The best way to contribute to Amper right now is to try it and share your feedback. Your input will help immensely in defining the future direction of the project.
Submit your ideas in the tracker or join the Slack channel for discussions.
As we perform various experiments around the build tool experience, the release branch becomes outdated quickly. Thus, while appreciated, external contributions to the code base will probably bring little value. Until the project development stabilizes, we encourage you to provide feedback instead.