Network of Internet shops

A new front-end for a large network of internet stores. The key feature is that for approximately 30 stores 1 code base is written, only the database changes, and a small file of the main setting of the store theme.
Some of them: (I repeat, code 1)
HTTPS://shop.aisleonekosher.com
HTTP://iko.prod.mycloudgrocer.com
HTTPS://next.mycloudgrocer.com
And to compare the old site https://westernkosher.com