<p align="center">
  <a href="https://lightpanda.io"><img src="https://cdn.lightpanda.io/assets/images/logo/lpd-logo.png" alt="Logo" height=170></a>
</p>
<h1 align="center">Lightpanda Browser</h1>
<p align="center">
<strong>The headless browser built from scratch for AI agents and automation.</strong><br>
Not a Chromium fork. Not a WebKit patch. A new browser, written in Zig.
</p>

</div>
<div align="center">

[![License](https://img.shields.io/github/license/lightpanda-io/browser)](https://github.com/lightpanda-io/browser/blob/main/LICENSE)
[![Twitter Follow](https://img.shields.io/twitter/follow/lightpanda_io)](https://twitter.com/lightpanda_io)
[![GitHub stars](https://img.shields.io/github/stars/lightpanda-io/browser)](https://github.com/lightpanda-io/browser)
[![Discord](https://img.shields.io/discord/1391984864894521354?style=flat-square&label=discord)](https://discord.gg/K63XeymfB5)

</div>
<div align="center">

[<img width="350px" src="https://cdn.lightpanda.io/assets/images/github/execution-time-v2.svg">
](https://github.com/lightpanda-io/demo)
&emsp;
[<img width="350px" src="https://cdn.lightpanda.io/assets/images/github/memory-frame-v2.svg">
](https://github.com/lightpanda-io/demo)
</div>

_chromedp requesting 933 real web pages over the network on a AWS EC2 m5.large instance.
See [benchmark details](https://github.com/lightpanda-io/demo/blob/main/BENCHMARKS.md#crawler-benchmark)._

Lightpanda is the open-source browser made for headless usage:

- Javascript execution
- Support of Web APIs (partial, WIP)
- Compatible with Playwright[^1], Puppeteer, chromedp through [CDP](https://chromedevtools.github.io/devtools-protocol/)

Fast web automation for AI agents, LLM training, scraping and testing:

- Ultra-low memory footprint (16x less than Chrome)
- Exceptionally fast execution (9x faster than Chrome)
- Instant startup

[^1]: **Playwright support disclaimer:**
Due to the nature of Playwright, a script that works with the current version of the browser may not function correctly with a future version. Playwright uses an intermediate JavaScript layer that selects an execution strategy based on the browser's available features. If Lightpanda adds a new [Web API](https://developer.mozilla.org/en-US/docs/Web/API), Playwright may choose to execute different code for the same script. This new code path could attempt to use features that are not yet implemented. Lightpanda makes an effort to add compatibility tests, but we can't cover all scenarios. If you encounter an issue, please create a [GitHub issue](https://github.com/lightpanda-io/browser/issues) and include the last known working version of the script.

## Quick start

### Install
**Install from the nightly builds**

You can download the last binary from the [nightly
builds](https://github.com/lightpanda-io/browser/releases/tag/nightly) for
Linux x86_64 and MacOS aarch64.

*For Linux*
```console
curl -L -o lightpanda https://github.com/lightpanda-io/browser/releases/download/nightly/lightpanda-x86_64-linux && \
chmod a+x ./lightpanda
```

*For MacOS*
```console
curl -L -o lightpanda https://github.com/lightpanda-io/browser/releases/download/nightly/lightpanda-aarch64-macos && \
chmod a+x ./lightpanda
```

*For Windows + WSL2*

The Lightpanda browser is compatible to run on windows inside WSL. Follow the Linux instruction for installation from a WSL terminal.
It is recommended to install clients like Puppeteer on the Windows host.

**Install from Docker**

Lightpanda provides [official Docker
images](https://hub.docker.com/r/lightpanda/browser) for both Linux amd64 and
arm64 architectures.
The following command fetches the Docker image and starts a new container exposing Lightpanda's CDP server on port `9222`.
```console
docker run -d --name lightpanda -p 9222:9222 lightpanda/browser:nightly
```

