Catch visual regressions with cross-browser screenshots

Generates SmartUI visual regression test configurations for screenshot comparison on TestMu AI cloud, framework-agnostic across Playwright, Selenium, Cypress, and Puppeteer. With Playwright, the @lambdatest/smartui-cli SDK's smartuiSnapshot(page, name) call captures a named screenshot at any point in the test flow; with Selenium, the equivalent is a smartui.takeScreenshot=<name> call via JavascriptExecutor. Execution runs through the SmartUI CLI: install @lambdatest/smartui-cli, generate smartui.config.json via npx smartui config:create, then wrap the actual test command with npx smartui exec -- <test command> (works with a plain Node script or npx playwright test). The config file sets which browsers to capture (chrome/firefox/safari), which viewports (e.g. 1920x1080 desktop, 1366x768 laptop, 375x812 mobile), and render-wait timing (waitForPageRender, waitForTimeout) so screenshots aren't taken mid-render. Storybook component libraries get their own command: npx smartui storybook <url> --config smartui.config.json captures every story as a snapshot. The approval workflow is fixed: the first run creates baseline screenshots, every subsequent run compares against that baseline, differences are highlighted in the SmartUI dashboard, a human approves or rejects each diff there, and approved screenshots become the new baseline. Four anti-patterns are called out: no viewport config misses responsive-layout issues (fix: configure multiple viewports); no render wait produces incomplete screenshots (fix: set waitForPageRender); screenshotting everything creates review noise (fix: capture only key pages/components); and skipping the dashboard approval step misses real regressions (fix: always review diffs before approving). Cloud authentication uses different environment variables depending on approach: the CLI path (npx smartui exec) reads PROJECT_TOKEN from the SmartUI dashboard, while the Selenium cloud-grid path reads LT_USERNAME/LT_ACCESS_KEY and passes them plus a smartUI.project name inside the LT:Options capabilities object when connecting to the LambdaTest remote hub.

const { chromium } = require('playwright');
const { smartuiSnapshot } = require('@lambdatest/smartui-cli');

(async () => {
  const browser = await chromium.launch();
  const page = await browser.newPage();
  await page.goto('https://example.com');
  await smartuiSnapshot(page, 'Homepage');
  await browser.close();
})();

Use it whenever a user mentions SmartUI, visual regression, screenshot comparison, or visual testing, regardless of which browser automation framework (Playwright, Selenium, Cypress, Puppeteer) they're already using.

Input is a set of pages or components to snapshot, plus target browsers and viewports. Output is a smartui.config.json and framework-specific snapshot calls that, once run, produce baseline or comparison screenshots reviewable in the SmartUI dashboard.

Integrates with Playwright, Selenium, Cypress, and Puppeteer via the @lambdatest/smartui-cli SDK or CLI wrapper, with Storybook for component-level snapshots, and with TestMu AI's LambdaTest cloud grid for cross-browser capture using LT_USERNAME/LT_ACCESS_KEY credentials.

QA engineers and developers setting up visual regression testing who want framework-agnostic screenshot comparison with a dashboard-based approval workflow, regardless of which browser automation tool their existing tests already use.