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Creates a new LoopBack4 extension.

lb4 extension [options] [<name>]


--description : Description of the extension.

--outDir : Project root directory for the extension.

--eslint : Add ESLint to LoopBack4 extension project.

--prettier : Add Prettier to LoopBack4 extension project.

--mocha : Add Mocha to LoopBack4 extension project.

--loopbackBuild : Add @loopback/build module’s script set to LoopBack4 extension project.

--vscode: Add VSCode config files to LoopBack4 application project

Standard options

-h, --help
Print the generator’s options and usage.
Do not remember prompt answers. Default is false.
Do not automatically install dependencies. Default is false.
-c, --config
JSON file name or value to configure options
Format generated code using npm run lint:fix

For example,

lb4 app --config config.json
lb4 app --config '{"name":"my-app"}'
cat config.json | lb4 app --config stdin
lb4 app --config stdin < config.json
lb4 app --config stdin << EOF
> {"name":"my-app"}
-y, --yes
Skip all confirmation prompts with default or provided value


<name> - Optional name of the extension given as an argument to the command. If provided, the tool will use that as the default when prompting for the name.

Interactive Prompts

The tool will prompt you for:

  • Name of the extension as will be shown in package.json. If the name had been supplied from the command-line, the prompt is skipped and the extension is built with the name from the command-line argument. Must follow npm naming conventions.

  • Description of the extension as will be shown in package.json.

  • Name of the directory in which to create your extension. Defaults to the name of the extension previously entered.

  • Optional modules to add to the extension. These modules are helpful tools to help format, test, and build a LoopBack4 extension. Defaults to true for all of the modules. The prompted modules are: