Alternative Browser Engines

Playwright drives full Chromium, Firefox and WebKit: the most accurate way to test what users see, at the cost of a heavy browser per worker. Alternative engines trade part of that accuracy for speed, a small footprint, or cloud scale. They are a good fit for functional tests (text appears, form submits, redirect happens, cookie is set) and a poor one for anything visual.

Your tests do not change. I.amOnPage, I.click, I.fillField, I.see, I.seeElement and the rest of the I.* web API work the same; you only swap the helper in the config. All engines below speak Chrome DevTools Protocol, so there is no npx playwright install step.

Compared to Playwright, none of them supports iframes (switchTo), multiple tabs, popups, dragAndDrop, moveCursorTo, or Playwright-only APIs such as usePlaywrightTo and mockRoute. Tag scenarios that need those and skip them on the alternative engine:

npx codeceptjs run --grep @playwright-only --invert

To see which I.* actions the configured engine supports:

npx codeceptjs list

Obscura

Obscura is a lightweight open-source browser with a real V8 engine and its own rendering engine, distributed as a single binary for Linux, macOS and Windows. Unlike Lightpanda it renders: layout, visibility checks, screenshots and the screencast plugin work.

Limitations:

attachFile does not upload files.
Clicks inside nested shadow DOM do not work.
focus and blur have no effect.
Clipboard actions do not work.
A <select multiple> submits only its first selected option.
An element inside a visibility: hidden parent is reported as visible.
Some computed styles (cursor, user-select) differ from Chromium.
Rich text editors TinyMCE, Trix, Monaco and ProseMirror do not work.

Setup

Install Obscura following the official instructions and put obscura on PATH. Then enable the helper:

export const config = {
  helpers: {
    Obscura: {
      url: 'http://localhost:3000',
    },
  },
}

If the binary is not on PATH, set binaryPath in the config or the OBSCURA_PATH environment variable.

Usage

npx codeceptjs run

The helper starts obscura serve on a free port before the first test and stops it after the last one, like Playwright manages Chromium. Each worker gets its own instance:

npx codeceptjs run-workers 8

To connect to an Obscura you started yourself, set endpoint; the helper then never starts or stops it:

obscura serve --port 9222 --allow-private-network --allow-file-access

Obscura: {
  url: 'http://localhost:3000',
  endpoint: 'http://127.0.0.1:9222',
}

All options: Obscura helper reference.

Lightpanda

Lightpanda is an open-source headless browser built from scratch for automation. It runs your app’s JavaScript in V8 but never paints anything, which makes it start in milliseconds and use a fraction of Chromium’s memory. It computes enough layout for seeElement, waitForVisible and other visibility checks.

Limitations:

No screenshots: saveScreenshot, failure screenshots and the screencast plugin do not work.
No scrolling: scrollTo and scrollPageToBottom have no effect.
clickXY does not work.
Clipboard actions do not work.
Computed styles cover display, visibility and opacity; other CSS properties are unreliable.
Rich text editors TinyMCE, Trix and Monaco do not work.
Linux and macOS only; on Windows use WSL2.
Licensed under AGPL-3.0. It runs as a separate process, so it does not affect the license of your tests.

Setup

Install Lightpanda following the official instructions and put lightpanda on PATH. Then enable the helper:

export const config = {
  helpers: {
    Lightpanda: {
      url: 'http://localhost:3000',
    },
  },
}

If the binary is not on PATH, set binaryPath in the config or the LIGHTPANDA_PATH environment variable.

Usage

npx codeceptjs run

The helper starts lightpanda serve on a free port with telemetry turned off, and stops it after the last test. Each worker gets its own instance:

npx codeceptjs run-workers 8

To connect to a Lightpanda you started yourself, set endpoint; the helper then never starts or stops it:

LIGHTPANDA_DISABLE_TELEMETRY=true lightpanda serve --host 127.0.0.1 --port 9222

Lightpanda: {
  url: 'http://localhost:3000',
  endpoint: 'http://127.0.0.1:9222',
}

All options: Lightpanda helper reference.

Moli

Moli is an open-source headless browser built in Rust for automation. It runs your app’s JavaScript in V8 and computes real CSS, but skips layout and painting, so it starts fast and stays small. Visibility checks such as seeElement and waitForVisible work.

Limitations:

No screenshots: saveScreenshot, failure screenshots and the screencast plugin do not work.
clickXY does not work.
attachFile uploads files without a MIME type; the server receives application/octet-stream.
Links have no default color: a computes color: rgb(0, 0, 0).

Setup

Install Moli following the official instructions and put moli on PATH. Then enable the helper:

export const config = {
  helpers: {
    Moli: {
      url: 'http://localhost:3000',
    },
  },
}

If the binary is not on PATH, set binaryPath in the config or the MOLI_PATH environment variable.

Usage

npx codeceptjs run

The helper starts moli serve on a free port before the first test and stops it after the last one. Each worker gets its own instance:

npx codeceptjs run-workers 8

To connect to a Moli you started yourself, set endpoint; the helper then never starts or stops it:

moli serve --host 127.0.0.1 --port 9222

Moli: {
  url: 'http://localhost:3000',
  endpoint: 'http://127.0.0.1:9222',
}

All options: Moli helper reference.

Kitesurf

Kitesurf is Cloudflare’s browser running on Cloudflare Workers, with a real layout and rendering pipeline. Sessions start in about a second and nothing runs on your machine, so the number of parallel browsers is limited only by how far your suite splits.

Limitations:

Cloud only, currently a free beta.
The browser cannot reach localhost: test a deployed environment or expose your app with a tunnel such as cloudflared tunnel --url http://localhost:3000.

Setup

Enable Cloudflare Browser Run and create an API token with the Browser Rendering → Edit permission. Export the credentials:

export CF_ACCOUNT_ID=your-account-id
export CF_API_TOKEN=your-api-token

Then enable the helper:

export const config = {
  helpers: {
    Kitesurf: {
      url: 'https://staging.myapp.com',
    },
  },
}

Usage

Every worker opens its own cloud session:

npx codeceptjs run-workers 16

All options: Kitesurf helper reference.