It is hard to imagine a mature Flutter project written in a single package. Sooner or later, product scale forces to split the project into multiple packages. There are multiple ways of referencing packages in pubspec.yaml. The most common of which is to use hosted packages from pub.dev. However, it is not always possible to open source the team’s work, hence there is a need for private packages. In this video, we show how private packages may be referenced and what is the most convenient way of working when you need to keep packages secret and safe.

A virtual talk by Anna and Oleksandr Leushchenko at Flutter Forward on January 25, 2023
https://youtu.be/Tc3gzg4PawA