Lightpanda — Headless Browser for AI & Automation

Skill by ara.so — Daily 2026 Skills collection

Lightpanda is a headless browser built from scratch in Zig, designed for AI agents, web scraping, and automation. It uses 9x less memory and runs 11x faster than Chrome headless.

Key facts:

• Not based on Chromium, Blink, or WebKit — clean-slate Zig implementation

• JavaScript execution via V8 engine

• CDP (Chrome DevTools Protocol) compatible — works with Playwright, Puppeteer, chromedp

• Respects robots.txt via --obey_robots flag

• Beta status, actively developed

• License: AGPL-3.0

Installation

macOS (Apple Silicon)

curl -L -o lightpanda https://github.com/lightpanda-io/browser/releases/download/nightly/lightpanda-aarch64-macos chmod a+x ./lightpanda

Linux (x86_64)

curl -L -o lightpanda https://github.com/lightpanda-io/browser/releases/download/nightly/lightpanda-x86_64-linux chmod a+x ./lightpanda

Docker

Supports amd64 and arm64

docker run -d --name lightpanda -p 9222:9222 lightpanda/browser:nightly

CLI Usage

Fetch a URL (dump rendered HTML)

./lightpanda fetch --obey_robots --log_format pretty --log_level info https://example.com

Start CDP Server

./lightpanda serve --obey_robots --log_format pretty --log_level info --host 127.0.0.1 --port 9222

This launches a WebSocket-based CDP server for programmatic control.

CLI Flags

Flag Description

--obey_robots

Respect robots.txt rules

--log_format pretty

Human-readable log output

--log_level info

Log verbosity: debug , info , warn , error

--host 127.0.0.1

Bind address for CDP server

--port 9222

Port for CDP server

--insecure_disable_tls_host_verification

Disable TLS verification (testing only)

Playwright Integration

Start the CDP server, then connect Playwright to it:

import { chromium } from 'playwright-core';

const browser = await chromium.connectOverCDP('http://127.0.0.1:9222'); const context = await browser.contexts()[0] || await browser.newContext(); const page = await context.newPage();

await page.goto('https://example.com', { waitUntil: 'networkidle' }); const title = await page.title(); const content = await page.content();

console.log(Title: ${title}); console.log(HTML length: ${content.length});

await browser.close();

Puppeteer Integration

import puppeteer from 'puppeteer-core';

const browser = await puppeteer.connect({ browserWSEndpoint: 'ws://127.0.0.1:9222', });

const context = await browser.createBrowserContext(); const page = await context.newPage();

await page.goto('https://example.com', { waitUntil: 'networkidle0' });

const title = await page.title(); const text = await page.evaluate(() => document.body.innerText);

console.log(Title: ${title}); console.log(Body text: ${text.substring(0, 200)});

await page.close(); await browser.close();

Go (chromedp) Integration

package main

import ( "context" "fmt" "log"

"github.com/chromedp/chromedp"

)

func main() { allocCtx, cancel := chromedp.NewRemoteAllocator(context.Background(), "ws://127.0.0.1:9222") defer cancel()

ctx, cancel := chromedp.NewContext(allocCtx)
defer cancel()

var title string
err := chromedp.Run(ctx,
    chromedp.Navigate("https://example.com"),
    chromedp.Title(&title),
)
if err != nil {
    log.Fatal(err)
}
fmt.Println("Title:", title)

}

Python Integration

import asyncio from playwright.async_api import async_playwright

async def main(): async with async_playwright() as p: browser = await p.chromium.connect_over_cdp("http://127.0.0.1:9222") context = browser.contexts[0] if browser.contexts else await browser.new_context() page = await context.new_page()

    await page.goto("https://example.com", wait_until="networkidle")
    title = await page.title()
    content = await page.content()

    print(f"Title: {title}")
    print(f"HTML length: {len(content)}")

    await browser.close()

asyncio.run(main())

Web Scraping Patterns

Batch Page Fetching

import { chromium } from 'playwright-core';

const browser = await chromium.connectOverCDP('http://127.0.0.1:9222'); const context = await browser.newContext();

const urls = [ 'https://example.com/page1', 'https://example.com/page2', 'https://example.com/page3', ];

for (const url of urls) { const page = await context.newPage(); await page.goto(url, { waitUntil: 'networkidle' });

const data = await page.evaluate(() => ({ title: document.title, text: document.body.innerText, links: [...document.querySelectorAll('a[href]')].map(a => a.href), }));

console.log(JSON.stringify(data, null, 2)); await page.close(); }

await browser.close();

Extract Structured Data

const data = await page.evaluate(() => { const items = document.querySelectorAll('.product-card'); return [...items].map(item => ({ name: item.querySelector('h2')?.textContent?.trim(), price: item.querySelector('.price')?.textContent?.trim(), link: item.querySelector('a')?.href, })); });

Docker Compose (with your app)

services: lightpanda: image: lightpanda/browser:nightly ports: - "9222:9222" restart: unless-stopped

scraper: build: . depends_on: - lightpanda environment: - BROWSER_WS_ENDPOINT=ws://lightpanda:9222

Supported Web APIs

Lightpanda supports (partial, expanding):

• DOM tree manipulation and querying

• JavaScript execution (V8)

• XMLHttpRequest (XHR)

• Fetch API

• Cookie management

• Network interception

• Proxy support

Configuration

Environment Variable Description

LIGHTPANDA_DISABLE_TELEMETRY

Set to true to opt out of usage metrics

Performance Comparison

Metric Lightpanda Chrome Headless

Memory ~9x less Baseline

Speed ~11x faster Baseline

Binary size Small (Zig) Large (Chromium)

Rendering No visual rendering Full rendering engine

When to Use Lightpanda

Use Lightpanda when:

• Running AI agents that need to browse the web

• Batch scraping at scale (memory/CPU savings matter)

• Automating form submissions and data extraction

• Running in containers where resources are limited

• You need CDP compatibility but not full visual rendering

Use Chrome/Playwright instead when:

• You need pixel-perfect screenshots or PDF generation

• You need full Web API coverage (Lightpanda is still partial)

• Visual regression testing

• Testing browser-specific rendering behavior

Building from Source

Requires: Zig 0.15.2, Rust, CMake, system dependencies.

Ubuntu/Debian dependencies

sudo apt install xz-utils ca-certificates pkg-config libglib2.0-dev clang make curl

Build

git clone https://github.com/lightpanda-io/browser.git cd browser zig build

Optional: pre-build V8 snapshot for faster startup

zig build snapshot_creator -- src/snapshot.bin zig build -Dsnapshot_path=../../snapshot.bin

Troubleshooting

Connection refused on port 9222:

• Ensure ./lightpanda serve is running

• Check --host 0.0.0.0 if connecting from Docker/remote

Playwright script breaks after update:

• Lightpanda is beta — Playwright's capability detection may behave differently across versions

• Pin your Lightpanda version or use nightly consistently

Missing Web API support:

• Check the zig-js-runtime repo for current API coverage

• File issues at lightpanda-io/browser

Links

• GitHub: https://github.com/lightpanda-io/browser

• Runtime APIs: https://github.com/lightpanda-io/zig-js-runtime