In the third step of Bike Ride tutorial code for loading JavaScript assets is incorrect. The tutorial uses Bootstrap.js which depends on jQuery, so jQuery should be included first, but Assetic does it in alphabetical order. Therefore we can not open modal with bike photo.

It can be fixed this way:

{% javascripts 'assets/js/jquery.min.js'
                'assets/js/*' %}
<script src="{{ asset_url }}"></script>
{% endjavascripts %}