These organizations and open-source projects, and many others, use QUnit to keep their code in check.
ember-table
Discourse, discourse-subscriptions
Underscore.js, Backbone.js
formcore, layersnap, tablesaw
Vault, Consul, Nomad
KAS, structured.js
kiwix-js
OpenUI5, ui5-tooling
ember-computable, eslint-plugin-square, qunit-bdd
Hogan.js, twitter-text
MediaWiki, VisualEditor, CSSJanus
WordPress
Benchmark.js, Platform.js
Bootstrap, bootlint
CefSharp
core-js
Ember.js, ember-qunit, ember-twiddle
ember-moment, ember-intl, ember-table
Fabric.js
Globalize
jQuery, jQuery UI, typesense-minibar
jquery-validation, mockjax, inputmask
js-cookie
Moment.js
Paper.js
StealJS, steal-qunit, steal-tools
three.js
video.js, videojs/http-streaming, mux.js
Wikibase, data-model, data-values
ZeroClipboard
