How to change storefront ?

[tuanlead]

My Idea:

I had created storefront with Storefront API using Server Side Render and Single Page App (Universial Mode) and then i want to replace Online Store with Storefront created by me. When customer checkout it will be redirect to Shopify checkout page.

I have a problems when i do it:

When i sent a mail campaign, in the content email it have not a my storefront domain, it is a primary domain. I cannot set storefront domain is primary domain because i point the domain to storefront and not point to shopify. 

Expected: I use my storefront in my server, i can control performance and easy to custom logic in my storefront. In liquid theme, it's hard to implement my idea, and any app know primary domain is my storefront domain