From the [component/component](https://github.com/component/component) [spec](https://github.com/component/component/wiki/Spec):
> It is recommended that you use "index.js" for the main component file, however if you use another filename, you **MUST** define a "main" field for that. A component **MUST** have only one "main" file specified, and it **MUST** still be listed in the "scripts" array.