Dart null safety migration cheat sheet

A quick reference for your second migration

If you’ve already followed the migration guides in one of these places:

• Announcing Dart null safety beta blog post
• Migrating to null safety documentation

Then you know what to do. This article is a quick summary for migrating your second package or project so that you don’t have to sift through all the details in the documentation again.

Switch to the beta channel

flutter channel beta
flutter upgrade

Check dependency status

dart pub outdated --mode=null-safety

Replace any dependencies in pubspec.yaml with the null safety version.

dart pub upgrade

Note: I had an old package that didn’t use pedantic. This made Dart complain about null safety issues too early. You can add it to pubspec.yaml like so:

dev_dependencies:
  pedantic: ^1.10.0-nullsafety.3

Migrate

dart migrate

(Skip that command if you are migrating manually.)

Get the current Dart version:

dart --version