JSFiddle - React, Tailwind, and code Playground

HTML

<input data-bind="value: text, valueUpdate: 'afterkeyup'" />

JavaScript

ViewModel = function() {
    this.text = ko.observable().extend({ throttle: 500 });
    this.text.subscribe(this.onText, this);
};

ViewModel.prototype = {
    onText: function(value) {
        console.log("ajax call");
    }
};

ko.applyBindings(new ViewModel());