Alternative Browser Engines

Playwright and Puppeteer drive full Chromium — the most accurate way to test what users see. But a new class of lightweight, agent-era browsers has appeared, and CodeceptJS can drive them through dedicated helpers:

Obscura — an open-source Rust browser with a real V8 engine. From v0.2.0, the default release build also renders — real layout, computed styles, and screenshots — with -no-render builds still available for pure-speed, nothing-painted scraping mode. Release archives are available for Linux, macOS, and Windows.
Kitesurf — Cloudflare’s browser that runs in V8 isolates on Cloudflare Workers, with a real layout and rendering pipeline. Cloud-only, free in beta, planned to be open-sourced.

Both speak Chrome DevTools Protocol. CodeceptJS drives them with raw CDP — one round-trip per action, no stale element handles — which is why suites on these browsers run fast and never hang on navigation races.

When are they better than Playwright?

Smoke suites where startup and execution time matter. Obscura is distributed as a standalone binary and is designed for lightweight browser automation. Benchmark it against your own pages and CI environment before choosing it for a PR gate.

Massive parallel scale. Kitesurf sessions are Cloudflare Workers — they spawn in about a second, cost nothing while idle, and there is no practical ceiling on how many you run at once. Combined with run-workers, every worker acquires its own cloud browser:

// codecept.conf.js — each worker independently loads the config,
// so each one gets its own Kitesurf session automatically
export const config = {
  helpers: {
    Kitesurf: {
      url: 'https://staging.myapp.com',
    },
  },
}

npx codeceptjs run-workers 16

Sixteen cloud browsers, zero local resources, feedback in the time of your slowest test. Scale the number up as far as your suite can split — the browsers are no longer the bottleneck, and your CI runner only coordinates.

Testing the DOM, not the pixels. Most functional assertions — text appears, form submits, redirect happens, cookie is set — do not need a GPU raster pipeline. Obscura executes your app’s real JavaScript in real V8; it only skips painting. For API-adjacent flows (login → dashboard data appears), that is exactly the right amount of browser.

Constrained environments. ARM CI runners, thin containers, air-gapped machines: a static binary with no system dependencies goes where Chromium will not.

Optional stealth builds. Obscura publishes separate -stealth archives. Treat their behaviour as an Obscura capability rather than a browser-compatibility guarantee from CodeceptJS.

When to stay with Playwright

Anything visual: visual regression, PDF (neither helper exposes PDF output). Obscura’s v0.2.0+ rendering/CSS engine is new and independently implemented — expect edge cases and gaps versus a real browser, especially around inherited properties and less common computed-style values.
Visibility semantics on -no-render Obscura builds (and v0.1.x): every element reports as visible — seeElement/dontSeeElement throw and point you to seeElementInDOM. On v0.2.0+ default builds, CDPBrowser detects the real layout engine per binary and visibility works normally.
Complex input: drag-and-drop, hover chains, file uploads, iframes, multi-tab, service workers.
Cross-browser coverage (Firefox, WebKit).
Testing local apps with Kitesurf: the cloud browser must reach your app; use a tunnel (cloudflared tunnel --url http://localhost:3000) or a deployed environment.

Configuration

CodeceptJS 4.2 is tested in CI with Obscura 0.2.2. Obscura 0.2.x is recommended; 0.1.x and -no-render builds operate without layout, visibility assertions, or screenshots. See Installation for platform-specific archive names.

helpers: {
  Obscura: {
    url: 'http://localhost:3000',
  },
}

helpers: {
  Kitesurf: {
    url: 'https://staging.myapp.com',
    accountId: process.env.CF_ACCOUNT_ID,
    apiToken: process.env.CF_API_TOKEN,
  },
}

Obscura’s three connection modes

Obscura manages its own obscura serve process, the same way Playwright manages its own browser process — there is nothing to start by hand in the common case:

Self-launch (default) — leave endpoint unset. The helper resolves a binary (binaryPath in the config, then OBSCURA_PATH, then obscura on PATH), spawns obscura serve on a free port, and kills it when the run ends. Not setting port is intentional: a free port is picked automatically, which is what makes run-workers collision-free — every worker gets its own instance without any config.
```
helpers: {
  Obscura: {
    url: 'http://localhost:3000',
    binaryPath: '/usr/local/bin/obscura', // optional override, like Playwright's executablePath
  },
}
```
Attach — set endpoint explicitly to connect to an Obscura instance you manage yourself (already running locally, in a container, or on a remote host). The helper only connects; it never spawns or kills anything.
```
helpers: {
  Obscura: {
    url: 'http://localhost:3000',
    endpoint: 'http://127.0.0.1:9222',
  },
}
```
Courtesy-attach — only relevant when endpoint is unset and no binary can be resolved either. If something is already answering on the conventional http://127.0.0.1:9222, the helper attaches to it (and, again, never kills it) instead of failing outright. This exists so that “start Obscura by hand and just run the tests” keeps working without any config, while self-launch is still the default for everyone else.

Capability matrix

	Playwright	Obscura	Kitesurf
Real JS execution (V8)	yes	yes	yes
Layout / getBoundingClientRect	yes	yes (v0.2.0+ default builds); synthetic on `-no-render`/v0.1.x	yes
Screenshots	yes	yes (v0.2.0+ default builds); no on `-no-render`/v0.1.x	yes
Visibility assertions	yes	yes (v0.2.0+ default builds); no, DOM-presence only, on `-no-render`/v0.1.x	yes
Screencast / video (`screencast` plugin)	yes — WebM via `page.screencast`, with caption burn-in	yes — APNG via CDP `Page.startScreencast`, assembled in-process (v0.2.0+ default builds; verified PNG frames on the live server); no caption burn-in	untested
Startup model	local browser process	standalone local binary	remote cloud session
Parallel scale	machine-bound	machine-bound (light)	near-unlimited (cloud)
Where it runs	local/grid	local	Cloudflare only
License / cost	open source	Apache-2.0	proprietary, free beta

See helper reference pages: Obscura, Kitesurf.