Sometimes we want to work a new composer project locally, we can point the composer.json to the local repository:

"repositories": [
    {
        "type": "path",
        "url": "/Users/administrator/Sites/davidvandertuijn.local/vendor/your-username/your-package"
    }
]

You can then just use 'composer require your-username/your-package' as if the library is already live.