Developers can contribute to the language at Dart's GitHub page. "The Dart SDK now has its own repository, joining the numerous Dart tools and packages already in our GitHub org [repository]. We've moved all the SDK issues over (keeping the original issue numbers), and dartbug.com now points to GitHub's issue tracker for the Dart SDK," said Seth Ladd, Google Chrome developer advocate, in a recent blog post.
Ladd advises that working on individual Dart packages -- such as args, which provide a command line parsing library, or http, which is an API for making HTTP requests -- can provide the easiest ways to contribute to Dart. "We hope our move to GitHub helps more Dartisans become active participants in the future of Dart," he said. Dart was launched in October 2011.