Zuul

Zuul was the easiest way to run JavaScript test suites in real browsers. You wrote tests with your favorite framework, ran `zuul` locally, and CI pushed them to Sauce Labs. Cory House (defunctzombie) built it when "headless browser testing" was a moving target. It worked with Mocha, QUnit, Jasmine, and Tape; supported jQuery, React, and Angular test setups; and required almost no config. The repo was archived in 2021 after Cory moved to .NET. The closest modern replacement is Karma + headless Chrome, but Zuul's "just works" setup was a level above. The npm package still installs and runs on modern Node, but the Sauce Labs free tier ended years ago.