HubSpot CRM build on which platform?

One of our client asked on which platform HubSpot CRM is built on PHP, Phyton or .Net?

Anyone have any information about this question?

According to my limited knowledge of the BTS of HubSpot and some light research, HubSpot uses 155 technology products and services including Java, HTML5 and jQuery, according to G2 Stack. Plus HubSpot uses its own custom code, HubL.