JSFiddle - React, Tailwind, and code Playground

HTML

<body>
<h1> Non Nobis Domine</h1>
<div id="demo"></div>

<script src="../bower_components/react/react-dom.js"></script>
<script src="../bower_components/react/react.js"></script>
<script src="../bower_components/babel/browser.js"></script>
<script src="app.js" type="text/babel"></script>
</body>

JavaScript

const user = {
    firstName: 'graity',
    lastName: 'slave'
};

function formatName() {
    return user.firstName + user.lastName;
}
ReactDOM.render(<h1>Hello {  formatName()}</h1>, document.getElementById("demo"));