JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://cdn.ractivejs.org/edge/ractive.js"></script>
<main></main>

<script id='template' type='text/ractive'>
    <label><input decorator='myDeco' value='{{a}}'/></label>
    
    <p>{{a}}</p>
</script>

CSS

body {
    font-family: 'Helvetica Neue', arial, sans-serif;
    font-weight: 200;
    color: #353535;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 200;
}

label {
    display: block;
}

JavaScript

var myDecorator = function(node){
    console.log('deco', node)
    console.log('value prev',node.value)
    console.log('upper',node.value.toUpperCase())
    
    node.value = node.value.toUpperCase();
    
    console.log('valueafter',node.value)
    
    
    return {
     	teardown :  function(){ 
        }
    }
}

var ractive = new Ractive({
    el: 'main',
    template: '#template',
    data: { a: 'AbC' },
    decorators: {myDeco:myDecorator}
});