Technology Radar
Axe-core is an open-source accessibility testing tool that detects issues in websites and other HTML-based applications. It checks pages for compliance with standards such as WCAG — including conformance levels A, AA and AAA — and flags common accessibility best practices. Since first appearing in the Radar in Trial in 2021, several of our teams have adopted Axe-core with clients. Accessibility is increasingly a mandatory quality attribute. In Europe, for example, regulations such as the European Accessibility Act require organizations to ensure their digital services meet accessibility requirements. Axe-core fits well within modern development workflows by enabling automated checks in CI pipelines. This helps teams prevent regressions, maintain compliance and receive early feedback during development, ensuring accessibility is part of the feedback loop, particularly as AI-assisted and agentic coding tools are more widely adopted.
Making the web inclusive requires serious attention to ensure accessibility is considered and validated at all stages of software delivery. Many of the popular accessibility testing tools are designed for testing after a web application is complete; as a result, issues are detected late and often are harder to fix, accumulating as debt. In our recent internal work on ThoughtWorks websites, we included the open-source accessibility (a11y) testing engine axe-core as part of our build processes. It provided team members with early feedback on adherence to accessibility rules, even during early increments. Not every issue can be found through automated inspection, though. Extending the functionality of axe-core is the commercially available axe DevTools, including functionality that guides team members through exploratory testing for a majority of accessibility issues.
