To create a large portal or online store, is it better to create your own engine for it or do it on pure HTML code?

Question

CMS

For example, large sites - vc.ru, the same habrahabr, geektimes, toster; shops - Lamoda, Ozone, etc.

Answer 1

in pure HTML

Answer 2

To create a large portal, you need to find and pay money to interesting authors. Store to build impeccable logistics. The engine is a secondary matter.