Sites where you can see the architecture of online roulettes and casinos?

Question

Software design

Good afternoon! There were questions about the creation of online roulette architecture. Where can I read and see the source code for examples of creating such services?
Interested in database architecture and applications. On which technology stack is it better to implement if the client wants to cover Ios / Android and web. Which platform is better to start at the beginning in order to show customers faster.
I understand that the service part will be a web api.

Answer 1

And what is the difference with the architectures of other sites? Everything is there too ... users, billing. Or do you need the source codes of the roulette wheel?