JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://code.jquery.com/jquery-1.9.1.min.js"></script>
<div data-bind="template: { if: Comments, name: 'comments' }"></div>

<script type="tmpl" id="comments">
    <div data-bind="foreach: { data: Comments, afterAdd: $root.doSomething }">
        <div data-bind="text: name"></div>
    </div>
</script>

CSS

.wow {
    border: 2px solid green;
}

JavaScript

var vm = {
    Comments: ko.observableArray([{name:'hey'}]),
    doSomething: function (element, index, data) {
        $(element).addClass('wow');
    }
};

ko.applyBindings(vm);

vm.Comments.push({name:'foo'});
vm.Comments.push({name:'bar'});