rustwright 0.1.1

A Rust-backed, CDP-first Python automation library with a Playwright-compatible sync API

A Rust rewrite of Playwright, a popular browser automation library. Rustwright is interoperable with Playwright but runs on an in-process Rust CDP engine — 2.55× faster and 70% less memory (no Node driver), with no Playwright automation fingerprint. Alpha; Chromium-only.

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What is Rustwright?

Rustwright is a browser automation library for Python and Node.js that keeps the Playwright API you already know but drives Chromium from a native Rust engine speaking raw Chrome DevTools Protocol — no driver subprocess in the path.

playwright-python:  your code ──pipe──► Node driver ──CDP──► Chromium
rustwright:         your code ────────── raw CDP ──────────► Chromium

Quickstart

Rustwright is interoperable with Playwright — install it, change one import, and your existing code runs on the Rust engine.

Python

pip install rustwright
python -m rustwright install chromium

- from playwright.sync_api import sync_playwright
+ from rustwright.sync_api import sync_playwright

  with sync_playwright() as p:
      browser = p.chromium.launch(headless=True)
      page = browser.new_page()
      page.goto("https://example.com")
      print(page.title())
      browser.close()

Node.js (experimental)

Install from npm:

npm install rustwright

The Node binding drives an existing Chromium/Chrome — point Rustwright at it with RUSTWRIGHT_CHROMIUM, CHROME, or CHROMIUM. Prefer to build from source? git clone the repo and run npm install && npm run build in node/.

- import { chromium } from 'playwright';
+ import { chromium } from 'rustwright';

  const browser = await chromium.launch();
  const page = await browser.newPage();
  await page.goto('https://example.com');
  console.log(await page.title());
  await browser.close();

Only a subset of the API surface is bridged — see Limitations.

Why Rustwright?

• No Node driver subprocess. playwright-python launches and pipes to a bundled Node driver. Rustwright's engine is native — the browser-control code runs in-process.
• Raw CDP, in Rust. A from-scratch async CDP client — not a wrapper around another automation library.
• No Playwright automation fingerprint. The driver never loads, so its signatures never appear. See Automation detection.
• Trusted input by default. Clicks and typing go through real CDP input events (Input.dispatchMouseEvent), not synthetic element.click() DOM calls. Untrusted DOM shortcuts are opt-in only.
• Cross-origin iframes (OOPIF). Auto-attaches out-of-process iframe targets with flattened CDP sessions and routes frame_locator() across origins.
• One engine, two languages. The same Rust core backs the Python and Node bindings.

How it works

One Rust core — an async CDP client built on Tokio (WebSocket, with opt-in Unix-pipe transport) — talks to Chromium directly, and thin PyO3 (Python) and napi-rs (Node) bindings expose it in-process. The two-line diagram above is the entire architecture.

Already have a Chromium/Chrome binary? Point Rustwright at it with RUSTWRIGHT_CHROMIUM, CHROME, or CHROMIUM.

Remote browsers (Skyvern)

Rustwright drives browsers — but you still need somewhere to run them. Skyvern (the team behind Rustwright) offers hosted Browser Sessions as a paid service that funds this project.

Features:

• Persistent cloud browsers — logins, cookies, and tab state carry across runs
• Configurable timeouts — 5 minutes to 24 hours (60 min default)
• Proxies in 21 countries
• Live view — watch and interact with the session in the Skyvern Cloud UI

Each session returns a browser_address CDP endpoint that Rustwright connects to like any remote Chromium (sessions bill while open).

Get started:

1. Make an account at app.skyvern.com
2. Grab your API key from Settings
3. pip install skyvern

import asyncio
from rustwright.async_api import async_playwright
from skyvern import Skyvern

async def main():
    session = await Skyvern(api_key="<SKYVERN_API_KEY>").create_browser_session()

    async with async_playwright() as p:
        browser = await p.chromium.connect_over_cdp(session.browser_address)
        page = await browser.new_page()
        await page.goto("https://example.com")

asyncio.run(main())

Remote sessions are Python-only for now — Rustwright's Node binding doesn't support connect_over_cdp yet (it's on the Roadmap).

Automation detection

Because Rustwright never loads Playwright's Node driver, it never emits the automation signatures that ship with it:

• No Playwright driver signatures — no __playwright__binding__ / utility-world globals, no driver bootstrap. The backend reports playwright_driver: "none".
• No Runtime.enable on the default path — a normal launch + navigate never enables the CDP Runtime domain, closing the Runtime.enable console-serialization leak behind isAutomatedWithCDP. (Console/page-error/binding opt-ins still enable it lazily — detectable by design.)
• Headless identity normalized by default — launches with --disable-blink-features=AutomationControlled, rewrites HeadlessChrome/ → Chrome/ in the UA and client hints, and installs a navigator.webdriver cleanup init script.

Local fingerprint runs — default Playwright failed webdriver/headless checks that Rustwright passed; these are local diagnostics, not a guarantee:

Probe	Result
SannySoft	✅ Clean
BrowserScan	✅ Clean
DeviceAndBrowserInfo	✅ Clean (after the Runtime-domain cleanup)
CreepJS	⚠️ Detects headless

[!IMPORTANT] Rustwright is not "undetectable." It is not a CAPTCHA or Cloudflare bypass, and it is not fully CDP-invisible — it still uses CDP primitives (Target.setAutoAttach, init scripts, and lazy Runtime.enable for console event/pageerror event/binding opt-ins). The claim is narrow: no Playwright-specific automation fingerprint, plus baseline signal hygiene.

Benchmarks

The headline numbers are local diagnostics, not yet capped-CI evidence. On speed, one dev-host run (warm browser, 5 iterations) won 16 of 17 case means:

Run	Cases	Rustwright	playwright-python	Speedup
Local dev host (warm browser, 5 iterations)	17	5,256 ms	13,418 ms	2.55×

Treat it as a diagnostic, not a launch claim — it is not capped-Docker/CI evidence. Methodology: BENCHMARK.md.

On memory, a form-fill diagnostic recorded the client library's footprint at 133.5 MiB for playwright-python (Python + Node driver) versus 40.6 MiB for Rustwright (no driver) — about 70% less; a separate async-concurrency diagnostic measured ~66% less on the same client-stack basis. Both cover the part the library controls — Chromium-dominated whole-process memory is roughly equal — and both are demo-grade diagnostics, not capped-CI evidence.

Alternatives

	Rustwright	playwright-python	Puppeteer	Patchright
API	Playwright-shaped (Py + Node)	Official Python Playwright	JS/TS Puppeteer	Playwright drop-in fork
Engine / transport	Rust core, raw CDP	Python → Node driver	Node over CDP	Patched PW driver
In-process engine (no driver subprocess)	✅	❌ bundled Node driver	✅ Node is the runtime	❌ Playwright-style driver
Browsers	Chromium only	Chromium, Firefox, WebKit	Chrome, Firefox	Chromium-based
Default input	Trusted CDP events	Browser-level	Browser / CDP	Playwright + stealth
Cross-origin iframes	OOPIF (alpha)	Mature	Frame APIs	Inherits Playwright
Playwright fingerprint	No	Yes	n/a	Patched
Maturity	🟠 Alpha	🟢 Mature	🟢 Mature	🟡 Focused fork

Rustwright's lane: a Rust CDP engine under the Playwright API, for Chromium.

Limitations

See LIMITATIONS.md for detail.

• Alpha — API shape covered; full behavioral parity not yet proven.
• API coverage — ~96% of Playwright's Python sync API (515 of 536 methods; 411 exercised by the shared parity registry); the async API provides 488 of 536. Full report: docs/PARITY.md.
• Chromium only — Firefox and WebKit error explicitly.
• Node bindings are early — a subset of the surface is bridged (launch, newPage, goto, click, fill, title, textContent, evaluate, screenshot, close); contexts, routing, tracing, and locators are Python-only for now.
• Async concurrency (Python) — the async API wraps the sync engine via threads; recommended for ≈≤25 concurrent workflows/process, not high fan-out.
• OOPIF — residual gaps in non-main-frame JSHandle follow-ups and drag/screenshot/bounding-box.
• Automation detection is partial — 3 of 4 public fingerprint targets clean in local runs (CreepJS still detects headless). No undetectability promise.

Roadmap

• Language bindings — one Rust engine, many languages: Go, Java, Kotlin, C#/.NET, Ruby, and PHP (plus a native Rust API)
• Rustwright MCP server — expose browser automation as tools for MCP-compatible AI agents
• CI / Testbox-backed benchmark evidence
• Broaden the Node.js surface (contexts, routing, locators)
• Close remaining OOPIF gaps

Recently shipped:

• Python package published to PyPI
• Node.js binding published to npm
• Native async engine over the Tokio CDP core
• OOPIF auto-attach with flattened CDP sessions
• 515/515 shared parity suite green against real Playwright
• Runtime.enable console-serialization leak closed on the default path

Firefox and WebKit are not planned — Rustwright is deliberately Chromium-only.

Contributing

Rustwright is Rust + Python + Node. cargo builds the engine; maturin develop --release installs the Python package; cd node && npm run build builds the Node addon; the Python suite exercises the engine against real Chromium. Full Docker gate: 1,046 tests pass (6 skipped), plus 515/515 shared parity cases run against real Playwright; CI (test.yml) runs a fast representative subset on every PR.

See CONTRIBUTING.md for build details and the code-layout reality.

Project status

Rustwright is an early alpha from Skyvern, developed in the open. If the architecture resonates, give it a ⭐.

Questions, ideas, or want to help? Join the Skyvern community on Discord.

License

MIT © 2026 Ikonomos Inc (dba Skyvern)

_{Built with 🦀🐉 and a lot of CDP frames · Skyvern-AI/rustwright}