https://medium.com/@filiph/updating-your-pub-package-to-dart-2-cd8ca343b1be

Dart 2 is imminent. If you own a package on pub.dartlang.org, you might want to make sure it’s ready.

Head over to pub and search for packages associated with your email. If you’ve been around the Dart ecosystem for a while (like me), you might have forgotten about ever writing some of these.