Retail • Media • SaaS
Visual and UI Regression Monitoring
Detect unexpected UI and layout changes before customers notice broken experiences.
Challenge
Functional tests pass while important visual regressions still reach production. A CSS change that shifts a button off-screen, a font that fails to load, or a layout that breaks at a specific viewport width — none of these trigger functional test failures because the DOM structure is unchanged. Teams that rely on pixel-perfect screenshot comparison deal with constant false positives from antialiasing, dynamic content, and rendering differences.
Stably approach
Stably layers AI-powered visual checks on critical pages and flows. Instead of pixel-by-pixel comparison, AI assertions evaluate whether the page looks correct based on natural language descriptions — "the navigation bar is visible and properly aligned" or "the hero section contains the expected headline and CTA button." This filters out noise from dynamic content and minor rendering differences while catching meaningful layout regressions. Visual checks run alongside functional tests in CI for a complete quality signal.
What changes
Describe what "correct" looks like in plain English
Instead of comparing screenshots pixel-by-pixel, write assertions like toMatchScreenshotPrompt("the pricing table has three columns with the Pro plan highlighted"). The AI evaluates the rendered page visually — it passes when the layout is right, even if the exact prices or copy changed.
Dynamic content stops breaking your visual tests
Timestamps, user avatars, and personalized content change every run. Pixel-diff tools flag these as failures. Stably's AI assertions focus on layout and structure — "the dashboard has a sidebar, main content area, and header" — so dynamic data does not trigger false positives.
A CSS regression is caught before it ships, not by a customer screenshot
A developer changes a utility class and accidentally hides the checkout button on mobile. Functional tests pass because the button exists in the DOM. Stably's visual assertion — "the Buy Now button is visible below the product image" — fails and blocks the deploy.
Visual checks run alongside functional tests in CI
Add toMatchScreenshotPrompt assertions to existing Playwright tests. They execute as part of your normal test suite — no separate visual testing tool, no separate CI job, no separate dashboard to check.
When this is the right fit
- Design regressions are found late by support or customers
- UI checks are manual and inconsistent across teams
- Frequent frontend releases increase regression risk
- Pixel-based visual tests produce too many false positives to be useful