Include it
<script src="src/main.js"></script>
<script>
JS.require("/mything.js", function(thing) {
thing.beAwesome();
});
</script>
You should include modules for whatever non-core functionality you need. jsframework is explicitly lightweight and doesn't impose policy -- this is a good thing!
Don't be afraid; we've got your back; as long as you are a legitimate developer! Jsframework strikes that careful balance between inclusiveness and moderation that's needed for a healthy online community.