Version: 2020.3
Dependency and resolution

Package states and lifecycle

After developing a package to the point where it is ready for Unity users to test it and provide feedback, a package enters the preview state. Packages in this state usually appear in the Unity Editor with the label and often use preview as part of their version.

In addition to the preview packages that are discoverable in the Package Manager window, there are some preview packages that are on Unity’s package registry server but don’t appear in the Unity Registry context. These packages are not discoverable in the Package Manager window because:

- They are considered to be somewhat experimental, and therefore too risky to use in production. Some of these packages require a lot of training and expertise and are therefore recommended only in specific circumstances.
- They are support packages, meaning that you shouldn’t use them on their own because they are designed to provide shared or additional functionality to existing packages.

Undiscoverable packages can still appear in the Package Manager window if they were previously installed in your project. However, they are hidden so that users don’t discover them by accident and use them without realizing the risks.

Unity’s release management only grants a package the verified status after it passes several testing stages and validation procedures, which also include checks for appropriate documentation, changelog, and license files. Packages in this state may appear in the Unity Editor with the label and never use preview as part of their version.

If the package developer introduces changing or breaking changes to a package (either by introducing a change that breaks an API or affects its usage), that package returns to the preview state and the Package Manager does not suggest the new preview package as a possible update for the verified version.

Unity Package Manager を使ったパッケージライフサイクル
Unity Package Manager を使ったパッケージライフサイクル

These states match where the package is in the development cycle:

状態 説明
Custom パッケージ開発者がパッケージを作成中です。通常、これはパッケージが開発者のプロジェクトに埋め込まれている状態に相当します。
Preview (プレビュー) When the package is ready for testing, the Unity package developer makes sure there is some basic test coverage, and that the package passes testing with the package validation suite. The package also needs at least preliminary documentation, an updated changelog, and licensing before the Unity package developer can apply to publish the package on Unity’s official package registry.

At this point, the package is available for testing, so that any eligible Unity user can provide the developer with feedback. Most packages are available to any Unity users, although a few packages are limited to Unity IDs with specific entitlements.

Preview packages can go through many changes before they are ready to be verified for a specific version of Unity. At some point in the future, they might pass the verification requirements; however, they might also be deprecated instead. Because there is no guarantee for future support, you should not use preview packages in production. For a list of preview packages available for this version, see Preview packages.
Verified (検証済み) このパッケージは厳しいテストを受けており、この特定のバージョンの Unity と、同じバージョンで検証された他のすべてのパッケージで安全に動作することが確認されています。この状態は、Unity が内部で開発しているパッケージのみを対象としています。サードパーティのプロセスについて確認するには、そのパッケージ開発者に問い合わせてください。

パッケージが Unity の任意のバージョンで検証されると、検証されたパッケージはそのバージョンの長期サポート期間中、サポートが保証され、メジャーアップデートもマイナーアップデート (API の破壊的変更や API の変更など) も許可されません。Unity の各新バージョンで、Package Manager が検証済みとみなすには、各検証済みパッケージは再度検証プロセスを通過しなければなりません。

このバージョンの Unity で検証されたパッケージのリストを見るには、検証済みパッケージを参照してください。

注意: パッケージの中には、検証済みでもなければプレビューでもないパッケージがあります。多くの場合、これはパッケージが以前のバージョンの Unity で検証されていたにもかかわらず、現在のバージョンではまだ検証プロセスが完了していないためです。いくつかのパッケージでは、使用しても安全だと判断されたために Unity Package Manager のレジストリに公開されたにもかかわらず、検証されなかったものもあります。これらのケースでは、パッケージは本番で使用しても安全です。

The Package Manager window displays a tag that corresponds to some of these states.

  • Some advanced or support packages are no longer discoverable in the Package Manager window 2020.1 NewIn20201
Dependency and resolution