Package layout

This is the package layout recommended for custom packages:

<package-root>
  ├── package.json
  ├── README.md
  ├── CHANGELOG.md
  ├── LICENSE.md
  ├── Third Party Notices.md
  ├── Editor
  │   ├── <company-name>.<package-name>.Editor.asmdef
  │   └── EditorExample.cs
  ├── Runtime
  │   ├── <company-name>.<package-name>.asmdef
  │   └── RuntimeExample.cs
  ├── Tests
  │   ├── Editor
  │   │   ├── <company-name>.<package-name>.Editor.Tests.asmdef
  │   │   └── EditorExampleTest.cs
  │   └── Runtime
  │        ├── <company-name>.<package-name>.Tests.asmdef
  │        └── RuntimeExampleTest.cs
  ├── Samples~
  │        ├── SampleFolder1
  │        ├── SampleFolder2
  │        └── ...
  └── Documentation~
       └── <package-name>.md

Many official Unity packages also implement this structure.

Location	Description
`package.json`	The package manifestEach package has a manifest, which provides information about the package to the Package Manager. The manifest contains information such as the name of the package, its version, a description for users, dependencies on other packages (if any), and other details. More info See in Glossary, which defines the package dependencies and other metadata.
`README.md`	Developer package documentation. This is generally documentation to help developers who want to change the package or push a new change on the package’s main branch.
`CHANGELOG.md`	Description of package changes in reverse chronological order. It’s good practice to use a standard format, like Keep a Changelog.
`LICENSE.md`	Contains the package license text. Usually the Package Manager copies the text from the selected SPDX list website.
`Third Party Notices.md`	Contains information that’s required to meet legal requirements.
`Editor/`	Editor platform-specific Assets folder. Unlike Editor folders under Assets, this is only a convention and doesn’t affect the Asset import pipeline. Refer to Assembly definition and packages to properly configure Editor-specific assemblies in this folder.
`Runtime/`	Runtime platform-specific Assets folder. This is only a convention and doesn’t affect the Asset import pipeline. Refer to Assembly definition and packages to properly configure runtime assemblies in this folder.
`Tests/`	Folder to store any tests included in the package.
`Tests/Editor/`	Editor platform specific tests folder. Refer to Assembly definition and packages to properly configure Editor-specific test assemblies in this folder.
`Tests/Runtime/`	Runtime platform specific tests. Refer to Assembly definition and packages to properly configure runtime test assemblies in this folder.
`Samples~/`	Folder to store any samples included in the package.
`Documentation~`	Folder to store any documentation included in the package.

Unity ignores the contents of any folder name that ends with the ~ character, and doesn’t track them with .meta files. However, you need to include .meta files for the Editor, Runtime, and Tests folders and their contents in order for them to work properly. For more information on .meta files and how Unity uses them for tracking, refer to Asset workflow.

Naming your package

Adding tests to a package

Unity Manual

Package layout