Project Configuration

Open 3D Engine (O3DE) projects define and configure the set of code and assets that make up your game or other application. Gems that you enable for your project provide some code and assets. A project directory, sometimes referred to as the “project root”, contains your projects.

To create and manage projects, you can use either the GUI-based Project Manager tool or the O3DE command line interface (CLI). The topics in this section provide details on creating O3DE projects using either of these options.

Understanding project.jsonGet a detailed look at the fields in the project manifest, an important project configuration file.
Project ManagerLearn how to create and manage projects using a GUI-based tool.
Adding and Removing GemsLearn how to add and remove Gems in your project.
Registering GemsLearn how to register external Gems from sources outside of O3DE.
O3DE CLI ReferenceLearn how to create and configure your O3DE environment and its objects, including engines, projects, and Gems, using the o3de Python script.
TroubleshootingTroubleshoot common issues that you might encounter during project configuration.
Local project.json OverridesLearn how to override the engine name and path using a project.json override file in your project’s user folder.

To build projects, use either Project Manager or CMake. For more information, refer to any of the following resources:

Understanding project.json

Each project’s root directory contains a project manifest file named project.json. This file stores important project configuration properties. O3DE creates this file for you during project creation.

To change any of the properties in this file, you can either edit the file manually using a text editor, or edit individual properties using the edit-project-properties O3DE CLI command. Additionally, you can edit the display_name property in Project Manager.

The following table describes each of the properties in project.json. The default value for many of the properties contains the project name given when you created the project. We indicate this project name as “<PROJECT_NAME>”.

The “<USER>” placeholder below refers to the user’s home directory based on the operating system being used. For example, if your user name is “Foo” and you are using a Windows machine, the <USER> directory would be C:\Users\Foo.

Operating SystemHome Directory Path
project_nameRequiredThe name of the project. The --project-name O3DE CLI parameter uses this name to identify the project.<PROJECT_NAME>
display_nameRequiredThe display name of the project in Project Manager.<PROJECT_NAME>
engineOptionalThe name of the engine and optional version specifier this project uses. Register engines in your O3DE manifest, located at <USER>/.o3de/o3de_manifest.json.“o3de”
engine_api_dependenciesOptionalA list of engine API dependencies. If empty, the project is assumed compatible with all versions of any engine APIs.""
external_subdirectoriesOptionalThe path to one or more directories to include in the project build. You can use any directory with a CMakeLists.txt file. When you register Gems to the project using the register --external-subdirectory-project-path O3DE CLI command, O3DE adds their paths here.[ ]
canonical_tagsRequiredA standard field in O3DE manifests used to identify an O3DE object’s type. Examples: “Gem”, “Project”. Projects should use the “Project” tag.[ “Project” ]
compatible_enginesOptionalA list of engine names and optional version specifiers that this project is known to be compatible with: i.e. o3de>=2.0.0, o3de-sdk==1.2.0, o3de-custom etc. If empty, the project is assumed compatible with all engines if they meet all the requirements in the engine_api_dependencies and gem_names fields.[ ]
gem_namesOptionalA list of gem names and optional version specifiers that this project uses, including the Gem included in the project: i.e. Atom, PopcornFX==1.2.0 etc.[ “<PROJECT_NAME>” ]
icon_pathOptionalThe path and filename of the project icon. Project Manager uses this icon. The file must be located in the project root directory. The current recommended size is 210px wide and 280px high.“preview.png”
licenseRequiredThe license that the project uses, and any copyright information that you want to include. Consider providing the URL for the license. This field is intended for Project Manager to use.“What license <PROJECT_NAME> uses goes here: i.e."
originOptionalA URL for the project, such as the repository URL or project website. This field is intended for Project Manager to use.“The primary repo for <PROJECT_NAME> goes here: i.e.
project_idOptionalA UUID that is generated when the project is created.“< UUID >”
restricted_nameOptionalThe name of a restricted folder to associate with the project.<PROJECT_NAME>
summaryOptionalA short description of the project. This field is intended for Project Manager to use.“A short description of <PROJECT_NAME>.”
user_tagsOptionalAny keyword tags that you want to associate with the project. Examples: “Physics”, “Assets”, “AWS”. For examples of the standard set of tags that Gems use, refer to the Project Manager Gem Catalog. Project Manager uses these tags for documentation, search, and filtering.[ “<PROJECT_NAME>” ]
versionOptionalThe MAJOR.MINOR.PATCH semantic version that is updated as changes are made to the project.“1.0.0”

Local project.json Overrides

When you have multiple engines installed locally it can be useful to make your project use an engine with a specific name or path without changing the project.json file shared with your team. O3DE will use settings in the user/project.json overrides file in your project folder to override project.json file settings in the project root.

To change any of the properties in the user/project.json overrides file, you can either edit the file manually using a text editor, or edit individual properties using the edit-project-properties O3DE CLI command with the --user option. The Project Manager will set the engine_path in this file when you add a project.

engineEngine name override with optional specifier“o3de==1.2.3”
engine_pathThe absolute local path to the engine to use“C:/o3de-custom”


A developer is using git worktrees to work on multiple branches of the o3de GitHub repository at the same time. The engine_name is the same for every engine instance, so the developer uses the user/project.json file to set the engine_path to the specific engine they want to use.


An engine developer works on a team that stores the engine SDK and project in source control but keeps the engine source code in a separate repository. The developer has both repositories on their machine locally:

            /o3de-sdk <-- engine SDK
            /project  <-- project
            /o3de     <-- engine source code

Because the developer is building the engine from source and doesn’t want to use the SDK, they set the engine_path setting to /home/user/repo2/o3de in the project’s /home/user/repo1/project/user/project.json overrides file.