### Dump a URL

```console
./lightpanda fetch --obey-robots --log-format pretty  --log-level info https://demo-browser.lightpanda.io/campfire-commerce/
```
```console
INFO  telemetry : telemetry status . . . . . . . . . . . . .  [+0ms]
      disabled = false

INFO  page : navigate . . . . . . . . . . . . . . . . . . . . [+6ms]
      url = https://demo-browser.lightpanda.io/campfire-commerce/
      method = GET
      reason = address_bar
      body = false
      req_id = 1

INFO  browser : executing script . . . . . . . . . . . . . .  [+118ms]
      src = https://demo-browser.lightpanda.io/campfire-commerce/script.js
      kind = javascript
      cacheable = true

INFO  http : request complete . . . . . . . . . . . . . . . . [+140ms]
      source = xhr
      url = https://demo-browser.lightpanda.io/campfire-commerce/json/product.json
      status = 200
      len = 4770

INFO  http : request complete . . . . . . . . . . . . . . . . [+141ms]
      source = fetch
      url = https://demo-browser.lightpanda.io/campfire-commerce/json/reviews.json
      status = 200
      len = 1615
<!DOCTYPE html>
```

### Start a CDP server

```console
./lightpanda serve --obey-robots --log-format pretty  --log-level info --host 127.0.0.1 --port 9222
```
```console
INFO  telemetry : telemetry status . . . . . . . . . . . . .  [+0ms]
      disabled = false

INFO  app : server running . . . . . . . . . . . . . . . . .  [+0ms]
      address = 127.0.0.1:9222
```

Once the CDP server started, you can run a Puppeteer script by configuring the
`browserWSEndpoint`.

```js
'use strict'

import puppeteer from 'puppeteer-core';

// use browserWSEndpoint to pass the Lightpanda's CDP server address.
const browser = await puppeteer.connect({
  browserWSEndpoint: "ws://127.0.0.1:9222",
});

// The rest of your script remains the same.
const context = await browser.createBrowserContext();
const page = await context.newPage();

// Dump all the links from the page.
await page.goto('https://demo-browser.lightpanda.io/amiibo/', {waitUntil: "networkidle0"});

const links = await page.evaluate(() => {
  return Array.from(document.querySelectorAll('a')).map(row => {
    return row.getAttribute('href');
  });
});

console.log(links);

await page.close();
await context.close();
await browser.disconnect();
```

### Telemetry
By default, Lightpanda collects and sends usage telemetry. This can be disabled by setting an environment variable `LIGHTPANDA_DISABLE_TELEMETRY=true`. You can read Lightpanda's privacy policy at: [https://lightpanda.io/privacy-policy](https://lightpanda.io/privacy-policy).

## Status

Lightpanda is in Beta and currently a work in progress. Stability and coverage are improving and many websites now work.
You may still encounter errors or crashes. Please open an issue with specifics if so.

Here are the key features we have implemented:

- [ ] CORS [#2015](https://github.com/lightpanda-io/browser/issues/2015)
- [x] HTTP loader ([Libcurl](https://curl.se/libcurl/))
- [x] HTML parser ([html5ever](https://github.com/servo/html5ever))
- [x] DOM tree
- [x] Javascript support ([v8](https://v8.dev/))
- [x] DOM APIs
- [x] Ajax
  - [x] XHR API
  - [x] Fetch API
- [x] DOM dump
- [x] CDP/websockets server
- [x] Click
- [x] Input form
- [x] Cookies
- [x] Custom HTTP headers
- [x] Proxy support
- [x] Network interception
- [x] Respect `robots.txt` with option `--obey-robots`

NOTE: There are hundreds of Web APIs. Developing a browser (even just for headless mode) is a huge task. Coverage will increase over time.

## Build from sources

### Prerequisites

Lightpanda is written with [Zig](https://ziglang.org/) `0.15.2`. You have to
install it with the right version in order to build the project.

Lightpanda also depends on
[v8](https://chromium.googlesource.com/v8/v8.git),
[Libcurl](https://curl.se/libcurl/) and [html5ever](https://github.com/servo/html5ever).

To be able to build the v8 engine, you have to install some libs:

For **Debian/Ubuntu based Linux**:

```
sudo apt install xz-utils ca-certificates \
    pkg-config libglib2.0-dev \
    clang make curl git
```
You also need to [install Rust](https://rust-lang.org/tools/install/).

For systems with [**Nix**](https://nixos.org/download/), you can use the devShell:
```
nix develop
```

For **MacOS**, you need cmake and [Rust](https://rust-lang.org/tools/install/).
```
brew install cmake
```

### Build and run

You an build the entire browser with `make build` or `make build-dev` for debug
env.

