If you are developing a project, and you just want to have your client side scripts and stylesheets being updated automatically, add the following to composer.json:

{
    "require": {
     // requirements here
     },
     "scripts": {
        "post-update-cmd": [
            "bower update"
        ]
    }
}

Offcourse, you do need to make sure you actually have bower and composer installed!