbox type. Spin up a Python or Node process with a dependency-managed environment, run code, capture stdout/stderr/return values, and tear it down. Files are temporary for the sandbox lifetime and cannot be attached to a durable volume.

## Dependency manifests

Attach one of: `pyproject.toml`, `requirements.txt`, or `package.json`. Tarka rejects URL, git, local-path, custom-index, workspace, editable, and lifecycle-script sources. A template must reach the ready state before a sandbox can use it.

## Execution model

- **Sandbox lifetime**: 30–300 seconds, 300 seconds by default
- **Execution limit**: 1–30 seconds, 10 seconds by default
- **CPU**: fixed 1 vCPU
- **Memory**: fixed 1 GiB
- **Filesystem**: ephemeral and deleted with the sandbox
- **Network**: direct egress denied; approved HTTP(S) traffic uses a constrained proxy

## What we don’t allow

- Long-running daemons
- Shells, child processes, arbitrary commands, or user-supplied images
- Browsers, inbound ports, SSH, durable volumes, and GPUs
- Outbound network to private IP ranges (CGNAT, RFC1918) without allowlist
- Anything that would let one tenant see another’s process state