Dart is a programming language which is used to develop web and mobile apps as well as server and desktop applications. At Google IO 2023, Google announced the stable version of Flutter as 3.10 and Dart as 3.0. With Dart 3.0, all code now has sound null safety. This leads to several benefits, such as reducing runtime errors from nulls, smaller compiled output, and improved performance.

Dart 3.0 introduces several class modifiers (abstract, mixin,) to enhance code structure and inheritance patterns. Abstract modifiers usually contain one or more abstract methods which must be implemented by any concrete (i.e., non-abstract) subclass. With Dart 3.0 mixin allows for the reuse of a class’s code in multiple class hierarchies.