But you can directly use the zig command: `zig build run`.

#### Embed v8 snapshot

Lighpanda uses v8 snapshot. By default, it is created on startup but you can
embed it by using the following commands:

Generate the snapshot.
```
zig build snapshot_creator -- src/snapshot.bin
```

Build using the snapshot binary.
```
zig build -Dsnapshot_path=../../snapshot.bin
```

See [#1279](https://github.com/lightpanda-io/browser/pull/1279) for more details.

## Test

### Unit Tests

You can test Lightpanda by running `make test`.

### End to end tests

To run end to end tests, you need to clone the [demo
repository](https://github.com/lightpanda-io/demo) into `../demo` dir.

You have to install the [demo's node
requirements](https://github.com/lightpanda-io/demo?tab=readme-ov-file#dependencies-1)

You also need to install [Go](https://go.dev) > v1.24.

```
make end2end
```

### Web Platform Tests

Lightpanda is tested against the standardized [Web Platform
Tests](https://web-platform-tests.org/).

We use [a fork](https://github.com/lightpanda-io/wpt/tree/fork) including a custom
[`testharnessreport.js`](https://github.com/lightpanda-io/wpt/commit/01a3115c076a3ad0c84849dbbf77a6e3d199c56f).

For reference, you can easily execute a WPT test case with your browser via
[wpt.live](https://wpt.live).

#### Configure WPT HTTP server

To run the test, you must clone the repository, configure the custom hosts and generate the
`MANIFEST.json` file.

Clone the repository with the `fork` branch.
```
git clone -b fork --depth=1 git@github.com:lightpanda-io/wpt.git
```

Enter into the `wpt/` dir.

Install custom domains in your `/etc/hosts`
```
./wpt make-hosts-file | sudo tee -a /etc/hosts
```

Generate `MANIFEST.json`
```
./wpt manifest
```
Use the [WPT's setup
guide](https://web-platform-tests.org/running-tests/from-local-system.html) for
details.

#### Run WPT test suite

An external [Go](https://go.dev) runner is provided by
[github.com/lightpanda-io/demo/](https://github.com/lightpanda-io/demo/)
repository, located into `wptrunner/` dir.
You need to clone the project first.

First start the WPT's HTTP server from your `wpt/` clone dir.
```
./wpt serve
```

Run a Lightpanda browser

```
zig build run -- --insecure-disable-tls-host-verification
```

Then you can start the wptrunner from the Demo's clone dir:
```
cd wptrunner && go run .
```

Or one specific test:

```
cd wptrunner && go run . Node-childNodes.html
```

`wptrunner` command accepts `--summary` and `--json` options modifying output.
Also `--concurrency` define the concurrency limit.

:warning: Running the whole test suite will take a long time. In this case,
it's useful to build in `releaseFast` mode to make tests faster.

```
zig build -Doptimize=ReleaseFast run
```

## Contributing

Lightpanda accepts pull requests through GitHub.

You have to sign our [CLA](CLA.md) during the pull request process otherwise
we're not able to accept your contributions.

## Why?

### Javascript execution is mandatory for the modern web

In the good old days, scraping a webpage was as easy as making an HTTP request, cURL-like. It’s not possible anymore, because Javascript is everywhere, like it or not:

- Ajax, Single Page App, infinite loading, “click to display”, instant search, etc.
- JS web frameworks: React, Vue, Angular & others

### Chrome is not the right tool

If we need Javascript, why not use a real web browser? Take a huge desktop application, hack it, and run it on the server. Hundreds or thousands of instances of Chrome if you use it at scale. Are you sure it’s such a good idea?

- Heavy on RAM and CPU, expensive to run
- Hard to package, deploy and maintain at scale
- Bloated, lots of features are not useful in headless usage

### Lightpanda is built for performance

If we want both Javascript and performance in a true headless browser, we need to start from scratch. Not another iteration of Chromium, really from a blank page. Crazy right? But that’s what we did:

- Not based on Chromium, Blink or WebKit
- Low-level system programming language (Zig) with optimisations in mind
- Opinionated: without graphical rendering
