Breaking news: The Flutter team has frozen all contributions to the Material and Cupertino libraries within the main Flutter framework repository. As of April 7, no new changes will be accepted in flutter/flutter for these UI component libraries. Read the Background for context.
This code freeze marks the first major milestone in a broader effort to decouple Material and Cupertino from the core Flutter framework. The next step involves re-releasing these libraries as independent packages – material_ui and cupertino_ui – on pub.dev.
“We’re thrilled to announce this important step toward a more modular Flutter architecture,” said a Flutter team spokesperson. “Freezing the code now ensures a smooth migration path for all developers when the packages go live.”
Background
The Flutter framework has historically included Material Design and Cupertino (iOS-style) widget libraries directly in its core repository. As Flutter has grown, the team decided to separate these UI libraries into their own packages for better maintainability and independent versioning.
Freezing the code one stable release cycle ahead allows the team to copy the frozen code exactly into the new packages. This minimizes the risk of breaking changes during the migration period.
What This Means for Developers
For Most Flutter App and Plugin Developers
If you write Flutter apps or plugins but do not directly contribute to Material or Cupertino, this freeze will not immediately affect your workflow. You can continue using the existing libraries inside the framework without interruption.
However, after the Flutter 3.44 stable release, the new packages will be published. At that point, developers will eventually need to migrate to the new packages. The old libraries will be deprecated in the release following 3.44 and removed later. Detailed migration instructions will be provided when the time comes.
For Contributors to Material and Cupertino
Open pull requests that touch these libraries should remain open. Reviewers will continue providing feedback as usual. Once the new packages are available, contributors will receive guidance on how to port their PRs to the flutter/packages repository. Changes will then be released as part of new material_ui or cupertino_ui versions.
Existing issues related to Material and Cupertino will stay in the flutter/flutter issue tracker. This unified approach aligns with how the team manages issues for other packages in the flutter/packages repository.
Why Freeze Now?
The primary reason for the freeze is to ensure a seamless migration experience. When the 1.0.0 versions of material_ui and cupertino_ui launch, the team wants every developer, regardless of which release channel they use, to be able to migrate without encountering breaking changes. By freezing the code in flutter/flutter one cycle ahead, the team can guarantee that both repositories remain in sync.
The migration process begins with upgrading your Flutter SDK to version 3.44 or higher. At that point, your project will contain a frozen copy of Material and Cupertino. Even if you upgrade further, that snapshot remains stable.
Editors' note: This breaking news story will be updated as more details emerge.