How angel.co custom jobs embed work

demo.html

<script data-startup="jhink" src="https://angel.co/javascripts/embed_jobs.js" id="angellist_embed" async></script>

embed.html

<style>
  .angellist_jobs {
    max-width: 800px;
    -webkit-font-smoothing: antialiased; }
  
  .angellist_jobs-job {
    margin-bottom: 16px; }
  
  .angellist_jobs-job:last-child {
    margin-bottom: 0; }
  
  .angellist_jobs-top {
    overflow: hidden; }
  
  .angellist_jobs-title {
    font-size: 16px;
    font-weight: bold;
    line-height: 24px;
    text-decoration: inherit; }
  
  .angellist_jobs-title-link,
  .angellist_jobs-title-link:hover,
  .angellist_jobs-title-link:visited,
  .angellist_jobs-title-link:active {
    color: #333333;
    font-weight: 400; }
  
  .angellist_jobs-tags {
    color: #999999;
    font-size: 14px;
    text-decoration: none; }
  
  .angellist_jobs-startup-title {
    font-size: 1.2em;
    font-weight: bold;
    line-height: 24px;
    margin-bottom: 16px; }
</style>
<div class='angellist_jobs'>
<div class='angellist_jobs-job'>
<div class='angellist_jobs-top'>
<div class='angellist_jobs-title'>
<a target="_blank" rel="" class="angellist_jobs-title-link" href="https://angel.co/jhink/jobs/102948-senior-django">Senior Django</a>
</div>
</div>
<div class='angellist_jobs-tags'>
₹50K &ndash; ₹100K &middot; 0.0% &ndash; 1.2%
&middot;
Full Time &middot; Hyderabad &middot; Backend Developer &middot; Django
</div>
</div>
</div>

embed_jobs.js

(function () {
  var element = document.getElementById('angellist_embed');
  var xmlhttp = new XMLHttpRequest();
  xmlhttp.onreadystatechange = function(){
    if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
        var div = document.createElement('div');
        div.innerHTML = xmlhttp.responseText;
        element.parentNode.insertBefore(div, element);
    }
  }
  var startup_slug = element.getAttribute('data-startup');
  xmlhttp.open("GET", "https://angel.co/job_profiles/embed?startup="+startup_slug, true);
  xmlhttp.send();

})();