Secure Node.js Execution Without a Sandbox

A lightweight library for secure Node.js execution.
No containers, no VMs — just npm-compatible sandboxing out of the box.
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Give your AI agent secure code execution

Expose secure-exec as a tool with the Vercel AI SDK. Your agent can execute arbitrary code without risking your infrastructure.

agent.ts

import { generateText, tool } from "ai";
import { anthropic } from "@ai-sdk/anthropic";
import { NodeRuntime, createNodeDriver, createNodeRuntimeDriverFactory } from "secure-exec";
import { z } from "zod";

// Create a sandboxed runtime
const runtime = new NodeRuntime({
  systemDriver: createNodeDriver({ permissions: { fs: true, network: true } }),
  runtimeDriverFactory: createNodeRuntimeDriverFactory(),
  memoryLimit: 64,
  cpuTimeLimitMs: 5000,
});

// Expose as an AI SDK tool
const result = await generateText({
  model: anthropic("claude-sonnet-4-20250514"),
  tools: {
    execute: tool({
      description: "Run JavaScript in a secure sandbox",
      parameters: z.object({ code: z.string() }),
      execute: async ({ code }) => {
        const logs: string[] = [];
        const res = await runtime.exec(code, {
          onStdio: (e) => logs.push(e.message),
        });
        return { exitCode: res.code, output: logs.join("\\n") };
      },
    }),
  },
  prompt: "Calculate the first 20 fibonacci numbers",
});

Why Secure Exec

Give your AI agent the ability to write and run code safely. Works with the Vercel AI SDK, LangChain, and any tool-use framework.

No infrastructure required

No Docker daemon, no hypervisor, no orchestrator. Runs anywhere Node.js, Bun, or an HTML5 browser runs. Deploy to Lambda, a VPS, or a static site — your existing deployment works.

Node.js & npm compatibility

fs, child_process, http, dns, process, os — bridged to real host capabilities, not stubbed. Run Express, Hono, Next.js, and any npm package.

Compatibility matrix →

Built for AI agents

Give your AI agent the ability to write and run code safely. Works with the Vercel AI SDK, LangChain, and any tool-use framework.

Deny-by-default permissions

Filesystem, network, child processes, and env vars are all blocked unless explicitly allowed. Permissions are composable functions — grant read but not write, allow fetch but block spawn.

Configurable resource limits

CPU time budgets and memory caps. Runaway code is terminated deterministically with exit code 124 — no OOM crashes, no infinite loops, no host exhaustion.

Powered by V8 isolates

The same isolation primitive behind Cloudflare Workers for Platforms and every browser tab. Battle-tested at scale by the infrastructure you already trust.

Benchmarks

V8 isolates vs. container-based sandboxes.

Cold startTime to interactive (TTI). Sandbox values use the fastest provider — e2b (best median) from ComputeSDK as of March 2026. Secure Exec measured over 100 iterations × 100 samples. Our benchmarks →

Lower is better

Secure Exec

17.9 ms176x faster

Fastest sandbox

3,150 ms

Memory per instanceSecure Exec memory is the converged at-scale average per execution. Sandbox value uses the smallest minimum among popular providers (e2b, Daytona, Modal, Cloudflare) as of March 2026 — 256 MB for Modal and Cloudflare. Our benchmarks →

Lower is better

Secure Exec

~3.4 MB75x smaller

Sandbox provider minimum

~256 MB

Cost per execution-secondSandbox value uses the cheapest provider — Cloudflare Containers (256 MB min, billed per second at $0.0000025/GiB·s) as of March 2026. Secure Exec: 3.4 MB baseline (p95) with 30% empty capacity assumed across self-hosted hardware tiers. Our benchmarks → · Full cost breakdown →

Lower is better

Secure Exec

$0.000011/s56x cheaper

Cheapest sandbox

$0.000625/s

Sandbox provider numbers based on published documentation and benchmarks. Secure Exec measured on Intel i7-12700KF, Node.js v24. Methodology → · Cost breakdown →