Ace, an accessibility checker for EPUB!
A DAISY Consortium project.
Latest version: v1.0.0-RC.1 (release candidate)
Under the hood, most of the HTML checks are powered by aXe, an engine for automated testing of HTML from Deque Systems.
During the evaluation of an EPUB, Ace loads each HTML content document in a headless browser, using headless Chrome via Puppeteer.