Build and Deploy Flawless Frontends with Automated Visual Testing

Manual testing, whether conducted internally or outsourced, poses challenges due to potential human errors.

Testers may overlook issues or misinterpret visual cues, leading to inaccurate results, and impacting overall test coverage and product reliability.

It can also be time-consuming, especially for complex apps or websites, requiring manual checks for each page or screen.

Another drawback is the inconsistency in evaluation, with different testers, yielding varying results.

RCA (root cause analysis) also takes a hit, delaying the testing process and resolution of critical defects.

Lastly, the cost of manual Visual Testing can be substantial, particularly with a large number of testers required for comprehensive testing.

Functional testing, though incredibly important, is simply not designed to test applications from a visual standpoint. Instead of looking at the visuals, they only test the abstractions underneath. Trying to bolt on assertions of visual aspects doesn’t work and creates fragile and unmaintainable test suites.

Automated Visual Testing is similar to functional testing in that it’s designed to be an automated process that runs alongside code reviews. Unlike functional testing, however, visual tests don’t pass or fail. Automated Visual Testing simply detects visual changes and provides a review process to determine whether or not the changes are correct.

Open-source libraries have cropped up over the years, providing simple snapshotting and image diffing capabilities, but lack the infrastructure and workflow necessary to enable continuous visual coverage.

They can be difficult to integrate with your existing testing infrastructure, so automating the process of Visual Testing can be challenging. You end up doing manual testing, which can be time-consuming and error-prone.

Open-source libraries are often unmaintained. They may not be updated with new features or bug fixes quickly.

They are also often narrow, supporting a limited number of browsers, devices, or screen resolutions.

The most pressing challenges that keep frontend engineers on their toes

In a Visual Testing survey conducted, we asked frontend engineers what are their most difficult challenges at work. These were the responses:

• Maintaining Cross-browser compatibility: 38% of surveyed want to ensure websites or apps work smoothly across multiple browsers.
• Manual UI consistency checks: 30% of respondents said maintaining a consistent user interface across different screens, resolutions, and devices is a challenge.
• Writing and managing tests: 16% voted that designing comprehensive test suites, crafting solid test cases, and keeping track of test coverage is a challenge.
• Refactoring challenges and fear of breaking: 16% want to find safe and effective ways to refactor code, ensuring that existing functionality remains intact while bringing in much-needed improvements.

Automated Visual Testing provides continuous visual feedback regardless of the context of the change or the “correctness” of the change. In situations where your UI shouldn’t change (like deleting CSS, refactoring CSS, or upgrading dependencies), Automated Visual Testing gives you confidence that your entire UI has remained stable. That built-in coverage not only extends to the breadth of your UI—from your most critical flows down to your 404 page—but also to the combinations of those pages across browsers and screen sizes.

Visual regression tests are vital for preventing visual bugs from slipping into production and disrupting user experiences. While functional and manual testing catch bugs, they often don’t discover bugs, especially visual discrepancies.

Let’s go back to our survey. We asked people how often they perform regression testing on their native apps and websites

A striking trend that emerges from the survey is the substantial percentage of respondents who engage in regression testing less frequently—30% for native apps and 27% for websites. This is concerning, as it highlights a potential blind spot in the QA process.

When questioned on the number of visual regression tests run, 32% admitted to not running any visual regression tests at all, which can potentially result in a deterioration of user experience and functionality over time.

Automated Visual Testing fills the gap by providing a systematic approach for consistent and frequent regression testing. By comparing screenshots across different devices and resolutions, QA teams can meticulously compare UI elements and screens against established baselines, detecting even the slightest deviations that could indicate bugs or unintended changes.

Automated Visual Testing scales with a level of precision not feasible with the human eye, at a faster rate than the brain can work, and at a fraction of the cost. It has virtually no limitations to scale and has a low incremental cost that doesn’t increase exponentially with complexity.

The time-saving and confidence-boosting benefits of Automated Visual Testing also extend to teammates other than developers. For designers verifying the implementation of designs, product managers staying in the loop, or product marketers grabbing updated UI screenshots, Automated Visual Testing provides immense value to cross-functional product teams.

When making code changes, it’s often a fear of the unknown that causes the most stress—whether it’s fear of breaking something or uncertainty about the full scope of design implementation. That risk, and the inability to mitigate it, is why teams spend time and resources manually looking for visual bugs. It’s also why teams end up trying to write functional tests to prevent visual regressions.

Visual Testing automates that work, empowering you to merge and deploy with full confidence that your app will look exactly as it should across browsers and screen sizes.