Why wouldn't they, TypeScript does nothing to improve JS performance, faster start-up or iteration times, optimal tree-shaking, etc, it just makes it worse. Da

Why wouldn't they, TypeScript does nothing to improve JS performance, faster start-up or iteration times, optimal tree-shaking, etc, it just makes it worse. Dart is also focused on improving the state of web development with Web Components http://www.dartlang.org/articles/web-ui/ http://www.dartlang.org/articles/web-ui/ - fixing the DOM with a holistic and consistent API: http://www.dartlang.org/articles/improving-the-dom/ http://www.dartlang.org/articles/improving-the-dom/ - and providing a single unified abstraction for classes and IO providing much better composability than the fragmentation seen in JS.